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J/A+A/466/63        VLBI observations of BL Lac objects         (Wu+, 2007)

VLBI observations of seven BL Lacertae objects from RGB sample. Wu Z., Jiang D.R., Gu M., Liu Y. <Astron. Astrophys., 466, 63-73 (2007)> =2007A&A...466...63W
ADC_Keywords: BL Lac objects ; Radio sources ; Redshifts Keywords: BL Lacertae objects: general - galaxies: active - galaxies: jets - galaxies: nuclei - radio continuum: galaxies Abstract: We present EVN observations of seven BL Lac objects selected from the RGB sample. To investigate the intrinsic radiation property of BL Lac objects, we estimated the Doppler factor with the VLA or MERLIN core and the total 408MHz luminosity for a sample of 170 BL Lac objects. The intrinsic (comoving) synchrotron peak frequency was then calculated by using the estimated Doppler factor. Assuming a Lorentz factor of 5, the viewing angle of jets was constrained. The high-resolution VLBI images of seven sources all show a core-jet structure. We estimated the proper motions of three sources with the VLBI archive data, and find that the apparent speed increases with the distance of components to the core for all of them. Description: All seven BL Lac objects were observed with European VLBI Network (EVN) at 5GHz on 22 November 1999. The raw data were obtained with the MKIII VLBI recording system, with an effective bandwidth of 28MHz, and correlated in Bonn at the Max-Planck-Institute. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 86 170 The sample of 170 BL Lac objects selected from Nieppola et al. (2006, Cat. J/A+A/445/441). refs.dat 70 17 References
See also: J/A+A/445/441 : SED of BL Lacertae objects (Nieppola+, 2006) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 8 A8 --- IAU IAU name (HHMM+DDd) 10- 25 A16 --- Source Source name 27- 31 F5.3 --- z Redshift 32 A1 --- n_z [*] * for unknown redshift and taken as the average redshift of LBL/IBL/HBL subclass 34- 38 F5.2 [Hz] log(nu) Intrinsic synchrotron peak frequency after excluding the Doppler factor, log(nu'peak) 40- 44 F5.2 [W/Hz] logP Total radio power at 408MHz 45 A1 --- n_logP [abcde] Frequency used to derive logP (1) 47- 51 F5.2 [W/Hz] logPc 5GHz core luminosity 53- 58 F6.2 mJy FExt ?=- 5GHz extended flux density 59 A1 --- n_FExt [f] f: extend flux at 1.4GHz 62- 66 A5 --- Refs References for core and extended flux in refs.dat file 68- 71 F4.1 --- delta Doppler factor 73- 76 F4.1 deg theta3 Viewing angle of {GAMMA}=3 78- 81 F4.1 deg theta5 Viewing angle of {GAMMA}=5 83- 86 F4.1 deg theta10 Viewing angle of {GAMMA}=10
Note (1): Note as follows: a = from 408MHz b = from 360MHz c = from extended flux d = from total 1.4GHz e = from 330MHz
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Ref Reference number 4- 22 A19 --- BibCode BibCode 24- 49 A26 --- Aut Author's name 51- 70 A20 --- Com Comments
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Oct-2007
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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