J/AJ/148/42 S4 0954+658 outburst in 2011 March-April (Morozova+, 2014)
The outburst of the blazar S4 0954+658 in 2011 March-April.
Morozova D.A., Larionov V.M., Troitsky I.S., Jorstad S.G., Marscher A.P.,
Gomez J.L., Blinov D.A., Efimova N.V., Hagen-Thorn V.A., Hagen-Thorn E.I.,
Joshi M., Konstantinova T.S., Kopatskaya E.N., Larionova L.V.,
Larionova E.G., Lahteenmaki A., Tammi J., Rastorgueva-Foi E., McHardy I.,
Tornikoski M., Agudo I., Casadio C., Molina S.N., Volvach A.E.,
Volvach L.N.
<Astron. J., 148, 42 (2014)>
=2014AJ....148...42M 2014AJ....148...42M
ADC_Keywords: BL Lac objects ; Polarization ; Photometry, RI
Keywords: BL Lacertae objects: individual: S4 0954+658 - galaxies: active -
galaxies: jets - polarization
Abstract:
We present the results of optical (R-band) photometric and
polarimetric monitoring and Very Long Baseline Array imaging of the
blazar S4 0954+658, along with Fermi γ-ray data during a
multi-waveband outburst in 2011 March-April. After a faint state with
a brightness level R∼17.6mag registered in the first half of 2011
January, the optical brightness of the source started to rise and
reached ∼14.8mag during the middle of March, showing flare-like
behavior. The most spectacular case of intranight variability was
observed during the night of 2011 March 9, when the blazar brightened
by ∼0.7mag within 7hr. During the rise of the flux, the position
angle of the optical polarization rotated smoothly over more than
300°. At the same time, within 1σ uncertainty, a new
superluminal knot appeared with an apparent speed of 19.0±0.3c. We
have very strong evidence that this knot is associated with the
multi-waveband outburst in 2011 March-April. We also analyze the
multi-frequency behavior of S4 0954+658 during a number of minor
outbursts from 2008 August to 2012 April. We find some evidence of
connections between at least two additional superluminal ejecta and
near-simultaneous optical flares.
Description:
We carry out optical BVRI observations at the 70cm AZT-8 reflector of
the Crimean Astrophysical Observatory, and 40cm LX-200 telescope in
St. Petersburg, Russia. The telescopes are equipped with identical
photometers-polarimeters based on ST-7 CCDs. We perform observations
in photometric and polarimetric modes at the 1.8m Perkins telescope of
Lowell Observatory (Flagstaff, AZ) using the PRISM camera and at the
2.2m telescope of the Calar Alto Observatory (Almeria, Spain) within
the MAPCAT program
(http://www.iaa.es/~iagudo/research/MAPCAT/MAPCAT.html). Photometric
measurements in R band are supplemented by observations at the 2m
Liverpool Telescope at La Palma, Canary Islands, Spain. Polarimetric
observations at the AZT-8, Perkins, and Calar Alto telescopes are
carried out in the Cousins R band, while at the LX-200 telescope they
are performed in white light, with effective wavelength close to R
band.
The BL Lac object S4 0954+658 is monitored monthly by the Boston
University (BU) group with the Very Long Baseline Array (VLBA) at
43GHz within a sample of bright γ-ray blazars
(http://www.bu.edu/blazars). We have constructed total and polarized
images at 33 epochs from 2010 August to 2012 April. During this
period, we have identified 12 components, A1, K1, K2, K3, K4, K5, K6,
K7, K8, K9, K10, K11, in addition to the core, A0.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
09 58 47.25 +65 33 54.8 S4 0954+658 = QSO B0954+658
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 55 157 Photometry and polarimetry of S4 0954+658
during 2011 April-May outburst
table2.dat 40 89 Polarization properties of knots on Very Long
Baseline Array (VLBA) images
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See also:
J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
J/ApJ/672/40 : AO 0235+164 outburst in 2006 December (Hagen-Thorn+, 2008)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d RJD Reduced Julian Date of observation (JD-2400000)
12- 17 F6.3 mag Rmag [14.8/17.2] The R band magnitude
19- 23 F5.3 mag e_Rmag The 1σ error in Rmag
25- 29 F5.2 % Pol [1.7/28.9] The R band intrinsic polarization level
31- 34 F4.2 % e_Pol The 1σ error in RPol
36- 40 F5.1 deg polPA The R band Electric Vector Position Angle
42- 45 F4.1 deg e_polPA The 1σ error in polPA
47- 55 A9 --- Tel Telescope (AZT-8+ST7, CAHA, LX-200, or Perkins) (1)
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Note (1): Telescope code is:
AZT-8+ST7 = The 70cm AZT-8 reflector of the Crimean Astrophysical Observatory;
CAHA = The 2.2m telescope of the Calar Alto Observatory (Almeria, Spain);
LX-200 = The 40cm LX-200 telescope in St. Petersburg, Russia;
Perkins = The 1.8m Perkins telescope of Lowell Observatory (Flagstaff, AZ).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 F7.1 d MJD Modified Julian Date of observation
(JD-2400000.5)
9- 12 A4 --- Name The component name (CORE, K2-9) (1)
14- 17 F4.2 Jy Flux [0.02/1.13] The 43GHz flux density
19- 22 F4.1 % Pol The 43GHz intrinsic polarization level
24- 28 F5.1 deg polPA ? The 43GHz Electric Vector Position Angle (2)
30- 40 A11 "D:M:Y" ObsDate Date of observation epoch at 43GHz
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Note (1): We have constructed total and polarized images at 33 epochs from
2010 August to 2012 April. During this period, we have identified 12
components, A1, K1, K2, K3, K4, K5, K6, K7, K8, K9, K10, K11, in
addition to the core, A0. The core is a stationary feature located at
the southern end of the portion of the jet that is visible at 43GHz.
Note (2): A blank indicates an unknown polPA value.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 24-Nov-2014