Bauer, Anne, Baltay, Charles, Coppi, Paolo, Donalek, Ciro, Drake, Andrew, Djorgovski, S. G., ...
We identify 3113 highly variable objects in 7200 deg^2 of the Palomar-QUEST (PQ) Survey, which each varied by more than 0.4 mag simultaneously in two broadband optical filters on timescales from...
Bauer, Anne, Baltay, Charles, Coppi, Paolo, Donalek, Ciro, Drake, Andrew, Djorgovski, S. G., ...
We identify 3,113 highly variable objects in 7,200 square degrees of the Palomar-QUEST Survey, which each varied by more than 0.4 magnitudes simultaneously in two broadband optical filters on...
Binary Quasars at High Redshift I: 24 New Quasar Pairs at z ~ 3-4 (2009)
Hennawi, Joseph F., Myers, Adam D., Shen, Yue, Strauss, Michael A., Djorgovski, S. G., Fan, Xiaohui, ...
The clustering of quasars on small scales yields fundamental constraints on models of quasar evolution and the buildup of supermassive black holes. This paper describes the first systematic survey to...
Binary Quasars at High Redshift II: Sub-Mpc Clustering at z ~ 3-4 (2009)
Shen, Yue, Hennawi, Joseph F., Shankar, Francesco, Myers, Adam D., Strauss, Michael A., Djorgovski, S. G., ...
We present measurements of the small-scale (0.1
Discovery of the Extremely Energetic Supernova 2008fz (2009)
Drake, A. J., Djorgovski, S. G., Prieto, J. L., Mahabal, A., Balam, D., Williams, R., ...
We report on the discovery and initial observations of the energetic type IIn supernova (SN), 2008fz. The optical energy emitted by SN 2008fz (based on the light curve over a 88 day period), is...
Djorgovski, S. G., Hut, P., McMillan, S., Vesperini, E., Knop, R., Farr, W., ...
We describe the Meta-Institute for Computational Astrophysics (MICA), the first professional scientific organization based exclusively in virtual worlds (VWs). The goals of MICA are to explore the...
The velocity dispersion and mass-to-light ratio of the remote halo globular cluster NGC 2419 (2009)
Baumgardt, H., Côté, P., Hilker, M., Rejkuba, M., Mieske, S., Djorgovski, S. G., ...
Precise radial velocity measurements from high-resolution echelle spectrometer on the Keck I telescope are presented for 40 stars in the outer halo globular cluster NGC 2419. These data are used to...
The Palomar Transient Factory: System Overview, Performance and First Results (2009)
Law, N. M., Kulkarni, S. R., Dekany, R. G., Ofek, E. O., Quimby, R. M., Nugent, P. E., ...
The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey aimed at a systematic exploration of the optical transient sky. The transient survey is performed using a new 8.1 square...
Skyalert: Real-time Astronomy for You and Your Robots (2009)
Williams, R. D., Djorgovski, S. G., Drake, A. J., Graham, M. J., Mahabal, A.
Skyalert.org is a web application to collect and disseminate observations about time-critical astronomical transients, and to add annotations and intelligent machine-learning to those observations....
Jordi, K., Grebel, E. K., Hilker, M., Baumgardt, H., Frank, M., Kroupa, P., ...
We use the distant outer halo globular cluster Palomar 14 as a test case for classical versus modified Newtonian dynamics (MOND). Previous theoretical calculations have shown that the line-of-sight...
First Results from the Catalina Real-Time Transient Survey (2009)
Drake, A. J., Djorgovski, S. G., Mahabal, A., Beshore, E., Larson, S., Graham, M. J., ...
We report on the results from the first six months of the Catalina Real-Time Transient Survey (CRTS). In order to search for optical transients (OTs) with timescales of minutes to years, the CRTS...
The velocity dispersion and mass-to-light ratio of the remote halo globular cluster NGC 2419 (2009)
Baumgardt, H., Cote, P., Hilker, M., Rejkuba, M., Mieske, S., Djorgovski, S. G., ...
Precise radial velocity measurements from HIRES on the Keck I telescope are presented for 40 stars in the outer halo globular cluster NGC 2419. These data are used to probe the cluster's stellar mass...
The Environments of High-Redshift Quasi-Stellar Objects (2009)
Kim, Soyoung, Stiavelli, Massimo, Trenti, M., Pavlovsky, C. M., Djorgovski, S. G., Scarlata, C., ...
We present a sample of i_(775)-dropout candidates identified in five Hubble Advanced Camera for Surveys (ACS) fields centered on Sloan Digital Sky Survey quasi-stellar objects (QSOs) at redshift z ~...
Thirty Meter Telescope Site Testing I: Overview (2009)
Schoeck, M., Els, S., Riddle, R., Skidmore, W., Travouillon, T., Blum, R., ...
As part of the conceptual and preliminary design processes of the Thirty Meter Telescope (TMT), the TMT site testing team has spent the last five years measuring the atmospheric properties of five...
Thirty Meter Telescope Site Testing I: Overview (2009)
Schöck, M., Els, S., Riddle, R., Skidmore, W., Travouillon, T., Blum, R., ...
As part of the conceptual and preliminary design processes of the Thirty Meter Telescope (TMT), the TMT site-testing team has spent the last five years measuring the atmospheric properties of five...
Jordi, K., Grebel, E. K., Hilker, M., Baumgardt, H., Frank, M., Kroupa, P., ...
We use the distant outer halo globular cluster Palomar 14 as a test case for classical vs. modified Newtonian dynamics (MOND). Previous theoretical calculations have shown that the line-of-sight...
Cosmological Studies with Radio Galaxies and Supernovae (2009)
Daly, Ruth A., Mory, Matthew P., O'Dea, C. P., Kharb, P., Baumont, S., Guerra, E. J., ...
Physical sizes of extended radio galaxies can be employed as a cosmological "standard ruler," using a previously developed method. Eleven new radio galaxies are added to our previous sample of 19...
The Northern Sky Optical Cluster Survey. III. A Cluster Catalog Covering PI Steradians (2009)
Gal, R. R., Lopes, P. A. A., De Carvalho, R. R., Kohl-Moreira, J. L., Capelato, H. V., Djorgovski, S. G.
We present the complete galaxy cluster catalog from the Northern Sky Optical Cluster Survey, a new, objectively defined catalog of candidate galaxy clusters at z ≾ 0.25 drawn from the Digitized...
The Northern Sky Optical Cluster Survey III: A Cluster Catalog Covering Pi Steradians (2008)
Gal, R. R., Lopes, P. A. A., De Carvalho, R. R., Kohl-Moreira, J. L., Capelato, H. V., Djorgovski, S. G.
We present the complete galaxy cluster catalog from the Northern Sky Optical Cluster Survey, a new, objectively defined catalog of candidate galaxy clusters at z
Towards real-time classification of astronomical transients (2008)
Mahabal, A., Djorgovski, S. G., Williams, R., Drake, A., Donalek, C., Graham, M., ...
Exploration of time domain is now a vibrant area of research in astronomy, driven by the advent of digital synoptic sky surveys. While panoramic surveys can detect variable or transient events,...
New approaches to object classification in synoptic sky surveys (2008)
Donalek, C., Mahabal, A., Djorgovski, S. G., Marney, S., Drake, A., Glikman, E., ...
Digital synoptic sky surveys pose several new object classification challenges. In surveys where real-time detection and classification of transient events is a science driver, there is a need for an...
New Approaches to Object Classification in Synoptic Sky Surveys (2008)
Donalek, C., Mahabal, A., Djorgovski, S. G., Marney, S., Drake, A., Glikman, E., ...
Digital synoptic sky surveys pose several new object classification challenges. In surveys where real-time detection and classification of transient events is a science driver, there is a need for an...
Towards Real-time Classification of Astronomical Transients (2008)
Mahabal, A., Djorgovski, S. G., Williams, R., Drake, A., Donalek, C., Graham, M., ...
Exploration of time domain is now a vibrant area of research in astronomy, driven by the advent of digital synoptic sky surveys. While panoramic surveys can detect variable or transient events,...
First Results from the Catalina Real-time Transient Survey (2008)
Drake, A. J., Djorgovski, S. G., Mahabal, A., Beshore, E., Larson, S., Graham, M. J., ...
We report on the results from the first six months of the Catalina Real-time Transient Survey (CRTS). In order to search for optical transients with timescales of minutes to years, the CRTS analyses...
An exploratory search for z ≳ 6 quasars in the UKIDSS early data release (2008)
Glikman, Eilat, Eigenbrod, Alexander, Djorgovski, S. G., Meylan, Georges, Thompson, David, Mahabal, Ashish, ...
We conducted an exploratory search for quasars at z ~ 6-8, using the Early Data Release (EDR) from the United Kingdom Infrared Deep Sky Survey (UKIDSS) cross-matched to panoramic optical imagery....
An Exploratory Search for z~6 Quasars in the UKIDSS Early Data Release (2008)
Glikman, Eilat, Eigenbrod, Alexander, Djorgovski, S. G., Meylan, Georges, Thompson, David, Mahabal, Ashish, ...
We conducted an exploratory search for quasars at z~ 6 - 8, using the Early Data Release from United Kingdom Infrared Deep Sky survey (UKIDSS) cross-matched to panoramic optical imagery. High...
The Environments of High Redshift QSOs (2008)
Kim, Soyoung, Stiavelli, Massimo, Trenti, M., Pavlovsky, C. M., Djorgovski, S. G., Scarlata, C., ...
We present a sample of $i_{775}$-dropout candidates identified in five Hubble Advanced Camera for Surveys fields centered on Sloan Digital Sky Survey QSOs at redshift $z\sim 6$. Our fields are as...
Daly, Ruth A., Djorgovski, S. G., Freeman, Kenneth A., Mory, Matthew P., O'Dea, C. P., Kharb, P., ...
