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J/ApJ/569/23        Optical polarisation of 2MASS QSOs       (Smith+, 2002)

The optical polarization of near-infrared-selected quasi-stellar objects. Smith P.S., Schmidt G.D., Hines D.C., Cutri R.M., Nelson B.O. <Astrophys. J. 569, 23 (2002)> =2002ApJ...569...23S
ADC_Keywords: Active gal. nuclei ; QSOs ; Polarization ; Photometry, infrared Keywords: galaxies: active - galaxies: ISM - polarization - quasars: general Abstract: Optical broadband polarimetry is presented for near-infrared color-selected active galactic nuclei (AGNs) classified as quasi-stellar objects (QSOs) based on their Ks-band luminosity. More than 10% of a sample of 70 QSOs discovered in the Two Micron All Sky Survey (2MASS, Cat. <B/2mass>) with J-Ks>2 and MKs←23 show high broadband linear polarization (P>3%), and values range to a maximum of P∼11%. High polarization tends to be associated with the most luminous objects at Ks and with QSOs having the highest near-IR to optical flux ratios. The 2MASS QSO sample includes objects possessing a wide range of optical spectral types. High polarization is seen in two of 22 broad emission-line (type 1) objects, but ∼1/4 of the QSOs of intermediate spectral type (type 1.5-1.9) are highly polarized. None of the nine QSOs classified as type 2 exhibit P>3%. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 104 101 Optical polarimetry of 2MASS Red QSOs table2.dat 103 23 Optical polarimetry of other AGN found by 2MASS table3.dat 79 10 Galactic interstellar polarization detected in the fields of 2MASS AGNs
See also: B/2mass : The 2MASS database (IPAC/UMass, 2000) Byte-by-byte Description of file: table1.dat table2.dat
Bytes Format Units Label Explanations
1- 6 A6 --- --- [2MASSI] 8- 23 A16 --- 2MASSI The 2MASSI object name 25- 29 F5.3 --- z ? Redshift from Cutri et al. (2001, ASP Conf. Ser. 232, 78) 31- 34 A4 --- SpType Spectral classification (1) 36- 40 F5.2 mag Kmag The K_s_ band magnitude (2) 42- 45 F4.2 mag J-Ks The (J-K_s_) color (2) 47 A1 --- l_B-Ks Limit flag on B-K 48- 51 F4.2 mag B-Ks The (B-K_s_) color (2) 53- 58 F6.2 mag KMag ? The absolute Ks band magnitude 60- 63 I4 yr Obs.Y ? UT year of the observation 65- 66 I2 "month" Obs.M ? UT month of the observation 68- 69 I2 d Obs.D ? UT day of the observation 71 A1 --- f_Pol [a] a indicates that the polarization data is an average of the previous observations 73- 77 F5.2 % Pol Degree of linear polarization (3) 79- 82 F4.2 % e_Pol The 1σ error on Polar 84- 88 F5.1 deg theta ? Polarization position angle 90- 93 F4.1 deg e_theta ? The 1σ error on theta 95-103 A9 --- Comm Comments (4)
Note (1): Taken from Cutri et al. (2001, ASP Conf. Ser. 232, 78): L = LINER; S = Starburst; 1.x = objects with broad Hα emission lines, but show no evidence of an Hβ emission line; 1.b = objects that show broad Hα, but the spectra do not extend far enough to the blue to reach Hβ. Note (2): Data are from the 2MASS Point Source Catalog. Note (3): Not corrected for statistical bias. Note (4): Comments: 2H60: Unfiltered observation obtained with the Two-Holer photo-polarimeter using a 4" aperture at the Steward Observatory Mt. Lemmon 1.5 m (60-inch) telescope; 2H90: Unfiltered observation obtained with the Two-Holer instrument using a 2.9" aperture at the Bok (90-inch) telescope; spol: Optical spectropolarimetry of 2MASSI J151653.2+190048 and 2MASSI J165939.7+183436 is reported by Smith et al. (2000ApJ...545L..19S).
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 6 A6 --- --- [2MASSI] 8- 23 A16 --- 2MASSI The 2MASSI object name 25- 37 A13 --- Object The object name 39- 40 I2 h RAh Right ascension (J2000.0) 42- 43 I2 min RAm Right ascension (J2000.0) 45- 48 F4.1 s RAs Right ascension (J2000.0) 50 A1 --- DE- Declination sign (J2000.0) 51- 52 I2 deg DEd Declination (J2000.0) 54- 55 I2 arcmin DEm Declination (J2000.0) 57- 58 I2 arcsec DEs Declination (J2000.0) 60- 63 F4.2 % Pol Polarisation percentage 65- 68 F4.2 % e_Pol rms uncertainty on Pol 70- 74 F5.1 deg theta Polarization angle 76- 79 F4.1 deg e_theta rms uncertainty on theta
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 17-Jun-2002
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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