Variable Sodium Absorption in a Low-extinction Type Ia Supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the...
Variable Sodium Absorption in a Low-Extinction Type Ia Supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the...
Exploring the Optical Transient Sky with the Palomar Transient Factory (2009)
Rau, Arne, Kulkarni, Shrinivas R., Law, Nicholas M., Bloom, Joshua S., Ciardi, David, Djorgovski, George S., ...
The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes to years. PTF uses the CFH12k mosaic camera,...
Type II Supernovae as Probes of Cosmology (2009)
Poznanski, Dovi, Baron, Eddie, Blondin, Stephane, Bloom, Joshua S., D'Andrea, Christopher B., Della Valle, Massimo, ...
- Constraining the cosmological parameters and understanding Dark Energy have tremendous implications for the nature of the Universe and its physical laws. - The pervasive limit of systematic...
The Chemical Abundances of Tycho G in Supernova Remnant 1572 (2009)
González Hernández, Jonay I., Ruiz-Lapuente, Pilar, Filippenko, Alexei V., Foley, Ryan J., Gal-Yam, Avishay, Simon, Joshua D.
We present an analysis of the chemical abundances of the star Tycho G in the direction of the remnant of supernova (SN) 1572, based on Keck high-resolution optical spectra. The stellar parameters of...
The chemical abundances of tycho G in supernova remnant 1572 (2009)
González Hernández, Jonay I., Ruiz-Lapuente, Pilar, Filippenko, Alexei V., Foley, Ryan J., Gal-Yam, Avishay, Simon, Joshua D.
Variable sodium absorption in a low-extinction type Ia supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Leonard, Douglas C., Gal-Yam, Avishay, Fox, Derek B., Cameron, P. B., Johansson, Erik M., Kraus, Adam L., ...
We analyze two pre-supernova (SN) and three post-SN high-resolution images of the site of the Type II-Plateau supernova SN 2006my in an effort to either detect the progenitor star or to constrain its...
New imaging and spectroscopy of the locations of several short-hard gamma-ray bursts (2008)
Gal-Yam, Avishay, Nakar, Ehud, Ofek, Eran O., Cenko, S. B., Kulkarni, S. R., Soderberg, A. M., ...
The detection and characterization of the afterglow emission and host galaxies of short-hard gamma-ray bursts (SHBs) is one of the most exciting recent astronomical discoveries. In particular,...
Proper motions with Subaru I. Methods and a first sample in the Subaru Deep Field (2008)
Richmond, Michael W., Morokuma, Tomoki, Doi, Mamoru, Komiyama, Yutaka, Yasuda, Naoki, Okamura, Sadanori, ...
We search for stars with proper motions in a set of twenty deep Subaru images, covering about 0.28 square degrees to a depth of i ~ 25, taken over a span of six years. In this paper, we describe in...
Leonard, Douglas C., Gal-Yam, Avishay, Fox, Derek B., Cameron, P. B., Johansson, Erik M., Kraus, Adam L., ...
We analyze two pre-supernova (SN) and three post-SN high-resolution images of the site of the Type II-Plateau supernova SN 2006my in an effort to either detect the progenitor star or to constrain its...
The Chemical Abundances of Tycho G in Supernova Remnant 1572 (2008)
Hernández, Jonay I. González, Ruiz-Lapuente, Pilar, Filippenko, Alexei V., Foley, Ryan J., Gal-Yam, Avishay, Simon, Joshua D.
We present an analysis of the chemical abundances of the star Tycho G in the direction of the remnant of supernova (SN) 1572, based on Keck high-resolution optical spectra. The stellar parameters of...
A comprehensive study of GRB 070125, a most energetic gamma-ray burst (2008)
Chandra, Poonam, Cenko, S. Bradley, Frail, Dale A., Chevalier, Roger A., Macquart, Jean-Pierre, Kulkarni, Shri R., ...
We present a comprehensive multiwavelength analysis of the bright, long-duration gamma-ray burst GRB 070125, comprised of observations in gamma-ray, X-ray, optical, millimeter, and centimeter wave...
A comprehensive study of GRB 070125, a most energetic gamma-ray burst (2008)
Chandra, Poonam, Cenko, S. Bradley, Frail, Dale A., Chevalier, Roger A., Macquart, Jean-Pierre, Kulkarni, Shri R., ...