We extend and apply a model-independent analysis method developed earlier by Daly & Djorgovski to new supernova, radio galaxy, and galaxy cluster samples to study the acceleration history of the...
The Origins and the Early Evolution of Quasars and Supermassive Black Holes (2008)
Djorgovski, S. G., Volonteri, M., Springel, V., Bromm, V., Meylan, G.
The relationship between galaxies and supermassive black holes (SMBH) found in their cores plays a key role in the formation and evolution of both of these major constituents of the universe, as well...
Automated Probabilistic Classification of Transients and Variables (2008)
Mahabal, A. A., Djorgovski, S. G., Turmon, M., Jewell, J., Williams, R. R., Drake, A. J., ...
There is an increasing number of large, digital, synoptic sky surveys, in which repeated observations are obtained over large areas of the sky in multiple epochs. Likewise, there is a growth in the...
The Palomar-Quest Digital Synoptic Sky Survey (2008)
Djorgovski, S. G., Baltay, C., Mahabal, A. A., Drake, A. J., Williams, R., Rabinowitz, D., ...
We describe briefly the Palomar-Quest (PQ) digital synoptic sky survey, including its parameters, data processing, status, and plans. Exploration of the time domain is now the central scientific and...
The origins and the early evolution of quasars and supermassive black holes (2008)
Djorgovski, S. G., Volonteri, Marta, Springel, Volker, Bromm, Volker, Meylan, Georges
Analysis of Digital POSS-II Catalogs Using Hierarchical Unsupervised Learning Algorithms (2007)
Jungsoon Yoo, Er Gray, Joseph Roden, Usama M. Fayyad, S. G. Djorgovski
. We apply techniques from the field of machine learning/ artificial intelligence to the problem of inducing meaningful structure from astronomical data. Cobweb/95 is a concept formation system that...
Image Deconvolution of the Radio Ring PKS 1830--211 (2007)
F. Courbin, C. Lidman, B. L. Frye, P. Magain, T. J. Broadhurst, ...
New high quality Keck and ESO images of PKS 1830--211 are presented. Applying a powerful new deconvolution algorithm to these optical and infrared data, both images of the flat spectrum core of the...
The unusual afterglow of GRB 980326: evidence for the gamma-ray burst/supernova connection (2007)
Bloom Kulkarni, J. S. Bloom, S. R. Kulkarni, S. G. Djorgovski, A. C. Eichelberger, J. P. Blakeslee, ...
this paper in your own paper. However, we do place restrictions on any dissemination in the popular media. The article is under embargo until it is published. For further enquiries, please contact...
+656: A Quadruple Lens System Found in the CLASS Gravitational Lens Survey (2007)
S. T. Myers, Myers Fassnacht, S. G. Djorgovski, R. D. Bl, K. Matthews, G. Neugebauer, ...
The first phase of a large gravitational lens survey using the Very Large Array at a wavelength of 3.6 cm has been completed, yielding images for 3258 radio sources. The Cosmic Lens All-Sky Survey,...
The Possible Redshift Clumping of Damped Lyman-alpha Absorbers (2007)
Introduction The observed redshift distribution of known damped Lyman-ff systems (DLAs) seems to show clumping at several specific redshifts. Our tests show this clumping to be marginally...
Observatory Technologies (2007)
A. S. Szalay, R. J. Brunner, R. J. Brunner, T. Prince, J. Good, C. Lonsdale, ...
Abstract. Astronomy is entering a new era as multiple, large area, digital sky surveys are in production. The resulting datasets are truly remarkable in their own right; however, a revolutionary step...
ON THE THRESHOLD OF THE REIONIZATION EPOCH 1 (2007)
S. G. Djorgovski, S. Castro, D. Stern, A. A. Mahabal
Discovery of the cosmic reionization epoch would represent a significant milestone in cosmology. We present Keck spectroscopy of the quasar SDSS 1044#0125, at. The spectrum shows a dramatic increase...
The Fundamental Plane of Elliptical Galaxies: An Overview, and Some New Results (2007)
Abstract. A brief review is given of the Fundamental Plane (FP) correlations of elliptical galaxies, and their implications for the formation and dynamical structure of ellipticals. New surface...
Observational Constraints on the Origins of the Fundamental Plane (2007)
Stromlo Symposium, M. Arnaboldi, P. Saha, M. A. Pahre, S. G. Djorgovski
Abstract: We review the concept of the Fundamental Plane (FP), and present new results on the near--infrared FP. We show that the K--band FP differs both from the optical form and the virial...
, and R. R. de Carvalho (2007)
Michael A. Pahre, S. G. Djorgovski
We use the intercept of the elliptical galaxy radius--surface brightness (SB) relation at a fixed metric radius as the standard condition for the Tolman SB test of the universal expansion. We use...
The Near--Infrared Fundamental Plane of Elliptical Galaxies and Its Evolution (2007)
Abstract. We present the first Fundamental Plane (FP) that has been constructed in the K--band using near--infrared imaging source data. The slope of this IR FP differs systematically both from the...
Michael A. Pahre, S. G. Djorgovski
Near--infrared imaging data on 251 early--type galaxies in clusters and groups are used to construct the near--infrared Fundamental Plane (FP) r eff / oe
S. G. Djorgovski, M. Pahre, R. R. Gal, A. Gray, J. Roden
The subjective nature of the Abell catalog has been widely recognized as its major limitation. We report on the preliminary results of an effort to create an unbiased catalog of clusters of galaxies...
S. G. Djorgovski, R. Scaramella, G. Longo
The Second Palomar Sky Survey (POSS-II) is now nearing completion. It will cover the entire northern sky with 894 fields (6:5 ffi square) at 5 ffi spacings, and no gaps in the coverage. Plates are...
Palomar Observatory, Caltech (2007)
Abstract. The Fundamental Plane (FP) scaling relations and their evolution are a powerful tool for studying the global properties of early-type galaxies and their evolutionary history. The form of...
Michael A. Pahre, S. G. Djorgovski, Jill Bechtold, Richard Elston
We report the detection, both in line and continuum emission, of a galaxy responsible for a damped Lyff absorption (DLA) system at z = 3:15 projected 2:3
Systematic Variations in Age and Metallicity Along the Early-Type Galaxy Sequence (2007)
Michael A. Pahre, S. G. Djorgovski
Abstract. The form of the early-type galaxy scaling relation (the Fundamental Plane or FP) is a direct indicator of the underlying physical origins for the galaxy sequence. Observed properties of the...
Image Deconvolution of the Radio Ring PKS 1830--211 1 (2007)
F. Courbin, C. Lidman, B. L. Frye, P. Magain, T. J. Broadhurst, M. A. Pahre, ...
New high quality Keck and ESO images of PKS 1830--211 are presented. Applying a powerful new deconvolution algorithm to this optical and infrared data, both images of the flat spectrum core of the...
Michael A. Pahre, S. G. Djorgovski
The physical origins of the Fundamental Plane (FP) scaling relations are investigated using large samples of early--type galaxies observed at optical and near--infrared wavelengths. The slope a in...
Michael A. Pahre, Judith G. Cohen, Gerry Neugebauer, David W. Hogg, Roger D, S. G. Djorgovski, ...
, Thomas H. Jarrett 7, and T. N. Gautier 8 This paper describes the photometric imaging data used to construct a near--infrared selected sample of 195 objects to K = 20 mag, as part of a redshift...
, and R. R. de Carvalho (2007)
Michael A. Pahre, S. G. Djorgovski
1;4 We present results from a near-infrared K-band imaging survey of 59 elliptical galaxies in five nearby clusters. We measure photometric parameters for each galaxy using surface photometry and...
The Acceleration History of the Universe and the Properties of the Dark Energy (2007)
Daly, Ruth A., Djorgovski, S. G.
The model-independent method of using type Ia supernovae proposed and developed by Daly and Djorgovski (2003, 2004) has been applied to the Riess et al. (2007) supernovae sample. Assuming only a...
Daly, Ruth A., Djorgovski, S. G., Freeman, Kenneth A., Mory, Matthew P., O'Dea, C. P., Kharb, P., ...
We extend and apply a model-independent analysis method developed earlier by Daly & Djorgovski to new samples of supernova standard candles, radio galaxy and cluster standard rulers, and use it to...
Cosmological Studies with Radio Galaxies and Supernovae (2007)
Daly, Ruth A., Mory, Matthew P., O'Dea, C. P., Kharb, P., Baum, S., Guerra, E. J., ...
Physical sizes of extended radio galaxies can be employed as a cosmological "standard ruler", using a previously developed method. Eleven new radio galaxies are added to our previous sample of...
The Acceleration History of the Universe and the Properties of the Dark Energy (2007)
Daly, Ruth A., Djorgovski, S. G.
The model-independent method of using type Ia supernovae proposed and developed by Daly & Djorgovski (2003, 2004) has been applied to the Riess et al. (2007) supernovae sample. Assuming only a...
Busso, G., Cassisi, S., Piotto, G., Castellani, M., Romaniello, M., Catelan, M., ...
Context. In this paper we present multiband optical and UV Hubble Space Telescope photometry of the two Galactic globular clusters NGC 6388 and NGC 6441. Aims. We investigate the properties of their...
Busso, G., Cassisi, S., Piotto, G., Castellani, M., Romaniello, M., Catelan, M., ...
In this paper we present multiband optical and UV Hubble Space Telescope photometry of the two Galactic globular clusters NGC 6388 and NGC 6441. We have obtained the first UV color-magnitude diagrams...
Berger, E., Chary, R., Cowie, L. L., Price, P. A., Schmidt, B. P., Fox, D. B., ...
We present deep Hubble Space Telescope (HST ) and Spitzer Space Telescope observations of GRB 050904 at z = 6:295. We detect the afterglow in the H band more than 3 weeks after the burst and confirm...
