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J/AJ/115/1253       Deep X-Ray Radio Blazar Survey (DXRBS). I. (Perlman+ 1998)

The Deep X-ray Radio Blazar Survey. I. Methods and first results. Perlman E.S., Padovani P., Giommi P., Sambruna R., Jones L.R., Tzioumis A., Reynolds J. <Astron. J. 115, 1253 (1998)> =1998AJ....115.1253P
ADC_Keywords: QSOs ; BL Lac objects ; Surveys ; X-ray sources ; Radio sources Keywords: BL Lacertae objects: general - quasars: general - radio continuum - surveys Abstract: We have undertaken a survey, the Deep X-Ray Radio Blazar Survey (DXRBS), of archived, pointed ROSAT Position Sensitive Proportional Counter data for blazars by correlating the ROSAT WGACAT database with several publicly available radio catalogs, restricting our candidate list to serendipitous flat radio spectrum sources (αr≤0.70, where Sν∝νr_^). We discuss our survey methods, identification procedure, and first results. Our survey is found to be 95% efficient at finding flat-spectrum radio-loud quasars (FSRQs; 59 of our first 85 identifications) and BL Lacertae objects (22 of our first 85 identifications), a figure that is comparable to or greater than that achieved by other radio and X-ray survey techniques. The identifications presented here show that all previous samples of blazars (even when taken together) did not representatively survey the blazar population, missing critical regions of (LX, LR) parameter space within which large fractions of the blazar population lie. Particularly important is the identification of a large population of FSRQs (≥25% of DXRBS FSRQs) with ratios of X-ray to radio luminosity ≥10-6rx≤0.78). In addition, as a result of our greater sensitivity, the DXRBS has already more than doubled the number of FSRQs in complete samples with 5GHz (radio) luminosities between 1031.5 and 1033.5ergs/s/Hz, and fills in the region of parameter space between X-ray-selected and radio-selected samples of BL Lac objects. The DXRBS is the very first sample to contain statistically significant numbers of blazars at low luminosities, approaching what should be the lower end of the FSRQ luminosity function. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 116 102 Positional information table4.dat 90 102 Newly identified objects table6.dat 76 97 Previously identified blazars notes.dat 80 182 Individual notes
See also: IX/12 : The WGACAT version of ROSAT sources (White+ 1995) VIII/38 : The Parkes-MIT-NRAO 4.85GHz (PMN) Surveys (Griffith+ 1993-1996) VIII/40 : GB6 catalog of radio sources at 4.85GHz (Gregory+ 1996) VIII/15 : Parkes Radio Sources Catalogue (PKSCAT90) (Wright+ 1990) J/MNRAS/323/757 : Deep X-Ray Radio Blazar Survey (DXRBS). II. (Landt+, 2001) Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 3 A3 --- --- [WGA] 5- 16 A12 --- 1WGA WGACAT name 18- 19 I2 h RAh WGACAT right ascension (J2000) 21- 22 I2 min RAm WGACAT right ascension (J2000) 24- 27 F4.1 s RAs WGACAT right ascension (J2000) 29 A1 --- DE- WGACAT declination sign 30- 31 I2 deg DEd WGACAT declination (J2000) 33- 34 I2 arcmin DEm WGACAT declination (J2000) 36- 37 I2 arcsec DEs WGACAT declination (J2000) 39- 42 F4.1 arcsec oWGA Offset from field center in X-ray 44- 45 I2 arcsec eWGA WGACAT error (1) 47- 48 I2 h RA1h PMN or GB6 right ascension (J2000) 50- 51 I2 min RA1m PMN or GB6 right ascension (J2000) 53- 56 F4.1 s RA1s PMN or GB6 right ascension (J2000) 58 A1 --- DE1- PMN or GB6 declination sign 59- 60 I2 deg DE1d PMN or GB6 declination (J2000) 62- 63 I2 arcmin DE1m PMN or GB6 declination (J2000) 65- 66 I2 arcsec DE1s PMN or GB6 declination (J2000) 68- 69 I2 h RA2h Optical Counterpart right ascension (J2000) 71- 72 I2 min RA2m Optical Counterpart right ascension (J2000) 74- 77 F4.1 s RA2s Optical Counterpart right ascension (J2000) 79 A1 --- DE2- Optical Counterpart declination sign 80- 81 I2 deg DE2d Optical Counterpart declination (J2000) 83- 84 I2 arcmin DE2m Optical Counterpart declination (J2000) 86- 87 I2 arcsec DE2s Optical Counterpart declination (J2000) 89- 96 A8 --- Source Source (2) 98-102 F5.2 arcsec Offset Absolute offset (X-O) value 104-105 I2 arcsec eCount Counterpart error 107-111 F5.2 arcsec Error Cumulative error 113-116 F4.2 --- o/e Ratio of Offset to Error