We present a comprehensive multiwavelength analysis of the bright, long-duration gamma-ray burst GRB 070125, comprised of observations in gamma-ray, X-ray, optical, millimeter, and centimeter wave...
GRB 070125: The first long-duration gamma-ray burst in a halo environment (2008)
Cenko, S. Bradley, Fox, Derek B., Penprase, Brian E., Cucchiara, Antonio, Price, Paul A., Berger, Edo, ...
We present the discovery and high signal-to-noise ratio spectroscopic observations of the optical afterglow of the long-duration gamma-ray burst GRB 070125. Unlike all previously observed...
A comprehensive study of GRB 070125, a most energetic gamma ray burst (2008)
Chandra, Poonam, Cenko, S. Bradley, Frail, Dale, Chevalier, Roger, Macquart, Jean-Pierre, Kulkarni, Shri, ...
We present a comprehensive multiwavelength analysis of the bright, long duration gamma-ray burst GRB 070125, comprised of observations in $\gamma$-ray, X-ray, optical, millimeter and centimeter...
Cenko, S. Bradley, Berger, Edo, Nakar, Ehud, Kasliwal, Mansi M., Cucchiara, Antonio, Kulkarni, Shri R., ...
We present optical spectra of the host galaxies of the short-duration gamma-ray burst GRB 070429B and the likely short-duration with extended emission GRB 070714B. In both cases, we find a single...
Seeking for the progenitors of type Ia supernovae (2008)
Patat, Ferdinando, Chandra, Poonam, Chevalier, Roger, Justham, Stephen, Podsiadlowski, Philipp, Wolf, Christian, ...
Models for the Type Ic Hypernova SN 2003lw associated with GRB 031203 (2007)
Mazzali, Paolo A., Deng, Jinsong, Pian, Elena, Malesani, Daniele, Tominaga, Nozomu, Maeda, Keiichi, ...
The Gamma-Ray Burst 031203 at a redshift z=0.1055 revealed a highly reddened Type Ic Supernova, SN 2003lw, in its afterglow light. This is the third well established case of a link between a...
Gal-Yam, Avishay, Maoz, Dan, Guhathakurta, Puragra, Filippenko, Alexei V.
We describe the Wise Observatory Optical Transient Search (WOOTS), a survey for supernovae (SNe) and other variable and transient objects in the fields of redshift 0.06-0.2 Abell galaxy clusters. We...
Constraints on Circumstellar Material Around the Type Ia Supernova 2007af (2007)
Simon, Joshua D., Gal-Yam, Avishay, Penprase, Bryan E., Li, Weidong, Quimby, Robert M., Silverman, Jeffrey M., ...
Patat et al. recently inferred the existence of circumstellar material around a normal Type Ia supernova (SN) for the first time, finding time-variable Na I D absorption lines in the spectrum of SN...
Bayesian single-epoch photometric classification of supernovae (2007)
Poznanski, Dovi, Maoz, Dan, Gal-Yam, Avishay
Ongoing supernova (SN) surveys find hundreds of candidates that require confirmation for their various uses. Traditional classification based on follow- up spectroscopy of all candidates is virtually...
Supernovae in the Subaru Deep Field: An Initial Sample, and Type Ia Rate, out to Redshift 1.6 (2007)
Poznanski, Dovi, Maoz, Dan, Yasuda, Naoki, Foley, Ryan J., Doi, Mamoru, Filippenko, Alexei V., ...
Large samples of high-redshift supernovae (SNe) are potentially powerful probes of cosmic star formation, metal enrichment, and SN physics. We present initial results from a new deep SN survey, based...
On the progenitor of SN 2005gl and the nature of Type IIn supernovae (2007)
Gal-Yam, Avishay, Leonard, D. C., Fox, D. B., Cenko, S. B., Soderberg, A. M., ...
We present a study of the type IIn supernova (SN) 2005gl, in the relatively nearby (d~66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate it is a typical member of its class....
On the Progenitor of SN 2005gl and the Nature of Type IIn Supernovae (2007)
Gal-Yam, Avishay, Leonard, D. C., Fox, D. B., Cenko, S. B., Soderberg, A. M., ...
