Scientific Commons: W. L. Freedman

Optical observations of the Type Ia supernova (SN Ia) 2005bl in NGC 4070, obtained from -6 to +66 d with respect to the B-band maximum, are presented. The photometric evolution is characterised by...

A Study of the Type Ia/IIn Supernova 2005gj from X-ray to the Infrared: Paper I (2007)

Prieto, J. L., Garnavich, P. M., Phillips, M. M., DePoy, D. L., Parrent, J., Pooley, D., ...

We present extensive ugrizYHJK photometry and optical spectroscopy of SN 2005gj obtained by the SDSS-II and CSP Supernova Projects, which give excellent coverage during the first 150 days after the...

The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations? (2006)

Phillips, M. M., Li, W., Frieman, J. A., Blinnikov, S. I., DePoy, D., Prieto, J. L., ...

We present extensive u'g'r'i'BVRIYJHKs photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been...

SN 2005bf: A Possible Transition Event Between Type Ib/c Supernovae and Gamma Ray Bursts (2006)

Folatelli, Gaston, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...

We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first ~100 days following discovery. The u'g'BV light curves displayed a double-peaked morphology,...

Optical and Near-Infrared Observations of the Peculiar Type Ia Supernova 1999ac (2006)

Phillips, Mark M., Krisciunas, Kevin, Suntzeff, Nicholas B., Abraham, R. G., Beckett, M. G., Bonati, M., ...

We present 39 nights of optical photometry, 34 nights of infrared photometry, and 4 nights of optical spectroscopy of the Type Ia SN 1999ac. This supernova was discovered two weeks before maximum...

SN 2005bf: a possible transition event between type Ib/c supernovae and gamma-ray bursts (2006)

Folatelli, Gastón, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...

SN 2005bf: A Possible Transition Event Between Type Ib/c Supernovae and Gamma Ray Bursts (2005)

Folatelli, Gaston, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...

We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first ~100 days following discovery. The u'g'BV light curves displayed a double-peaked morphology,...

Corrections of Errors in `The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000 \AA. I, II, and III' (2005)

Bernstein, R. A., Freedman, W. L., Madore, B. F.

We correct errors in Bernstein, Freedman & Madore (2002abc), a series of papers in which we described observations of the optical extragalactic background light (EBL). These errors pertain to the...

The Discovery of the Optical and Near-IR Afterglows of the First Swift Gamma-Ray Bursts (2005)

Berger, E., Fox, D. B., Kulkarni, S. R., Krzeminski, W., Soderberg, A. M., Frail, D. A., ...

We present optical and near-infrared searches for afterglow emission from the first four Swift bursts with accurate positions from the X-ray Telescope (XRT). Using telescopes at Las Campanas, Keck,...

SN 2005bf: A Possible Transition Event Between Type Ib/c Supernovae and Gamma Ray Bursts (2005)

Folatelli, Gaston, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...

We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first ~100 days following discovery. The u'g'BV light curves displayed a double-peaked morphology,...

SN 2005bf: A Possible Transition Event Between Type Ib/c Supernovae and Gamma Ray Bursts (2005)

Folatelli, Gaston, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...

We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first ~100 days following discovery. The u'g'BV light curves displayed a double-peaked morphology,...

Hubble Space Telescope First Observations of the Brightest Stars in the Virgo Galaxy M100 = NGC 4321 (2004)

Freedman, W.L., Madore, B.F., Stetson, P.B., Hughes, S.M.G., Holtzman, J.A., Mould, J.R., ...

As part of both the Early Release Observations fromthe Hubble Space Telescope and the Key PRoject on the Extragalctic Distance Scale, we have obtained multi-wavelength BVR WFPC2 images for the...

Distance to the Virgo Cluster Galaxy M100 from Hubble Space Telescope Observations of Cepheids (2004)

Freedman, W.L., Madore, B.F., Mould, J.R., Hill, R., Ferrarese, L., Kennicutt, R. C. Jr., ...

Accurate distances to galaxies are critical to determining the present expansion rate of the Universe or Hubble Constant (H0). An important step in resolving the current uncertainty in H0 is the...

The tip of the Red Giant Branch as a Distance Indicator for Resolved Galaxies: II. Computer Simulations (2004)

Madore, B. F., Freedman, W. L.

Based on both empirical data for nearby galaxies, and on computer simulations, we show that measuring the position of the tip of the first-ascent red-giant branch (TRGB) provides a means of obtaining...