Note (1): WGACAT positional error circles. This was done as follows: WGACAT was cross-correlated with the Hipparcos Input Catalogue (Cat. I/196), and the offsets between the two databases were obtained for six bins of the distance from the WGACAT field center (0'-10', 10'-20', etc.). These values range from 13" (for the inner 10' of the PSPC field) to 53" (for the 50'-60' ring). Note (2): Source codes are: APM: APM survey GB6: Green Bank 6cm catalog, Cat. VIII/40 PMN: Parkes-MIT-NRAO catalog, Cat. VIII/27 ATCA: Austalian Telescope Compact Array, this paper NVSS: NRAO VLA Sky Survey, Condon et al., 1998AJ....115.1693C FIRST: FIRST project, Gregg et al., 1996AJ....112..407G; Laurent-Muehleisen et al., 1998, in prep. (see VIII/51)
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 3 A3 --- --- [WGA] 5- 16 A12 --- 1WGA WGACAT name 18- 22 F5.3 ct/s Crate ROSAT count rate 24- 31 E8.2 mW/m2 F(0.1-2.0) 0.1-2.0keV flux 33- 37 F5.3 uJy F1keV Flux density at 1keV 39- 44 F6.2 --- log(FX/FR) ? X-flux to radio-flux ratio 46- 49 I4 mJy F6cm ? Flux density at 6cm 51- 55 F5.2 --- SI ? Radio spectral index 57 A1 --- l_Bmag Limit flag on Bmag 58- 61 F4.1 mag Bmag ? B magnitude 63 A1 --- l_Rmag Limit flag on Rmag 64- 67 F4.1 mag Rmag ? R magnitude 69- 75 A7 --- Class Classification (1) 77- 81 F5.3 --- z ? Redsifht 82 A1 --- u_z [?] Uncertainty flag on z 84- 86 A3 --- Cat Other catalogs (2)
Note (1): Classification is coded as follws: RG: radio galaxy FSRQ: flat-spectrum radio-loud quasar SSRQ: steep-spectrum radio-loud quasar BL Lac: BL Lac object Note (2): Other catalogs are numbered as follows: 1: RASS Bright Source Catalog, Cat. IX/10 2: HBQS, Homogeneous Bright QSO Survey, Cat. J/A+AS/112/347 3: V Zwicky Catalog of Galaxies, Cat. VII/190 4: 4C, Fourth Cambridge Survey, Cat. VIII/4 5: Einstein Slew Survey, Elvis et al., 1992ApJS...80..257E 6: FIRST Bright Quasar Survey, See Cat. VIII/51 7: B3, Third Bologna Survey, Cat. VIII/37 8: Las Campanas Redshift Survey, Cat. VII/203
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Source name 17- 21 F5.3 ct/s Crate ROSAT count rate 23- 30 E8.2 mW/m2 F(0.1-2.0) 0.1-2.0keV flux 32- 37 F6.3 uJy F1keV Flux density at 1keV 39- 44 F6.2 --- log(FX/FR) X-flux to radio-flux ratio 46- 50 I5 mJy F6cm Flux density at 6cm 52- 56 F5.2 --- SI Radio spectral index 58- 61 F4.1 mag Vmag ? V magnitude 63- 68 A6 --- Class Classification (1) 70 A1 --- l_z Limit flag on z 71- 75 F5.3 --- z ? Redsifht 76 A1 --- u_z [?] Uncertainty flag on z
Note (1): Classification is: RG: radio galaxy FSRQ: flat-spectrum radio-loud quasar BL Lac: BL Lac object
Byte-by-byte Description of file: notes.dat
Bytes Format Units Label Explanations
1- 3 A3 --- --- [WGA] 5- 16 A12 --- 1WGA WGACAT name (repeated of more than 1 line) 18- 80 A63 --- Note Text of the note
History: * 11-Aug-1998: From AJ electronic version * 18-Apr-2005: in the notes, corrected the name WGA J1057.7-7724 into J1057.6-7724 and in the tables 3 and 4, corrected the name J2317.4-4213 into J2317.9-4213
(End) Patricia Bauer [CDS] 11-Aug-1998
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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