J/AJ/133/2559 Compact radio sources in spiral galaxies. II. (Maddox+, 2007)
A study of compact radio sources in nearby face-on spiral galaxies.
II. Multiwavelength analyses of sources in M 51.
Maddox L.A., Cowan J.J., Kilgard R.E., Schinnerer E., Stockdale C.J.
<Astron. J., 133, 2559-2568 (2007)>
=2007AJ....133.2559M 2007AJ....133.2559M
ADC_Keywords: Radio sources ; Galaxies, nearby ; Cross identifications
Keywords: galaxies: individual (NGC 5194) - H II regions
radio continuum: galaxies - supernova remnants - X-rays: galaxies
Abstract:
We report the analysis of deep radio observations of the interacting
galaxy system M51 from the Very Large Array, with the goal of
understanding the nature of the population of compact radio sources in
nearby spiral galaxies. We detect 107 compact radio sources, 64% of
which have optical counterparts in a deep Hα Hubble Space Telescope
image. Thirteen of the radio sources have X-ray counterparts from a
Chandra observation of M51. We find that six of the associated Hα
sources are young supernova remnants (SNRs) with resolved shells. Most
of the SNRs exhibit steep radio continuum spectral indices consistent
with synchrotron emission. We detect emission from the Type Ic SN
1994I nearly a decade after explosion: the emission (160±22uJy/beam
at 20cm, 46±11uJy/beam at 6cm, α=-1.02±0.28) is consistent
with light-curve models for Type Ib/Ic supernovae. We detect X-ray
emission from the supernova; however, no optical counterpart is
present. We report on the analysis of the Seyfert 2 nucleus in this
galaxy, including the evidence for bipolar outflows from the central
black hole.
Description:
The 20cm observation was performed on 2002 April 5 for a total of 6hr
while the VLA was in A configuration. The 6cm observations were
performed in B configuration over several days in 2003 December and
2004 January during 22.5hr.
Objects:
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RA (2000) DE Designation(s)
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13 29 52.4 +47 11 41 M51 = NGC 5194
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 88 107 Positions, Flux Densities and Spectral Indices
of Point Sources in M51
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See also:
J/ApJ/252/102 : Radio sources in bright spiral galaxies. II. (Condon+, 1982)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [MCK2007] Source number
5 A1 --- n_[MCK2007] [b] Radio coincidence (1)
7- 8 I2 h RAh Hour of Right Ascension (J2000)
10- 11 I2 min RAm Minute of Right Ascension (J2000)
13- 17 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- Sign of the Declination (J2000)
19- 20 I2 deg DEd Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 29 F5.2 arcsec DEs Arcsecond of Declination (J2000)
31- 34 I4 uJy S20cm ? 20cm (1.5GHz) flux density in µJy/beam
36- 37 I2 uJy e_S20cm ? Error in S20cm in µJy/beam
39- 42 I4 uJy S6cm ? 6cm (5GHz) flux density in µJy/beam
44- 45 I2 uJy e_S6cm ? Error in S6cm in µJy/beam
47 A1 --- l_alpha Limit flag on spectral index
48- 53 F6.3 --- alpha Spectral Index (2)
55- 59 F5.3 --- e_alpha ? Error in spectral index
61- 76 A16 --- CXOU CXOU designation (JHHMMSS.s+DDMMSS) of
X-ray counterpart
78 I1 10+30W LX ? X-ray luminosity in 0.3-2keV band of
X-ray counterpart
80- 86 A7 --- XType Source classification based on X-ray colours
88 A1 --- n_CXOU [a] X-ray coincidence (1)
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Note (1): Note as follows:
a = Coincident with SN 1994I
b = Coincident with optical HII region
Note (2): Where Sν∝ν+α.
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History:
From electronic version of the journal
References:
Maddox et al. - Paper I. (M83) - 2006AJ....132..310M 2006AJ....132..310M
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 06-May-2009