J/MNRAS/327/771 BeppoSAX HELLAS survey. II. (Fiore+, 2001)
The BeppoSAX High Energy Large Area Survey (HELLAS).
II. Number counts and X-ray spectral properties.
Fiore F., Giommi P., Vignali C., Comastri A., Matt G., Perola G.C.,
La Franca F., Molendi S., Tamburelli F., Antonelli L.A.
<Mon. Not. R. Astron. Soc. 327, 771 (2001)>
=2001MNRAS.327..771F 2001MNRAS.327..771F
ADC_Keywords: X-ray sources
Mission_Name: BeppoSAX
Keywords: galaxies: active - X-rays: diffuse background - X-rays: galaxies -
X-rays: general
Abstract:
The BeppoSAX High Energy Large Area Survey (HELLAS) has surveyed about
85deg2 of sky in the 5-10keV band down to a flux of
4-5x10-14erg/cm2/s. The source surface density of 16.9±6.4deg2
at the survey limit corresponds to a resolved fraction of the 5-10keV
X-ray background (XRB) of the order of 20-30 per cent.
Hardness ratio analysis indicates that the spectra of a substantial
fraction of the HELLAS sources (at least one-third) are harder than a
αE=0.6 power law. This hardness may be caused by large
absorbing columns. The hardness ratio analysis also indicates that
many HELLAS sources may have a spectrum more complex than a single
absorbed power law. A soft component, superimposed on a strongly
cut-off power law, is likely to be present in several sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 77 147 HELLAS sample
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See also:
J/A+A/362/799 : The BeppoSAX 2-10 keV Survey (Giommi+, 2000)
J/A+A/370/900 : BeppoSAX HELLAS survey. IV (Vignali+, 2001)
J/ApJ/570/100 : BeppoSAX HELLAS survey. V. (La Franca+, 2002)
J/MNRAS/342/575 : BeppoSAX HELLAS survey. VI. (Ciliegi+, 2003)
J/A+A/409/79 : HELLAS2XMM survey. IV. (Fiore+, 2003)
http://argos.mporzio.astro.it/hellas/ :
The High Energy Large Area Survey (HELLAS) Home Page
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right ascension (J2000)
4- 5 I2 min RAm Right ascension (J2000)
7- 10 F4.1 s RAs Right ascension (J2000)
12 A1 --- DE- Declination sign (J2000)
13- 14 I2 deg DEd Declination (J2000)
16- 17 I2 arcmin DEm Declination (J2000)
19- 20 I2 arcsec DEs Declination (J2000)
22- 25 F4.1 arcmin Offset Off-axis angle
27- 31 F5.2 10-16W/m2 F5-10keV Flux at 5-10keV (in 10-13erg/cm2/s)
33- 36 F4.1 --- S/N Signal to noise ratio
38- 42 F5.2 --- S-H/S+H ? Softness ratio, S-H/S+H (1)
44- 47 F4.2 --- e_S-H/S+H ? rms uncertainty on S-H/S+H
48 A1 --- n_S-H/S+H [b] Note on S-H/S+H (2)
49- 53 F5.2 --- HR1 ? Hardness ratio 1, HR1=(M-L)/(M+L) (1)
55- 58 F4.2 --- e_HR1 ? rms uncertainty HR1
59 A1 --- n_HR1 [bc] Note on HR1 (2)
61- 65 F5.2 --- HR2 ? Hardness ratio 2, HR2=(H-M)/(H+M) (1)
67- 70 F4.2 --- e_HR2 ? rms uncertainty HR2
71 A1 --- n_HR2 [bc] Note on HR2 (2)
73- 77 A5 --- HELLAS Identification number
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Note (1): Bands:
L=1.3-2.5keV
M=2.5-4.5keV
S=1.3-4.5KeV = L+M
H=4.5-10keV
Note (2): Notes:
b: partly obscured by the Medium Energy Concentrator Spectrometer
(MECS) strongback
c: S/N<3.8
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History:
From electronic version of the journal
References:
Fiore et al.. Paper I 1999MNRAS.306L..55F 1999MNRAS.306L..55F
Comastri et al., Paper III 2001MNRAS.327..781C 2001MNRAS.327..781C
Vignali et al., Paper IV 2001A&A...370..900V 2001A&A...370..900V, Cat. J/A+A/370/900
La Franca et al., Paper V 2002ApJ...570..100L 2002ApJ...570..100L, Cat. J/ApJ/570/100
(End) James Marcout, Patricia Bauer [CDS] 30-Jan-2002