J/ApJS/174/481 2LC Compact Radio Sources in the galactic center (Lazio+, 2008)
A VLA survey for compact radio sources in the galactic center.
Lazio T.J.W., Cordes J.M.
<Astrophys. J. Suppl. Ser., 174, 481-498 (2008)>
=2008ApJS..174..481L 2008ApJS..174..481L
ADC_Keywords: Cross identifications ; Pulsars ; Radio sources
Keywords: Galaxy: center - pulsars: general - surveys
Abstract:
We have used the VLA at 1.4GHz to survey the inner 2° of the
Galactic center for radio pulsar candidates. Because of the large
pulse broadening suffered by Galactic center radio pulsars, our
strategy has been to identify compact radio sources, without regard to
whether they are pulsed radio sources. We describe our survey and
present the catalog of 170 sources. Comparison with other radio
surveys of the area shows that just over half of these sources have
not been detected previously; this same comparison reveals 29 sources
that are not in higher frequency surveys, suggesting that the sources
are either variable or steep spectrum, and a comparable number of
sources in other surveys that should have been detected in this survey
but were not. Comparison with infrared surveys shows that 59 (35%)
sources have infrared counterparts and are likely to be HII regions.
Description:
Observations were conducted on 1996 October 24 and November 8 with the
VLA in the A configuration to observe the GC at 1.4 and 5GHz.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 65 170 The 2LC Catalog of Compact Radio Sources Toward
the Galactic Center (1.4GHz)
table3.dat 70 19 *The 2LC 5GHz Survey
table4.dat 78 83 Cross-Identifications
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Note on table3.dat: Table 3 is similar to that of Table 2 except that the
spectral index is tabulated between 1.4 and 5GHz
(S(ν)∝να) and the offset is not tabulated from
the phase center. The latter quantity is unimportant as the sources
were placed at or near the phase center.
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See also:
VIII/42 : Texas Survey of radio sources at 365MHz (Douglas+ 1996)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/ApJS/74/181 : Small-diameter radiosources catalogue (Zoonematkermani+, 1990)
J/ApJS/91/347 : A 5-GHz VLA Survey of the Galactic Plane (Becker+ 1994)
J/A+AS/136/571 : Pulsars identified from the NRAO VLA Sky Survey (Han+ 1999)
J/AJ/128/1646 : The Galactic Center region at 330MHz (Nord+, 2004)
J/ApJS/171/376 : MOJAVE. III. VLA 1.4GHz images (Cooper+, 2007)
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- 2LC Name (LLL.lll+B.bbb) (G1)
15- 16 I2 h RAh Hour of right ascension (J2000)
18- 19 I2 min RAm Minute of right ascension (J2000)
21- 26 F6.3 s RAs Second of right ascension (J2000)
28 A1 --- DE- Sign of the declination (J2000)
29- 30 I2 deg DEd Degree of declination (J2000)
32- 33 I2 arcmin DEm Arcminute of declination (J2000)
35- 39 F5.2 arcsec DEs Arcsecond of declination (J2000)
41- 46 F6.2 mJy Sp Peak intensity of source in mJy/beam (1)
48- 54 F7.2 mJy S Flux density of source (1)
56- 60 F5.2 arcsec theta Angular diameter of source (1)
62- 65 F4.1 arcmin Offset ? Angular offset of source from phase center
of field (table2 only) (1)
67- 70 F4.1 --- alpha ? Spectral index between 1.4 and 5GHz
(Snu∝nualpha) (table3 only) (1)
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Note (1): at 1.4GHz for table2, 5GHz for table3.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- 2LC Name (LLL.lll+B.bbb) (G1)
15- 20 F6.1 mJy S1.4 ? Flux density at 1.4GHz
22- 26 F5.2 arcsec theta ? Angular diameter
28- 40 A13 --- GPSR Name (LLL.lll+B.bbb) in Zoonematkermani
et al. 1990, Cat. J/ApJS/74/181 (1)
42- 45 F4.1 --- SRatio ? Flux density ratio
47- 59 A13 --- GPSR5 Name (LLL.lll+B.bbb) in Becker et al. 1994,
Cat. J/ApJS/91/347 (2)
61- 64 F4.1 --- alpha ? Spectral index between 1.4 and 5GHz
(Snu∝nualpha)
66- 73 A8 --- TXS Name (HHMM+DDd) in Texas Survey,
Douglas et al. 1996, Cat. VIII/42 (3)
75- 78 F4.1 --- alpha1 ? Spectral index between 0.37 and 1.4GHz
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Note (1): GPSR LLL.lll+BB.bbb in Simbad, zero-filled
Note (2): GPSR5 LLL.lll+B.bbb in Simbad, zero-filled
Note (3): TXS HHMM+DDdA in Simbad.
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Global Notes:
Note (G1): names based on galactic position are here zero-filled, e.g.
the source 0.352-0.068 is written 000.352-0.068
History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 16-Jun-2009