We present a study of the Type IIn supernova (SN) 2005gl, in the relatively nearby (d ≈ 66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate that it is a typical member of its...
A High-Resolution Spectrum of the Extremely Metal-rich Bulge G Dwarf OGLE-2006-BLG-265 (2007)
Johnson, Jennifer A., Gal-Yam, Avishay, Leonard, Douglas C., Simon, Joshua D., Udalski, Andrzej, Gould, Andrew
We present an R = 45,000 Keck spectrum of the microlensed Galactic bulge G dwarf OGLE-2006-BLG-265, which has high (~60) signal-to-noise ratio despite its short (15 minute) exposure time, because the...
Preliminary Results from the Caltech Core-Collapse Project (CCCP) (2006)
Gal-Yam, Avishay, Cenko, S. B., Fox, D. B., Leonard, D. C., Sand, D. J., ...
We present preliminary results from the Caltech Core-Collapse Project (CCCP), a large observational program focused on the study of core-collapse SNe. Uniform, high-quality NIR and optical photometry...
Supernovae in Low-Redshift Galaxy Clusters: the Type-Ia Supernova Rate (2006)
Sharon, Keren, Gal-Yam, Avishay, Maoz, Dan, Filippenko, Alexei V., GuhaThakurta, Puragra
Supernova (SN) rates are a potentially powerful diagnostic of star formation history (SFH), metal enrichment, and SN physics, particularly in galaxy clusters with their deep, metal-retaining...
Bayesian Single-Epoch Photometric Classification of Supernovae (2006)
Poznanski, Dovi, Maoz, Dan, Gal-Yam, Avishay
(abridged) Ongoing supernova (SN) surveys find hundreds of candidates, that require confirmation for their use. Traditional classification based on followup spectroscopy of all candidates is...
Observational Limits on X-ray Bursts from RRAT J1911+00 (2006)
Hoffman, Kelsey, Rutledge, Robert E., Fox, Derek B., Gal-Yam, Avishay, Cenko, S. Bradley
(abridged) The high radio-flux brightness temperature of the recently discovered class of sources known as Rotating RAdio Transients (RRATs) motivates detailed study in the X-ray band. We describe...
A High-Resolution Spectrum of the Extremely Metal-Rich Bulge G-Dwarf OGLE-2006-BLG-265 (2006)
Johnson, Jennifer A., Gal-Yam, Avishay, Leonard, Douglas C., Simon, Joshua D., Udalski, Andrzej, Gould, Andrew
We present an R=45,000 Keck spectrum of the microlensed Galactic bulge G-dwarf OGLE-2006-BLG-265, which has a high (~60) signal-to-noise ratio despite its short (15 min) exposure time because the...
The Automated Palomar 60-Inch Telescope (2006)
Cenko, S. Bradley, Fox, Derek B., Moon, Dae-Sik, Harrison, Fiona A., Kulkarni, S. R., Henning, John R., ...
We have converted the Palomar 60-inch telescope (P60) from a classical night assistant-operated telescope to a fully robotic facility. The automated system, which has been operational since September...
On the progenitor of SN 2005gl and the nature of Type IIn supernovae (2006)
Gal-Yam, Avishay, Leonard, D. C., Fox, D. B., Cenko, S. B., Soderberg, A. M., ...
We present a study of the type IIn supernova (SN) 2005gl, in the relatively nearby (d~66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate it is a typical member of its class....
Toward a cosmological Hubble diagram for Type II-P supernovae (2006)
Nugent, Peter, Sullivan, Mark, Ellis, Richard, Gal-Yam, Avishay, Leonard, Douglas C., Howell, D. Andrew, ...
We present the first high-redshift Hubble diagram for Type II-P supernovae (SNe II-P) based on five events at redshift up to z ~ 0.3. This diagram was constructed using photometry from the...
Towards a Cosmological Hubble Diagram for Type II-P Supernovae (2006)
Nugent, Peter, Sullivan, Mark, Ellis, Richard, Gal-Yam, Avishay, Leonard, Douglas C., Howell, D. Andrew, ...
We present the first high-redshift Hubble diagram for Type II-P supernovae (SNe II-P) based upon five events at redshift up toz~;0.3. This diagram was constructed using photometry from the...
