J/ApJS/222/6 4.5yr obs. of Mrk421 with ARGO-YBJ & Fermi (Bartoli+, 2016)
4.5 years of multi-wavelength observations of Mrk 421 during the ARGO-YBJ and
Fermi common operation time.
Bartoli B., Bernardini P., Bi X.J., Cao Z., Catalanotti S., Chen S.Z.,
Chen T.L., Cui S.W., Dai B.Z., D'Amone A., Danzengluobu, De Mitri I.,
D'Ettorre Piazzoli B., Di Girolamo T., Di Sciascio G., Feng C.F., Feng Z.,
Feng Z., Gou Q.B., Guo Y.Q., He H.H., Hu H., Hu H., Iacovacci M., Iuppa R.,
Jia H.Y., Labaciren, Li H.J., Liu C., Liu J., Liu M.Y., Lu H., Ma L.L.,
Ma X.H., Mancarella G., Mari S.M., Marsella G., Mastroianni S., Montini P.,
Ning C.C., Perrone L., Pistilli P., Salvini P., Santonico R., Shen P.R.,
Sheng X.D., Shi F., Surdo A., Tan Y.H., Vallania P., Vernetto S.,
Vigorito C., Wang H., Wu C.Y., Wu H.R., Xue L., Yang Q.Y., Yang X.C.,
Yao Z.G., Yuan A.F., Zha M., Zhang H.M., Zhang L., Zhang X.Y., Zhang Y.,
Zhao J., Zhaxiciren, Zhaxisangzhu, Zhou X.X., Zhu F.R., Zhu Q.Q.,
(the ARGO-YBJ Collaboration)
<Astrophys. J. Suppl. Ser., 222, 6 (2016)>
=2016ApJS..222....6B 2016ApJS..222....6B (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Gamma rays ; Radio sources ; X-ray sources ;
Ultraviolet
Keywords: BL Lacertae objects: individual: Markarian 421;
galaxies: active; gamma-rays: general;
radiation mechanisms: non-thermal
Abstract:
We report on the extensive multi-wavelength observations of the blazar
Markarian 421 (Mrk 421) covering radio to γ-rays, during the
4.5yr period of ARGO-YBJ and Fermi common operation time, from 2008
August to 2013 February. These long-term observations, extending over
an energy range of 18 orders of magnitude, provide a unique chance to
study the variable emission of Mrk 421. In particular, due to the
ARGO-YBJ and Fermi data, the entire energy range from 100MeV to 10TeV
is covered without any gap. In the observation period, Mrk 421 showed
both low- and high-activity states at all wavebands. The correlations
among flux variations in different wavebands were analyzed. The X-ray
flux is clearly correlated with the TeV γ-ray flux, while the
GeV γ-rays only show a partial correlation with the TeV
γ-rays. Radio and UV fluxes seem to be weakly or not correlated
with the X-ray and γ-ray fluxes. Seven large flares, including
five X-ray flares and two GeV γ-ray flares with variable
durations (3-58d), and one X-ray outburst phase were identified and
used to investigate the variation of the spectral energy distribution
with respect to a relative quiescent phase. During the outburst phase
and the seven flaring episodes, the peak energy in X-rays is observed
to increase from sub-keV to a few keV. The TeV γ-ray flux
increases up to 0.9-7.2 times the flux of the Crab Nebula. The
behavior of GeV γ-rays is found to vary depending on the flare,
a feature that leads us to classify flares into three groups according
to the GeV flux variation. Finally, the one-zone synchrotron
self-Compton model was adopted to describe the emission spectra. Two
out of three groups can be satisfactorily described using injected
electrons with a power-law spectral index around 2.2, as expected from
relativistic diffuse shock acceleration, whereas the remaining group
requires a harder injected spectrum. The underlying physical
mechanisms responsible for different groups may be related to the
acceleration process or to the environment properties.
