J/ApJS/232/7 8yr R-band photopolarimetric data of blazar Mrk 421 (Fraija+, 2017)
Long-term optical polarization variability and multiwavelength analysis of
blazar Mrk 421.
Fraija N., Benitez E., Hiriart D., Sorcia M., Lopez J.M., Mujica R.,
Cabrera J.I., De Diego J.A., Rojas-Luis M., Salazar-Vazquez F.A.,
Galvan-Gamez A.
<Astrophys. J. Suppl. Ser., 232, 7-7 (2017)>
=2017ApJS..232....7F 2017ApJS..232....7F (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Photometry, RI ; Polarization
Keywords: acceleration of particles; radiation mechanisms: non-thermal;
BL Lacertae objects: individual: Markarian 421;
galaxies: photometry; gamma rays: general; polarization
Abstract:
The results of 8yr R-band photopolarimetric data of blazar Mrk 421
collected from 2008 February to 2016 May are presented, along with
extensive multiwavelength observations covering radio to TeV
γ-rays around the flares observed in 2008 May, 2010 March, and
2013 April. The most important results are found in 2013, when the
source displayed in the R band a very high brightness state of
11.29±0.03mag (93.60±1.53mJy) on April 10 and a polarization
degree of 11.00%±0.44% on May 13. The analysis of the optical data
shows that the polarization variability is due to the superposition of
two polarized components that might be produced in two distinct
emitting regions. An intranight photopolarimetric variability study
carried out over seven nights after the 2013 April maximum found flux
and polarization variations on the nights of April 14, 15, 16, and 19.
In addition, the flux shows a minimum variability timescale of
Δt=2.34±0.12hr, and the polarization degree presents
variations of∼1%-2% on a timescale of Δt∼minutes. Also, a
detailed analysis of the intranight data shows a coherence length of
the large-scale magnetic field of lB∼0.3pc, which is the same order
of magnitude as the distance traveled by the relativistic shocks. This
result suggests that there is a connection between the intranight
polarimetric variations and spatial changes of the magnetic field.
Analysis of the complete R-band data along with the historical optical
light curve found for this object shows that Mrk 421 varies with a
period of 16.26±1.78yr.
Description:
The optical R-band observations were performed with the 0.84m f/15
Ritchey-Chretien telescope at the Observatorio Astronomico Nacional of
San Pedro Martir (OAN-SPM) in Baja California, Mexico, and with the
instrument POLIMA, a single-beam polarimeter. The R-band
photopolarimetric observations of the BL Lac Mrk 421 were carried out
from 2008 February to 2016 May (see table 1). The total data collected
during 8yr were 385 points obtained in 30 observing runs.
Objects:
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RA (ICRS) DE Designation(s)
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11 04 27.31 +38 12 31.8 Mrk 421 = UGC 6132
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 55 385 R-band photopolarimetric data of Mrk 421
from February 2008 to May 2016
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See also:
J/A+AS/116/403 : VRI photometry of stars in 12 BL Lac objects (Fiorucci+, 1996)
J/A+AS/132/305 : Extragal. radio sources at 22, 37 and 87GHz (Terasranta+ 1998)
J/ApJ/672/40 : AO 0235+164 outburst in 2006 December (Hagen-Thorn+, 2008)
J/ApJ/700/597 : FERMI LAT detected blazars (Abdo+, 2009)
J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)
J/ApJ/794/54 : Polarization and photometry for blazar W Comae (Sorcia+, 2014)
J/A+A/576/A126 : The 2009 multiwavelength campaign on Mrk421 (Aleksic+, 2015)
J/A+A/578/A22 : Mrk421 in March 2010 (Aleksic+, 2015)
J/A+A/593/A91 : Mrk 421 multi-wavelength variability, 2007-2009 (Ahnen+, 2016)
J/ApJS/222/6 : 4.5yr obs. of Mrk421 with ARGO-YBJ & Fermi (Bartoli+, 2016)
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 MJD Modified Julian Date of observation;
JD-2400000.5
12- 16 F5.2 % Pol [0.3/11] Polarization degree
18- 21 F4.2 % e_Pol [0.1/0.5] Uncertainty in Pol
23- 27 F5.1 deg PA Position angle
29- 31 F3.1 deg e_PA [0.8/9] Uncertainty in PA
33- 37 F5.2 mag Rmag [11.2/13.6] R band magnitude
39- 42 F4.2 mag e_Rmag [0.03/0.1] Uncertainty in Rmag
44- 49 F6.3 mJy RFlux [11/94] Optical Flux, R band
51- 55 F5.3 mJy e_RFlux [0.8/4] Uncertainty in RFlux
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 29-Sep-2017