3 research outputs found
Renormalization Ambiguities in Chern-Simons Theory
We introduce a new family of gauge invariant regularizations of Chern-Simons
theories which generate one-loop renormalizations of the coupling constant of
the form where can take any arbitrary integer value. In
the particular case we get an explicit example of a gauge invariant
regularization which does not generate radiative corrections to the bare
coupling constant. This ambiguity in the radiative corrections to is
reminiscent of the Coste-L\"uscher results for the parity anomaly in (2+1)
fermionic effective actions.Comment: 10 pages, harvmac, no changes, 1 Postscript figure (now included
Non-Universal Soft SUSY Breaking and Dark Matter
An analysis is given of the effects of non-universal soft SUSY breaking
masses in the Higgs sector and in the third generation squark sector, and it is
shown that they are highly coupled. Analytic expressions are obtained for their
effects on the parameters and on the third generation squark masses.
Non-universality effects on dark matter event rates in neutralino-nucleus
scattering are analysed. It is found that the effects are maximal in the range
~GeV where the relic density is governed by the Z and
Higgs poles. In this range the minimum event rates can be increased or
decreased by factors of O(10) depending on the sign of non-universality. Above
this range Landau pole effects arising from the heavy top mass tend to suppress
the non-universality effects. The effect of more precise measurements of
cosmological parameters on event rates, which is expected to occur in the next
round of COBE like sattelite experiments, is also investigated. Implications
for the analysis for dark matter searches are discussed.Comment: 28 pages, latex, and 7 fig
Predictions of Neutralino Dark Matter Event Rates in Minimal Supergravity Unification
A detailed analysis of dark matter event rates in minimal supergravity models
(MSGM) is given. It is shown analytically that the lightest neutralino the
is the LSP over almost all of the parameter space, and
hence the natural candidate for cold dark matter (CDM). The radiative breaking
of constraints are shown to be crucial in determining the
expected event rates. Approximate analytic formulae are obtained to determine
the gaugino-higgsino content of the particle.From this one
can deduce the behavior of the event rates as one varies the SUSY soft breaking
parameters and tan . The constraint on the event rates due to the
recently measured decay is calculated. It is seen that
this data eliminates most of the parameter space where (the Higgs mixing
parameter) and (the t-quark cubic soft breaking parameter) have the same
sign. Since the t-quark is close to its Landau pole, is restricted to be
mostly positive, and so most of the part of the parameter space is
eliminated...Comment: Revised version for easier TeXing, with some typos corrected. 25
pages + 12 figs.The figs can be faxed on request