Does Boo Really Have a Planetary Companion?
W. D. Cochran, A. P. Hatzes (University of Texas)
The claimed detection of photospheric line profile variability in 51 Peg
by Gray (1997) and the resulting controversy over whether the observed
radial velocity variations of that stars are the result of stellar reflex
motion due to a planetary companion or are a manifestation of stellar
pulsation has prompted us to search for similar spectral variability in
Boo. This star shows radial velocity variations with an even smaller
period (3.31 days) and a velocity amplitude (469ms ) eight
times larger than that of 51 Peg. If Boo is also merely
a pulsating star (as Gray claims is true of 51 Peg), then it should
show line profile variations much larger than those seen in 51 Peg.
We used the high resolution (R = 230,000) mode of the 2dcoudé
spectrograph of the McDonald Observatory 2.7m Harlan Smith Telescope
to observe Boo in January, March and May 1997. The results of
the line bisector analysis are presented, and their implications for
the existence of planets in very short period orbits are discussed.