Discovery of two spectroscopically peculiar, low-luminosity quasars at z ~ 4 (2007)
Glikman, Eilat, Djorgovski, S. G., Stern, Daniel, Bogosavljević, Milan, Mahabal, Ashish
We report the discovery of two low-luminosity quasars at z ~ 4, both of which show prominent N iv] λ1486 emission. This line is extremely rare in quasar spectra at any redshift; detecting it in two...
Discovery of Two Spectroscopically Peculiar, Low-Luminosity Quasars at z~4 (2007)
Glikman, Eilat, Djorgovski, S. G., Stern, Daniel, Bogosavljevic, Milan, Mahabal, Ashish
We report the discovery of two low-luminosity quasars at z~4, both of which show prominent N IV] 1486A emission. This line is extremely rare in quasar spectra at any redshift; detecting it in two out...
Evidence for overdensity around zem > 4 quasars from the proximity effect (2007)
Guimarães, R., Petitjean, P., Rollinde, E., De Carvalho, R. R., Djorgovski, S. G., Srianand, R., ...
We study the density field around zem > 4 quasars using high-quality medium spectral resolution Echelle Spectrograph and Imager–Keck spectra ( R∼ 4300 , signal-to-noise ratio (S/N) > 25) of 45...
The ERO Host Galaxy of GRB 020127: Implications for the Metallicity of GRB Progenitors (2007)
Berger, E., Fox, D. B., Kulkarni, S. R., Frail, D. A., Djorgovski, S. G.
We present optical and near-IR observations of the host galaxy of GRB 020127, for which we measure R - K_s = 6.2 mag. This is only the second GRB host to date classified as an ERO. The spectral...
Discovery of a Probable Physical Triple Quasar (2007)
Djorgovski, S. G., Courbin, F., Meylan, G., Sluse, D., Thompson, D. J., Mahabal, A., ...
We report the discovery of the first known probable case of a physical triple quasar (not a gravitational lens). A previously known double system, QQ 1429-008 at z = 2.076, is shown to contain a...
Integrated-light Two Micron All Sky Survey infrared photometry of Galactic globular clusters (2007)
Cohen, Judith G., Hsieh, Scott, Metchev, Stanimir, Djorgovski, S. G., Malkan, M.
We have mosaicked Two Micron All Sky Survey (2MASS) images to derive surface brightness profiles in J, H, and K_s for 104 Galactic globular clusters. We fit these with King profiles and show that the...
Object detection in multi-epoch data (2006)
Babu, G. Jogesh, Mahabal, Ashish, Djorgovski, S. G., Williams, R.
In astronomy multiple images are frequently obtained at the same position of the sky for follow-up co-addition as it helps one go deeper and look for fainter objects. With large scale panchromatic...
Dark Energy From Vacuum Fluctuations (2006)
Djorgovski, S. G., Gurzadyan, V. G.
We describe briefly a novel interpretation of the physical nature of dark energy (DE), based on the vacuum fluctuations model by Gurzadyan & Xue, and describe an internally consistent solution for...
Daly, Ruth A., Djorgovski, S. G.
Understanding the acceleration of the universe and its cause is one of the key problems in physics and cosmology today, and is best studied using a variety of mutually complementary approaches. Daly...
Integrated Light 2MASS IR Photometry of Galactic Globular Clusters (2006)
Cohen, Judith G., Hsieh, Scott, Metchev, Stanimir, Djorgovski, S. G., Malkan, M.
We have mosaiced 2MASS images to derive surface brightness profiles in JHK for 104 Galactic globular clusters. We fit these with King profiles, and show that the core radii are identical to within...
The ERO Host Galaxy of GRB 020127: Implications for the Metallicity of GRB Progenitors (2006)
Berger, E., Fox, D. B., Kulkarni, S. R., Frail, D. A., Djorgovski, S. G.
We present optical and near-IR observations of the host galaxy of GRB 020127, for which we measure R-K=6.2 mag. This is only the second GRB host to date, which is classified as an ERO. The spectral...
Some Pattern Recognition Challenges in Data-Intensive Astronomy (2006)
Djorgovski, S. G., Donalek, C., Mahabal, A., Williams, R., Drake, A., Graham, M., ...
We review some of the recent developments and challenges posed by the data analysis in modern digital sky surveys, which are representative of the information-rich astronomy in the context of Virtual...
Lopes, P. A. A., De Carvalho, R. R., Capelato, H. V., Gal, R. R., Djorgovski, S. G., Brunner, R. J., ...
We present a comparison of optical and X-ray properties of galaxy clusters in the northern sky. We determine the recovery rate of X-ray detected clusters in the optical as a function of richness,...
A Search for z 6 QSOs in the Palomar-Quest Sky Survey (2006)
L. Carrasco, C. Baltay, Y. D. Mayya, G. A. Escobedo, E. Castillo, D. Rabinowitz, ...
A Search for z 6 QSOs in the Palomar-Quest Sky Survey
Berger, E., Chary, R., Cowie, L. L., Price, P. A., Schmidt, B. P., Fox, D. B., ...
We present deep Hubble Space Telescope and Spitzer Space Telescope observations of the host galaxy of GRB 050904 at z=6.295. The host is detected in the H-band and marginally at 3.6 micron. From...
Constraints on the Physical Parameters of the Dark Energy Using a Model-Independent Approach (2005)
Daly, Ruth A., Djorgovski, S. G.
Understanding the physical nature of the dark energy which appears to drive the accelerated expansion of the unvierse is one of the key problems in physics and cosmology today. This important problem...
Recio-Blanco, A., Aparicio, A., Piotto, G., De Angeli, F., Djorgovski, S. G.
The interpretation of globular cluster horizontal branch (HB) morphology is a classical problem that can significantly blur our understanding of stellar populations. In this paper, we present a new...
Mahabal, A., Stern, D., Bogosavljevic, M., Djorgovski, S. G., Thompson, D.
We present observations of an optically-faint quasar, RD J114816.2+525339, discovered from deep multi-color observations of the field around the z = 6.42 quasar SDSS J1148+5251. The two quasars have...
Quasars as Probes of Late Reionization and Early Structure Formation (2005)
Djorgovski, S. G., Bogosavljevic, M., Mahabal, A.
Observations of QSOs at z ~ 5.7 - 6.4 show the appearance of Gunn-Peterson troughs around z ~ 6, and a change in the slope of the IGM optical depth tau(z) near z ~ 5.5. These results are interpreted...
CO and Dust in PSS2322+1944 at a redshift of 4.12 (2005)
Cox, P., Omont, A., Djorgovski, S. G., Bertoldi, F., Pety, J., Carilli, C. L., ...
Using the IRAM interferometer we have detected J=4-3 and 5-4 CO line emission toward the radio quiet quasar PSS2322+1944. At a redshift of z_CO=4.1199 this is the fourth and strongest detection of CO...
A Molecular Einstein Ring: Imaging a Starburst Disk Surrounding a Quasi-Stellar Object (2005)
Carilli, C. L., Lewis, G. F., Djorgovski, S. G., Mahabal, A., Cox, P., Bertoldi, F., ...
Images of the CO 2-1 line emission, and the radio continuum emission, from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter...
Staguhn, J. G., Stern, D., Benford, D. J., Bertoldi, F., Djorgovski, S. G., Thompson, D.
With a redshift of z=5.5 and an optical blue magnitude M_B ~ -24.2 mag (~4.5 10^12 L_sun), RDJ030117+002025 is the most distant optically faint (M_B > -26 mag) quasar known. MAMBO continuum...
Color Gradients in Early-type Galaxies: Dependence on Environment and Redshift (2005)
La Barbera, F., De Carvalho, R. R., Gal, R., Busarello, G., Merluzzi, P., Capaccioli, M., ...
Color gradients in early-type galaxies contain valuable clues about their formation and evolutionary histories and mechanisms. We examine color gradients in 1,700 early-type galaxies in 159 galaxy...
Virtual Astronomy, Information Technology, and the New Scientific Methodology (2005)
All sciences, including astronomy, are now entering the era of information abundance. The exponentially increasing volume and complexity of modern data sets promises to transform the scientific...
A Catalog of Distant Compact Groups Using DPOSS (2005)
De Carvalho, R. R., Goncalves, T. S., Iovino, A., Kohl-Moreira, J. L., Gal, R. R., Djorgovski, S. G.
In this paper we present an objectively defined catalog of 459 small, high density groups of galaxies out to z~0.2 in a region of 6260 square degrees in the northern sky derived from the Digitized...
Virtual Observatory: From Concept to Implementation (2005)
Djorgovski, S. G., Williams, R.
We review the origins of the Virtual Observatory (VO) concept, and the current status of the efforts in this field. VO is the response of the astronomical community to the challenges posed by the...
Hasegan, Monica, Jordan, Andres, Cote, Patrick, Djorgovski, S. G., McLaughlin, Dean E., Blakeslee, John P., ...
We investigate the connection between globular clusters and ultra-compact dwarf galaxies (UCDs) by examining the properties of several compact objects associated with M87, all of which were...
Evidence for Primordial Clustering Around the QSO SDSS J1030+0524 at z=6.28 (2005)
Stiavelli, M., Djorgovski, S. G., Pavlovsky, C., Scarlata, C., Stern, D., Mahabal, A., ...
We present tentative evidence for primordial clustering, manifested as an excess of color-selected objects in the field of the QSO SDSS J1030+0524 at redshift z=6.28. We have selected objects red in...
HST/WFPC2 Color-Magnitude Diagrams for Globular Clusters in M31 (2005)
Rich, R. M., Corsi, C. E., Cacciari, C., Federici, L., Pecci, F. Fusi, Djorgovski, S. G.
We report new HST/WFPC2 photometry for 10 globular clusters (GC) in M31 observed in F5555W(V) and F814W(I). Additionally we have reanalyzed HST archival data of comparable quality for 2 more GCs....
