Mathematics – Logic
Scientific paper
Nov 1976
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1976apj...209..687d&link_type=abstract
Astrophysical Journal, vol. 209, Nov. 1, 1976, pt. 1, p. 687-692.
Mathematics
Logic
19
Cosmology, Decay Rates, Supernovae, Time Measurement, Astronomical Catalogs, Color, Stellar Luminosity, Time Constant
Scientific paper
The use of supernovae as cosmological clocks requires that proper allowance be made for absolute luminosity and color effects. The existence of two luminosity groups of Type I supernovae and, within each group, of a correlation between decay rate and absolute luminosity at maximum has been documented. It is shown that the proper form of the relationship is logarithmic, that regression effects must be taken into account for a correct reduction to standard conditions, and that it is essential to apply to the apparent decay rates another correction allowing for the second-order or differential K-effect arising from the rapid color evolution of Type I supernovae during the first month past maximum. Calculations of K-corrections are presented for photographic light curves using a realistic approximation of the U-B, B-V color evolution for durations not exceeding 33 days and z not exceeding 0.15, from which are derived the rate of change dK/dt and the corresponding correction factor to the time scale for decay. An application to data for 36 supernovae (z less than 0.06) shows that these corrections reduce the scatter in the (t, z)-diagram and yield a better-defined slope in the decay time-redshift relation.
de Vaucouleurs Gerard
Pence William D.
No associations
LandOfFree
Type I supernovae as cosmological clocks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Type I supernovae as cosmological clocks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Type I supernovae as cosmological clocks will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1724914