The Hubble Space Telescope Extragalactic Distance Scale Key Project. X. The Cepheid Distance to NGC 7331 (2004)

Hughes, S. M. G., Han, M., Hoessel, J., Saha, A., Silbermann, N., Stetson, P. B., ...

The distance to NGC 7331 has been derived from Cepheid variables observed with HST/WFPC2, as part of the Extragalactic Distance Scale Key Project. Multi-epoch exposures in F555W(~V) and F814W (~1),...

Teh Extragalctic Distance Scale Key Project VII. The Discovery of Cepheids in the Leo I Group Galaxy NGC 3351 Using the Hubble Space Telescope (2004)

Graham, J. A., Phelps, R. L., Freedman, W. L., Saha, A., Ferarese, L., Stetson, P. B., ...

We report on the discovery and properties of Cepheid variable stars in the barred spiral galaxy NGC 3351 which is a member of the LeoI group of galaxies.

The Mean Flux of the Optical Extragalactic Background Light: Preliminary Results from HST and Las Campanas (2004)

Bernstein, R. A., Freedman, W. L.

Hubble Space Telescope Observations of M32: The Color-Magnitude Diagram (2004)

Grillmair, C. J., Lauer, T. R., Worthey, G., Faber, S. M., Freedman, W. L., Madore, B. F., ...

We present a V--I color-magnitude diagram for a region 1'--2' the center of M32 based on Hubble Space Telescope WFPC2 images. The broad color-luminosity distribution of red giants shows that the...

The Extragalactic Distance Scale Key Project VIII. The Discovery of Cepheids and a New Distance to NGC 3621 Using the Hubble Space Telescope (2004)

Rawson, D. M., Mould, J. R., Macri, L. M., Huchra, J. P., Kennicutt, R. C., Harding, P., ...

We report on the discovery of Cepheids in the field spiral galaxy NGC3621, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST). NGC 3621 is...

The HST Key Project on the Extragalactic Distance Scale XX. The Discovery of Cepheids in the Virgo Cluster Galaxy NGC 4548 (2004)

Graham, J. A., Ferrarese, L., Freedman, W. L., Kennicutt, R. C., Mould, J. R., Saha, A., ...

This is one of the galaxies being observed as part of the Hubble Space Telescope (HST) Key Project on the Extragalactic Distance Scale which aims to determine the Hubble Constant to 10% accuracy.

The HST Key Project on the Extragalactic Distance Scale XIV. The Cepheids in NGC 1365 (2004)

Silbermann, N., Harding, P., Ferrarese, L., Stetson, P. B., Madore, B. F., Kennicutt, R. C., ...

We report the detection of Cepheid variable stars in the barred spiral galaxy NGC 1365, located in the Fornax cluster, using the Hubble Space Telescope Wide Field and Planetary Camera 2. Twelve V...

The HST Key Project on the Extragalactic Distance Scale (2004)

Ferrarese, L., Bresolin, F., Kennicutt, R. C. Jr., Saha, A., Stetson, P. B., Freedman, W. L., ...

We report the detection of Cepheids and a new distance to the spiral galaxy NGC 2541, based on data obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST).

The HST Key Project on the Extragalactic Distance Scale. XV. Implications of a Cepheid Distance to the Fornax Cluster (2004)

Madore, B. F., Freedman, W. L., Silbermann, N., Harding, P., Huchra, J., Mould, J. R., ...

Using the Hubble Space Telescope (HST) thirty-seven long-period Cepheid variables have been discoverd in the Fornax Cluster spiral galaxy NGC 1365.

The HST Key Project on the Extragalactic Distance Scale XI. The Cepheids in NGC 4414 (2004)

Turner, A., Ferrarese, L., Saha, A., Bresolin, F., Kennicutt, R. C. Jr., Stetson, P. B., ...

We report the Discovery of Cepheid variable stars in the galaxy NGC 4414, as part of the Hubble Space Telescope (HST) Key Project on the Extragalactic Distance Scale. Observations were obtained with...

A Cepheid Distance to the Fornax Cluster and the Local Expansion Rate of the Universe (2004)

Madore, B. F., Freedman, W. L., Silbermann, N., Harding, P., Huchra, J., Mould, J. R., ...

The determination of an accurate value of the Hubble constant requires the measurement of accurate galaxy distances and velocities. Both the Virgo and Fornax clusters of galaxies are close enough to...

