J/MNRAS/430/2464 The CLASS BL Lac sample (Marcha+, 2013)
The CLASS BL Lac sample: the radio luminosity function.
Marcha M.J.M., Caccianiga A.
<Mon. Not. R. Astron. Soc., 430, 2464-2475 (2013)>
=2013MNRAS.430.2464M 2013MNRAS.430.2464M
ADC_Keywords: Radio sources ; BL Lac objects ; Redshifts
Keywords: galaxies: active; BL Lacertae objects: general
galaxies: luminosity function, mass function
Abstract:
This paper presents a new sample of BL Lac objects selected from a
deep (30mJy) radio survey of flat spectrum radio sources (the CLASS
blazar survey). The sample is one of the largest well-defined samples
in the low-power regime with a total of 130 sources of which 55
satisfy the 'classical' optical BL Lac selection criteria, and the
rest have indistinguishable radio properties. The primary goal of this
study is to establish the radio luminosity function (RLF) on firm
statistical ground at low radio luminosities where previous samples
have not been able to investigate. The gain of taking a peek at lower
powers is the possibility to search for the flattening of the
luminosity function which is a feature predicted by the beaming model
but which has remained elusive to observational confirmation. In this
study, we extend for the first time the BL Lac RLF down to very low
radio powers ∼1022W/Hz, i.e. two orders of magnitude below the RLF
currently available in the literature. In the process, we confirm the
importance of adopting a broader, and more physically meaningful set
of classification criteria to avoid the systematic missing of
low-luminosity BL Lacs. Thanks to the good statistics we confirm the
existence of weak but significant positive cosmological evolution for
the BL Lac population, and we detect, for the first time the
flattening of the RLF at L∼1025W/Hz in agreement with the
predictions of the beaming model.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 71 130 Table containing the sources used in this work
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See also:
VIII/40 : GB6 catalog of radio sources (Gregory+ 1996)
VIII/72 : CLASS survey of radio sources (Myers+, 2003)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [GB6]
4- 17 A14 --- GB6 GB6 name (JHHMMSS+DDMMSS)
19- 20 I2 h RAh Right ascension (J2000)
22- 23 I2 min RAm Right ascension (J2000)
25- 29 F5.2 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 41 F4.1 arcsec DEs Declination (J2000)
43- 47 F5.3 --- z [0/1.4]?=- Redshift
49- 52 I4 mJy S5GHz [30/2122] Radio flux at 5GHz
54- 57 F4.1 mag Rmag R-band magnitude
59- 63 F5.2 --- alpha Radio spectral index, α4.81.4
65- 71 A7 --- Class Classifications (1)
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Note (1): Classifications are:
bl = "classical" BL Lac
t0 = type 0 (similar to weak-line AGN when the 400nm break is <20%)
w = weak-line AGN
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 11-Apr-2014