DSpace Angular :: Browsing by Author "Drake, A. J."

Browsing by Author "Drake, A. J."

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A Supernova Candidate from the Siding Spring Survey
(2010) Drake, A. J.; Djorgovski, S. G.; Mahabal, A. A.; Graham, M. J.; Williams, R.; Prieto, J.; Catelan , Marcio; Christensen, E.; McNaught, R.; Garradd, G.; Beshore, E. C.; Larson, S. M.
We report the discovery of the first supernova candidate from the Siding Spring Survey (SSS) by the Catalina Real-time Transient Survey (CRTS). The detection has the following details: <table border=1 width=650 align=center> <tr><th>ID</th><th>Disc. Date</th><th>RA</th><th>Dec</th><th>Disc. Mag</th></tr> <tr align=center><td><a href='http://crts.caltech.edu/ATEL/SSS/1005080151534122262.atel.html'> SSS100508:210144-143830</a></td><td> 2010-05-08 </td><td> 21:01:44.10 </td><td> -14:38:30.5 </td><td> 16.4</tr> </table> The host galaxy, 2MFGC 15924 (=PGC 187888), has redshift z=0.0275 (Jones et al....
Discovery and Classification of Transients from CRTS-II
(2016) Drake, A. J.; Djorgovski, S. G.; Mahabal, A. A.; Graham, M. J.; Stern, D.; Catelan, Márcio; Christensen, E.; Larson, S. M.
Following on from the Catalina Real-time Transient Survey (CRTS), the CRTS-II project has begun to search for transients and highly variable sources. As with CRTS, all detections will be made public immediately following discovery....
Discovery of ~9000 new RR Lyrae in the southern Catalina surveys
(2015) Torrealba, G.; Catelan, Márcio; Drake, A. J.; Djorgovski, S. G.; McNaught, R. H.; Belokurov, V.; Koposov, S.M.; Graham, M. J.; Mahabal, A.; Larson, S.; Christensen, E.
Interacting supernovae and supernova impostors. LSQ13zm : an outburst heralds the death of a massive star
(2016) Tartaglia, L.; Pastorello, A.; Sullivan, M.; Baltay, C.; Rabinowitz, D.; Nugent, P.; Drake, A. J.; Djorgovski, S. G.; Gal-Yam, A.; Bauer, Franz Erik; Barsukova, E. A.; Goranskij, V. P.; Valeev, A. F.; Fatkhullin, T.; Schulze, S.; Mehner, A.; Fabrika, S.; Taubenberger, S.; Nordin, J.; Valenti, S.
Near-Field Cosmology with RR Lyrae Variable Stars: a first view of substructure in the southern sky
(2016) Navarrete, C.; Duffau, S.; Vivas, A. K.; Catelan, Márcio; Hajdu, G.; Torrealba, G.; Cortés, C.; Belokurov, V.; Koposov, S.; Drake, A. J.
We present the current status of the spectroscopic follow-up of a large number of RR Lyrae (RRL) halo overdensity candidates recently found by Torrealba et al. (2015) using southern-hemisphere data from the Catalina Real-time Transient Survey (CRTS). Characterizing the individual RRL stars in these overdensities is crucial to confirm them as real halo substructures. Low-resolution spectra have been obtained for RRL stars in 11 different overdensities, using the SOAR and Magellan telescopes. Radial velocities and metallicities have been derived so far for 123 and 99 RRL stars, respectively....
Recovering Algol-type eclipsing binaries in the CRTS
(2020) Carmo, A.; Ferreira Lopes, C. E.; Papageorgiou, A.; Jablonski, F. J.; Rodrigues, C. V.; Drake, A. J.; Cross, N. J. G.; Catelan , Marcio
Eclipsing binary systems are relevant to astronomy since they provide primary means of determining fundamental stellar astrophysical quantities such as mass, radius, and temperature of the components. Algol-type eclipsing binaries (EAs) have spherical or slightly ellipsoidal components and are generally systems that produce light curves with narrow eclipses and few points within the eclipse. The most current photometric surveys usually have observation cadences larger than these eclipses duration, which hinders the detection of EAs. The variability of these objects can even be detected, but the period is rarely found because an optimized constraint is required. Thereby, we used a new methodology to find new EAs in the Catalina Real-Time Transient Survey. As a result, we determined periodicity for 56\% of EA$_\mathrm{up}$ (EAs marked as having unknown period), which corresponds to 87 new EAs reported. Also, we use color criteria to select a subsample that contains 8 low-mass binary systems with spectral types K and M. To obtain the individual physical parameters of these components, each light curve was modeled with the Wilson & Devinney light curve synthesis code combined with a Monte Carlo Markov chain process. The results were examined in the scenario of radius inflation of low-mass stars in binary systems....
