Cool Stars 14 - Submitted Abstract # 255
This version created on 05 October 2006

Distance Determination to Mira Variables Using Radial Velocity and
Interferometric Measurements


Lee Rottler, Caltech/IPAC
Gerard Van Belle, Caltech/MSC
David Ciardi, Caltech/MSC
Graeme Smith, Lick Observatory

We have observed a sample of Mira Variables in the optical with the
Hamilton Echelle Spectrograph at Lick Observatory, at selected lines
in the K band with the CSHELL at IRTF, and with the Palomar Testbed
Interferometer (PTI) at Palomar Observatory.  These measurements were
taken over a large fraction of the variability cycle for the stars in
the sample at all 3 observatories.  Although the Lick and IRTF data
were not taken contemporaneously, the PTI measurements were
contemporaneous with all of the spectrographic data taken at these
observatories.  In this work we present the radial velocity curves
derived from the Lick Hamilton Echelle data and correlate them to the
angular size variations derived from the PTI measurements as a
function of phase.  By combining the spectral and interferometric data
taken in the visible and IR it is possible to use a Baade-Wesselink
analysis to determine the distance to each of the stars in our sample.
We present our results using this method and discuss the accuracy of
the distances found.

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