Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Epochs of Maximum Light and Bolometric Light Curves of Type Ia
  Supernovae   We present empirical fits to the UBVRI light curves of type Ia supernovae.
These fits are used to objectively evaluate light curve parameters. We find
that the relative times of maximum light in the filter passbands are very
similar for most objects. Surprisingly the maximum at longer wavelengths is
reached earlier than in the B and V light curves. This clearly demonstrates the
complicated nature of the supernova emission. Bolometric light curves for a
small sample of well-observed SNe Ia are constructed by integration over the
optical filters. In most objects a plateau or inflection is observed in the
light curve about 20-40 days after bolometric maximum. The strength of this
plateau varies considerably among the individual objects in the sample.
Furthermore the rise times show a range of several days for the few objects
which have observations early enough for such an analysis. On the other hand,
the decline rate between 50 and 80 days past maximum is remarkably similar for
all objects, with the notable exception of SN 1991bg. The similar late decline
rates for the supernovae indicate that the energy release at late times is very
uniform; the differences at early times is likely due to the radiation
diffusing out of the ejecta. With the exception of SN 1991bg, the range of
absolute bolometric luminosities of SNe Ia is found to be at least a factor of
2.5. The nickel masses derived from this estimate range from 0.4 to 1.1 Msun.
It seems impossible to explain such a mass range by a single explosion
mechanism, especially since the rate of gamma-ray escape at late phases seems
to be very uniform.

24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat