Can stellar winds account for temperature fluctuations in H II regions?

The case of NGC 2363

¹ European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching b. München, Germany
² Instituto de Astronomía, Universidad Nacional Autónoma de México, Ap. Postal 70-264, 04510 México D.F., Mexico
³ Max-Planck-Institut für extraterrestrische Physik, Gießenbachstraße, 85748 Garching b. München, Germany

Corresponding author: V. Luridiana, vale@astroscu.unam.mx

Received: 13 August 2001
Accepted: 25 September 2001

Abstract

We compare the rate of kinetic energy injected by stellar winds into the extragalactic H ii region NGC 2363 to the luminosity needed to feed the observed temperature fluctuations. The kinetic luminosity associated to the winds is estimated by means of two different evolutionary synthesis codes, one of which takes into account the statistical fluctuations expected in the Initial Mass Function. We find that, even in the most favorable conditions considered by our model, such luminosity is much smaller than the luminosity needed to account for the observed temperature fluctuations. The assumptions underlying our study are emphasized as possible sources of uncertainty affecting our results.