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J/A+A/319/33        Identification of X-ray sources around Seyferts (Arp 1997)

Identification of X-ray sources <1° from Seyfert galaxies. Arp H. <Astron. Astrophys. 319, 33 (1997)> =1997A&A...319...33A (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, Seyfert ; X-ray sources Keywords: galaxies: Seyfert; BL Lac Objects - quasars: general - X-rays: galaxies Abstract: Excess numbers of X-ray sources around bright Seyfert galaxies have been demonstrated with significances of association up to 7.4-sigma (Radecke, 1997A&A...319...18R). The optical identification of these sources is shown here to be predominantly blue stellar objects (BSO's) of which some are already catalogued as quasars. Excluding the two brightest Seyferts, a subset of 24 with apparent magnitudes between 8.04≤BTo,i≤12.90mag. show a minimum excess of >46 bright X-ray sources. These excess X-ray sources are generally distributed between 10'<r<40' and 12 of the Seyferts show conspicuous pairs of X-ray sources across their active nuclei. Additional pairing and alignment of sources is seen for the remaining Seyferts. Among the paired X-ray sources, 53 have been identified as BSO's. Some double and multiple BSO's have been identified which are candidates for groups and associations of quasars. Some groups are well aligned and some centered on small blue galaxies. Four previously known BL Lac objects fall close enough to the Seyferts in this sample to confirm, at a significance level of 1-2x10-9, a previously reported association of BL Lac objects with bright, low redshift galaxies. Objects: -------------------------------------------- RA (2000) DE Designation(s) -------------------------------------------- 12 17 09.8 +07 11 29 NGC 4235 11 06 47.4 +72 34 07 NGC 3516 13 42 08.3 +35 39 15 NGC 5273 14 17 59.5 +25 08 13 NGC 5548 -------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3 85 33 Position of optically identified X-ray Sources table3.tex 83 59 TeX version of table3
Byte-by-byte Description of file: table3
Bytes Format Units Label Explanations
1- 7 A7 --- Gal Galaxy name 9- 14 F6.1 ct/ks C Counts of the source in the .5-20keV band (1) 15 A1 --- m_C [NS] Multiplicity index no C 17- 18 I2 h RAh Right ascension (J2000) 20- 21 I2 min RAm Right ascension (J2000) 23- 26 F4.1 s RAs Right ascension (J2000) 27 A1 --- u_RAs Uncertainty flag on right ascension 28 A1 --- DE- Declination sign 29- 30 I2 deg DEd Declination (J2000) 32- 33 I2 arcmin DEm Declination (J2000) 35- 36 I2 arcsec DEs Declination (J2000) 37 A1 --- u_DEs Uncertainty flag on declination 38 A1 --- n_Emag [B] B when Emag is Bmag 39 A1 --- l_Emag [~] Limit flag on Emag 40- 43 F4.1 mag Emag ? E magnitude or B magnitude if n_Emag = B 45 A1 --- l_O-E Limit flag on O-E 46- 49 F4.2 mag O-E ? O-E color index 50 A1 --- n_O-E [b] b for blue 52- 58 A7 --- Ident Identification 60- 63 F4.1 arcsec DELTAx ? X optical identification position with respect to the X-ray position (2) 65- 67 I3 arcsec DELTAy ? Y optical identification position with respect to the X-ray position (2) 69- 85 A17 --- Rem Remarks
Note (1): Each map was inspected for patterns of pairs or alignments of sources across the central Seyfert. The sources which made up these patterns were then identified by their C=cts/ks values and are referred to by these numbers. Note (2): + is East and - is West of the X-ray position + is North and - is South of the X-ray position

(End) Patricia Bauer [CDS] 24-Feb-1997
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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