INVESTIGADORES
CORSICO Alejandro Hugo
artículos
Título:
Constraining the neutrino magnetic dipole moment from white dwarf pulsations
Autor/es:
A. H. CÓRSICO; L. G. ALTHAUS; M. M. MILLER BERTOLAMI; S. O. KEPLER; E. GARCÍA-BERRO
Revista:
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
Editorial:
IOP PUBLISHING LTD
Referencias:
Lugar: Londres; Año: 2014 vol. 8 p. 54 - 73
ISSN:
1475-7516
Resumen:
Pulsating white dwarf stars can be used as astrophysical laboratories to
constrain the properties of weakly interacting particles. Comparing the
cooling rates of these stars with the expected values from theoretical
models allows us to search for additional sources of cooling due to the
emission of axions, neutralinos, or neutrinos with magnetic dipole
moment. In this work, we derive an upper bound to the neutrino magnetic
dipole moment (μν) using an estimate of the rate of
period change of the pulsating DB white dwarf star PG 1351+489. We
employ state-of-the-art evolutionary and pulsational codes which allow
us to perform a detailed asteroseismological period fit based on fully
DB white dwarf evolutionary sequences. Plasmon neutrino emission is the
dominant cooling mechanism for this class of hot pulsating white dwarfs,
and so it is the main contributor to the rate of change of period with
time (Pi dot) for the DBV class. Thus, the inclusion of an anomalous
neutrino emission through a non-vanishing magnetic dipole moment in
these sequences notably influences the evolutionary timescales, and also
the expected pulsational properties of the DBV stars. By comparing the
theoretical Pi dot value with the rate of change of period with time of
PG 1351+489, we assess the possible existence of additional cooling by
neutrinos with magnetic dipole moment. Our models suggest the existence
of some additional cooling in this pulsating DB white dwarf, consistent
with a non-zero magnetic dipole moment with an upper limit of
μν lesssim 10-11 μB. This
bound is somewhat less restrictive than, but still compatible with,
other limits inferred from the white dwarf luminosity function or from
the color-magnitude diagram of the Globular cluster M5. Further
improvements of the measurement of the rate of period change of the
dominant pulsation mode of PG 1351+489 will be necessary to confirm our
bound.