We have used near- and mid-infrared interferometry to investigate the
pulsating atmosphere and the circumstellar environment of the Mira variable RR
Aql. Observations were taken with the VLTI/AMBER (near infrared) and the
VLTI/MIDI (mid infrared) instruments. We have obtained a total of 15 MIDI
epochs between Apr 9, 2004 and Jul 28, 2007 covering 4 pulsation cycles and one
AMBER epoch on Sep 9, 2006 at phase 2.82. This work is also part of an ongoing
project of joint VLTI and VLBA observations to study the connection between
stellar pulsation and the mass loss process. Here we present a comparison of
the AMBER visibility data to a simple uniform disk model as well as to
predictions by recent self-excited dynamic model atmospheres. The best fitting
photospheric angular diameter of the model atmosphere at phase 2.82 is 9.9 +/-
2.4 mas.Comment: 4 pages, 3 figures, to appear in Proc. of Cool Stars 1
