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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
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:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table2.dat        77      147   HELLAS sample


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

   Bytes Format Units    Label     Explanations

   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

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


History:
    From electronic version of the journal

References:
     Fiore et al..     Paper I         1999MNRAS.306L..55F
     Comastri et al.,  Paper III       2001MNRAS.327..781C
     Vignali et al.,   Paper IV        2001A&A...370..900V, Cat. J/A+A/370/900
     La Franca et al., Paper V         2002ApJ...570..100L, Cat. J/ApJ/570/100
(End)                         James Marcout, Patricia Bauer [CDS]    30-Jan-2002