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J/AJ/112/62         Quasar absorption-line systems (Tanner+ 1996)

A study of quasar absorption-line systems with IRAS Tanner A.M., Bechtold J., Walker C.E., Black J.H., Cutri R.M. <Astron. J. 112, 62 (1996)> =1996AJ....112...62T
ADC_Keywords: QSOs ; Redshifts ; Spectra, infrared Abstract: A survey of quasar absorbers was conducted using the Infrared Astronomical Satellite (IRAS) database. Quasars with known intervening absorption-line systems and broad absorption line (BAL) QSOs were selected primarily from Junkkarinen et al. (1991ApJS...77..203J). Of the 570 quasars with IRAS data, 52 showed 3σ or better detections in at least one band in SCANPI analysis. The origin of the IRAS flux could be from the absorption-line systems, other galaxies, or the quasar itself. The spectral energy distributions for quasars detected in the absorption-line sample and BAL QSOs were found to be redder than those of two control samples which suggests that some of the IRAS flux may arise in dust associated with the intervening galaxies. IRAS SUPERSCANPI processing was carried out for 77 quasars with known MgII absorption at Zabs<1 to investigate the ensemble far-infrared properties of these objects. SUPERSCANPI processing evaluates the median flux for many different positions on the sky, resulting in an improvement in the effective sensitivity. A control sample consisting of objects with no MgII absorption known at Zabs<1 but with the same distribution of absolute V-magnitude, Zem and radio-loud fraction for the background quasars was also processed. The MgII sample was detected at 3σ or better in all four IRAS bands with a significantly larger flux than the control sample at 60µm and 100µm. If this far-infrared emission is from the absorber galaxies, then the far-infrared luminosity of the composite MgII absorber was found to be comparable to that of a starbursting galaxy, although such a high star-formation rate is inconsistent with the optical and near-infrared colors of low-redshift MgII systems. Four of the quasars with individual IRAS detections have intervening galaxies identified with the MgII absorption-lines. The spectral energy distributions of these galaxies imply far-infrared luminosities in excess of what Arp 220 would give at their redshifts. While all the external evidence suggests that the detection of far-infrared emission from the absorber sample may not be connected to the presence of the MgII absorber, we discuss future observations which may help explain our results. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 32 38 Additional quasar in absorption-line (AL) sample, not in JHB (Cat. J/ApJS/77/203) table2.dat 32 34 Damped Lyα sample table3.dat 173 46 IRAS ADDSCAN detections table4.dat 173 6 BAL QSO's detected with IRAS ADDSCAN analysis table5.dat 42 77 Low redshift MgII absorption line sample table6.dat 48 77 Control sample with no MgII absorption for Zabs<1
Byte-by-byte Description of file: table1.dat table2.dat
Bytes Format Units Label Explanations
1- 8 A8 --- QSO Quasar name 9 A1 --- r_QSO Reference (1) 11- 15 F5.3 --- zem Emission redshift 17- 21 F5.3 --- zabs ? Absorption redshift 23- 27 F5.2 mag Vmag ? V magnitude from Hewitt & Burbidge (1993ApJS...87..451H) 29- 32 F4.2 --- RL ? Radio loudness (G1)
Note (1): References as follows: a = Steidel & Sargent (1992ApJS...80....1S) b = Aldcroft et al. (1994ApJS...93....1A) c = Lanzetta et al. (1991ApJS...77....1L) d = Junkkarinen et al. (1991, Cat. J/ApJS/77/203) e = White et al. (1993ApJ...407..456W) f = Turnshek et al. (1989ApJ...344..567T) g = Wolfe et al. (1986ApJS...61..249W) h = Francis & Hewitt (1993AJ....105.1633F)
