J/ApJ/786/130 Catalog of M31 SNR candidates (Lee+, 2014)
A new optical survey of supernova remnant candidates in M31.
Lee J.H., Lee M.G.
<Astrophys. J., 786, 130 (2014)>
=2014ApJ...786..130L 2014ApJ...786..130L (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Supernova remnants ; Photometry, H-alpha ;
Stars, diameters ; Morphology ; Stars, OB ; H II regions
Keywords: galaxies: individual: M31 - galaxies: ISM - ISM: supernova remnants
Abstract:
We present a survey of optically emitting supernova remnants (SNRs) in
M31 based on Hα and [S II] images in the Local Group Survey.
Using these images, we select objects that have [S II]:Hα>0.4
and circular shapes. We identify 156 SNR candidates, of which 76 are
newly found objects. We classify these SNR candidates according to two
criteria: the SNR progenitor type (Type Ia and core-collapse (CC) SNRs)
and the morphological type. Type Ia and CC SNR candidates make up 23%
and 77%, respectively, of the total sample. Most of the CC SNR candidates
are concentrated in the spiral arms, while the Type Ia SNR candidates
are rather distributed over the entire galaxy, including the inner
region. The CC SNR candidates are brighter in Hα and [S II] than
the Type Ia SNR candidates. We derive a cumulative size distribution
of the SNR candidates, finding that the distribution of the candidates
with 17<D<50 pc is fitted well by a power law with the power-law index
α=2.53±0.04. This indicates that most of the SNR candidates
identified in this study appear to be in the Sedov-Taylor phase. The
[S II]:Hα distribution of the SNR candidates is bimodal, with
peaks at [S II]:Hα∼0.4 and∼0.9. The properties of these SNR
candidates vary little with the galactocentric distance. The Hα
and [S II] surface brightnesses show a good correlation with the X-ray
luminosity of the SNR candidates that are center-bright.
Description:
We used the M31 images obtained from the LGS (Massey et al. 2006,
J/AJ/131/2478). It contains 10 overlapping fields across the disk of
M31. Each field has an approximate angular size of 36'x36', and the
entire survey covers 2.2 deg2 of M31. The pixel scale is 0.27" per
pixel, with an average point-spread function FWHM of 1". We used the
images in Hα, [S II], and continuum bands that can be used to
subtract most of the stellar emission. The Hα filter is sufficiently
broad to include some [N II] emission as well, but we will refer to
it as the Hα image.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
00 42 44.33 +41 16 07.5 M31 = NAME Andromeda Galaxy
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 56 154 A Catalog of Previous M31 SNR Candidates
Rejected in This Study
table3.dat 71 156 A Catalog of M31 SNR Candidates
--------------------------------------------------------------------------------
See also:
J/A+AS/114/215 : New SNR candidates in M31 (Magnier+, 1995)
J/AJ/131/2478 : M31 and M33 UBVRI photometry (Massey+, 2006)
J/ApJ/795/170 : Sample SNRs for M31 and M33 (Jennings+, 2014)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Source identifier (G1)
11- 20 F10.7 deg RAdeg Right Ascension in decimal degrees (J2000) (G2)
22- 30 F9.6 deg DEdeg Declination in decimal degrees (J2000) (G2)
32- 36 F5.2 [10-7W] logLHa Log of Hα luminosity; erg/s (G3)
38- 42 F5.2 [10-7W] logLSII Log of [S II] luminosity; erg/s (G3)
44- 48 F5.1 pc Dia Diameter calculated using 1"=3.63 pc
50- 53 F4.2 --- Ratio Ratio of [S II] to Hα
55- 56 A2 --- Class Classification (1)
--------------------------------------------------------------------------------
Note (1): Classification as follows:
H = H II regions with [S II]:Hα<0.4;
HO = H II regions with 0.4<[S II]:Hα<0.6 and blue stars inside;
S = Superbubbles (Larger than D=100 pc and a number of blue stars inside);
D = Diffuse ionized gas ([S II]:Hα>0.8, but very low surface
brightnesses).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ID [1/156] Index number
5- 14 F10.7 deg RAdeg Right Ascension in decimal degrees (J2000) (G2)
16- 24 F9.6 deg DEdeg Declination in decimal degrees (J2000) (G2)
26- 30 F5.2 [10-7W] logLHa Log of Hα luminosity; erg/s (G3)
32- 36 F5.2 [10-7W] logLSII Log of [S II] luminosity; erg/s (G3)
38- 42 F5.1 pc Dia Diameter calculated using 1"=3.63 pc (1)
44- 47 F4.2 --- Ratio Ratio of [S II] to Hα
49- 50 A2 --- Morph Morphology type; see text
52- 53 I2 --- N(OB) Number of OB stars (2)
55 I1 --- N(HII) Number of H II regions (3)
57- 58 A2 --- PType Progenitor type (4)
60- 71 A12 --- Com Comments (G1)
--------------------------------------------------------------------------------
Note (1): For d=750 kpc.
Note (2): Located between the boundary of each SNR candidate and 100 pc
from the center of each SNR.
Note (3): With L>1036 erg/s located between the boundary of each SNR
candidate and 100 pc from the center of each SNR.
Note (4): Progenitor type as follows:
CC = Core collapse;
Ia = Type Ia.
--------------------------------------------------------------------------------
Global notes:
Note (G1): Source as follows:
D80 = Dodorico et al. (1980A&AS...40...67D 1980A&AS...40...67D), D80.NN, DDB 1-NN in Simbad
BA = Blair et al. (1981ApJ...247..879B 1981ApJ...247..879B), BANNN, BA 1-NNN in Simbad
K = Braun & Walterbos (1993A&AS...98..327B 1993A&AS...98..327B), KNNN, [WB92a] NNN in Simbad
M95 = Magnier et al. (1995, J/A+AS/114/215) M95-N-NNN, [MPV95] N-NNN in Simbad
Note (G2): Measured in the Hα image.
Note (G3): Calculated using L=4πd2*flux for d=750 kpc.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 22-Jun-2017