Recovering variable stars in large surveys: EAup Algol-type class in the Catalina Survey
(OUP, 2020) Carmo, A.; Ferreira Lopes, C. E.; Papageorgiou, A.; Jablonski, F. J.; Rodrigues, C. V.; Drake, A. J.; Cros, N. J. G.; Catelan, Márcio
The discovery and characterization of Algol eclipsing binaries (EAs) provide an opportunity to contribute for a better picture of the structure and evolution of low-mass stars. However, the cadence of most current photometric surveys hinders the detection of EAs since the separation between observations is usually larger than the eclipse(s) duration and hence few measurements are found at the eclipses. Even when those objects are detected as variable, their periods can be missed if an appropriate oversampling factor is not used in the search tools. In this paper, we apply this approach to find the periods of stars catalogued in the Catalina Real-Time Transient Survey (CRTS) as EAs having unknown period (EA up ). As a result, the periods of ∼56percent of them were determined. Eight objects were identified as low-mass binary systems and modelled with the Wilson & Devinney synthesis code combined with a Markov chain Monte Carlo optimization procedure. The computed masses and radii are in agreement with theoretical models and show no evidence of inflated radii. This paper is the first of a series aiming to identify suspected binary systems in large surveys.
SN 2008jb: A "Lost" Core-collapse Supernova in a Star-forming Dwarf Galaxy at ~10 Mpc
(2012) Prieto, J. L.; Lee, J. C.; Drake, A. J.; McNaught, R.; Garradd, G.; Beacom, J. F.; Beshore, E.; Catelan, Marcio; Djorgovski, S. G.; Pojmanski, G.; Stanek, K. Z.; Szczygieł, D. M.
We present the discovery and follow-up observations of SN 2008jb, a core-collapse supernova in the southern dwarf irregular galaxy ESO 302-14 (MB = -15.3 mag) at 9.6 Mpc. This nearby transient was missed by galaxy-targeted surveys and was only found in archival optical images obtained by the Catalina Real-time Transient Survey and the All-Sky Automated Survey. The well-sampled archival photometry shows that SN 2008jb was detected shortly after explosion and reached a bright optical maximum, V max ~= 13.6 mag (M V, max ~= -16.5). The shape of the light curve shows a plateau of ~100 days, followed by a drop of ~1.4 mag in the V band to a slow decline with an approximate 56Co decay slope. The late-time light curve is consistent with 0.04 ± 0.01 M ⊙ of 56Ni synthesized in the explosion. A spectrum of the supernova obtained two years after explosion shows a broad, boxy Hα emission line, which is unusual for normal Type II-Plateau supernovae at late times. We detect the supernova in archival Spitzer and WISE images obtained 8-14 months after explosion, which show clear signs of warm (600-700 K) dust emission. The dwarf irregular host galaxy, ESO 302-14, has a low gas-phase oxygen abundance, 12 + log(O/H) = 8.2 (~1/5 Z ⊙), similar to those of the Small Magellanic Cloud and the hosts of long gamma-ray bursts and luminous core-collapse supernovae. This metallicity is one of the lowest among local (lsim 10 Mpc) supernova hosts. We study the host environment using GALEX far-UV, R-band, and Hα images and find that the supernova occurred in a large star formation complex. The morphology of the Hα emission appears as a large shell (R ~= 350 pc) surrounding the FUV and optical emission. Using the Hα-to-FUV ratio and FUV and R-band luminosities, we estimate an age of ~9 Myr and a total mass of ~2 × 105 M ⊙ for the star formation complex, assuming a single-age starburst. These properties are consistent with the expanding Hα supershells observed in many well-studied nearby dwarf galaxies, which are tell-tale signs of feedback from the cumulative effect of massive star winds and supernovae. The age estimated for the star-forming region where SN 2008jb exploded suggests a relatively high-mass progenitor star with an initial mass M ~ 20 M ⊙ and warrants further study. We discuss the implications of these findings in the study of core-collapse supernova progenitors. This paper includes data gathered with the 6.5 m Magellan telescope at Las Campanas Observatory, Chile....
