People involved at OAB: Cacciari
RR Lyr is the nearest (i.e. brightest) and the best-studied variable star of its type and therefore plays a crucial role in setting the zero-point of the distance scale. We have obtained the first infrared (JHK) complete light curves for RR Lyr, derived a new estimate of reddening, distance and physical parameters for this star, provided a more reliable and accurate absolute calibration of the period K-luminosity relation and discussed the implications of these new results on the zero-point of the distance scale (Sollima et al. 2008).
This work was done in collaboration with A. Sollima (Univ. of Bologna) and A. Piersimoni (INAF-Teramo Obs.), as well as astronomers from the Pulkovo Observatory and the Sobolev Astronomical Inst. (St. Petersburg, CSI).