Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Expanding Photospheres of Type II Supernovae and the Extragalactic
  Distance Scale   We use the Expanding Photosphere Method to determine distances to 10 type II
supernovae. The effects of asymmetries, extinction, and flux dilution are
explored. Using empirical evidence and time-independent, spherical models which
treat H and He in non-LTE, we show that blackbody corrections caused by flux
dilution are small for type II supernovae in the infrared, and in the optical
when their color temperatures are less than 6000~K. The extinction to a type
II-P supernova can be estimated from its light curve: the uncertainty
introduced into a distance measurement due to extinction is usually less than
10\%. Correcting for extinction and flux dilution we derive distances to 10
supernovae: SN 1968L, SN 1969L, SN 1970G, SN 1973R, SN 1979C, SN 1980K, SN
1987A, SN 1988A, SN 1990E, and SN 1990ae. The distance measurements span a wide
range, 50 kpc to 120 Mpc, which is unique among the methods for establishing
the extragalactic distance scale. The distances measured to SN 1970G in M101
and SN 1987A in the LMC are in good agreement with distances determined from
Cepheid variable stars. Our distance to the Virgo Cluster, 22 +- 3 Mpc, is
larger than recent distances estimates made using surface brightness
fluctuations, planetary nebula luminosity functions, and the Tully-Fisher
method. Using the distances determined from these type II supernovae we derive
a value of $H_0 = 60 \pm 10$ km sec$^{-1}$Mpc$^{-1}$. This value is subject to
errors caused by local deviations in the Hubble flow, but will soon be improved
by applying the Expanding Photosphere Method to several distant type II
supernovae.

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The categories of this paper are: stat
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
1
The categories of this paper are: cs