J/ApJ/818/187 The cosmic TeV gamma-ray background spectrum (Inoue+, 2016)
Lower bound on the cosmic TeV gamma-ray background radiation.
Inoue Y., Tanaka Y.T.
<Astrophys. J., 818, 187 (2016)>
=2016ApJ...818..187I 2016ApJ...818..187I (SIMBAD/NED BibCode)
ADC_Keywords: Gamma rays ; Active gal. nuclei
Keywords: cosmic background radiation; gamma rays: diffuse background;
gamma rays: general
Abstract:
The Fermi gamma-ray space telescope has revolutionized our
understanding of the cosmic gamma-ray background radiation in the GeV
band. However, investigation on the cosmic TeV gamma-ray background
radiation still remains sparse. Here, we report the lower bound on the
cosmic TeV gamma-ray background spectrum placed by the cumulative flux
of individual detected extragalactic TeV sources including blazars,
radio galaxies, and starburst galaxies. The current limit on the
cosmic TeV gamma-ray background above 0.1TeV is obtained as
2.8x10-8(E/100GeV)-0.55exp(-E/2100GeV)[GeV/cm2/s/sr]
<E2dN/dE<1.1x10-7(E/100GeV)-0.49[GeV/cm2/s/sr], where the upper
bound is set by requirement that the cascade flux from the cosmic TeV
gamma-ray background radiation can not exceed the measured cosmic GeV
gamma-ray background spectrum. Two nearby blazars, Mrk421 and Mrk501,
explain ∼70% of the cumulative background flux at 0.8-4TeV, while
extreme blazars start to dominate at higher energies. We also provide
the cumulative background flux from each population, i.e., blazars,
radio galaxies, and starburst galaxies which will be the minimum
requirement for their contribution to the cosmic TeV gamma-ray
background radiation.
Description:
We select 35 known extragalactic TeV sources which are located at
Galactic latitude |b|≥10° and whose low activity state flux is
available, since our aim is to give conservative constraints on the
total cosmic gamma-ray background (CGB) in the TeV band.
For each source, we select the lowest fluxes among several TeV
measurements by modern imaging atmospheric Cherenkov telescopes
(IACTs; H.E.S.S., MAGIC, and VERITAS) and further restrict samples
showing no significant variability in the TeV band during
observations. The sample contains 30 blazars, 3 radio galaxies, and 2
starburst galaxies from the default TeVcat catalog (Wakely & Horan
2008ICRC....3.1341W 2008ICRC....3.1341W) which include published sources only.
We also include the Fermi third source (3FGL) catalog data (Acero et
al. 2015, J/ApJS/218/23) to cover GeV gamma-ray spectra. The 3FGL
catalog is based on its first 48 months of survey data. All of our
sample have counterparts in the 3FGL catalog.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 122 35 Extragalactic TeV gamma-ray objects at |b|≥10°
table2.dat 32 16 The lower bound on the cosmic TeV gamma-ray
background spectrum
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See also:
J/ApJS/222/5 : The second Fermi-LAT >50GeV catalog (2FHL) (Ackermann+, 2016)
J/ApJS/218/23 : Fermi LAT third source catalog (3FGL) (Acero+, 2015)
J/ApJ/799/86 : Diffuse gamma-ray emission 0.1-820GeV (Ackermann+, 2015)
J/ApJ/780/73 : Redshifts of BL Lac objects from Fermi (Ajello+, 2014)
J/ApJS/207/16 : BL Lac candidates for TeV observations (Massaro+, 2013)
J/A+A/542/A94 : 1RXSJ101015.9-311909 VHE gamma-ray emission (HESS+, 2012)
J/ApJ/722/520 : Gamma-ray light curves of Fermi blazars (Abdo+, 2010)
J/A+A/410/813 : 2001 Flare of Mkn 421 in gamma-ray (Aharonian+ 2003)
J/A+A/406/L9 : TeV Gamma-Rays from 1ES1959+650 (Aharonian+, 2003)
J/A+A/390/39 : HEGRA AIROBICC gamma radiation above 15 TeV (Aharonian+, 2002)
http://tevcat.uchicago.edu/ : TeVCat online gamma-ray catalog
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- Name Source identifier
23- 28 F6.2 deg RAdeg Right ascension in decimal degrees (J2000)
30- 35 F6.2 deg DEdeg Declination in decimal degrees (J2000)
37- 42 F6.2 deg GLON Galactic longitude
44- 49 F6.2 deg GLAT Galactic latitude
51- 66 A16 --- Class Object classification ("blazar", "radio galaxy"
or "starburst galaxy")
68- 71 A4 --- --- [3FGL]
73- 84 A12 --- 3FGL 3FGL name (JHHMM.m+DDMM)
86-102 A17 --- Auth First author's name of the reference
104-122 A19 --- BibCode Bibcode of the reference
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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- 8 F8.2 GeV Energy [0.2/13000] Energy bin
10- 16 E7.1 GeV/cm2/s/sr Flux Lower bound flux
18- 24 E7.1 GeV/cm2/s/sr e_Flux Lower uncertainty in Flux
26- 32 E7.1 GeV/cm2/s/sr E_Flux Upper uncertainty in Flux
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-May-2016