Byte-by-byte Description of file: table3.dat table4.dat
Bytes Format Units Label Explanations
1- 8 A8 --- QSO Quasar name 9- 11 A3 --- Note Individual note (1) 13- 17 F5.3 --- zem ? Emission redshift 19- 23 F5.2 mag Vmag ? V magnitude 25- 32 F8.5 --- zabs ? Absorption redshift 34- 35 I2 h RAh Right ascension (1950.0) 37- 38 I2 min RAm Right ascension (1950.0) 40- 44 F5.2 s RAs Right ascension (1950.0) 46 A1 --- DE- Declination 47- 48 I2 deg DEd Declination (1950.0) 50- 51 I2 arcmin DEm Declination (1950.0) 53- 56 F4.1 arcsec DEs Declination (1950.0) 58 A1 --- l_S12um Limit flag on 12um 59- 63 F5.3 Jy S12um IRAS flux at 12um (2) 64- 68 F5.3 Jy e_S12um ? rms uncertainty on S12um 70 A1 --- l_S25um Limit flag on 25um 71- 75 F5.3 Jy S25um IRAS flux at 25um (2) 77- 81 F5.3 Jy e_S25um ? rms uncertainty on S25um 83 A1 --- l_S60um Limit flag on 60um (2) 84- 88 F5.3 Jy S60um IRAS flux at 60um 89- 93 F5.3 Jy e_S60um ? rms uncertainty on S60um 94 A1 --- l_S100um Limit flag on 100um (2) 95-100 F6.3 Jy S100um IRAS flux at 100um 101-104 F4.2 Jy e_S100um ? rms uncertainty on S100um 106-109 F4.2 --- RL ? Radio loudness, see also n_RL (G1) 110 A1 --- n_RL [OBj] Note about RL, and classification (3) 112-117 F6.4 --- zabs2 ? Second absorption redshift 119-124 F6.4 --- zabs3 ? Second absorption redshift 126-131 F6.4 --- zabs4 ? Second absorption redshift 133-138 F6.4 --- zabs5 ? Second absorption redshift 140-145 F6.4 --- zabs6 ? Second absorption redshift 147-152 F6.4 --- zabs7 ? Second absorption redshift 154-159 F6.4 --- zabs8 ? Second absorption redshift 161-166 F6.4 --- zabs9 ? Second absorption redshift 168-173 F6.4 --- zabs10 ? Second absorption redshift
Note (1): Notes as follows; c = galaxies or quasars in vicinity visible on Palomar Sky Survey. d = UGC 439, IRAS source is 45 arcseconds northwest of quasar. e = bright stars nearby visible on Palomar Sky Survey. f = IRAS source is 1 arcminute northwest of quasar. g = IRAS source is 30 arcseconds southeast of quasar. h = IRAS source is 1 arcminute north of quasar. i = NGC 3067, IRAS source is 2 arcminutes southwest of quasar. k = IRAS source is 1 arcminute south of quasar. l = NGC 6045. m = ESO 400-G012. Note (2): 3 σ upper limits given when not detected Note (3): Note as follows: j = RL based on 5 GHz flux densities from Kellerman et al. (1994AJ....108.1163K). B = BL Lac O = OVV
Byte-by-byte Description of file: table5.dat table6.dat
Bytes Format Units Label Explanations
1- 9 A9 --- QSO Quasar name 10- 12 A3 --- n_QSO Individual note (1) 15- 20 F6.4 --- zem ? Emission redshift 22- 27 F6.4 --- zabs ? Absorption redshift 29- 33 F5.2 mag Vmag V magnitude 36- 40 F5.3 --- RL ? Radio loudness 42 I1 --- Ref ? References, for table6 only (2)
Note (1): Note as follows: a = Objects with individual IRAS detections b = Removed for the control list for SUPERSCANPI without IRAS detections Note (2): Note as follows: 1 = Aldcroft et al. (1994ApJS...93....1A) 2 = Steidel & Sargent (1992ApJS...80....1S) 3 = Barthel et al. (1990A&AS...82..339B)
Global Notes: Note (G1): RL=log[fv(5GHz)/fv(V)], where fv(5GHz) is the radio flux density at 5GHz and [fv(V) is the V band flux density, based on 5GHz flux densities from Veron-Cetty & Veron (1987, See Cat. VII/188)
History: Prepared via OCR at CDS. In table6, for QSO 0736-0620, V=718.5 in the printed version, we change this value in 18.5 in the electronic table
(End) James Marcout, Patricia Bauer [CDS] 17-Jun-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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