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J/ApJ/658/99        Pairs of QSO in SDSS-DR4                  (Myers+, 2007)

Clustering analyses of 300,000 photometrically classified quasars. II. The excess on very small scales. Myers A.D., Brunner R.J., Richards G.T., Nichol R.C., Schneider D.P., Bahcall N.A. <Astrophys. J., 658, 99-106 (2007)> =2007ApJ...658...99M
ADC_Keywords: Surveys ; QSOs ; Redshifts ; Photometry, SDSS Keywords: cosmology: observations - large-scale structure of universe - quasars: general - surveys Abstract: We study quasar clustering on small scales, modeling clustering amplitudes using halo-driven dark matter descriptions. From 91 pairs n scales <35h-1kpc, we detect only a slight excess in quasar clustering over our best-fit large-scale model. Integrated across all redshifts, the implied quasar bias is bQ=4.21±0.98 (bQ=3.93±0.71) at ∼18h-1kpc (∼28h-1kpc). Description: The "KDE" data sample used in this paper, which is constructed using the kernel density estimation (KDE) technique of Richards et al. (2004, Cat. J/ApJS/155/257), is detailed in Paper I, Myers et al. (2006ApJ...638..622M). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 196 111 Quasar pairs in the DR4 KDE catalog with separations <0.1'
See also: II/282 : The SDSS Photometric Catalog, Release 6 (Adelman-McCarthy+, 2007) J/AJ/131/1 : Binary quasars in the SDSS (Hennawi+, 2006) J/A+A/459/L1 : Supercluster sample from SDSS DR4 (Einasto+, 2006) J/A+A/471/17 : SDSS-DR4 nearby clusters global properties (Aguerri+, 2007) : SDSS-DR4 Home Page Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 4 A4 --- --- [SDSS] 5- 23 A19 --- SDSS1 First component of Quasar pair name, 25- 26 I2 h RAh Pair1 Hour of Right Ascension (J2000) 28- 29 I2 min RAm Pair1 Minute of Right Ascension (J2000) 31- 35 F5.2 s RAs Pair1 Second of Right Ascension (J2000) 37 A1 --- DE- Pair1 Sign of the Declination (J2000) 38- 39 I2 deg DEh Pair1 Degree of Declination (J2000) 41- 42 I2 arcmin DEm Pair1 Arcminute of Declination (J2000) 44- 47 F4.1 arcsec DEs Pair1 Arcsecond of Declination (J2000) 49- 53 F5.2 --- umag1 Pair1 SDSS u band magnitude (1) 55- 59 F5.2 --- gmag1 Pair1 SDSS g band magnitude (1) 61- 64 F4.2 --- zph1l Pair1 photometric redshift range minimum 66- 70 F5.3 --- zph1m Pair1 photometric redshift range midpoint 72- 75 F4.2 --- zph1u Pair1 photometric redshift range maximum 77- 81 F5.3 --- zsp1 ? Pair1 spectroscopic redshift 83- 88 A6 --- f_zsp1 Flag on zspec1 (2) 89- 93 F5.3 --- zsp1b ? Second Pair1 spectroscopic redshift 94 A1 --- r_zsp1b [b] Reference for zspecb (3) 96- 99 A4 --- --- [SDSS] 100-118 A19 --- SDSS2 Second component of Quasar pair name, 120-121 I2 h RA2h Pair2 Hour of Right Ascension (J2000) 123-124 I2 min RA2m Pair2 Minute of Right Ascension (J2000) 126-130 F5.2 s RA2s Pair2 Second of Right Ascension (J2000) 132 A1 --- DE2- Pair2 Sign of the Declination (J2000) 133-134 I2 deg DE2h Pair2 Degree of Declination (J2000) 136-137 I2 arcmin DE2m Pair2 Arcminute of Declination (J2000) 139-142 F4.1 arcsec DE2s Pair2 Arcsecond of Declination (J2000) 144-148 F5.2 --- umag2 Pair2 SDSS u band magnitude (1) 150-154 F5.2 --- gmag2 Pair2 SDSS g band magnitude (1) 156-159 F4.2 --- zph2l Pair2 photometric redshift range minimum 161-165 F5.3 --- zph2m Pair2 photometric redshift range midpoint 167-170 F4.2 --- zph2u Pair2 photometric redshift range maximum 172-176 F5.3 --- zsp2 ? Pair2 spectroscopic redshift 178-183 A6 --- n_zsp2 Note about Pair2 (2) 184-188 F5.3 --- zsp2b ? Pair2 alternative spectroscopic redshift 190 A1 --- r_zsp2b [b] Reference for zspec2b (3) 192-195 F4.2 arcsec Delta Angular separation of Quasar pair 196 A1 --- f_Delta [*] Objects in high absorption regions (Ag>21) have a higher probability of being stars.
Note (1): Photometry is "as observed" (not been corrected for Galactic extinction). Note (2): The reference follows spectroscopic redshift with the following code: a = Source: DR4 Catalog Archive Server (e.g., likely Schneider et al., 2005AJ....130..367S, Cat. VII/243) b = Source: Hennawi et al. (2006, Cat. J/AJ/131/1) c = Source: Sramek & Weedman (1978ApJ...221..468S), Djorgovski & Spinrad (1984, in in ASP Conf. Ser. 21, 349) d = Probable binary quasar-starburst (Brotherton et al., 1999ApJ...520L..87B) * = Objects in Galactic regions with absorption Ag>0.21. These were not included in our main analysis, as it is known (see, the Appendixes of Paper I, Myers et al. (2006ApJ...638..622M)) that such objects have a higher probability of being stars ? = Object with low confidence redshift ?? = High probability lens (as recorded at ) Note (3): b = the alternative redshift from Hennawi et al. (2006, Cat. J/AJ/131/1) is provided where there is a redshift available from this reference in addition to that available in the DR4 CAS.
History: From electronic version of the journal References: Myers et al., Paper I 2006ApJ...638..622M
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 09-Jan-2009
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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