Description:
In this paper, we report on the 4.5 year multi-wavelength
data recorded from 2008 August to 2013 February, a period that
includes several large flares of Mrk 421.
The Astrophysical Radiation with Ground-based Observatory at
YangBaJing (ARGO-YBJ) is an extensive air showers (EAS) detector
located at the Yangbajing Cosmic Ray Laboratory in Tibet, P.R. China
(0.3-10TeV).
Fermi-LAT (energy range above 100MeV) began taking science data in
2008 August. The data used in this work have been downloaded through
the Fermi science support center.
To obtain the Swift/BAT (14-195keV) SED, we downloaded all the
available data of Mrk 421 through the HEASARC data archive.
The MAXI Gas Slit Camera (GSC) detector, operating in the 2-20keV
range, began taking data in 2009 August. The light curves for specific
sources are publicly available.
The RXTE-ASM data in the 2-12keV range are publicly available.
The Swift X-ray Telescope (XRT) is a focusing X-ray telescope with an
energy range from 0.2 to 10keV. Swift-UVOT observations of Mrk 421, at
the three ultraviolet bands (UVW1, UVM2, and UVW2) are also available
at the HEASARC data archive.
The OVRO is a 40m radio telescope working at 15.0GHz with 3GHz
bandwidth. The light curve for Mrk 421 is publicly available.
Objects:
--------------------------------------------------------
RA (ICRS) DE Designation(s)
--------------------------------------------------------
11 04 27.31 +38 12 31.8 Mrk421 = 2FGL J1104.4+3812
--------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 63 2235 Light curves shown in Figure 2
table5.dat 54 2965 Energy and flux of the spectral points shown
in Figure 7 and Figure 8
--------------------------------------------------------------------------------
See also:
VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)
J/A+A/578/A22 : Mrk421 in March 2010 (Aleksic+, 2015)
J/A+A/576/A126 : The 2009 multiwavelength campaign on Mrk421 (Aleksic+, 2015)
J/AJ/149/32 : Integrated radio continuum spectra of galaxies (Marvil+, 2015)
J/A+A/562/A64 : Fermi detection of BL Lac objects (Wu+, 2014)
J/ApJS/212/15 : Polarized NVSS sources SEDs (Farnes+, 2014)
J/AJ/147/143 : MOJAVE. XI. Spectral distributions (Hovatta+, 2014)
J/other/RAA/14.1135 : Doppler factor for a Fermi blazar sample (Fan+, 2014)
J/ApJS/207/16 : BL Lac candidates for TeV observations (Massaro+, 2013)
J/A+A/559/A75 : 43GHz observation of the blazar Mrk 421 (Blasi+, 2013)
J/ApJS/209/14 : The Swift/BAT hard X-ray transient monitor (Krimm+, 2013)
J/ApJS/199/31 : Fermi LAT second source catalog (2FGL) (Nolan+, 2012)
J/ApJS/199/8 : Interstellar column densities compilation (Gudennavar+, 2012)
J/A+A/545/A117 : Monitoring of Mrk 421 at 15 and 24 GHz (Lico+, 2012)
J/A+A/541/A160 : Planck + X/γ observations of blazars (Giommi+, 2012)
J/ApJ/761/125 : X and γ spectral indexes of Fermi blazars (Fan+, 2012)
J/ApJ/754/23 : Blazar submm to γ-ray luminosities (Leon-Tavares+, 2012)
J/ApJ/744/177 : VLBA 5GHz observations of Fermi/LAT AGNs (Linford+, 2012)
J/ApJ/741/30 : Radio/γ-ray correlation in AGN (Ackermann+, 2011)
J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)