Models for the Type Ic Hypernova SN 2003lw associated with GRB 031203 (2006)
Mazzali, Paolo A., Deng, Jinsong, Pian, Elena, Malesani, Daniele, Tominaga, Nozomu, Maeda, Keiichi, ...
The Gamma-Ray Burst 031203 at a redshift z=0.1055 revealed a highly reddened Type Ic Supernova, SN 2003lw, in its afterglow light. This is the third well established case of a link between a...
Towards a Cosmological Hubble Diagram for Type II-P Supernovae (2006)
Nugent, Peter, Sullivan, Mark, Ellis, Richard, Gal-Yam, Avishay, Leonard, Douglas C., Howell, D. Andrew, ...
We present the first high-redshift Hubble diagram for Type II-P supernovae (SNe II-P) based upon five events at redshift up to z~0.3. This diagram was constructed using photometry from the...
A non-spherical core in the explosion of supernova SN 2004dj (2006)
Leonard, Douglas C., Filippenko, Alexei V., Ganeshalingam, Mohan, Serduke, Franklin J. D., Li, Weidong, Swift, Brandon J., ...
An important and perhaps critical clue to the mechanism driving the explosion of massive stars as supernovae is provided by the accumulating evidence for asymmetry in the explosion. Indirect evidence...
On the progenitor of SN 2005gl and the nature of Type IIn supernovae (2006)
Gal-Yam, Avishay, Leonard, D. C., Fox, D. B., Cenko, S. B., Soderberg, A. M., ...
We present a study of the type IIn supernova (SN) 2005gl, in the relatively nearby (d~66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate it is a typical member of its class....
Models for the type Ic hypernova SN 2003lw associated with GRB 031203 (2006)
Mazzali, Paolo A., Deng, Jingsong, Pian, Elena, Malesani, Daniele, Tominaga, Nozomu, Maeda, Keiichi, ...
Nakar, Ehud, Gal-Yam, Avishay, Fox, Derek B.
The recent discovery of the first four afterglows of short-hard gamma-ray bursts (SHBs), suggests that they typically result from long-lived progenitor systems. The most popular progenitor model...
The Progenitors of Short-Hard Gamma-Ray Bursts from an Extended Sample of Events (2005)
Gal-Yam, Avishay, Nakar, Ehud, Ofek, Eran, Fox, D. B., Cenko, S. B., Kulkarni, S. R., ...
The detection of the afterglow emission and host galaxies of short-hard gamma-ray bursts (SHBs) is one of the most exciting recent astronomical discoveries. Indications that SHB progenitors belong to...
Gal-Yam, Avishay, Ofek, Eran O., Poznanski, Dovi, Levinson, Amir, Waxman, Eli, Frail, Dale A., ...
We had previously reported on a survey for radio transients, used to set an upper limit on the number of orphan gamma-ray burst (GRB) radio afterglows, and thus a lower limit on the typical GRB...
The distances of short-hard GRBs and the SGR connection (2005)
Nakar, Ehud, Gal-Yam, Avishay, Piran, Tsvi, Fox, Derek B.
We present a search for nearby (D
An asymmetric energetic type Ic supernova viewed off-axis, and a link to gamma ray bursts (2005)
Mazzali, Paolo A., Kawabata, Koji S., Maeda, Keiichi, Nomoto, Ken'ichi, Filippenko, Alexei V., Ramirez-Ruiz, Enrico, ...
Rajala, Anne M., Fox, Derek B., Gal-Yam, Avishay, Leonard, Douglas C., Soderberg, Alicia M., Kulkarni, S. R., ...
We present photometric typing analyses of three young supernovae observed with the Robotic 60-inch Telescope at Palomar Observatory (P60). This represents the first time that such photo-typing has...
Photometric Identification of Young Stripped-Core Supernovae (2004)
Gal-Yam, Avishay, Poznanski, Dovi, Maoz, Dan, Filippenko, Alexei V., Foley, Ryan J.
We present a method designed to identify the spectral type of young (less than ~30 days after explosion) and nearby (z < ~0.05) supernovae (SNe) using their broad-band colors. In particular, we show...
Constraints on SN Ia Progenitors and ICM enrichment from field and cluster SN rates (2003)
The iron mass in galaxy clusters is about 6 times larger than could have been produced by core-collapse SNe, assuming the stars in cluster galaxies formed with a standard IMF. Type-Ia SNe have been...