The HST Key Project on the Extragalactic Distance Scale XVII. The Cepheid Distance to the Coma II Group Galaxy NGC 4725 (2004)

Gibson, B. K., Hughes, S. M. G., Stetson, P. B., Ferrarese, L., Ford, H., Freedman, W. L., ...

The distance to NGC 4725 has been derived from Cepheid variables, as part of the Hubble Space Telescope Key Project on the Extragalactic Distance Scale.

The Extragalactic Distance Scale Key Project. XVI. Cepheid Variables in an Inner Field of M101 (2004)

Stetson, P. B., Saha, A., Ferrarese, L., Rawson, D. M., Ford, H. C., Freedman, W. L., ...

We report on the identification of 255 candidate variable stars in a field located some 1.7 from the center of the late-type spiral galaxy M101 = NGC 5457, based on observations made with the Wide...

Cepheid and Tip of the Red Giant Branch Distances to the Dwarf Irregular Galaxy IC 10 (2004)

Sakai, S., Madore, B. F., Freedman, W. L.

We present color-magnitude diagrams and luminosity functions of stars in the nearby galaxy IC 10, based on VI CCD photometry acquired with the COSMIC prime-focus camera on the Palomer 5m telescope.

Companions to isolated elliptical galaxies: revisiting the Bothun-Sullivan (1977) sample using the NASA/IPAC extragalactic database (2004)

Madore, B. F., Freedman, W. L., Bothun, G. D.

We investigate the number of physical companion galaxies for a sample of relatively isolated elliptical galaxies. The NASA/IPAC Extragalactic Database (NED) has been usedto reinvestigate the...

The sub-energetic GRB 031203 as a cosmic analogue to GRB 980425 (2004)

Soderberg, A. M., Kulkarni, S. R., Berger, E., Fox, D. W., Sako, M., Frail, D. A., ...

Over the six years since the discovery of the gamma-ray burst GRB 980425, associated with the nearby (distance, ~40 Mpc) supernova 1998bw, astronomers have fiercely debated the nature of this event....

The J-band Light Curve of SN 2003lw, Associated with GRB 031203 (2004)

Gal-Yam, A., Fox, D. B., Soderberg, A. M., Kulkarni, S. R., Berger, E., ...

At z=0.1055, the gamma-ray burst GRB 031203 is one of the two nearest GRBs known. Using observations from the Very Large Array (VLA) and Chandra X-ray Observatory, we derive sub-arcsecond...

The variable star population in Phoenix: coexistence of Anomalous and short-period Classical Cepheids, and detection of RR Lyrae variables (2004)

Gallart, C., Aparicio, A., Freedman, W. L., Madore, B. F., Martinez-Delgado, D., Stetson, P. B.

We present the results of a search for variable stars in the Local Group dwarf galaxy Phoenix. Nineteen Cepheids, six candidate long-period variables, one candidate eclipsing binary and a large...

The variable-star population in Phoenix: Coexistence of anomalous and short-period classical Cepheids and detection of RR Lyrae variables (2004)

Gallart, C., Aparicio, A., Freedman, W. L., Madore, B. F., Martínez-Delgado, D., Stetson, P. B.

We present the results of a search for variable stars in the Local Group dwarf galaxy Phoenix. Nineteen Cepheids, six candidate long-period variables, one candidate eclipsing binary, and a large...

Infrared Light Curves of Type Ia Supernovae (2002)

Phillips, M. M., Krisciunas, K., Suntzeff, N. B., Roth, M., Germany, L., Candia, P., ...

This paper provides a progress report on a collaborative program at the Las Campanas and Cerro Tololo Observatories to observe the near-IR light curves of Type Ia supernovae. We discuss how the...

The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (III): Cosmological Implications (2001)

Bernstein, R. A., Freedman, W. L., Madore, B. F.

(Abridged) We have used HST WFPC2 and ground-based spectroscopy to measure the integrated extragalactic background light (EBL) at optical wavelengths. We have also computed the integrated light from...

The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (II): Measurement of Foreground Zodiacal Light (2001)

Bernstein, R. A., Freedman, W. L., Madore, B. F.

We present a measurement of the absolute surface brightness of the zodiacal light (3900-5100A) toward a fixed extragalactic target at high ecliptic latitude based on moderate resolution (~1.3A per...

The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (I): Results (2001)

Bernstein, R. A., Freedman, W. L., Madore, B. F.

(Abridged) We present the first detections of the mean flux of the optical extragalactic background light (EBL) at 3000, 5500, and 8000A. Diffuse foreground flux at these wavelengths comes from...