Supernova 2010gu
(2010) McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.McNaught, R. H.; Garradd, G.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Further to CBET 2387, R. H. McNaught and G. Garradd, Australian National University; A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J. Graham, and R. Williams, California Institute of Technology; J. L. Prieto, Carnegie Observatories; M. Catelan, Pontificia Universidad Catolica de Chile; E. C. Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of Arizona; and E. Christensen, Gemini Observatory, report the CRTS discovery of an apparent supernova in unfiltered Siding Spring Survey (SSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010gu Aug. 7.67 22 19 23.16 -36 58 24.5 18.0 7".0 E, 3".3 N Further SSS magnitudes for 2010gu: July 9.81, [19.5; Aug. 10.76, 17.9. The host galaxy, 2MASX J22192259-3658278, has redshift z = 0.056....
Supernova 2010hj in Pgc 67413
(2010) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; McNaught, R. H.; Garradd, G.; Howerton, S.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the discovery of an apparent supernova in unfiltered Siding Spring Survey (SSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010hj Aug. 4.61 21 49 09.84 -59 02 23.2 17.1 5".5 W, 8".2 S Nothing was visible at this position on an SSS image from 2009 Oct. 1.50 UT (limitiing mag 18.9), but 2010hj was detected again in SSS images on Aug. 29.59 (no magnitude provided). The host galaxy appears to be PGC 67413 = ESO 145-G16. Joseph Brimacombe, Cairns, Australia, reports that ten stacked 600-s CCD images (limiting magnitude 20) taken remotely with a 32-cm RCOS telescope (+ STL6K camera + clear filter) at the Macedon Ranges Observatory near Melbourne, Australia, on Aug. 29.727 show the new object to be at mag 18.3 and located approximately 7" west and 7" south of the presumed host-galaxy nucleus. Another stacked image (seven 1200-s frames; limiting magnitude 20), taken by Brimacombe on Sept. 2.636 with a 40-cm RCOS telescope (+ U16 camera + red filter) at the Coral Towers Observatory (Cairns), yields mag 18.6 for 2010hj; the Sept. 2 stacked image has been posted at the following website URL: http://www.flickr.com/photos/43846774@N02/4952444311/....
Supernova 2010iw near UGC 4570
(2010) Howerton, C.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the discovery by Howerton of an apparent supernova in public Catalina Sky Survey (CSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010iw Oct. 14.66 8 45 15.01 +27 49 21.8 16.4 12".9 W, 3".4 S Further magnitudes for 2010iw: June 11.16 UT, [19.0 (CSS); Oct. 17.50, 16.3 (Howerton, remotely with a 0.6-m LB-1 telescope, Rodeo, NM, U.S.A.). They note that the new object lies 5".4 east and 1".1 north from a galaxy seen in Sloan Digital Sky Survey images with measured redshift z = 0.109; the current luminosity of 2010iw appears too high for it to be a regular supernova associated with this distant galaxy. The host galaxy is thus is likely to be UGC 4570 (at redshift z = 0.0215)....
Supernova 2010jt
(2010) Howerton, S.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; McNaught, R. H.; Garradd, G.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the discovery of an apparent supernova in Siding Spring Survey (SSS) images made public via the "Catalina Real-time Transient Survey" program: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010jt Nov. 6.57 23 43 41.24 -41 18 46.9 19.0 20".5 E, 29".6 N Further SSS magnitudes for 2010jt: Oct. 18.51 UT, [20.5 (co-added image); Nov. 7.50, 19.0. The likely host galaxy, 6dFGS gJ234339.4-411917, has redshift z = 0.053....
