摘要：Context. With the existing and upcoming large multifibre low-resolution spectrographs, the question arises of how precise stellar parameters such as Teff and [Fe/H] can be obtained from low-resolution K-band spectra with respect to traditional photometric temperature measurements. Until now, most of the effective temperatures in Galactic bulge studies come directly from photometric techniques. Uncertainties in interstellar reddening and in the assumed extinction law could lead to large systematic errors (>200 K).
Aims. We obtain and calibrate the relation between Teff and the 12CO first overtone bands for M giants in the Galactic bulge covering a wide range in metallicity.
Methods. We used low-resolution spectra for 20 M giants with well-studied parameters from photometric measurements covering the temperature range 3200
关键词：stars: fundamental parameters;stars: late-type;Galaxy: bulge;infrared: stars
