[vsnet-alert 832] DV UMa eclipse ephemeris

[Taichi Kato <tkato>]

   I have tried to refine the eclipse ephemeris of DV UMa using the following
available mid-eclipse times.

  HJD-2400000          source
 -----------------------------------------
  46854.7485 Howell et al. (MNRAS 233, 79)
  46854.8339             "
  46854.9195             "
  46855.6944             "
  46855.7798             "
  46855.8660             "
  46855.9517             "
  46856.4646             "
  46856.5503             "
  46856.6370             "
  46857.4963             "
  46857.5815             "
  49775.9696 Nogami et al. (vsnet-alert 56)
  49776.0554             "
  49776.1410             "
  49776.2269             "
  49779.0601             "
  49779.1457             "
  49779.2317             "
  50079.289  Kato (unpublished)

   The best fit ephemeris is

  Min.HJD = 2446854.7487 + 0.085852614 E     (1),

which expresses all the observed times within an error of 0.002 day.

  The second best (viable) solution is

  Min.HJD = 2446854.7483 + 0.085877839 E     (2)

  Using the equation (1), predicted times of eclipses on Apr. 9 and 10
would become:

   YYMMDD hh:mm:ss (UT Geo)
   970409 00:36:14
   970409 02:39:53
   970409 04:43:31
   970409 06:47:09
   970409 08:50:47
   970409 10:54:26
   970409 12:58:04
   970409 15:01:42
   970409 17:05:20
   970409 19:08:59
   970409 21:12:37
   970409 23:16:15

   970410 01:19:53
   970410 03:23:32
   970410 05:27:10
   970410 07:30:48
   970410 09:34:26
   970410 11:38:05
   970410 13:41:43
   970410 15:45:21
   970410 17:48:59
   970410 19:52:38
   970410 21:56:16

  The equation (2) predicts eclipses 1h 18m later.

  Hope this would help, and someone could confirm or reject this prediction.

Regards,
Taichi Kato

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