Morphology of low-redshift compact galaxy clusters I. Shapes and radial profiles (2005)
Strazzullo, V., Paolillo, M., Longo, G., Puddu, E., Djorgovski, S. G., De Carvalho, R. R., ...
The morphology of clusters of galaxies may be described with a set of parameters which contain information about the formation and evolutionary history of these systems. In this paper we present a...
Virtual Observatory: From Concept to Implementation (2005)
Djorgovski, S. G., Williams, R.
We review the origins of the Virtual Observatory (VO) concept, and the current status of the efforts in this field. VO is the response of the astronomical community to the challenges posed by the...
Virtual Astronomy, Information Technology, and the New Scientific Methodology (2005)
All sciences, including astronomy, are now entering the era of information abundance. The exponentially increasing volume and complexity of modern data sets promises to transform the scientific...
Time Domain Explorations With Digital Sky Surveys (2005)
Mahabal, Ashish A., Djorgovski, S. G., Graham, M. J., Kollipara, Priya, Granett, Benjamin, Krause, Elisabeth, ...
One of the new frontiers of astronomical research is the exploration of time variability on the sky at different wavelengths and flux levels. We have carried out a pilot project using DPOSS data to...
A Search for z 6 QSOs in the Palomar-Quest Sky Survey (2005)
Baltay , C., Bauer , A., Carrasco , L., Castillo , E., Djorgovski , S. G., Escobedo , G. A., ...
Time Domain Explorations With Digital Sky Surveys (2004)
Mahabal, A. A., Djorgovski, S. G., Graham, M. J., Kollipara, P., Granett, B., Krause, E., ...
One of the new frontiers of astronomical research is the exploration of time variability on the sky at different wavelengths and flux levels. We have carried out a pilot project using DPOSS data to...
Palomar-QUEST: A case study in designing sky surveys in the VO era (2004)
Graham, Matthew J., Williams, Roy, Djorgovski, S. G., Mahabal, Ashish, Baltay, Charles, Rabinowitz, Dave, ...
The advent of wide-area multicolour synoptic sky surveys is leading to data sets unprecedented in size, complexity and data through- put. VO technology offers a way to exploit these to the full but...
Exploring the Time Domain with the Palomar-QUEST Sky Survey (2004)
Mahabal, A., Djorgovski, S.G., Graham, M., Williams, R., Granett, B., Bogosavljevic, M., ...
Discoveries in astronomy are often made through a systematic exploration of previously poorly covered regions of the observable parameter space [1,2]. In particular, exploration of the time...
The cosmic reionization era, which includes formation of the first stars, galaxies, and AGN, is now one of the most active frontiers of cosmological research. We review briefly our current...
Exploring the Time Domain with the Palomar-QUEST Sky Survey (2004)
Mahabal, A., Djorgovski, S. G., Graham, M. J., Williams, R., Granett, B., Bogosavljevic, M., ...
Exploration of the time variability on the sky over a broad range of flux levels and wavelengths is rapidly becoming a new frontier of astronomical research. We describe here briefly the...
A Galaxy at z = 6.545 and Constraints on the Epoch of Reionization (2004)
Stern, Daniel, Yost, Sarah A., Eckart, Megan E., Harrison, Fiona A., Helfand, David J., Djorgovski, S. G., ...
We report the discovery of a Lyman-alpha-emitting galaxy at redshift z=6.545 serendipitously identified in the course of spectroscopic follow-up of hard X-ray sources on behalf of the Serendipitous...
Lopes, P. A. A., De Carvalho, R. R., Gal, R. R., Djorgovski, S. G., Odewahn, S. C., Mahabal, A. A., ...
We present an optically selected galaxy cluster catalog from ~ 2,700 square degrees of the Digitized Second Palomar Observatory Sky Survey (DPOSS), spanning the redshift range 0.1 < z < 0.5,...
Direct Constraints on the Properties and Evolution of Dark Energy (2004)
Daly, Ruth A., Djorgovski, S. G.
We describe a method to derive the expansion and acceleration rates directly from the data, without the need for the specification of a theory of gravity, and without adopting an a priori...
Daly, Ruth A., Djorgovski, S. G.
One of the goals of current cosmological studies is the determination of the expansion and acceleration rates of the universe as functions of redshift, and the determination of the properties of the...
Daly, Ruth A., Djorgovski, S. G.
Understanding of the nature of dark energy, which appears to drive the expansion of the universe, is one of the central problems of physical cosmology today. In an earlier paper [Daly & Djorgovski...
Piotto, Giampaolo, De Angeli, Francesca, King, Ivan R., Djorgovski, S. G., Bono, Giuseppe, Cassisi, Santi, ...
We discuss the main properties of the Galactic globular cluster (GC) blue straggler stars (BSS), as inferred from our new catalog containing nearly 3000 BSS. The catalog has been extracted from the...
Palomar-QUEST: A case study in designing sky surveys in the VO era (2004)
Graham, Matthew J., Williams, Roy, Djorgovski, S. G., Mahabal, Ashish, Baltay, Charles, Rabinowitz, Dave, ...
The advent of wide-area multicolour synoptic sky surveys is leading to data sets unprecedented in size, complexity and data throughput. VO technology offers a way to exploit these to the full but...
Piotto, Giampaolo, De Angeli, Francesca, King, Ivan R., Djorgovski, S. G., Bono, Giuseppe, Cassisi, Santi, ...
We discuss the main properties of the Galactic globular cluster (GC)blue straggler stars (BSSs), as inferred from our new catalog containingnearly 3000 BSSs. The catalog has been extracted from...
Hyperatlas: A New Framework for Image Federation (2003)
Williams, R. D., Djorgovski, S. G., Feldmann, M. T., Jacob, J. C.
Hyperatlas is an open standard intended to facilitate the large-scale federation of image-based data. The subject of hyperatlas is the space of sphere-to-plane projection mappings (the FITS-WCS...
Atlasmaker: A Grid-based Implementation of the Hyperatlas (2003)
Williams, R. D., Djorgovski, S. G., Feldmann, M. T., Jacob, J. C.
The Atlasmaker project is using Grid technology, in combination with NVO interoperability, to create new knowledge resources in astronomy. The product is a multi-faceted, multi-dimensional,...
The bright optical afterglow of the nearby gamma-ray burst of 29 March 2003 (2003)
Price, P. A., Fox, D. W., Kulkarni, S. R., Peterson, B. A., Schmidt, B. P., Soderberg, A. M., ...
Many past studies of cosmological gamma-ray bursts (GRBs) have been limited because of the large distance to typical GRBs, resulting in faint afterglows. There has long been a recognition that a...
Discovery of a Clustered Quasar Pair at z ~ 5: Biased Peaks in Early Structure Formation (2003)
Djorgovski, S. G., Stern, D., Mahabal, A., Brunner, R.
We report a discovery of a quasar at z = 4.96 +- 0.03 within a few Mpc of the quasar SDSS 0338+0021 at z = 5.02 +- 0.02. The newly found quasar has the SDSS i and z magnitudes of ~ 21.2, and an...
New Damped Lya Metallicities from ESI Spectroscopy of Five Palomar Sky Survey Quasars (2003)
Prochaska, Jason X., Castro, Sandra, Djorgovski, S. G.
This paper presents chemical abundance measurements for 12 new z>3 damped Lya systems discovered toward five quasars from the Palomar Sky Survey. We determine HI column densities from profile fits to...
The Age-Metallicity Relation of the Universe in Neutral Gas: The First 100 Damped Lya Systems (2003)
Prochaska, Jason X., Gawiser, Eric, Wolfe, Arthur M., Castro, Sandro, Djorgovski, S. G.
We present accurate metallicity measurements for 121 damped Lya systems at 0.5
Daly, Ruth A., Djorgovski, S. G.
Determination of the expansion and acceleration history of the universe is one of the fundamental goals of cosmology. Detailed measurements of these rates as a function of redshift can provide new...
A Molecular Einstein Ring: Imaging a Starburst Disk Surrounding a Quasi-Stellar Object (2003)
Carilli, C. L., Lewis, G. F., Djorgovski, S. G., Mahabal, A., Cox, P., Bertoldi, F., ...
Images of the CO 2-1 line emission, and the radio continuum emission, from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter...
The First Two Host Galaxies of X-ray Flashes: XRF 011030 and XRF 020427 (2003)
Bloom, J. S., Fox, D., Van Dokkum, P. G., Kulkarni, S. R., Berger, E., Djorgovski, S. G., ...
Given the paucity of empirical constraints, the nature of the newly-recognized phenomena called X-Ray Flashes (XRFs) has been an open question. However, with the recent detections of radio and X-ray...
Correlations of Globular Cluster Properties: Their Interpretations and Uses (2003)
Djorgovski, S. G., Cote, P., Meylan, G., Castro, S., Federici, L., Parmeggiani, G., ...
Correlations among the independently measured physical properties of globular clusters (GCs) can provide powerful tests for theoretical models and new insights into their dynamics, formation, and...
Cosmological Uses of Gamma-Ray Bursts (2003)
Djorgovski, S. G., Kulkarni, S. R., Frail, D. A., Harrison, F. A., Bloom, J. S., Berger, E., ...
Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are starting to provide interesting or even unique new insights in observational cosmology. GRBs represent a new way of...
The Cosmic Gamma-Ray Bursts and Their Host Galaxies in a Cosmological Context (2003)
Djorgovski, S. G., Kulkarni, S. R., Frail, D. A., Harrison, F. A., Bloom, J. S., Berger, E., ...
Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are now starting to provide interesting or even unique new insights in observational cosmology. Observed GRB host galaxies have a...
Gal, R. R., De Carvalho, R. R., Lopes, P. A. A., Djorgovski, S. G., Brunner, R. J., Mahabal, A. A., ...
We present a new, objectively defined catalog of candidate galaxy clusters based on the galaxy catalogs from the Digitized Second Palomar Observatory Sky Survey (DPOSS). This cluster catalog, derived...
