14 research outputs found
The Indirect Search for Dark Matter with IceCube
We revisit the prospects for IceCube and similar kilometer-scale telescopes
to detect neutrinos produced by the annihilation of weakly interacting massive
dark matter particles (WIMPs) in the Sun. We emphasize that the astrophysics of
the problem is understood; models can be observed or, alternatively, ruled out.
In searching for a WIMP with spin-independent interactions with ordinary
matter, IceCube is only competitive with direct detection experiments if the
WIMP mass is sufficiently large. For spin-dependent interactions IceCube
already has improved the best limits on spin-dependent WIMP cross sections by
two orders of magnitude. This is largely due to the fact that models with
significant spin-dependent couplings to protons are the least constrained and,
at the same time, the most promising because of the efficient capture of WIMPs
in the Sun. We identify models where dark matter particles are beyond the reach
of any planned direct detection experiments while being within reach of
neutrino telescopes. In summary, we find that, even when contemplating recent
direct detection results, neutrino telescopes have the opportunity to play an
important as well as complementary role in the search for particle dark matter.Comment: 17 pages, 10 figures, published in the New Journal of Physics 11
105019 http://www.iop.org/EJ/abstract/1367-2630/11/10/105019, new version
submitted to correct Abstract in origina
Determining Supersymmetric Parameters With Dark Matter Experiments
In this article, we explore the ability of direct and indirect dark matter
experiments to not only detect neutralino dark matter, but to constrain and
measure the parameters of supersymmetry. In particular, we explore the
relationship between the phenomenological quantities relevant to dark matter
experiments, such as the neutralino annihilation and elastic scattering cross
sections, and the underlying characteristics of the supersymmetric model, such
as the values of mu (and the composition of the lightest neutralino), m_A and
tan beta. We explore a broad range of supersymmetric models and then focus on a
smaller set of benchmark models. We find that by combining astrophysical
observations with collider measurements, mu can often be constrained far more
tightly than it can be from LHC data alone. In models in the A-funnel region of
parameter space, we find that dark matter experiments can potentially determine
m_A to roughly +/-100 GeV, even when heavy neutral MSSM Higgs bosons (A, H_1)
cannot be observed at the LHC. The information provided by astrophysical
experiments is often highly complementary to the information most easily
ascertained at colliders.Comment: 46 pages, 76 figure
Probing Neutralino Resonance Annihilation via Indirect Detection of Dark Matter
The lightest neutralino of R-parity conserving supersymmetric models serves
as a compelling candidate to account for the presence of cold dark matter in
the universe. In the minimal supergravity (mSUGRA) model, a relic density can
be found in accord with recent WMAP data for large values of the parameter
, where neutralino annihilation in the early universe occurs via the
broad s-channel resonance of the pseudoscalar Higgs boson . We map out rates
for indirect detection of neutralinos via 1. detection of neutrinos arising
from neutralino annihilation in the core of the earth or sun and 2. detection
of gamma rays, antiprotons and positrons arising from neutralino annihilation
in the galactic halo. If indeed -resonance annihilation is the main sink for
neutralinos in the early universe, then signals may occur in the gamma ray,
antiproton and positron channels, while a signal in the neutrino channel would
likely be absent. This is in contrast to the hyperbolic branch/focus point
(HB/FP) region where {\it all} indirect detection signals are likely to occur,
and also in contrast to the stau co-annihilation region, where {\it none} of
the indirect signals are likely to occur.Comment: 12 pages including 4 eps figure
Dark Matter in the MSSM
We have recently examined a large number of points in the parameter space of
the phenomenological MSSM, the 19-dimensional parameter space of the
CP-conserving MSSM with Minimal Flavor Violation. We determined whether each of
these points satisfied existing experimental and theoretical constraints. This
analysis provides insight into general features of the MSSM without reference
to a particular SUSY breaking scenario or any other assumptions at the GUT
scale. This study opens up new possibilities for SUSY phenomenology both in
colliders and in astrophysical experiments. Here we shall discuss the
implications of this analysis relevant to the study of dark matter.Comment: 27 pages, 19 figs; Journal version in NJP issue "Focus on Dark Matter
and Particle Physics". Previous version had 26 pages, 19 figures. Text and
some figures have been update
Mass Bounds on a Very Light Neutralino
Within the Minimal Supersymmetric Standard Model (MSSM) we systematically
investigate the bounds on the mass of the lightest neutralino. We allow for
non-universal gaugino masses and thus even consider massless neutralinos, while
assuming in general that R-parity is conserved. Our main focus are laboratory
constraints. We consider collider data, precision observables, and also rare
meson decays to very light neutralinos. We then discuss the astrophysical and
cosmological implications. We find that a massless neutralino is allowed by all
existing experimental data and astrophysical and cosmological observations.Comment: 36 pages, 13 figures, minor modification in astro-physical bounds.
EPJC versio
Collider, direct and indirect detection of supersymmetric dark matter
We present an overview of supersymmetry searches, both at collider
experiments and via searches for dark matter (DM). We focus on three DM
possibilities in the SUSY context: the thermally produced neutralino, a mixture
of axion and axino, and the gravitino, and compare and contrast signals that
may be expected at colliders, in direct detection (DD) experiments searching of
DM relics left over from the Big Bang, and indirect detection (ID) experiments
designed to detect the products of DM annihilations within the solar interior
or galactic halo. Detection of DM particles using multiple strategies provides
complementary information that may shed light on the new physics associated
with the dark matter sector. In contrast to the mSUGRA model where the measured
cold DM relic density restricts us to special regions mostly on the edge of the
m_0-m_{1/2} plane, the entire parameter plane becomes allowed if the
universality assumption is relaxed in models with just one additional
parameter. Then, thermally produced neutralinos with a well-tempered mix of
wino, bino and higgsino components, or with a mass adjusted so that their
annihilation in the early universe is Higgs-resonance-enhanced, can be the DM.
Well-tempered neutralinos typically yield heightened rates for DD and ID
experiments compared to generic predictions from minimal supergravity. If
instead DM consists of axinos (possibly together with axions) or gravitinos,
then there exists the possibility of detection of quasi-stable next-to-lightest
SUSY particles at colliding beam experiments, with especially striking
consequences if the NLSP is charged, but no DD or ID detection. The exception
for mixed axion/axino DM is that DD of axions may be possible.Comment: 28 pages, 11 eps figures; invited contribution to NJP Focus Issue on
"Dark Matter and Particle Physics