Stars as Laboratories for Fundamental Physics - MPP Theory Group

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Preface
ence of GUT monopoles in the universe have been reviewed, for example,
in the cosmology book of Kolb and Turner (1990). Because nothing
of substance has changed, a new review did not seem warranted.
WIMPs trapped in stars would contribute to the heat transfer because
their mean free path can be so large that they may be orbiting
almost freely in the star’s gravitational potential well, with only
occasional collisions with the background medium. Originally it was
thought that this effect could reduce the central solar temperature
enough to solve the solar neutrino problem, and to better an alleged
discrepancy between observed and predicted solar p-mode frequencies.
With the new solar neutrino data it has become clear, however, that a
reduction of the central temperature alone cannot solve the problem.
Worse, solving the “old solar neutrino problem” by the WIMP mechanism
now seems to cause a discrepancy with the observed solar p-mode
frequencies (Christensen-Dalsgaard 1992). In addition, a significant effect
requires relatively large scattering cross sections and thus rather
contrived particle-physics models. Very restrictive direct laboratory
constraints exist for the presence of these “cosmions” in the galaxy.
Given this status I was not motivated to review the topic in detail.
The annihilation of dark-matter WIMPs captured in the Sun or
Earth produces high-energy neutrinos which are measurable in terrestrial
detectors such as Kamiokande or the future Superkamiokande,
NESTOR, DUMAND, and AMANDA Cherenkov detectors. This indirect
approach to search for dark matter may well turn into a serious
competitor for the new generation of direct laboratory search experiments
that are currently being mounted. This material is extensively
covered in a forthcoming review Supersymmetric Dark Matter by Jungman,
Kamionkowski, and Griest (1995); there is no need for me to
duplicate the effort of these experts.
The topics covered in my book revolve around the impact of lowmass
or massless particles on stars or the direct detection of this radiation.
The highest energies encountered are a few 100 MeV (in the
interior of a SN core) which is extremely small on the high-energy scales
of typical particle accelerator experiments. Therefore, stars as laboratories
for fundamental physics help to push the low-energy frontier of
particle physics and as such complement the efforts of nonaccelerator
particle experiments. Their main thrust is directed at the search for
nonstandard neutrino properties, but there are other fascinating topics
which include the measurement of parity-violating phenomena in
atoms, the search for neutron or electron electric dipole moments which
would violate CP, the search for neutron-antineutron oscillations, the