J/ApJS/248/8 9-yr of Fermi-LAT & Swift obs. of 3C 454.3 flares (Das+, 2020)
Gamma-Ray Flares in the Long-term Light Curve of 3C 454.3.
Das A.K., Prince R., Gupta N.
<Astrophys. J. Suppl. Ser., 248, 8 (2020)>
=2020ApJS..248....8D 2020ApJS..248....8D
ADC_Keywords: QSOs; Gamma rays; Active gal. nuclei
Keywords: Galactic and extragalactic astronomy; Extragalactic astronomy;
Quasars; Active galactic nuclei; Blazars; Jets
Abstract:
3C 454.3 is frequently observed in the flaring state. The long-term
light curve of this source has been analyzed with 9yr (2008 August -
2017 July) of data from the Fermi-LAT detector. We have identified
five flares and one quiescent state. The flares have substructures
with many peaks during the flaring phase. We have estimated the rise
and decay time of the flares and compared with flares of other similar
sources. The modeling of gamma-ray spectral energy distributions shows
in most cases that a log-parabola function gives the best fit to the
data. We have done time-dependent leptonic modeling of two of the
flares, for which simultaneous multiwavelength data are available.
These two long-lasting flares, Flare-2A and Flare-2D, continued for 95
and 133 days, respectively. We have used the average values of Doppler
factor, injected luminosity in electrons, size of the emission region,
and the magnetic field in the emission region in modeling these
flares. The emission region is assumed to be in the broad-line region
in our single-zone model. The energy losses (synchrotron, synchrotron
self-Compton, external Compton) and escape of electrons from the
emission region have been included while doing the modeling. Although
the total jet powers required to model these flares with the leptonic
model are higher compared to other sources, they are always found to
be lower than the Eddington luminosity of 3C 454.3. We also select
some flaring peaks and show that the time variation of the Doppler
factor or the injected luminosity in electrons over short timescales
can explain their light curves.
Description:
We have extracted the Fermi/LAT data of the blazar 3C 454.3 source
from the Fermi Science Support Center (FSSC)'s website data server
over a period of 9yr (2008 August-2017 July).
We also have analyzed the archival data from the Swift-XRT/UVOT for
the source 3C 454.3 during the time period of 2009-2011 April (∼2yr),
which have been retrieved from the HEASARC website.
The source 3C 454.3 was also observed by the Swift Ultraviolet/Optical
Telescope (UVOT) in all six filters: U, V, B, W1, M2, and W2.
Objects:
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RA (ICRS) DE Designation(s) (Redshift)
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22 53 57.75 +16 08 53.6 3C 454.3 = LEDA 281932 (z∼0.859)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 46 69 Rising and Decay time for given peak time
and peak flux which is calculated by temporal
fitting of the light curves with the sum of an
exponential function
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See also:
B/swift : Swift Master Catalog (HEASARC, 2004-)
J/A+A/436/799 : X- & gamma-ray fluxes of γ-ray-loud blazars (Fan+, 2005)
J/A+A/450/39 : BVRI photometry of 8 red blazars (Gu+, 2006)
J/AJ/134/799 : Multiwaveband polarimetry of 15 AGN (Jorstad+, 2007)
J/ApJ/712/405 : Multiwavelength obs. of 3C 454.3 III. (Vercellone+, 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/ApJ/763/L36 : MgII and FeII flux of the blazar 3C 454.3 (Leon-Tavares+, 2013)
J/ApJS/218/23 : Fermi LAT third source catalog (3FGL) (Acero+, 2015)
J/ApJS/223/15 : 8yr INTEGRAL/IBIS soft gamma-ray source obs. (Bird+, 2016)
J/ApJS/224/26 : SEDs of Roma BZCAT blazars (Mao+, 2016)
J/ApJ/833/77 : gamma-ray bright blazars optical polarization (Itoh+, 2016)
J/ApJ/851/33 : Multi-wavelength analysis of CGRaBS blazars (Paliya+, 2017)
J/ApJ/856/80 : 6-yr optical monitoring of the FSRQ 3C 454.3 (Fan+, 2018)
J/ApJ/866/137 : Bright blazars variability brightness temp. (Liodakis+, 2018)
J/A+A/609/A68 : Full-Stokes polarimetry of 5 radio sources (Myserlis+, 2018)
J/A+A/626/A60 : F-GAMMA 2.64-43GHz radio data over 2007-2015 (Angelakis+, 2019)
J/ApJS/247/33 : The Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)
http://fermi.gsfc.nasa.gov/cgi-bin/ssc/LAT/LATDataQuery.cgi : Fermi/LAT data
http://heasarc.gsfc.nasa.gov/ : HEASARC home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Flare Flare identifier code (1)
3- 9 F7.1 d t0 [54719.1/57743.4] Modified Julian Date
of peak time
11- 15 F5.2 10-6ph/cm2/s F0 [3.31/80.41] Peak flux
17- 20 F4.2 10-6ph/cm2/s e_F0 [0.28/5.92] Uncertainty in F0
22- 27 F6.2 h Tr [2.83/114.94] Rising time
29- 33 F5.2 h e_Tr [0.78/16.77] Uncertainty in Tr
35- 40 F6.2 h Td [3.16/100.13] Decay time
42- 46 F5.2 h e_Td [0.58/17.67] Uncertainty in Td
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Note (1): Flare code as follows:
a = Flare-1A with 1 day binning;
b = Flare-2A with 1 day binning;
c = 1st part of Flare-2B with 6 hour binning;
d = 1st part of Flare-2B with 6 hour binning;
e = Flare-I of Flare-2C with 6 hour binning;
f = Flare-II of Flare-2C with 6 hour binning;
g = Flare-I of Flare-2D with 6 hour binning;
h = Flare-II of Flare-2D with 6 hour binning;
i = Flare-I of Flare-3A with 6 hour binning;
j = Flare-II of Flare-3A with 6 hour binning;
k = Flare-3B with 6 hour binning;
l = Flare-4A with 6 hour binning;
m = Flare-4B with 6 hour binning;
n = Flare-4C with 6 hour binning;
o = Flare-4D with 6 hour binning;
p = Flare-5A with 6 hour binning;
q = Flare-5B with 6 hour binning;
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 16-Jul-2020