Hubble Space Telescope and Ground-Based Optical and Ultraviolet Observations of GRB010222 (2003)
Galama, T. J., Reichart, D., Brown, T. M., Kimble, R. A., Price, P. A., Berger, E., ...
We report on Hubble Space Telescope WFPC2 optical and STIS near ultraviolet MAMA observations, and ground-based optical observations of GRB010222, spanning 15 hrs to 71 days. The observations are...
Hyperatlas: A New Framework for Image Federation (2003)
Williams, R.D., Djorgovski, S.G., Feldmann, M.T., Jacob, J.C.
Hyperatlas is an open standard intended to facilitate the large-scale federation of image-based data. The subject of hyperatlas is the space of sphere-to-plane projection mappings (the FITS-WCS...
A Molecular Einstein Ring: Imaging a Starburst Disk Surrounding a Quasi-Stellar Object (2003)
Carilli, C. L., Lewis, G. F., Djorgovski, S. G., Mahabal, A., Cox, P., Bertoldi, F., ...
Images of the CO 2-1 line emission, and the radio continuum emission, from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter...
A Molecular Einstein Ring: Imaging a Starburst Disk Surrounding a Quasi-Stellar Object (2003)
Carilli, C. L., Lewis, G. F., Djorgovski, S. G., Mahabal, A., Cox, P., Bertoldi, F., ...
Images of the CO 2-1 line emission, and the radio continuum emission, from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter...
A molecular Einstein ring : imaging a starburst disk surrounding a quasi-stellar object (2003)
Carilli, C. L., Lewis, G. F., Djorgovski, S. G., Mahabal, A., Cox, P., Bertoldi, F., ...
Images of the molecular CO 2-1 line emission and the radio continuum emission from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322 + 1944 reveal an Einstein ring with a...
THE DIGITIZED SECOND PALOMAR OBSERVATORY SKY SURVEY (DPOSS). III. STAR-GALAXY SEPARATION (2003)
S. C. Odewahn, R. R. Gal, S. G. Djorgovski, R. Brunner, A. Mahabal, ...
We discuss object classification for a multicolor survey of high-latitude fields from the Digitized Second Palomar Observatory Sky Survey (DPOSS) and the resulting Palomar-Norris Sky Catalog. Two...
Bloom, J. S., Berger, E., Kulkarni, S. R., Djorgovski, S. G., Frail, D. A.
Using the Echellete Spectrograph Imager (ESI) on the Keck II 10-m telescope we have measured the redshifts of the host galaxies of gamma-ray bursts GRB 990506 and GRB 000418, z=1.30658 +/- 0.00004...
Cosmic Gamma-Ray Bursts, Their Afterglows, and Their Host Galaxies (2002)
Hurley, K., Sari, R., Djorgovski, S. G.
This is a review article for the book "Compact Stellar X-Ray Sources", Editors W. Lewin and M. van der Klis, to be published by Cambridge University Press in 2003. It covers the phenomenology of...
Topic maps for custom viewing of data (2002)
Mahabal, A A, Djorgovski, S G, Williams, R E, Brunner, R
A Topic Map is a structured network of hyperlinks that points into an information pool. Topic Maps have an existence independent of the information pool and hence different Topic Maps can form...
The Infrared Counterpart of the Microquasar GRS 1758-258 (2002)
Rothstein, D. M., Eikenberry, S. S., Chatterjee, S., Egami, E., Djorgovski, S. G., Heindl, W. A.
We present revised infrared (2.2 micron) astrometry of the field containing the Galactic microquasar GRS 1758-258, using observations at the Keck I 10-m telescope. We find three candidates for the...
The Digitized Second Palomar Observatory Sky Survey (DPOSS) II: Photometric Calibration (2002)
Gal, R. R., De Carvalho, R. R., Odewahn, S. C., Djorgovski, S. G., Mahabal, A. A., Brunner, R. J., ...
We present the photometric calibration technique for the Digitized Second Palomar Observatory Sky Survey (DPOSS), used to create seamless catalogs of calibrated objects over large sky areas. After...
Challenges for Cluster Analysis in a Virtual Observatory (2002)
Djorgovski, S. G., Brunner, R., Mahabal, A., Williams, R., Granat, R., Stolorz, P.
There has been an unprecedented and continuing growth in the volume, quality, and complexity of astronomical data sets over the past few years, mainly through large digital sky surveys. Virtual...
The Roles of Small Telescopes in a Virtual Observatory Environment (2002)
The advent of the Virtual Observatory (VO) concept signals a pradigm shift in the way astronomy will be done in the era of information abundance and ubiquitous networking. Small telescopes will be...
Discovery of GRB 020405 and its Late Red Bump (2002)
Price, P. A., Kulkarni, S. R., Berger, E., Fox, D. W., Bloom, J. S., Djorgovski, S. G., ...
We present the discovery of GRB 020405 made with the Inter-Planetary Network (IPN). With a duration of 60 s, the burst appears to be a typical long duration event. We observed the 75-square acrminute...
Berger, E., Kulkarni, S. R., Bloom, J. S., Price, P. A., Fox, D. W., Frail, D. A., ...
We present ground-based optical observations of GRB 020124 starting 1.6 hours after the burst, as well as subsequent Very Large Array (VLA) and Hubble Space Telescope (HST) observations. The optical...
GRB 010921: Strong Limits on an Underlying Supernova from HST (2002)
Price, P. A., Kulkarni, S. R., Schmidt, B. P., Galama, T. J., Bloom, J. S., Berger, E., ...
GRB 010921 was the first HETE-2 GRB to be localized via its afterglow emission. The low-redshift of the host galaxy, z=0.451, prompted us to undertake intensive multi-color observations with the...
Piotto, G., King, I. R., Djorgovski, S. G., Sosin, C., Zoccali, M., Saviane, I., ...
We present the complete photometric database and the color-magnitude diagrams for 74 Galactic globular clusters observed with the HST/WFPC2 camera in the F439W and F555W bands. A detailed discussion...
Time-Dependent Optical Spectroscopy of GRB 010222: Clues to the GRB Environment (2002)
Mirabal, N., Halpern, J. P., Kulkarni, S. R., Castro, S., Bloom, J. S., Djorgovski, S. G., ...
We present sequential optical spectra of the afterglow of GRB 010222 obtained one day apart using the Low Resolution Imaging Spectrometer (LRIS) and the Echellette Spectrograph and Imager (ESI) on...
The Broadband Afterglow of GRB980329 (2002)
Yost, S. A., Frail, D. A., Harrison, F. A., Sari, R., Reichart, D., Bloom, J. S., ...
We present radio observations of the afterglow of the bright gamma-ray burst GRB980329 made between one month and several years after the burst, a re-analysis of previously published submillimeter...
GRB 011121: A Massive Star Progenitor (2002)
Price, P. A., Berger, E., Reichart, D. E., Kulkarni, S. R., Subrahmanyan, R., Wark, R. M., ...
Of the cosmological gamma-ray bursts, GRB 011121 has the lowest redshift, z=0.36. More importantly, the multi-color excess in the afterglow detected in the Hubble Space Telescope (HST) light curves...
Palomar 13: An Unusual Stellar System in the Galactic Halo (2002)
Cote, Patrick, Djorgovski, S. G., Meylan, Georges, Castro, S., McCarthy, J. K.
We have measured Keck/HIRES radial velocities for 30 candidate red giants in the direction of Palomar 13: an object traditionally cataloged as a compact, low-luminosity globular cluster. From a...
Detection of a supernova signature associated with GRB 011121 (2002)
Bloom, J. S., Kulkarni, S. R., Price, P. A., Reichart, D., Galama, T. J., Schmidt, B. P., ...
Using observations from an extensive monitoring campaign with the Hubble Space Telescope we present the detection of an intermediate-time flux excess which is redder in color relative to the...
CO and Dust in PSS2322+1944 at a redshift of 4.12 (2002)
Cox, P., Omont, A., Djorgovski, S. G., Bertoldi, F., Pety, J., Carilli, C. L., ...
Using the IRAM interferometer we have detected J=4-3 and 5-4 CO line emission toward the radio quiet quasar PSS2322+1944. At a redshift of z_CO=4.1199 this is the fourth and strongest detection of CO...
GRB 010921: Discovery of the First HETE Afterglow (2002)
Price, P. A., Kulkarni, S. R., Berger, E., Djorgovski, S. G., Frail, D. A., Mahabal, A., ...
We report the discovery of the optical and radio afterglow of GRB 010921, the first gamma-ray burst afterglow to be found from a localization by the High Energy Transient Explorer (HETE) satellite....
Atlasmaker: A Grid-based Implementation of the Hyperatlas (2002)
Williams, R.D., Djorgovski, S.G., Feldmann, M.T., Jacob, J.C.
The Atlasmaker project is using Grid technology, in combination with NVO interoperability, to create new knowledge resources in astronomy. The product is a multi-faceted, multi-dimensional,...
CO and Dust in PSS2322+1944 at a redshift of 4.12 (2002)
Cox, P., Omont, A., Djorgovski, S. G., Bertoldi, F., Pety, J., Carilli, C. L., ...
Using the IRAM interferometer we have detected J=4-3 and 5-4 CO line emission toward the radio quiet quasar PSS2322+1944. At a redshift of z_CO=4.1199 this is the fourth and strongest detection of CO...
CO and Dust in PSS2322+1944 at a redshift of 4.12 (2002)
Cox, P., Omont, A., Djorgovski, S. G., Bertoldi, F., Pety, J., Carilli, C. L., ...
Using the IRAM interferometer we have detected J=4-3 and 5-4 CO line emission toward the radio quiet quasar PSS2322+1944. At a redshift of z_CO=4.1199 this is the fourth and strongest detection of CO...