We use the redshift distribution of type-Ia supernovae (SNe) discovered by the Supernova Cosmology Project to constrain the star formation history (SFH) of the Universe and SN Ia progenitor models....
The iron mass in galaxy clusters is about 6 times larger than could have been produced by core-collapse supernovae (SNe), assuming the stars in the cluster formed with a standard initial mass...
Using Multi-Band Photometry to Classify Supernovae (2003)
Poznanski, Dovi, Gal-Yam, Avishay, Maoz, Dan, Filippenko, Alexei V., Leonard, Douglas C., Matheson, Thomas
Large numbers of supernovae (SNe) have been discovered in recent years, and many more will be found in the near future. Once discovered, further study of a SN and its possible use as an astronomical...
A Population of Intergalactic Supernovae in Galaxy Clusters (2002)
Gal-Yam, Avishay, Maoz, Dan, Guhathakurta, Puragra, Filippenko, Alexei V.
We have discovered seven type Ia cluster supernovae (SNe) in the course of the Wise Observatory Optical Transients Search in the fields of galaxy clusters with redshifts between z=0.06 and z=0.2. Two...
Supernova 2002ap - The First Month (2002)
Gal-Yam, Avishay, Ofek, Eran O., Shemmer, Ohad
Supernova (SN) 2002ap in M74 was discovered on January 29, 2002. Being one of the nearest (10 Mpc) SN events in the last decades, and spectroscopically similar to the so-called ``hypernovae'' 1997ef...
Orphan GRB radio afterglows: Candidates and constraints on beaming (2002)
Levinson, Amir, Ofek, Eran, Waxman, Eli, Gal-Yam, Avishay
The number of orphan radio afterglows associated with gamma-ray bursts (GRBs) that should be detected by a flux limited radio survey, is calculated. It is shown that for jetted GRBs this number is...
SDSS J124602.54+011318.8: A Highly Variable AGN, Not an Orphan GRB Afterglow (2002)
Gal-Yam, Avishay, Ofek, Eran O., Filippenko, Alexei V., Chornock, Ryan, Li, Weidong
The optically variable source SDSS J124602.54+011318.8 first appears in Sloan Digital Sky Survey (SDSS) data as a bright point source with nonstellar colors. Subsequent SDSS imaging and spectroscopy...
Not Color Blind: Using Multiband Photometry to Classify Supernovae (2002)
Poznanski, Dovi, Gal-Yam, Avishay, Maoz, Dan, Filippenko, Alexei V., Leonard, Douglas C., Matheson, Thomas
Large numbers of supernovae (SNe) have been discovered in recent years, and many more will be found in the near future. Once discovered, further study of a SN and its possible use as an astronomical...
Gal-Yam, Avishay, Maoz, Dan, Sharon, Keren
We have searched for high-redshift supernova (SN) candidates in multiple deep Hubble Space Telescope (HST) archival images of nine galaxy-cluster fields. We detect six apparent SNe, with I814 between...
The Unique Type Ia Supernova 2000cx in NGC 524 (2001)
Li, Weidong, Filippenko, Alexei V., Gates, Elinor, Chornock, Ryan, Gal-Yam, Avishay, Ofek, Eran O., ...
We present extensive photometric and spectroscopic observations of the Type Ia supernova (SN Ia) 2000cx in the S0 galaxy NGC 524, which reveal it to be peculiar. Photometrically, SN 2000cx is...
Supernova rates in Abell galaxy clusters and implications for metallicity (1999)
Supernovae (SNe) play a critical role in the metal enrichment of the intra-cluster medium (ICM) in galaxy clusters. Not only are SNe the main source for metals, but they may also supply the energy to...
Supernova rates in Abell galaxy clusters and implications for metallicity (1999)
Supernovae (SNe) play a critical role in the metal enrichment of the intra-cluster medium (ICM) in galaxy clusters. Not only are SNe the main source for metals, but they may also supply the energy to...
A survey for large image-separation lensed quasars (1996)
Maoz, Dan, Rix, Hans-Walter, Gal-Yam, Avishay, Gould, Andrew
The statistics of gravitationally lensed quasars with multiple images in the 0.1''-7'' range have been measured in various surveys. Little is known, however, about lensed-quasar statistics at larger...