Physical Parameters in Circumnuclear Star Forming Regions

HÄGELE, G. F.; CARDACI, M. V.; DÍAZ, A. I.; TERLEVICH, E.; TERLEVICH, R.; CASTELLANOS, M.

Cariló

Congreso; Massive Stars: Fundamental Parameters and Circumstellar Interactions; 2006

Facultad de Ciencias Astronómicas y Geofísicas de la Universidad Nacional de La Plata

We present a spectrophotometric study of circumnuclear star forming regions (CNSFRs) in the spiral galaxies: NGC 2903, NGC 3351 and NGC 3504, all of them of over solar metallicity according to standard empirical calibrations. The low excitation of the regions, as evidenced by the weakness of the [OIII] 5007 Å line, precludes the detection and measurement of the auroral [OIII] 4363 Å necessary for the derivation of the electron temperature. It is therefore impossible to obtain a direct determination of the oxygen abundances. Empirical calibrations have to be used instead.