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J/other/BASI/29.519     VI CCD photometry in NGC 6631             (Sagar+, 2001)
A deep VI CCD photometric study of the neglected galactic star cluster NGC 6631.
    Sagar R., Naidu B.N., Mohan V.
   <Bull. Astron. Soc. India, 29, 519 (2001)>
   =2001BASI...29..519S
ADC_Keywords: Associations, stellar ; Photometry, CCD

Keywords: photometry - cluster: NGC 6631 - colour-magnitude diagram


Abstract:
    We present VI CCD photometric observations of about 5500 stars up to a
    limiting magnitude of V∼20 in an area of ∼16'x16' around the cluster
    NGC 6631. The cluster parameters determined for the first time by
    fitting the theoretical isochrones in the V, (V-I) diagram of the
    cluster stars are E(V-I)=0.60±0.05mag, distance=2.6±0.5kpc,
    age=400±100Myr and metallicity, Z=0.05. The cluster diameter
    determined from the radial density profile is 4.8±0.5pc. The mass
    function of the cluster has a slope of 2.1±05.

Description:
    The VI CCD photometric observations were obtained during May 8 to 10,
    2001.
Objects:
    ----------------------------------------------------------
       RA   (2000)   DE       Designation(s)
    ----------------------------------------------------------
    18 27 12      -12 02.0    NGC 6631
    ----------------------------------------------------------

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table.dat         40     5533   VI-Cousins CCD observations


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

   Bytes Format Units   Label     Explanations

   1-  4  I4    ---     SNM       Sequential number, Cl* NGC 6631 SNM NNNN in Simbad
   7- 14  F8.2  pix     Xpos      X position (1)
  17- 24  F8.2  pix     Ypos      Y position (1)
  29- 33  F5.2  mag     Vmag      Johnson V magnitude
  37- 40  F4.2  mag     V-Ic      Johnson-Cousins V-Ic colour index

Note (1): North is up and East is left. 1pix =0.48".



History:
    Copied at http://obswww.unige.ch//webda/cgi-bin/frame_type_list.cgi?ngc6631
(End)                                        Patricia Bauer [CDS]    07-Nov-2003