Supernova 2010kq in UGC 1769
(2010) Howerton, S.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the CRTS discovery of an apparent supernova in public images from the Catalina Sky Survey (CSS). SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010kq Dec. 7.23 2 18 10.92 +37 05 42.4 18.3 0".3 E, 4".9 S After posting on the CBAT's unconfirmed-objects webpage, Markku Nissinen and Veli-Pekka Hentunen (Varkaus, Finland) report that their exposures (limiting mag R = 18.9; 3-sigma) taken on Dec. 9 remotely with a 51-cm f/6.8 GRAS011 Global-Rent-a-Scope (+ FLI ProLine PL-11002M camera) near Mayhill, NM, USA, yield position end figures 11s.05, 39".9 for 2010kq (which is 1".5 east and 6".1 south of the center of the galaxy UGC 1769); they note that nothing is visible at this position on a red Palomar Sky Survey F plate. Further CCD magnitude estimates for 2010kq (unfiltered unless otherwise noted): Nov. 15.20 UT, [19.5 (CSS); Dec. 9.088, R = 16.4 +/- 0.1 (Nissinen and Hentunen); 9.14, 16.4 (Howerton; remotely using the LB-1 0.6m telescope at Rodeo, NM, U.S.A.). Drake notes that the presumed host galaxy, UGC 1769, has redshift z = 0.027....
Supernova 2010ks in UGC 5622
(2010) Howerton, S.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the CRTS discovery of an apparent supernova in public images from Catalina Sky Survey (CSS). SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010ks Dec. 11.46 10 23 42.44 +33 46 49.0 17.0 7".8 E, 22".0 N Further unfiltered CCD magnitude estimates of 2010ks: June 15.20 UT, [19.3 (CSS); Dec. 12.42, 17.4 (LB-1 0.6-m telescope at Rodeo, NM). The presumed host galaxy, UGC 5622, has redshift z = 0.033....
Supernova 2010ll
(2010) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the CRTS discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010ll Dec. 10.32 4 50 29.81 -10 44 17.0 18.1 11".8 W, 6".3 N Further CSS magnitudes for 2010ll: Nov. 16.39 UT, [20.4; Nov. 30.35, 19.0....
Supernova 2010lr
(2011) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; McNaught, R. H.; Garradd, G.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the CRTS discovery of an apparent supernova in unfiltered Siding Spring Survey (SSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010lr Dec. 30.46 0 02 35.50 -30 43 52.4 18.0 19".4 E, 13".3 N Further SSS magnitudes for 2010lr: 2010 Nov. 4.58 UT, [20.1; Dec. 28.47, 17.9. The presumed host galaxy, 2MASX J00023401-3044061, has redshift z = 0.062....
Supernova 2010lu
(2011) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.
Report the CRTS discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images: SN 2010 UT R.A. (2000.0) Decl. Mag. Offset 2010lu Dec. 8.40 9 06 00.70 +29 20 32.5 16.8 5".8 E, 8".3 S Further CSS magnitudes for 2010lu: 2010 Nov. 7.51 UT, [19.5; 2011 Jan. 3.34, 17.1. The presumed host galaxy, SDSS J090600.26+292041.0, has redshift z = 0.023....
Supernova 2011ae in MCG -03-30-19 = Psn J11544925-1651436
(2011) Howerton, S.; Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.; Sahu, D. K.; Arora, S.; Anto, P.
Report the Catalina Real-time Transient Survey's discovery of an apparent supernova in public images from the Catalina Sky Survey (CSS). SN 2011 UT R.A. (2000.0) Decl. Mag. Offset 2011ae Feb. 12.43 11 54 49.25 -16 51 43.6 15.5 4".9 W, 8".4 N Further unfiltered CCD magnitude estimates for 2011ae: Feb. 5.46 UT, [18.5 (CSS); 13.41, 15.3 (remotely with the LB3 0.35-m telescope at Rodeo, NM, U.S.A.). Drake writes that the presumed host galaxy has redshift z = 0.0060. The object was given the designation PSN J11544925-1651436 when posted by Drake on the Central Bureau's TOCP webpage, and based on the spectroscopy below is here assigned the final designation SN 2011ae. D. K. Sahu, S. Arora, and P. Anto, Indian Institute of Astrophysics, Bangalore, report that a low-resolution spectrogram (range 350-930 nm) of 2011ae, obtained on Feb. 21.75 UT with the Indian Astronomical Observatory's 2-m Himalayan Chandra Telescope (+ HFOSC), shows it to be a normal type-Ia supernova, a few days before maximum light. Using the SNID code of Blondin and Tonry (2007, Ap.J. 666, 1024), the spectrum of 2011ae is found to best match that of SN 1990N at about 5 days before maximum light. Adopting a recession velocity of 1813 km/s for the presumed host galaxy (de Vaucouleurs et al. 1991, Third Reference Catalogue of Bright Galaxies), MCG -03-30-19, the velocity corresponding to the Si II 635.5-nm absorption line is 12500 km/s....
