J/A+A/618/A22 Fermi-LAT sources below 100MeV catalog (Principe+, 2018)
The first catalog of Fermi-LAT sources below 100 MeV.
Principe G., Malyshev D., Ballet J., Funk S.
<Astron. Astrophys. 618, A22 (2018)>
=2018A&A...618A..22P 2018A&A...618A..22P (SIMBAD/NED BibCode)
ADC_Keywords: Gamma rays ; Surveys
Keywords: catalogs - surveys - gamma rays: general
Abstract:
We present the first Fermi Large Area Telescope (LAT) low energy
catalog (1FLE) of sources detected in the energy range 30-100MeV.
The imaging Compton telescope (COMPTEL) onboard NASA's Compton
Gamma-Ray Observatory detected sources below 30MeV, while catalogs
of point sources released by the Fermi-LAT and EGRET collaborations
use energies above 100MeV. Because the Fermi LAT detects gamma rays
with energies as low as 20MeV, we create a list of sources detected
in the energy range between 30 and 100MeV, which closes a gap of
point source analysis between the COMPTEL catalog and the Fermi-LAT
catalogs. One of the main challenges in the analysis of point sources
is the construction of the background diffuse emission model. In our
analysis, we use a background-independent method to search for
point-like sources based on a wavelet transform implemented in the
PGWave code. The 1FLE contains 198 sources detected above 3σ
significance with eight years and nine months of the Fermi-LAT data.
For 187 sources in the 1FLE catalog we have found an association in
the Fermi-LAT 3FGL catalog: 148 are extragalactic, 22 are Galactic,
and 17 are unclassified in the 3FGL. The ratio of the number of flat
spectrum radio quasars (FSRQ) to BL Lacertae (BL Lacs) in 1FLE is
three to one, which can be compared with an approximately 1 to 1 ratio
for the 3FGL or a one to six ratio for 3FHL. The higher ratio of the
FSRQs in the 1FLE is expected due to generally softer spectra of
FSRQs relative to BL Lacs. Most BL Lacs in 1FLE are of low-synchrotron
peaked blazar type (18 out of 31), which have softer spectra and
higher redshifts than BL Lacs on average. Correspondingly, we find
that the average redshift of the BL Lacs in 1FLE is higher than in
3FGL or 3FHL. There are 11 sources that do not have associations in
the 3FGL. Most of the unassociated sources either come from regions of
bright diffuse emission or have several known 3FGL sources in the
vicinity, which can lead to source confusion. The remaining
unassociated sources have significance less than 4σ.
Description:
Fermi-LAT - 8.7 years of data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 257 198 Fermi Large Area Telescope (LAT) low energy
catalog (1FLE) of sources detected in the
energy range 30-100MeV
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See also:
J/ApJ/715/429 : First Fermi-LAT AGN catalog (1LAC) (Abdo+, 2010)
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
J/ApJS/218/23 : Fermi LAT third source catalog (3FGL) (Acero+, 2015)
J/A+AS/143/145 : First COMPTEL source catalogue (Schoenfelder+, 2000)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Official source name 1FLE JHHMM+DDMM
(Source_Name)
17- 26 F10.6 deg RAdeg Right Ascension (J2000) (RAJ2000)
28- 37 F10.6 deg DEdeg Declination (J2000) (DEJ2000)
39- 48 F10.6 deg GLON Galactic Longitude (GLON)
50- 59 F10.6 deg GLAT Galactic Latitude (GLAT)
61- 68 F8.6 deg ePos Error radius at 95% confidence
(Conf95Radius)
70- 76 F7.3 --- Signi Source significance in sigma units over the
30MeV to 100MeV band (Signif_Avg)
78- 89 E12.6 mW/m2 EF30-100 Energy flux (nuFnu) from 30MeV to 100MeV
(EnergyFlux30100)
91-102 E12.6 mW/m2 e_EF30-100 1 sigma error on energy flux (nuFnu) from
30MeV to 100MeV (UncEnergyFlux30_100)
104-115 E12.6 mW/m2 EF100-300 Energy flux (nuFnu) from 100 to 300 MeV
(EnergyFlux100300)
117-128 E12.6 mW/m2 e_EF100-300 1 sigma error on energy flux (nuFnu) from
100MeV to 300MeV (UncEnergyFlux100_300)
130-141 E12.6 1/cm2/s F30-100 Photon flux from 30MeV to 100MeV
(Flux30_100)
143-154 E12.6 1/cm2/s e_F30-100 1 sigma error on photon flux from 30MeV to
100MeV (UncFlux30100)
156-167 E12.6 1/cm2/s F100-300 Photon flux from 100 to 300MeV
(Flux100_300)
169-180 E12.6 1/cm2/s e_F100-300 1 sigma error on photon flux from 100MeV
to 300MeV (UncFlux100300)
182-186 A5 --- Class1 Class designation for the associated source
in the 3FGL catalog, J/ApJS/218/23 (CLASS1)
188-195 F8.6 --- z Redshift for the associated source in the
3LAC catalog, J/ApJS/218/23 (Redshift)
197-214 A18 --- Assoc1 Name of identified or likely associated
sources in the 3FGL catalog, J/ApJS/218/23
(ASSOC1)
216-233 A18 --- Assoc3FGL Associated source in the 3FGL catalog,
J/ApJS/218/23 (ASSOC_3FGL)
235-257 A23 --- AssocCOMP Associated source in the first COMPTEL
catalog, J/A+AS/143/145 (ASSOC_COMPTEL)
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Acknowledgements:
Giacomo Principe, giacomo.principe91(at)gmail.com
(End) Patricia Vannier [CDS] 22-Jun-2018