CDROM/APJ/V483/P826     Berkeley 17 (Phelps 1997)
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Berkeley 17: The Oldest Open Cluster?
        Randy L. Phelps
        <1997, ApJ, 483, 826>
        =1997ApJ...483..826P
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Abstract:
     Faint magnitude BVI CCD photometry of the central region of the old
  open cluster Berkeley 17 (Be 17) has been undertaken to investigate
  the claim that it is the oldest open cluster yet discovered (Phelps,
  Janes, & Montgomery). This study reveals Be 17 to have a metallicity
  -0.30 <= [Fe/H] <= 0.00; a reddening 0.52 <= E(B-V) <= 0.68 or 0.61 <=
  E(V-I) <= 0.71; a distance modulus, (m-M)0 = 12.15 +/- 0.10,
  corresponding to a distance of 2.7 +/- 0.1 kpc; a diameter of ~10 pc;
  a minimum mass of 400 Msun; and an age of 10-13 Gyr.  With an adopted
  age of 12(+1)(-2) Gyr, these results suggest that Be 17 is indeed the
  oldest open cluster yet discovered. The inferred old age for Be 17
  indicates that the cluster is an important one for studies of the
  differences between open and globular clusters, the transition from
  the halo/thick disk to the thin disk of the Galaxy, and even for
  establishing the minimum age of the universe.

Keywords:  Hertzsprung-Russell diagram -- open clusters and associations:
  individual (Berkeley 17) -- stars: abundances -- stars: evolution


File Summary:
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File Name     Lrecl     Records     Explanations
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fig1a.dat       51        619       V,B-V color-magnitude diagram data for Be 17
fig1b.dat       51        797       V,V-I color-magnitude diagram data for Be 17
fig2.dat        51        448       V,V-I color magnitude diagram data for
                                    the Be 17 off-cluster control field
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Byte-by-byte Description of file: fig1a.dat
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   Bytes Format  Units       Label      Explanations
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   1- 3   I3     ---         ID         Identification number
   4-12   F9.2   pix         X          X coordinate
  13-21   F9.2   pix         Y          Y coordinate
  22-29   F8.3   mag         V          V magnitude
  30-37   F8.3   mag         B-V        B-V color
  38-44   F7.3   mag         e_V        Error in V
  45-51   F7.3   mag         e_B-V      Error in B-V
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Byte-by-byte Description of file: fig1b.dat fig2.dat
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   Bytes Format  Units       Label      Explanations
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   1- 3   I3     ---         ID         Identification number
   4-12   F9.2   pix         X          X coordinate
  13-21   F9.2   pix         Y          Y coordinate
  22-29   F8.3   mag         V          V magnitude
  30-37   F8.3   mag         V-I        V-I color
  38-44   F7.3   mag         e_V        Error in V
  45-51   F7.3   mag         e_V-I      Error in V-I
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(End)                                            Lee E. Brotzman [ADS] 24-Jul-97