Imaging low-order CO emission from the z = 4.12 quasi-stellar object PSS J2322+1944 (2002)
Carilli, C. L., Cox, P., Bertoldi, F., Menten, K. M., Omont, A., Djorgovski, S. G., ...
We present observations of CO (1-0) and CO (2-1) emission from the z = 4.12 quasi-stellar object (QSO) PSS J2322+1944 using the Very Large Array.(1) The CO emission is extended on a spatial scale of...
CO and dust in PSS 2322+1944 at a redshift of 4.12 (2002)
Cox, P., Omont, A., Djorgovski, S. G., Bertoldi, F., Pety, J., Carilli, C. L., ...
Using the IRAM interferometer we have detected J=4-->3 and 5-- >4 CO line emission toward the radio quiet quasar PSS 2322+1944. At a redshift of z(CO)=4.1199 this is the fourth and strongest...
GRB 010222 : a burst within a starburst (2002)
Frail, D. A., Bertoldi, F., Moriarty-Schieven, G. H., Berger, E., Price, P. A., Bloom, J. S., ...
We present millimeter- and submillimeter-wavelength observations and near-infrared K-band imaging toward the bright gamma-ray burst GRB 010222. Over seven different epochs, a constant source was...
Keck Spectroscopy and HST Imaging of GRB 000926: Probing a Host Galaxy at z = 2. 038 (2001)
Castro, S., Galama, T. J., Harrison, F. A., Holtzman, J. A., Bloom, J. S., Djorgovski, S. G., ...
We present early-time Keck spectroscopic observations and late-time Hubble Space Telescope (HST) imaging of GRB 000926. The HST images show a small offset between the optical transient and the...
The Unusually Long Duration Gamma-ray Burst GRB 000911 (2001)
Price, P. A., Berger, E., Kulkarni, S. R., Djorgovski, S. G., Fox, D. W., Mahabal, A., ...
Of all the well localized gamma-ray bursts, GRB 000911 has the longest duration (T_90 ~ 500 s), and ranks in the top 1% of BATSE bursts for fluence. Here, we report the discovery of the afterglow of...
Topic Maps as a Virtual Observatory tool (2001)
Mahabal, A., Djorgovski, S. G., Brunner, R., Williams, R.
One major component of the VO will be catalogs measuring gigabytes and terrabytes if not more. Some mechanism like XML will be used for structuring the information. However, such mechanisms are not...
GRB 010222: A Burst Within a Starburst (2001)
Frail, D. A., Bertoldi, F., Moriarty-Schieven, G. H., Berger, E., Price, P. A., Bloom, J. S., ...
We present millimeter and submillimeter wavelength observations and near-infrared K-band imaging toward the bright gamma-ray burst GRB 010222. Over seven epochs the flux density of the source was...
Exploration of Parameter Spaces in a Virtual Observatory (2001)
Djorgovski, S. G., Mahabal, A., Brunner, R., Williams, R., Granat, R., Curkendall, D., ...
Like every other field of intellectual endeavor, astronomy is being revolutionised by the advances in information technology. There is an ongoing exponential growth in the volume, quality, and...
On the Threshold of the Reionization Epoch (2001)
Djorgovski, S. G., Castro, S. M., Stern, D., Mahabal, A.
Discovery of the cosmic reionization epoch would represent a significant milestone in cosmology. We present Keck spectroscopy of the quasar SDSS 1044-0125, at z = 5.73. The spectrum shows a dramatic...
The GRB Host Galaxies and Redshifts (2001)
Djorgovski, S. G., Kulkarni, S. R., Bloom, J. S., Frail, D. A., Harrison, F. A., Galama, T. J., ...
Observations of GRB host galaxies and their environments in general can provide valuable clues about the nature of progenitors. Bursts are associated with faint, ~ 25 mag, galaxies at cosmological...
The Afterglow and the Host Galaxy of the Dark Burst GRB 970828 (2001)
Djorgovski, S. G., Frail, D. A., Kulkarni, S. R., Bloom, J. S., Odewahn, S. C., Diercks, A.
GRB 970828 was the first well-localized gamma-ray burst (GRB) X-ray afterglow for which no optical afterglow was found despite a prompt, deep search down to R_lim ~ 24.5 mag. We report the discovery...
The Cosmic Gamma-Ray Bursts (2001)
Djorgovski, S. G., Frail, D. A., Kulkarni, S. R., Sari, R., Bloom, J. S., Galama, T. J., ...
Cosmic gamma-ray bursts are one of the great frontiers of astrophysics today. They are a playground of relativists and observers alike. They may teach us about the death of stars and the birth of...
Mayall II = G1 in M31: Giant Globular Cluster or Core of a Dwarf Elliptical Galaxy ? (2001)
Meylan, G., Sarajedini, A., Jablonka, P., Djorgovski, S. G., Bridges, T., Rich, R. M.
(Abridged version) Mayall II = G1 is one of the brightest globular clusters belonging to M31, the Andromeda galaxy. Our observations with HST/WFPC2 provide data for the (I vs. V-I) and (V vs. V-I)...
Deep Infrared Imaging of the Microquasars 1E1740-2942 and GRS 1758-258 (2001)
Eikenberry, S. S., Fischer, W. J., Egami, E., Djorgovski, S. G.
We present deep infrared ($2.2 \mu$m) imaging of the Galactic microquasars 1E1740-2942 and GRS 1758-258 using the Keck-I 10-meter telescope in June 1998. The observations were taken under excellent...
The afterglows of gamma-ray bursts (2001)
Kulkarni, S. R., Berger, E., Bloom, J. S., Chaffee, F., Diercks, A., Djorgovski, S. G., ...
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at...
Harrison, F. A., Yost, S. A., Sari, R., Berger, E., Axelrod, T., ...
GRB 000926 has one of the best-studied afterglows to-date, with multiple X-ray observations, as well as extensive multi-frequency optical and radio coverage. Broadband afterglow observations,...
Beaming in Gamma-Ray Bursts: Evidence for a Standard Energy Reservoir (2001)
Frail, D. A., Kulkarni, S. R., Sari, R., Djorgovski, S. G., Bloom, J. S., Galama, T. J., ...
Gamma-ray bursts (GRBs) are the most brilliant objects in the Universe but efforts to estimate the total energy released in the explosion -- a crucial physical quantity -- have been stymied by their...
Exploration of Large Digital Sky Surveys (2000)
Djorgovski, S. G., Brunner, R. J., Mahabal, A. A., Odewahn, S. C., De Carvalho, R. R., Gal, R. R., ...
We review some of the scientific opportunities and technical challenges posed by the exploration of the large digital sky surveys, in the context of a Virtual Observatory (VO). The VO paradigm will...
Searches for Rare and New Types of Objects (2000)
Djorgovski, S. G., Mahabal, A. A., Brunner, R. J., Gal, R. R., Castro, S., De Carvalho, R. R., ...
Systematic exploration of the observable parameter space, covered by large digital sky surveys spanning a range of wavelengths, will be one of the primary modes of research with a Virtual Observatory...
Multi-Color Observations of the GRB000926 Afterglow (2000)
Price, P. A., Harrison, F. A., Galama, T. J., Reichart, D. E., Axelrod, T. S., Berger, E. J., ...
We present multi-color light-curves of the optical afterglow of GRB 000926. Beginning ~1.5 days after the burst, the light-curves of this GRB steepen measurably. The existence of such achromatic...
Luminosity function of clusters of galaxies (2000)
Paolillo, M., Andreon, S., Longo, G., Puddu, E., Gal, R. R., Scaramella, R., ...
The composite galaxy luminosity function (hereafter LF) of 39 Abell clusters of galaxies is derived by computing the statistical excess of galaxy counts in the cluster direction with respect to...
The Digital Sky Project: Prototyping Virtual Observatory Technologies (2000)
Brunner, R. J, Prince, T., Good, J., Handley, T., Lonsdale, C., Djorgovski, S. G.
Astronomy is entering a new era as multiple, large area, digital sky surveys are in production. The resulting datasets are truly remarkable in their own right; however, a revolutionary step arises in...
Margoniner, V. E., De Carvalho, R. R., Gal, R. R., Djorgovski, S. G.
We examine the Butcher-Oemler effect and its cluster richness dependence in the largest sample studied to date: 295 Abell clusters. We find a strong correlation between cluster richness and the...
Exploring the Multi-Wavelength, Low Surface Brightness Universe (2000)
Brunner, R. J., Djorgovski, S. G., Gal, R. R., Mahabal, A. A., Odewahn, S. C.
Our current understanding of the low surface brightness universe is quite incomplete, not only in the optical, but also in other wavelength regimes. As a demonstration of the type of science which is...
Bloom, J. S., Kulkarni, S. R., Djorgovski, S. G.
We present a comprehensive study to measure the locations of gamma-ray bursts (GRBs) relative to their host galaxies. In total, we find the offsets of 20 long-duration GRBs from their apparent host...
The Luminosity Function of 81 Abell Clusters from the CRoNaRio catalogues (2000)
Piranomonte, S., Paolillo, M., Andreon, S., Longo, G., Puddu, E., Scaramella, R., ...
We present the composite luminosity function (hereafter LF) of galaxies for 81 Abell clusters studied in our survey of the Northern Hemisphere, using DPOSS data processed by the CRoNaRio...
The Luminosity Function of 80 Abell Clusters from the CRoNaRio catalogues (2000)
Piranomonte, S., Paolillo, M., Longo, G., Andreon, S., Puddu, E., Scaramella, R., ...
We present the composite luminosity function (hereafter LF) of galaxies for 80 Abell clusters studied in our survey of the Northern Hemisphere, using DPOSS data in the framework of the CRoNaRio...
The afterglows of gamma-ray bursts (2000)
Kulkarni, S. R., Berger, E., Bloom, J. S., Chaffee, F., Diercks, A., Djorgovski, S. G., ...
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long-duration GRBs lie at...
Djorgovski, S. G., Bloom, J. S., Kulkarni, S. R.