Supernova 2011af = Psn J02255436+1023111
(2011) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.; Hsiao, E. Y.
Report the Catalina Real-time Transient Survey's discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images: SN 2011 UT R.A. (2000.0) Decl. Mag. Offset 2011af Jan. 11.09 2 25 54.36 +10 23 11.1 16.7 4" W, 1" N Further CSS magnitude estimates for 2011af: 2010 Dec. 10.21 UT, [19.0; 2011 Jan. 5.15, 16.5. This object was designated PSN J02255436+1023111 when posted at the Central Bureau's TOCP webpage by Drake, and based on the spectroscopy below is here designated SN 2011af. Kuiyun Huang and Yoichi Ohyama, Institute of Astronomy and Astrophysics, Academia Sinica; Chia-Jung Chuang, Yuji Urata, and Induk Lee, National Central University, Taiwan; and Eric Y. Hsiao, Lawrence Berkeley National Laboratory, report that the inspection of a CCD spectrum (range 400-900 nm), obtained on Jan. 29.5 UT with the 1.8-m Ritchey Cretien reflector and medium dispersion spectrometer at Bohyunsan Optical Astronomy Observatory, Korea, shows that SN 2011af is a type-IIn supernova. The spectrum consists of a flat continuum and prominent narrow emission lines of the Balmer series (H-alpha FWHM of about 1500 km/s), with the narrow peaks yielding a redshift of 0.064. The "superfit" program of Howell et al. (2005, Ap.J. 634, 1190) shows its spectrum to be an excellent match to that of SN 1988Z. SN 2011af is measured to have a magnitude r' about 17.2 on Feb. 7.46 UT with the 1-m telescope at the Lulin Observatory in Taiwan; this corresponds to an absolute magnitude of about -20, nearly a month past its initial discovery....
Supernova 2011ag in Pgc 11943 = Psn J03122655+1915064
(2011) Drake, A. J.; Djorgovski, S. G.; Mahabal, A.; Graham, M. J.; Williams, R.; Prieto, J. L.; Catelan , Marcio; Beshore, E. C.; Larson, S. M.; Christensen, E.; Koff, R. A.; Hsiao, E. Y.; Suzuki, N.; Nugent, P. E.
Report the Catalina Real-time Transient Survey's discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images: SN 2011 UT R.A. (2000.0) Decl. Mag. Offset 2011ag Feb. 25.15 3 12 26.55 +19 15 06.4 17.3 3".5 E, 20".0 N This object was designated PSN J03122655+1915064 on the Central Bureau's TOCP webpage, and is here designated SN 2011ag based on the spectroscopic report below. Further unfiltered CCD magnitudes for 2011ag: Feb. 4.11 UT, [20.4 (CSS); 27.089, 17.7 (R. A. Koff, Bennett, CO, U.S.A.; fourteen co-added 60-s images; position end figures 26s.55, 05".1). E. Y. Hsiao, N. Suzuki, and P. E. Nugent, Lawrence Berkeley National Laboratory, report that inspection of a CCD spectrum (range 350-980 nm), obtained on Feb. 27.25 UT with the 3-m Shane reflector (+ Kast) at Lick Observatory, shows that 2011ag is a type-Ia supernova. The "superfit" software of Howell et al. (2005, Ap.J. 634, 1190) identified the spectrum as that of a type-Ia supernova around a week past maximum. The redshift matches that of the reported host galaxy (PGC 11943): z = 0.032. The spectrum closely resembles that of SN 1998bu at 10 days past maximum (Jha et al. 1999, Ap.J. Suppl. 125, 73)....

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