J/A+A/489/849 Revised catalogue of EGRET gamma-ray sources (Casandjian+, 2008)
A revised catalogue of EGRET γ-ray sources.
Casandjian J.-M., Grenier I.A.
<Astron. Astrophys., 489, 849-883 (2008)>
=2008A&A...489..849C 2008A&A...489..849C
ADC_Keywords: Gamma rays ; Surveys
Keywords: catalogs - gamma rays: observations - ISM: structure
Abstract:
We present a catalog of point gamma-ray sources detected by the
EGRET detector on the Compton Gamma Ray Observatory. We used the
entire gamma-ray dataset of reprocessed photons at energies above
100MeV and new Galactic interstellar emission models based on CO, HI,
dark gas, and interstellar radiation field data. Two different
assumptions are used to describe the cosmic-ray distribution in the
Galaxy to analyse the systematic uncertainties in source detection and
characterization.
We applied a 2-dimensional maximum-likelihood detection method similar
to that used to analyze the 3rd EGRET catalogue.
The revised catalogue lists 188 sources, 14 of which are marked as
confused, in contrast to the 271 entries of the 3rd EGRET (3EG)
catalogue. We do not detect 107 sources discovered previously because
additional structure is present in the interstellar background.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 32 46 List of individual or short periods used in the
analysis in addition to the summed cycles
table3.dat 14 104 Names of the 3EG sources with no EGR counterpart
table4.dat 15 27 Names of the new EGR sources with no 3EG counterpart
egr.dat 120 1512 EGR catalogue of 174 sources (tableA1 in the paper)
egrc.dat 135 128 EGR Confused sources catalogue (14 sources)
(tableB1 in the paper)
--------------------------------------------------------------------------------
See also:
J/ApJS/123/79 : Third EGRET catalog (3EG) (Hartman+, 1999)
J/ApJS/135/155 : Radio identification of 3EG EGRET sources (Mattox+, 2001)
J/ApJS/157/324 : EGRET high-energy cosmic photons (E>10GeV) (Thompson+, 2005)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- vp vp designation
9- 32 A24 --- Com Sum of viewing periods
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [3EG]
5- 14 A10 --- 3EG 3EG name (JHHMM+DDMM)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name EGR or EGRc name
--------------------------------------------------------------------------------
Byte-by-byte Description of file: egr.dat egrc.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/174] Sequential number
5- 19 A15 --- Name Name (EGR JHHMM+DDMM or EGRc JHHMM+DDMM)
21- 26 F6.2 deg RAdeg Right ascension in decimal degrees (J2000)
28- 34 F7.2 deg DEdeg Declination in decimal degrees (J2000)
37- 43 F7.2 deg GLON [-360/360] Galactic longitude
45- 50 F6.2 deg GLAT Galactic latitude
52- 55 F4.2 deg r95 θ95, angular radius of a circular
cone that contains the same solid angle
as the 95% confidence contour
57- 61 F5.1 10-4ph/m2/s Flux Flux for E>100MeV and for each time period
(in 10-8ph/cm2/s)
63- 66 F4.1 10-4ph/m2/s e_Flux rms uncertainty on Flux
68- 71 I4 ct Cts Number of photons detected with E>100MeV
73- 77 F5.1 --- TS.5 sqrt(TS), detection significance of the
source at the given position (3)
79- 85 A7 --- vp Short viewing period or summed cycles (1)
87- 93 F7.2 deg GLONsys Galactic longitude obtained with the
Galprop background model
95-100 F6.2 deg GLATsys Galactic latitude obtained with the
Galprop background model
102-106 F5.1 10-4ph/m2/s Fluxsys Flux obtained with the Galprop background
model (in 10-8ph/cm2/s)
108-110 A3 --- --- [3EG]
111-120 A10 --- 3EG 3EG (Cat. J/ApJS/123/79) EGRET catalog
counterpart source name (2)
122-135 A14 --- EGR EGR name for EGRc sources (egrc file only)
--------------------------------------------------------------------------------
Note (1): Short viewing period as defined in table1.dat or summed cycles
noted px for cycle x, pijkl for the sum of cycles i, j, k, and l, and
p19 for the total of 9 cycles (1-9).
Note (2): If one exists within a radius of 1 PSF FWHM (2° for E>100MeV)
from the EGR source and if the nearest neighbour relation between the
EGR and 3EG sources is univocal (the nearest neighbour of the EGR
source is the 3EG one and vice versa).
Note (3): the test statistics used for source detection behaves
asymptotically as a χ2; detections use a threshold of
sqrt(TS)>5 at low latitude (|b|<10°), and sqrt(TS)>4 otherwise.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 18-Oct-2008