The Discovery of Cepheids and a New Distance to NGC 2841 Using the Hubble Space Telescope (2001)

Macri, L. M., Stetson, P. B., Bothun, G. D., Freedman, W. L., Garnavich, P. M., Jha, S., ...

We report on the discovery of Cepheids in the spiral galaxy NGC 2841, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. NGC 2841 was observed...

The Distance to SN 1999em from the Expanding Photosphere Method (2001)

Hamuy, M., Pinto, P. A., Maza, J., Suntzeff, N. B., Phillips, M. M., Eastman, R. G., ...

We present optical and IR spectroscopy of the first two months of evolution of the Type II SN 1999em. We combine these data with high-quality optical/IR photometry beginning only three days after...

NICMOS Observations of Extragalactic Cepheids. I. Photometry Database and a Test of the Standard Extinction Law (2001)

Macri, L. M., Calzetti, D., Freedman, W. L., Gibson, B. K., Graham, J. A., Huchra, J. P., ...

We present the results of near-infrared observations of extragalactic Cepheids made with the Near Infrared Camera and Multi-Object Spectrometer on board the Hubble Space Telescope. The variables are...

Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant (2000)

Freedman, W. L., Madore, B. F., Gibson, B. K., Ferrarese, L., Kelson, D. D., Sakai, S., ...

We present here the final results of the Hubble Space Telescope Key Project to measure the Hubble constant. We summarize our method, the results and the uncertainties, tabulate our revised distances,...

Comparing Galaxy Morphology at Ultraviolet and Optical Wavelengths (2000)

Kuchinski, L. E., Freedman, W. L., Madore, Barry F., Trewhella, M., Bohlin, R. C., Cornett, R. H., ...

We have undertaken an imaging survey of 34 nearby galaxies in far-ultraviolet (FUV, ~1500A) and optical (UBVRI) passbands to characterize galaxy morphology as a function of wavelength. This sample,...

The Local Group galaxy candidates Cas dSph, Peg dSph=AndVI, and Cam A (1999)

Gallart, C., Martinez-Delgado, D., Aparicio, A., Freedman, W. L.

We present observations of the new Local Group galaxy candidates Cassiopeia dSph, Pegasus dSph=AndVI and Camelopardalis A. Our deep color-magnitude diagrams show that the first two galaxies are...

The Extragalactic Distance Scale Key Project XVIII. The Discovery of Cepheids and a New Distance to NGC 4535 Using the Hubble Space Telescope (1999)

Macri, L. M., Huchra, J. P., Stetson, P. B., Silbermann, N. A., Freedman, W. L., Kennicutt, R. C., ...

We report on the discovery of Cepheids in the Virgo spiral galaxy NGC 4535, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. NGC 4535 is one...

HST observations of the Local Group dwarf galaxy Leo I (1998)

Gallart, C., Freedman, W. L., Mateo, M., Chiosi, C., Thompson, I. B., Aparicio, A., ...

We present deep HST F555W (V) and F814W (I) observations of a central field in the Local Group dwarf spheroidal (dSph) galaxy Leo I. The resulting color-magnitude diagram (CMD) reaches I \simeq 26...

A Cepheid Distance to the Fornax Cluster (1998)

Madore, B. F., Freedman, W. L., Silbermann, N., Harding, P., Huchra, J., Mould, J. R., ...

The Hubble Space Telescope is being used to measure accurate Cepheid distances to nearby galaxies with the ultimate aim of determining the Hubble constant, H_0. For the first time, it has become...

The HST Key Project on the Extragalactic Distance Scale XIV. The Cepheids in NGC 1365 (1998)

Silbermann, N. A., Harding, P., Ferrarese, L., Stetson, P. B., Madore, B. F., Kennicutt, R. C., ...

We report the detection of Cepheid variable stars in the barred spiral galaxy NGC 1365, located in the Fornax cluster, using the Hubble Space Telescope Wide Field and Planetary Camera 2. Twelve V...

The Extragalactic Distance Scale Key Project I. The Discovery Of And A New Distance To M81 Using The (1997)

W. L. Freedman, S. M. Hughes, B. F. Madore, J. R. Mould, M. G. Lee, P. B. Stetson, ...

We report on the discovery of 30 new Cepheids in the nearby galaxy M81 based on observations using the Space Telescope The periods for these lie in the range of 10 to 55 days, based on 18 independent...

W. L. Freedman

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