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J/MNRAS/376/960  X-ray emission from the Sombrero galaxy (NGC 4594)  (Li+, 2007)
Chandra and XMM-Newton detection of large-scale diffuse X-ray emission from the
Sombrero galaxy.
    Li Z., Wang Q.D., Hameed S.
   <Mon. Not. R. Astron. Soc., 376, 960-976 (2007)>
   =2007MNRAS.376..960L
ADC_Keywords: Galaxies, nearby ; X-ray sources

Keywords: galaxies: general - galaxies: individual: Sombrero, NGC 4594 -
          galaxies: spiral - X-rays: general

Abstract:
    We present an X-ray study of the massive edge-on Sa galaxy, Sombrero
    (M 104; NGC 4594), based on XMM-Newton and Chandra observations. A list
    of 62 XMM-Newton and 175 Chandra discrete X-ray sources is provided,
    the majority of which are associated with the galaxy. Spectral
    analysis is carried out for relatively bright individual sources and
    for an accumulated source spectrum.

Description:
    The Chandra ACIS-S observation of Sombrero (Obs. ID. 1586) was taken
    on 2001 May 31 with an exposure of 18.8ks.
    The XMM-Newton EPIC observation of Sombrero (Obs. ID 0084030101) was
    taken on 2001 December 28, with the thin filter and with a total
    exposure of 43ks.

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table2.dat        63      175   Chandra source list
table3.dat        64       62   XMM-Newton source list
table4.dat        49        8   Matching results with 2MASS


See also:
   J/ApJ/599/1067 : X-ray sources in M104 (Di Stefano+, 2003)


Byte-by-byte Description of file: table2.dat

   Bytes Format Units    Label    Explanations

   1-  3  I3    ---    [LWH2007]  [1/175] Source designation,
                                           [LWH2007] Chandra NNN in Simbad
   5- 23  A19   ---      CXOU     CXOU name (JHHMMSS.ss-DDMMSS.s)
  25- 27  F3.1  arcsec   e_Pos    Position uncertainty (1σ) calculated
                                   from the maximum likelihood centroiding
  29- 34  F6.2  ct/ks    CR       On-axis source broad-band count rate (1)
  36- 39  F4.2  ct/ks    e_CR     rms uncertainty on CR
  41- 45  F5.2  ---      HR       ?=- Harness ratio, HR=(H-S2)/(H+S2) (2)
  47- 50  F4.2  ---      e_HR     ?=- rms uncertainty on HR
  52- 56  F5.2  ---      HR1      ?=- Harness ratio 1, HR1=(S2-S1)/S (2)
  58- 61  F4.2  ---      e_HR1    ?=- rms uncertainty on HR1
      63  A1    ---      Band     [BSH] band in which a source is detected with
                                    the most accurate position that is adopted
                                    in Position uncertainty (e_Pos)

Note (1): The sum of the exposure-corrected CRs in the four bands.

Note (2): Definition of the bands:
           S1=0.3-0.7keV, S2=0.7-1.5keV, H1=1.5-3keV and H2=3-7keV.
     In addition, S=S1+S2, H=H1+H2 and B=S+H.
     The hardness ratios defined as HR=(H-S2)/(H+S2), and HR1=(S2-S1)/S,
     listed only for values with uncertainties less than 0.2.


Byte-by-byte Description of file: table3.dat

   Bytes Format Units    Label     Explanations

   1-  3  I3    ---     [LWH2007]  [1/62] Source designation,
                                           [LWH2007] XMM NNN in Simbad
   5- 23  A19   ---      XMMU      XMMU name (JHHMMSS.ss-DDMMSS.s)
  25- 27  F3.1  arcsec   e_Pos     Position uncertainty (1σ) calculated
                                    from the maximum likelihood centroiding
  29- 34  F6.2  ct/ks    CR        On-axis source broad-band count rate (1)
  36- 40  F5.2  ct/ks    e_CR      rms uncertainty on CR
  42- 46  F5.2  ---      HR        ?=- Harness ratio, HR=(H-S2)/(H+S2) (2)
  48- 51  F4.2  ---      e_HR      ?=- rms uncertainty on HR
  53- 57  F5.2  ---      HR1       ?=- Harness ratio1, HR1=(S2-S1)/S (2)
  59- 62  F4.2  ---      e_HR1     ?=- rms uncertainty on HR1
      64  A1    ---      Band      [BSH] band in which a source is detected with
                                    the most accurate position that is adopted
                                    in Position uncertainty (e_Pos)

Note (1): The sum of the exposure-corrected CRs in the four bands.

Note (2): Definition of the bands:
          S1=0.5-1keV, S2=1-2keV, H1=2-4.5keV and H2=4.5-7.5keV.
     In addition, S=S1+S2, H=H1+H2 and B=S+H.
     The hardness ratios defined as HR=(H-S2)/(H+S2), and HR1=(S2-S1)/S,
     listed only for values with uncertainties less than 0.2.


Byte-by-byte Description of file: table4.dat

   Bytes Format Units     Label     Explanations

   1-  2  A2    ---       List      [XA XP] XA for table2, XP for table3
       3  A1    ---       ---       [-]
   4-  6  I3    ---      [LWH2007]  Source designation
   8- 26  A19   ---       Name      Name (JHHMMSS.ss+DDMMSS.s)
  28- 30  F3.1  arcsec    Dox       Distance between X-ray and optical position
  32- 34  F3.1  arcsec    e_Dox     rms uncertainty on Dox
  36- 39  F4.1  mag       Jmag      J magnitude
  41- 44  F4.1  mag       Hmag      H magnitude
  46- 49  F4.1  mag       Kmag      K magnitude


History:
    From electronic version of the journal
(End)                                      Patricia Vannier [CDS]    28-Sep-2007