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 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:
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FileName Lrecl Records Explanations
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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
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See also:
J/A+A/445/441 : SED of BL Lacertae objects (Nieppola+, 2006)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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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
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Note (1): Note as follows:
a = from 408MHz
b = from 360MHz
c = from extended flux
d = from total 1.4GHz
e = from 330MHz
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 49 A26 --- Aut Author's name
51- 70 A20 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Oct-2007