J/ApJS/186/378 : Hard X-ray survey from Swift-BAT 2004-2006 (Tueller+, 2010)
J/ApJ/722/520 : Gamma-ray light curves of Fermi blazars (Abdo+, 2010)
J/ApJ/716/30 : SED of Fermi bright blazars (Abdo+, 2010)
J/AJ/137/5022 : Variability of radio-bright BL Lac objects (Nieppola+, 2009)
J/ApJ/673/96 : BAT X-ray Survey - III (Ajello+, 2008)
J/AJ/133/1947 : 37GHz observations of BL Lac objects (Nieppola+, 2007)
J/other/APh/26.282 : AGN neutrino source candidates (Achterberg+, 2006)
J/A+A/410/813 : 2001 Flare of Mkn 421 in gamma-ray (Aharonian+ 2003)
J/A+A/390/39 : HEGRA AIROBICC gamma radiation above 15 TeV (Aharonian+, 2002)
J/ApJS/140/143 : HST FOS spectral atlas (Bechtold+, 2002)
J/A+AS/109/267 : Radio to X-Ray distribution of BL Lac Objects (Giommi+, 1995)
http://tevcat.uchicago.edu/ : TeVCat online catalog
http://fermi.gsfc.nasa.gov/ssc : The Fermi Science Support Center
http://swift.gsfc.nasa.gov/ : Swift home page
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 F12.6 d MJD [54686.5/56329.5] Modified Julian Date;
JD-2400000.5
14- 22 F9.6 d Dt [0/15] Delta Time
24- 33 E10.3 --- Flux Flux in detector units (1)
35- 43 E9.3 --- DFlux Delta Flux in detector units (1)
45- 52 A8 --- x_Flux Units for Flux, DFlux (1)
54- 63 A10 --- Det Detector used (1)
--------------------------------------------------------------------------------
Note (1): The units of the Flux and Delta Flux values depend upon the
following detector:
ARGO-YBJ = ct/d (284 measures) ; events.day-1
Fermi-LAT = ph/cm2/s ; photons.cm-2.s-1
Swift-BAT = ph/cm2/s ; photons.cm-2.s-1
MAXI-GSC = ph/cm2/s ; photons.cm-2.s-1
RXTE-ASM = ph/cm2/s ; photons.s-1
Swift-XRT = ph/s (388 measures) ; photons.s-1
Swift-UVOT = mJy (496 measures)
OVRO = Jy (360 measures)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- State Activity State for Mrk 421 (1)
4- 12 E9.3 TeV E [0/5.5] Photon energy
14- 23 E10.3 mW/m2 Flux Flux, E2*dN/dE, erg/cm2/s
25- 33 E9.3 mW/m2 DFlux Delta Flux, δE2*dN/dE, erg/cm2/s
35- 43 E9.3 mW/m2 95ul 95% Flux upper limit, erg/cm2/s
45- 54 A10 --- Det Detector used (same detectors as in table 1)
--------------------------------------------------------------------------------
Note (1): Activity State for Mrk 421 as follows (see table 3):
---------------------------------------------------------------
State MJD F14-195keV F>1TeV
(x10-3) (Icrab=1.85x10-11)
---------------------------------------------------------------
F1 = Flare 1 55144-55149 23.1 2.6 3.2 0.9
F2 = Flare 2 55242-55245 19.2 1.9 7.2 1.5
F3 = Flare 3 55245-55272 12.9 0.9 1.4 0.5
F4 = Flare 4 55475-55503 5.82 0.83 1.9 0.5
F5 = Flare 5 55811-55818 13.3 1.4 2.1 0.8
F6 = Flare 6 56117-56130 1.45 0.40 1.7 0.6
F7 = Flare 7 56130-56187 1.53 0.36 1.1 0.4
OB = Outburst 55000-55350 c 4.58 0.59 0.91 0.14
S1 = Steady 1 54683-55000 2.51 0.16 2.64 0.27
S3 = Steady 2 55516-56106 d 0.318 0.087 0.33 0.10
---------------------------------------------------------------
c = The periods of Flares 1, 2, and 3 have been excluded.
d = The periods of MJD 55801-55831, including Flare 5, have been excluded.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Feb-2016