We present optical and near-IR identification and spectroscopy of the host galaxy of GRB 980613. The burst was apparently associated with the optically (restframe UV) brightest component of a system...
The redshift and the ordinary host galaxy of GRB 970228 (2000)
Bloom, J. S., Djorgovski, S. G., Kulkarni, S. R.
The gamma-ray burst of 28 February 1997 (GRB 970228) ushered in the discovery of the afterglow phenomenon. Despite intense study of the host galaxy, however, the nature of the host and the distance...
Mass-to-Light Ratios of Groups and Clusters of Galaxies (2000)
Hradecky, V., Jones, C., Donnelly, R. H., Djorgovski, S. G., Gal, R. R., Odewahn, S. C.
We constrain the mass-to-light ratios, gas mass fractions, baryon mass fractions and the ratios of total to luminous mass for a sample of eight nearby relaxed galaxy groups and clusters: A262, A426,...
The afterglows of gamma-ray bursts (2000)
Kulkarni, S. R., Berger, E., Bloom, J. S., Chaffee, F., Diercks, A., Djorgovski, S. G., ...
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at...
The Rapidly Fading Afterglow from the Gamma-Ray Burst of 1999 May 6 (2000)
Taylor, G. B., Bloom, J. S., Frail, D. A., Kulkarni, S. R., Djorgovski, S. G., Jacoby, B. A.
We report on the discovery of the radio afterglow from the gamma-ray burst (GRB) of 1999 May 6 (GRB 990506) using the Very Large Array (VLA). The radio afterglow was detected at early times (1.5...
The Palomar Abell Cluster Optical Survey I: Photometric Redshifts for 431 Abell Clusters (2000)
Gal, R. R., De Carvalho, R. R, Brunner, R., Odewahn, S. C., Djorgovski, S. G.
This paper presents photometric redshifts for 431 Abell clusters imaged as part of the Palomar Abell Cluster Optical Survey (PACOS), of which 236 are new redshi fts. We have obtained moderately deep,...
On the helium content of Galactic globular clusters via the R parameter (2000)
Zoccali, M., Cassisi, S., Bono, G., Piotto, G., Rich, R. M., Djorgovski, S. G.
We estimate the empirical R parameter in 26 Galactic Globular Clusters covering a wide metallicity range, imaged by WFPC2 on board the HST. The improved spatial resolution permits a large fraction of...
Use of DPOSS data to study globular cluster halos: an application to M 92 (2000)
Testa, V., Zaggia, S. R., Andreon, S., Longo, G., Scaramella, R., Djorgovski, S. G., ...
We exploited the large areal coverage offered by the DPOSS to analyze the outermost regions of the galactic globular cluster M 92. Two independent photometric reduction programs (SKICAT and DAOPHOT)...
The afterglows of gamma-ray bursts (2000)
Kulkarni, S. R., Berger, E., Bloom, J. S., Chaffee, F., Diercks, A., Djorgovski, S. G., ...
Gamma-ray burst astronomy has undergone a revolution in the last three years, spurred by the discovery of fading long-wavelength counterparts. We now know that at least the long duration GRBs lie at...
Radio Properties of z>4 Optically-Selected Quasars (2000)
Stern, Daniel, Djorgovski, S. G., Perley, R. A., DeCarvalho, Reinaldo R., Wall, J. V.
We report on two programs to address differential evolution between the radio-loud and radio-quiet quasar populations at high (z>4) redshift. Both programs entail studying the radio properties of...
Young Stars and Nonstellar Emission in the Aligned Radio Galaxy 3C 256 (1999)
Simpson, C, Eisenhardt, P, Armus, L, Chokshi, A, Dickinson, M, Djorgovski, S. G, ...
We present ground-based images of the z=1.824 radio galaxy 3C 256 in the standard BVRIJHK filters and an interference filter centered at 8800 Å, a Hubble Space Telescope image in a filter dominated...
Three-micron imaging of the Hubble Deep Field (1999)
Hogg, David W., Neugebauer, Gerry, Cohen, Judith G., Dickinson, Mark, Djorgovski, S. G., Matthews, Keith, ...
Images of the Hubble Deep Field at 3.2 um, taken with the 10-m Keck Telescope, are presented. The images cover a total area of ~2.5 arcmin^2. To a 5-sigma limit of [3.2](total)=17.5 mag...
High-Redshift Quasars as Probes of Galaxy and Cluster Formation (1999)
Quasars at large redshifts provide a powerful probe of structure formation in the early universe. Several arguments suggest that the formation of ellipticals and massive bulges may have involved an...
The Northern Sky Optical Cluster Survey I: Detection of Galaxy Clusters in DPOSS (1999)
Gal, R. R., DeCarvalho, R. R., Odewahn, S. C., Djorgovski, S. G., Margoniner, V. E.
The Northern Sky Optical Cluster Survey is a project to create an objective catalog of galaxy clusters over the entire high-galactic-latitude Northern sky, with well understood selection criteria. We...
The Radio Afterglow and the Host Galaxy of the X-Ray Rich GRB 981226 (1999)
Frail, D. A., Kulkarni, S. R., Bloom, J. S., Djorgovski, S. G., Gorjian, V., Gal, R. R., ...
We report the discovery of a radio transient VLA 232937.2-235553, coincident with the proposed X-ray afterglow for the gamma-ray burst GRB 981226. This GRB has the highest ratio of X-ray to gamma-ray...
The Luminosity Function of 24 Abell Clusters from the CRoNaRio catalogues (1999)
Paolillo, M., Andreon, S., Longo, G., Puddu, E., Piranomonte, S., Scaramella, R., ...
We present the composite luminosity function of galaxies for 24 Abell clusters studied in our survey of the Northern Hemisphere, using DPOSS data in the framework of the CRoNaRio collaboration. Our...
An automatic procedure to extract galaxy clusters from CRoNaRio catalogs (1999)
Puddu, E., Andreon, S., Longo, G., Paolillo, M., Scaramella, R., Testa, V., ...
We present preliminary results of a simple peak finding algorithm applied to catalogues of galaxies, extracted from the Second Palomar Sky Survey in the framework of the CRoNaRio project. All...
The Multiplicity Function of groups of galaxies from CRoNaRio catalogues (1999)
De Filippis, E., Longo, G., Andreon, S., Scaramella, R., Testa, V., De Carvalho, R. R., ...
The projected multiplicity function of galaxies gives (per square degree) the density of galaxy aggregates formed by N members. We use the CRoNaRio matched catalogues to derive the low N (N
NICMOS Imaging of High-Redshift Radio Galaxies (1999)
Zirm, A., Dey, A., Dickinson, M., McCarthy, P. J., Eisenhardt, P., Djorgovski, S. G., ...
We have obtained near-infrared (1.6 micron) images of 11 powerful 3CR radio galaxies at redshifts 0.8 < z < 1.8 using NICMOS on board HST. The high angular resolution permits a detailed study of...
The Clustering of Faint Galaxies on Small Angular Scales (1999)
Brainerd, Tereasa G., Law, Casey J., Brauher, James, Djorgovski, S. G., Banas, Ken
We present a preliminary measurement of the angular clustering of faint ($R \le 25$) field galaxies in which we concentrate on the behavior of $w(\theta)$ on small angular scales ($\theta \ls 10''$)....
Quasar-Marked Protoclusters and Biased Galaxy Formation (1999)
Djorgovski, S. G., Odewahn, S. C., Gal, R. R., Brunner, R., De Carvalho, R. R.
We report on the current status of our search for protoclusters around quasars at z > 4. While the search is still very incomplete, clustered companion galaxies are found in virtually every case...
Behr, Bradford B., Djorgovski, S. G., Cohen, Judith G., McCarthy, James K., Cote, Patrick, Piotto, Giampaolo, ...
We have determined the projected rotational velocities of thirteen blue horizontal-branch (BHB) stars in the globular cluster M13 via rotational broadening of metal absorption lines. Our sample spans...
Young stars and non-stellar emission in the aligned radio galaxy 3C 256 (1999)
Simpson, Chris, Eisenhardt, Peter, Armus, Lee, Chokshi, Arati, Dickinson, Mark, Djorgovski, S. G., ...
We present ground-based images of the z=1.824 radio galaxy 3C 256 in the standard BVRIJHK filters and an interference filter centered at 8800A, a Hubble Space Telescope image in a filter dominated by...
Photometric Redshifts for DPOSS Galaxy Clusters at z (1999)
Gal, R. R., Odewahn, S. C., Djorgovski, S. G., Brunner, R., DeCarvalho, R. R.
We report on the creation of an unbiased catalog of galaxy clusters from the galaxy catalogs derived from the digitized POSS-II (DPOSS). Utilizing the g-r color information, we show that it is...
Optical and Radio Observations of the Afterglow from GRB990510: Evidence for a Jet (1999)
Harrison, F. A., Bloom, J. S., Frail, D. A., Sari, R., Kulkarni, S. R., Djorgovski, S. G., ...
We present multi-color optical and two-frequency radio observations of the bright SAX event, GRB 990510. The well-sampled optical decay, together with the radio observations are inconsistent with...
The unusual afterglow of GRB 980326: evidence for the gamma-ray burst/supernova connection (1999)
Bloom, J. S., Kulkarni, S. R., Djorgovski, S. G., Eichelberger, A. C., Cote, P., Blakeslee, J. P., ...
Cosmic gamma-ray bursts (GRBs) have been firmly established as one of the most powerful phenomena in the Universe, releasing electromagnetic energy approaching the rest-mass energy of a neutron star...
The afterglow, the redshift, and the extreme energetics of the gamma-ray burst 990123 (1999)
Kulkarni, S. R., Djorgovski, S. G., Odewahn, S. C., Bloom, J. S., Gal, R. R., Koresko, C. D., ...
Afterglow, or long-lived emission, has now been detected from about a dozen well-positioned gamma-ray bursts. Distance determinations made by measuring optical emission lines from the host galaxy, or...
