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J/A+A/356/L21       BR photometry of ON 231                  (Belokon+, 2000)
ON 231: the testing of 3.8-year period for optical outbursts
with multi-peak structure.
     Belokon E.T., Babadzhanyants M.K., Pollock J.T.
    <Astron. Astrophys. 356, L21 (2000)>
    =2000A&A...356..L21B
ADC_Keywords: BL Lac objects ; Photometry, CCD

Keywords: galaxies: BL Lacertae objects: general -
          galaxies: BL Lacertae objects: individual: ON 231

Abstract:
    We present R- and B-band CCD observations of ON 231 that were made at
    the Dark Sky Observatory at Appalachian State University (DSO-data)
    during 37 nights in April 1998 - December 1999. The observations have
    been obtained in connection with current microvariability studies but
    this paper presents only the nightly averaged R and B magnitudes
    together with other details of these observations. These data were
    used to verify the 1395-day period proposed from the analysis of the
    prior data (all B-band data available in the 1971-1997 time interval).
    To transform R-band observations to B we used the equation:
    B=1.107*R-0.653.
Objects:
    ----------------------------------------------------
       RA   (2000)   DE     Designation(s)
    ----------------------------------------------------
    12 21 31.7   +28 13 59  ON 231 = W Com = B2 1219+28
    ----------------------------------------------------

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table1.dat        72       56   R- and B-band photometry of ON 231 (DSO-data)


See also:
 J/A+AS/127/445 : Gamma-ray loud blazars optical monitoring. II. (Raiteri+ 1998)
 J/A+AS/130/109 :  BV(RI)c photometry of ON 231 (Tosti+ 1998)


Byte-by-byte Description of file: table1.dat

   Bytes Format Units   Label     Explanations

   1- 12  F12.4 d       HJDst     [2450928/2451515] Starting Julian date (1)
  15- 26  F12.4 d       HJDend    [2450928/2451515] Ending Julian date (1)
      29  A1    ---     Band      [BR] Standard Johnson spectral band
  32- 37  F6.3  mag     magmax    Maximum of the brightness (2)
  40- 45  F6.3  mag     magmin    Minimum of the brightness (2)
  48- 50  I3    ---     o_mag     Number of measurements (3)
  53- 57  F5.3  mag     e_mag     rms uncertainty on the object magnitude
  60- 64  F5.3  mag     rmsche    rms uncertainty on the check star magnitude
  67- 72  F6.3  mag     mag       Average object magnitude during the
                                    observational run

Note (1): Heliocentric Julian date at the start and end of the observational run
           on this night
Note (2): Brightest and faintest apparent magnitude during the observational run
           on this night
Note (3): Number of individual brightness measurements during the observational
          run


Acknowledgements: Elena Belokon 

(End)                                        Patricia Bauer [CDS]    04-Apr-2000