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\centerline{\ft ON THE NEW VARIABLE $\lambda$ BOOTIS STAR HD\,109738}
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We present new spectroscopic and photometric observations for 
the $\lambda$ Bootis star
HD 109738. Photometric observations were made during the night of 03/04 May 1995
at CTIO,
Chile with the Lowell-telescope. The
integration time was 30 seconds in Str\"omgren $b$ and $v$. HD\,111480 (V=8.3,
A3V)
was used as a comparison star and proved to be constant within an upper limit
of 3 mmag in Str\"omgren $b$. 

$\lambda$ Bootis stars are a group of metal poor, Population I, A-type
stars. Their evolutionary status is not well known (Paunzen et al. 1995b).
HD\,109738 was found by Hauck (1986) as a photometric $\lambda$ Bootis star
candidate in the Geneva system. Recent spectroscopic
observations with the 1.6 meter 
telescope at Itajuba, Brazil,  
confirm the membership of the $\lambda$ Bootis group.


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Figure 1. The lightcurve for HD\,109738 and HD\,111480 in 
instrumental Str\"omgren $b$
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The photometric observations were made during a survey to detect variability 
in a sample of $\lambda$ Bootis stars (Paunzen et al., 1995a). 
The aim of this survey is to establish pulsation in these stars.
For HD\,109738 we found a period
of about 47 minutes with an amplitude of 18 mmag in 
Str\"omgren $b$.
Since the dataset covers only about 3 hours, the given values are
preliminary.  
From hitherto 25 photometrically investigated $\lambda$ Bootis stars, 13 proved
to be variable (Paunzen et al., 1995b). The observed periods range from 30 minutes
to 4 hours.  

{\it Acknowledgements}: This research was done within the working group
{\em Asteroseismology-AMS}. Computing resources and financial support
for this international collaboration were provided by the Fonds zur 
F\"orderung der wissenschaftlichen Forschung (project {\em P 8776
-PHY}) and
the Hochschuljubil\"aumsstiftung der Stadt Wien ($\lambda$ Bootis
Sterne). We acknowledge receipt of telescope time at CTIO and Itajuba.  
This research has made use of the Simbad database, operated at CDS, Strasbourg,
France.

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\beginauthors
\authorsrightcol
E. PAUNZEN
Institut f\"ur Astronomie,
T\"urkenschanzstra\ss e 17,
A-1180 Wien, Austria
e-mail: 
paunzen@astro.ast.univie.ac.at                       %email
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\references

Hauck, B., 1986, {\it A\&A}, {\bf 154}, 349 

Paunzen, E., Weiss, W.W., North, P., 1995a, {\it IBVS}, No.\,4068 

Paunzen, E., Weiss, W.W., Heiter, U., North, P., 1995b, {\it A\&A}, submitted 
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