SN?2005ap: A Most Brilliant Explosion

摘要: We present unfiltered photometric observations with ROTSE-III and optical spectroscopic follow-up HET the Keck telescope of most luminous supernova yet identified, SN 2005ap. The spectra taken about 3 days before 6 after maximum light show narrow emission lines (likely originating in dwarf host) absorption at a redshift z = 0.2832, which puts peak magnitude -22.7 ± 0.1 absolute. Broad P Cygni features corresponding to Hα, C III, N O III are further detected photospheric velocity ~20,000 km s-1. Unlike other highly supernovae such as 2006gy 2006tf that slow evolution, curve 2005ap indicates 1-3 week rise followed by relatively rapid decay. also lack distinct peaks from moderately broadened (FWHM ~2000 s-1) Balmer seen 2006tf. briefly discuss origin extraordinary luminosity strong interaction may be expected pair instability eruption or GRB-like engine encased H/He envelope.