White dwarfs as physics laboratories: the case of axions

White dwarfs are almost completely degenerate objects that cannot obtain energy from thermonuclear sources, so their evolution is just a gravothermal cooling process. Recent improvements in the accuracy and precision of the luminosity function and in pulsational data of variable white dwarfs suggest that they are cooling faster than expected from conventional theory. In this contribution we show that the inclusion of an additional cooling term due to axions able to interact with electrons with a coupling constant g_ae ~(2-7)x10^{-13} allows to fit better the observations.
Comment: 4 pages, 1 figure. Proceedings for the 7th Patras Workshop on Axions, WIMPs and WISPs (PATRAS 2011), Mykonos, Greece, June 27 - July 1, 2011