J/A+A/529/A162 Optically selected BL Lac candidates polarimetry (Heidt+, 2011)
Polarimetry of optically selected BL Lac candidates from the SDSS.
Heidt J., Nilsson K.
<Astron. Astrophys. 529, A162 (2011)>
=2011A&A...529A.162H 2011A&A...529A.162H
ADC_Keywords: Active gal. nuclei ; BL Lac objects ; Polarization
Keywords: polarization - techniques: polarimetric -
BL Lacertae objects: general - galaxies: active
Description:
195 polarimetric measurements of 182 BL Lac candidates from the SDSS
taken with 3 different telescopes are presented. For each candidate
the J2000 coordinates, its redshift, whether a source is listed in
NED, the SDSS r-mag, the telescope for the observations used, the date
of the observations, the exposure time for an individual exposure per
position angle, the measured degree of polarization, the position
angle and references to previous measurements of the sources are
given. 13 objects have been observed twice. Here no entry for the
coordinates is given. The redshifts, NED-listing and SDSS r-mags have
been taken from Collinge et al. (2005, Cat. J/AJ/129/2542).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 86 195 195 polarimetric measurements of 182
BL Lac candidates
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See also:
J/AJ/129/2542 : BL Lac from SDSS (Collinge+, 2005)
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right ascension (J2000.0)
3- 4 I2 min RAm Right ascension (J2000.0)
5- 9 F5.2 s RAs Right ascension (J2000.0)
10 A1 --- DE- Declination sign (J2000.0)
11- 12 I2 deg DEd Declination (J2000.0)
13- 14 I2 arcmin DEm Declination (J2000.0)
15- 18 F4.1 arcsec DEs Declination (J2000.0)
20 A1 --- l_z Limit flag for redshift
21- 26 F6.4 --- z ? Redshift
27 A1 --- u_z [?] Uncertainty flag for redshift
29 A1 --- NED [Y] Listed in NED
31- 35 F5.2 mag rmag ? SDSS r magnitude
37- 39 A3 --- Tel Telescope used (1)
41- 50 A10 "YYYY-MM-DD" Date Date of observation
52- 55 I4 s t.exp Exposure time per position angle
57 A1 --- l_Pol Upper limit for polarization
58- 62 F5.2 % Pol Polarization degree in percent
64- 67 F4.2 % e_Pol ? Error for polarization degree
69- 73 F5.1 deg PA ? Polarization angle
75- 77 F3.1 deg e_PA ? Error for polarization angle
79- 86 A8 --- Prev Previous observations (2)
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Note (1): Telescope code as follows:
NTT = ESO-NTT, La Silla, Chile
CA = Calar Alto 2.2m telescope, Spain
NOT = Nordic Optical Telescope, La Palma, Spain.
Note (2): Previous observations code as follows:
S07 = Smith et al. (2007ApJ...663..118S 2007ApJ...663..118S)
P10b = Plotkin et al. (2010ApJ...721..562P 2010ApJ...721..562P)
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Acknowledgements:
Jochen Heidt, jheidt(at)lsw.uni-heidelberg.de
(End) J. Heidt [ZAH, Heidelberg, Germany], P. Vannier [CDS] 17-Mar-2011