Letter to the Editor

Asteroseismology of Procyon A with SARG at TNG^*

¹ INAF – Oss. Astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy e-mail: [claudi;desidera;gratton]@pd.astro.it
² INAF – Oss. Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy e-mail: [abo;rve;rco]@ct.astro.it
³ Dipartimento di Fisica ed Astronomia, Università di Catania, via S. Sofia 78, 95123 Catania, Italy e-mail: leccia@na.astro.it;lpaterno@ct.astro.it
⁴ McDonald Observatory, The university of Texas at Austin, Austin, TX 78712, USA e-mail: mike@astro.as.texas.edu

Received: 1 October 2004
Accepted: 17 November 2004

Abstract

We present high precision radial velocity measurements on the F5 IV star α CMi obtained by the SARG spectrograph at TNG (Telescopio Nazionale Galileo) exploiting the iodine cell technique. The time series of about 950 spectra of Procyon A taken during 6 observation nights are affected by an individual error of . Thanks to the iodine cell technique, the spectrograph contribution to the Doppler shift measurement error is quite negligible and our error is dominated by the photon statistics [CITE]. An excess of power between 0.5 and 1.5 mHz, detected also by [CITE] has been found. We determined a large separation frequency , consistent with both theoretical estimates [CITE] and previous observations [CITE].