Maqola

VERY EARLY ULTRAVIOLET AND OPTICAL OBSERVATIONS OF THE TYPE Ia SUPERNOVA 2009ig

R. J. FoleyHarvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA; [email protected]Peter ChallisHarvard UniversityA. V. FilippenkoDepartment of Astronomy, University of California, Berkeley, CA 94720-3411, USAM. GaneshalingamDepartment of Astronomy, University of California, Berkeley, CA 94720-3411, USAV. La ParolaNASA Goddard Space Flight Center, Greenbelt, MD 20771, USAWenyu LiDepartment of Astronomy, University of California, Berkeley, CA 94720-3411, USAG. H. MarionHarvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA; [email protected]J. M. SilvermanDepartment of Astronomy, University of California, Berkeley, CA 94720-3411, USARachael L. BeatonDepartment of Astronomy, University of Virginia, Charlottesville, VA 22904-4325, USAVardha N. BennertDepartment of Physics, University of California, Santa Barbara, CA 93106-9530, USAS. B. CenkoDepartment of Astronomy, University of California, Berkeley, CA 94720-3411, USAM. ChildressDepartment of Physics, University of California, 366 LeConte Hall, Berkeley, CA 94720-7300, USAPuragra GuhathakurtaUCO/Lick Observatory, University of California, Santa Cruz, CA 95064, USALinhua JiangSteward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USAJason S. KaliraiSpace Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USAR. KirshnerHarvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA; [email protected]Alan StocktonInstitute for Astronomy, University of Hawaii, Honolulu, HI 96822, USAErik TollerudCenter for Cosmology, Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697, USAJozsef VinkoAstronomy Department, University of Texas, Austin, TX 78712, USAJ. Craig WheelerAstronomy Department, University of Texas, Austin, TX 78712, USAJong-Hak WooAstronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul, 151-742, Korea

2011en

ABI

Annotatsiya

Supernova (SN) 2009ig was discovered 17 hr after explosion by the Lick Observatory Supernova Search, promptly classified as a normal Type Ia SN (SN Ia), peaked at V = 13.5 mag, and was equatorial, making it one of the foremost SNe for intensive study in the last decade. Here, we present ultraviolet (UV) and optical observations of SN 2009ig, starting about 1 day after explosion until around maximum brightness. Our data include excellent UV and optical light curves, 25 premaximum optical spectra, and 8 UV spectra, including the earliest UV spectrum ever obtained of an SN Ia. SN 2009ig is a relatively normal SN Ia, but does display high-velocity ejecta—the ejecta velocity measured in our earliest spectra (v –23, 000 km s–1 for Si II λ6355) is the highest yet measured in an SN Ia. The spectral evolution is very dramatic at times earlier than 12 days before maximum brightness, but slows after that time. The early-time data provide a precise measurement of 17.13 ± 0.07 days for the SN rise time. The optical color curves and early-time spectra are significantly different from template light curves and spectra used for light-curve fitting and K-corrections, indicating that the template light curves and spectra do not properly represent all SNe Ia at very early times. In the age of wide-angle sky surveys, SNe like SN 2009ig that are nearby, bright, well positioned, and promptly discovered will still be rare. As shown with SN 2009ig, detailed studies of single events can provide significantly more information for testing systematic uncertainties related to SN Ia distance estimates and constraining progenitor and explosion models than large samples of more distant SNe.

Hali tarjima qilinmagan

Identifikatorlar

DOI: 10.1088/0004-637x/744/1/38

Iqtiboslar va manbalar

2 ta iqtibos0 ta foydalanilgan manba

Koʻrsatkichlar — AkademScholar