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We present calibrations of the effective temperatures of giant stars versus [Fe/H] and colours , , , , , , , , , , and . These calibrations are based on a large sample of field and globular cluster stars which roughly cover spectral types from F0 to K5. Their effective temperatures, scaled to direct determinations via reliable angular diameter measurements, were derived by applying the infrared flux method. The empirical relations have been fitted to polynomials of the form by using the least squares method. The precision of the fits ranges from 40 K for to 170 K for . We tabulate intrinsic colours of giant stars in the ranges: 3500 K 8000 K; -3.0 . We also present the calibration of BC(V) as a function of log and metallicity. Finally, we compare the resulting scale of temperatures with previous works.

We have applied the InfraRed Flux Method (IRFM) to a sample of approximately 500 giant stars in order to derive their effective temperatures with an internal mean accuracy of about 1.5% and a maximum uncertainty in the zero point of the order of 0.9%. For the application of the IRFM, we have used a homogeneous grid of theoretical model atmosphere flux distributions developed by Kurucz (1993). The atmospheric parameters of the stars roughly cover the ranges: 3500 K 8000 K; -3.0 ; 0.5 . The monochromatic infrared fluxes at the continuum are based on recent photometry with errors that satisfy the accuracy requirements of the work. We have derived the bolometric correction of giant stars by using a new calibration which takes the effect of metallicity into account. Direct spectroscopic determinations of metallicity have been adopted where available, although estimates based on photometric calibrations have been considered for some stars lacking spectroscopic ones. The adopted infrared absolute flux calibration, based on direct optical measurements of stellar angular diameters, puts the effective temperatures determined in this work in the same scale as those obtained by direct methods. We have derived up to four temperatures, T J , T H , T K and , for each star using the monochromatic fluxes at different infrared wavelengths in the photometric bands J , H , K and . They show good consistency over 4000 K, and there is no appreciable trend with wavelength, metallicity and/or temperature. We provide a detailed description of the steps followed for the application of the IRFM, as well as the sources of error and their effect on final temperatures. We also provide a comparison of the results with previous work.

We present the results of a three-year campaign of broad-band photometry in the near-infrared J, H, K and L 0 bands for a sample of approximately 250 giant stars carried out at the Observatorio del Teide (Tenerife, Spain). Transformations of the Telescopio Carlos S anchez system into/from several currently used infrared systems are extended to the redward part of the colour axis. The linearity of our photometric system in the range 3m ag (Fe/H) > 3. Data of comparable quality previously published have been added to the sample in order to increase the reliability of the relations to be ob- tained. We also provide mean IR colours for giant stars according to spectral type 1 .

We have applied the InfraRed Flux Method (IRFM) to a sample of 475 dwarfs and subdwarfs in order to derive their eective temperatures with a mean accuracy of about 1.5%. We have used the new homogeneous grid of theoretical model atmosphere flux distributions developed by Kurucz (1991, 1993) for the application of the IRFM. The atmospheric parameters of the stars cover, roughly, the ranges: 3500 K Te 8000 K; 3.5 (Fe/H) +0:5; 3.5 log(g) 5. The monocromatic infrared fluxes at the continuum, and the bolometric fluxes are derived using recent results, which satisfy the accuracy requeriments of the work. Photometric calibrations have been revised and applied to estimate metallicities, although direct spectroscopic determinations were preferred when available. The adopted infrared absolute flux calibration, based on direct optical measurements of angular stellar diameters, sets the eective temperatures determined using the IRFM on the same scale than those obtained by direct methods. We derive three temperatures, TJ , TH and TK , for each star using the monochromatic fluxes at dierent infrared wavelengths in the photometric bands J, H ,a nd K. They show good consistency over 4000 K, and no trend with wavelength may be appreciated. We provide a detailed description of the steps followed for the application of the IRFM, as well as the sources of the errors associated to the dierent inputs of the method, and their transmission into the nal temperatures. We also provide comparison with previous works.