The Host Galaxy of GRB 990123 (1999)
Bloom, J. S., Odewahn, S. C., Djorgovski, S. G., Koresko, C., Neugebauer, G., ...
We present deep images of the field of gamma-ray burst (GRB) 990123 obtained in a broad-band UV/visible bandpass with the Hubble Space Telescope, and deep near-infrared images obtained with the...
The Palomar Digital Sky Survey (DPOSS) (1998)
Djorgovski, S. G., Gal, R. R., Odewahn, S. C., De Carvalho, R. R., Brunner, R., Longo, G., ...
We describe DPOSS, a new digital survey of the northern sky, based on the POSS-II photographic sky atlas. The survey covers the entire sky north of delta = -3 deg in 3 bands, calibrated to the Gunn...
The Discovery and Broad-band Follow-up of the Transient Afterglow of GRB 980703 (1998)
Bloom, J. S., Frail, D. A., Kulkarni, S. R., Djorgovski, S. G., Halpern, J. P., Marzke, R. O., ...
We report on the discovery of the radio, infrared and optical transient coincident with an X-ray transient proposed to be the afterglow of GRB 980703. At later times when the transient has faded...
Spectroscopy of the Host Galaxy of the Gamma--Ray Burst 980703 (1998)
Djorgovski, S. G., Kulkarni, S. R., Bloom, J. S., Goodrich, R., Frail, D. A., Piro, L., ...
We present spectroscopic observations of the host galaxy of the gamma-ray burst (GRB) 980703. Several emission and absorption features are detected, making the redshift, z = 0.966, completely...
Systematic Variations in Age and Metallicity Along the Early-Type Galaxy Sequence (1998)
Pahre, M. A., Djorgovski, S. G., De Carvalho, R. R.
The form of the early-type galaxy scaling relation (the Fundamental Plane or FP) is a direct indicator of the underlying physical origins for the galaxy sequence. Observed properties of the FP...
The Host Galaxy of GRB 970508 (1998)
Bloom, J. S., Djorgovski, S. G., Kulkarni, S. R., Frail, D. A.
We present late-time imaging and spectroscopic observations of the optical transient (OT) of gamma-ray burst (GRB) 970508. Imaging observations roughly 200 and 300 days after the burst provide...
The Host Galaxy of the Gamma--Ray Burst 971214 (1998)
Odewahn, S. C., Djorgovski, S. G., Kulkarni, S. R., Dickinson, M., Frail, D. A., Ramaprakash, A. N., ...
We report on Hubble Space Telescope (HST) observations of the host galaxy of GRB 971214, about four months after the burst. The redshift of the proposed host galaxy at z=3.418, combined with optical...
Pahre, M. A., De Carvalho, R. R., Djorgovski, S. G.
The physical origins of the Fundamental Plane (FP) scaling relations are investigated for early-type galaxies observed at optical and near-infrared wavelengths. The slope for the FP is shown to...
Near-Infrared Imaging of Early-Type Galaxies III. The Near-Infrared Fundamental Plane (1998)
Pahre, M. A., Djorgovski, S. G., De Carvalho, R. R.
Near-infrared imaging data on 251 early-type galaxies in clusters and groups are used to construct the near-infrared Fundamental Plane (FP) r_eff ~ sigma_0^1.53 _eff^-0.79. The slope of the FP...
High-Redshift Quasars as Probes of Primordial Large-Scale Structure and Galaxy Formation (1998)
Several arguments suggest that quasars at z > 4 may be in the cores of future giant ellipticals, and forming at the very highest peaks of the primordial density field. A strong bias-driven primordial...
An Infrared Emission Line Galaxy at z = 2.43 (1998)
Beckwith, S. V. W., Thompson, D., Mannucci, F., Djorgovski, S. G.
An object discovered during an infrared survey of the field near the quasar B2 0149+33 has an emission line at 2.25$\mu$m that we interpret as H$\alpha$ at a redshift of 2.43. The K-band image shows...
BIMA and Keck Imaging of the Radio Ring PKS 1830-211 (1998)
Frye, B. L., Courbin, F., Broadhurst, T., Welch, W. J. W., Lidman, C., Magain, P., ...
We discuss BIMA (Berkeley Illinois Maryland Association) data and present new high quality optical and near-IR Keck images of the bright radio ring PKS 1830-211. Applying a powerful new deconvolution...
Image Deconvolution of the Radio Ring PKS 1830-211 (1998)
Courbin, F., Lidman, C., Frye, B., Magain, P., Broadhurst, T. J., Pahre, M. A., ...
New high quality Keck and ESO images of PKS 1830-211 are presented. Applying a powerful new deconvolution algorithm to these optical and infrared data, both images of the flat spectrum core of the...
Galaxy counterparts of high-redshift DLA systems (1997)
Our understanding of the nature of DLA systems at large redshifts, ostensibly progenitors of normal disk galaxies, depends critically on their direct identifications with galaxies, and the resulting...
Data-Mining a Large Digital Sky Survey: From the Challenges to the Scientific Results (1997)
Djorgovski, S. G., De Carvalho, R. R., Odewahn, S. C., Gal, R. R., Roden, J., Stolorz, P., ...
The analysis and an efficient scientific exploration of the Digital Palomar Observatory Sky Survey (DPOSS) represents a major technical challenge. The input data set consists of 3 Terabytes of pixel...
Globular Clusters Color-Magnitude Diagrams with HST (1997)
Sosin, C., Piotto, G., Djorgovski, S. G., King, I. R., Rich, R. M., Dorman, B., ...
In this paper we present the 13 B and V color-magnitude diagrams discussed by Piotto et al. in the same Procedings. The data have been collected with the WFPC2 camera on HST. We emphasize the...
HST Observations of High-Density Globular Clusters (1997)
Piotto, G., Sosin, C., King, I. R., Djorgovski, S. G., Rich, R. M., Dorman, B., ...
In this paper we present preliminary results from our HST project aimed at exploring the connection between the stellar dynamics and stellar evolution in the cores of high-density globular clusters....
Cataloging of the Digitized POSS-II, and Some Initial Scientific Results From It (1996)
Djorgovski, S. G., De Carvalho, R. R., Gal, R. R., Pahre, M. A., Scaramella, R., Longo, G.
We are conducting an effort to catalog all sources detected in the digitized POSS-II (DPOSS). This is now becoming an international collaboration including Caltech and the Observatories of Rome and...
Observational Constraints on the Origins of the Fundamental Plane (1996)
Pahre, M. A., Djorgovski, S. G.
We review the concept of the Fundamental Plane (FP), and present new results on the near-infrared FP. We show that the K-band FP differs both from the optical form and the virial expectation under...
Pahre, M. A., Djorgovski, S. G., Bechtold, J., Elston, R.
We report the detection, both in line and continuum emission, of a galaxy responsible for a damped Ly-alpha absorption (DLA) system at z=3.15 projected 2.3 arcsec from QSO 2233+131. The star...
The \mv vs \fe Calibration: I. HST Color-Magnitude Diagrams of 8 Globular Clusters in M 31 (1996)
Pecci, F. Fusi, Buonanno, R., Cacciari, C., Corsi, C. E., Djorgovski, S. G., Federici, L., ...
Color Magnitude Diagrams (CMDs) of individual stars in 8 Globular Clusters in M31 down to about 1 mag fainter (V$\sim 26.5$) than the Horizontal Branch have been obtained with the Hubble Space...
Sub-arcsecond imaging and spectroscopy of the radio-loud highly polarized quasar PKS 1610-771 (1996)
Courbin, F., Hutsemekers, D., Meylan, G., Magain, P., Djorgovski, S. G.
We report on imaging and spectroscopic observations of the radio-loud, highly polarized quasar PKS 1610-771 (z = 1.71). Our long-slit spectroscopy of the companion 4.55 arcseconds NW of the quasar...
Identification of a Galaxy Responsible for a High-Redshift Damped Ly-alpha Absorption System (1996)
Djorgovski, S. G., Pahre, M. A., Bechtold, J., Elston, R.
Galaxies believed to be responsible for damped Ly-alpha absorption (DLA) systems in the spectra of high-redshift quasars represent a viable population of progenitors of normal disk galaxies. They...
Pahre, M. A., Djorgovski, S. G., De Carvalho, R. R.
We use the intercept of the elliptical galaxy radius--surface brightness (SB) relation at a fixed metric radius as the standard condition for the Tolman SB test of the universal expansion. We use...
The Near-Infrared Fundamental Plane of Elliptical Galaxies (1995)
Pahre, M. A., Djorgovski, S. G., De Carvalho, R. R.
We present results from a near-infrared $K$-band imaging survey of 59 elliptical galaxies in five nearby clusters. We measure photometric parameters for each galaxy using surface photometry and draw...
A Near-Infrared Search for Line Emission from Protogalaxies Using the W. M. Keck Telescope (1995)
Pahre, M. A., Djorgovski, S. G.
We present the first results from a near-infrared narrow-band search for primeval galaxies (PGs) using the Keck 10~m telescope. We have targeted our fields for three QSOs and one radio galaxy at...
Clustering Analysis Algorithms and Their Applications to Digital POSS-II Catalogs (1995)
De Carvalho, S. G. Djorgovski, N. Weir, U. Fayyad, K. Cherkauer, J. Roden, ...
. We report on the preliminary results of experiments using a Bayesian cluster method to cluster objects present in photographic images of the POSS-II. Our goal is to explore the power of...
Myers, S.T., Fassnacht, C.D., Djorgovski, S.G., Neugebauer, G., Pearson, T.J., Readhead, A.C.S., ...
Surface photometry of early-type galaxies / (1985)
Thesis (Ph. D.)--University of California, Berkeley, 1985.
Surface photometry of early-type galaxies. (1985)
Thesis--University of California, Berkeley, 1985.