Determination of Miras temperatures from TiO and VO bands. Estimates of distances.

Effective temperatures are determined for a sam- ple of 165 oxygen-rich Miras using indices related to mole- cular band strength of titanium oxide and vanadium oxide com- puted from narrow-band photometry observations. We nd a clearalthoughveryscatteredperiod{temperaturerelationwhich agrees with a previous one. Using a theoretical evolutionary track on AGB and assuming that the scatter around the period{ temperature relation is due to mass differences, we can obtain a period{luminosity relation similar to the one observed in the LMC if the mass range is 0.8 to 2.6 M. Effects of metallicity arediscussed.Thedeterminedluminositiesareusedtocalibrate distances that are compared to several other estimations.