Pulsation Time Scales and Amplitudes in a Sample of BrightSemi - Regular Variable

نویسندگان

  • Robert A. Donahue
  • Willie H. Soon
  • Sallie L. Baliunas
  • Gregory W. Henry
چکیده

We have analyzed the diierential V-band photometric variations of records up to 8 years long in ten M III semi-regular variable stars. Periodograms constructed from each star's entire record and seasonal intervals were used to nd repetitive occurrences of pulsation periods in the range of 10 to 250 days. For every star at least one locus of periods was observed, with many stars showing two distinct distributions of pulsation time scales. The observed pulsation periods and diierential V-magnitude semi-amplitudes appear to be correlated such that longer periods correspond to larger semi-amplitudes.

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تاریخ انتشار 2007