J/AJ/126/2740    X-ray emission of RASS Abell clusters       (Ledlow+, 2003)
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The X-ray properties of nearby Abell clusters from the ROSAT All-Sky Survey:
the sample and correlations with optical properties.
    Ledlow M.J., Voges W., Owen F.N., Burns J.O.
   <Astron. J., 126, 2740-2751 (2003)>
   =2003AJ....126.2740L
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ADC_Keywords: Surveys ; Clusters, galaxy ; X-ray sources
Keywords: catalogs - galaxies: clusters: general - surveys - X-rays

Abstract:
    We present an analysis of the X-ray emission for a complete sample of
    288 Abell clusters spanning the redshift range 0.016<=z<=0.09 from the
    ROSAT All-Sky Survey. This sample is based on our 20cm VLA survey of
    nearby Abell clusters. We find an X-ray detection rate of 83%. We
    report cluster X-ray fluxes and luminosities and two different flux
    ratios indicative of the concentration and extent of the emission. We
    examine correlations between the X-ray luminosity, Abell richness, and
    Bautz-Morgan and Rood-Sastry cluster morphologies. We find a strong
    correlation between LX and cluster richness coupled with a dependence
    on the optical morphological type. These results are consistent with
    the observed scatter between X-ray luminosity and temperature and a
    large fraction of cooling flows. For each cluster field, we also
    report the positions, peak X-ray fluxes, and flux ratios of all X-ray
    peaks above 3{sigma} significance within a box of 2x2(h_75_)^-1^Mpc
    centered on Abell's position.

File Summary:
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 FileName   Lrecl  Records   Explanations
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ReadMe         80        .   This file
table1.dat     86      579   X-ray Properties of Nearby Abell Cluster Sample
table2.dat     57      856   X-ray Peaks and Optical identifications
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See also:
    IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)

Byte-by-byte Description of file: table1.dat
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   Bytes Format Units      Label   Explanations
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   1-  5  A5    ---        Abell   Abell cluster identification
       7  A1    ---      f_Abell   [*4] Flag on Abell (1)
   9- 14  F6.4  ---        z       Redshift
  16- 19  I4    ---        Exp     Mean RASS exposure time
  21- 22  I2    h          RAh     Hour of Right Ascension (J2000)
  24- 25  I2    min        RAm     Minute of Right Ascension (J2000)
  27- 30  F4.1  s          RAs     Second of Right Ascension (J2000)
      32  A1    ---        DE-     Sign of the Declination (J2000)
  33- 34  I2    deg        DEd     Degree of Declination (J2000)
  36- 37  I2    arcmin     DEm     Arcminute of Declination (J2000)
  39- 40  I2    arcsec     DEs     Arcsecond of Declination (J2000)
  42- 44  I3    kpc        Off     ? Offset X-ray peak projected distance
                                     from Abell's position (2)
      46  A1    ---      l_FX      Limit flag on FX
  47- 51  F5.2 10-15W/m2   FX      ? Peak X-ray flux (10^-12^erg/s/cm^2^)
                                     within a 500(h_75_)^-1^kpc aperture
  53- 56  F4.2 10-15W/m2 e_FX      ? Error in FX
      58  A1    ---      l_LX      Limit flag on LX
  59- 63  F5.2  10+36W     LX      Luminosity in units of 10^43^erg/s (3)
  65- 68  F4.2  10+36W   e_LX      ? Error in LX
  70- 73  F4.1  ---        F500    ? The 500/62.5(h_75_)^-1^kpc aperture
                                     flux ratio
  75- 79  F5.1  ---        S/N     ? Signal to noise (4)
  81- 85  F5.1  ---        S/Nmax  ? Maximum signal to noise
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Note (1): Note on Name
      * = There is a pointed ROSAT PSPC observation
          (including serendipidous) <=0.3{deg} of Abell's position
      4 = A2122 and A2124 form a bimodal cluster-pair at the same redshift
Note (2): A Null value indicates that the position, LX, e_LX, and S/N 
     are for the entire cluster. 
     Offsets indicate the other values are for the X-ray peak.
Note (3): Within a 500(h_75_)^-1^kpc and assuming H_0_=75 and q_0_=0.5.
     When Off = Null, this is the total cluster luminosity centered on
     Abell's position.
Note (4): When Off is blank, this is the total S/N within the aperture.
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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-  5  A5    ---         Abell   Abell cluster identification
   7-  8  I2    h           RAh     Hour of Right Ascension (J2000)
  10- 11  I2    min         RAm     Minute of Right Ascension (J2000)
  13- 16  F4.1  s           RAs     Second of Right Ascension (J2000)
      18  A1    ---         DE-     Sign of the Declination (J2000)
  19- 20  I2    deg         DEd     Degree of Declination (J2000)
  22- 23  I2    arcmin      DEm     Arcminute of Declination (J2000)
  25- 26  I2    arcsec      DEs     Arcsecond of Declination (J2000)
  28- 31  I4    arcsec      Off     X-ray peak projected distance from
                                     Abell's position
  33- 37  F5.2 10-4ct/s/pix PFlux   Peak flux in units of 10^-4^counts/s/pixel
  39- 42  F4.1  ---         F250    The 250/62.5(1/h_75_)kpc aperture flux ratio
  44- 48  F5.1  ---         S/N     Significance of the detection
  50- 55  A6    ---         Note    Cluster emission code (1)
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Note (1): Cluster emission code:
      C = identified the peak with the cluster emission;
      M = cluster emission appears bimodal or multimodal.
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History:
    From electronic version of the journal
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(End)                  Greg Schwarz [AAS], Patricia Vannier [CDS]    12-Jan-2004
