Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transparent Helium in Stripped Envelope Supernovae   Using simple arguments based on photometric light curves and velocity
evolution, we propose that some stripped envelope supernovae (SNe) show signs
that a significant fraction of their helium is effectively transparent. The
main pieces of evidence are the relatively low velocities with little velocity
evolution, as are expected deep inside an exploding star, along with
temperatures that are too low to ionize helium. This means that the helium
should not contribute to the shaping of the main SN light curve, and thus the
total helium mass may be difficult to measure from simple light curve modeling.
Conversely, such modeling may be more useful for constraining the mass of the
carbon/oxygen core of the SN progenitor. Other stripped envelope SNe show
higher velocities and larger velocity gradients, which require an additional
opacity source (perhaps the mixing of heavier elements or radioactive nickel)
to prevent the helium from being transparent. We discuss ways in which similar
analysis can provide insights into the differences and similarities between SNe
Ib and Ic, which will lead to a better understanding of their respective
formation mechanisms.

27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics