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eliot's picture
Last seen: 1 week 2 days ago
Joined: 08/03/2014 - 14:29

A few months back I created a site to predict binary star eclipses -

Reusing the same code I have created another.  This time for pulsating stars -  Whilst it is up and working I still have a few minor issues to resolve (mostly website copy).

However I am having a struggle interpreting the GCVS catalog data for pulsating stars:

  • I am assuming that the epoch and period combination predicted the minima for eclipsing binary stars, and the maxima for pulsating stars.
  • M-m/D field is a percentage of the period that the eclipse occurs for binaries (manly EB types).  What does it represent for pulsating stars - I would have assumed this is a continuous process and would look more or less sinusoidal, but there are pulsating stars with a value in this field e.g. YZ Boo and TW Her.
Robin Leadbeater's picture
Last seen: 19 hours 44 min ago
Joined: 05/03/2014 - 00:50
saw tooth

These types of star have have distinctly sawtooth pulsations with the rise time shorter than the fall. eg YZ Boo has a catalogued rise time of 31% which seems to tally with the actual light curve

EDIT:from the catalogue field descriptions

This parameter contains either the rise time (M-m) for intrinsic variables, or the duration of the eclipse (D) for eclipsing binaries, both given as a percentage of the period value for the star. These values help to define the shape of the light curve.