407 research outputs found
Improved Probability Method for Estimating Signal in the Presence of Background
A suggestion is made for improving the Feldman Cousins method of estimating
signal counts in the presence of background. The method concentrates on finding
essential information about the signal and ignoring extraneous information
about background. An appropriate method is found which uses the condition that
the number of background events obtained does not exceed the total number of
events obtained. Several alternative approaches are explored.Comment: Modified 12/21 for singlespace to save trees, 9 pages, 1 figure.
Modified 8/11/99 to add small modifications made for the Phys. Rev. articl
Charged-current neutrino-208Pb reactions
We present theoretical results on the non flux-averaged
and
reaction cross sections, obtained within the charge-exchange
Random-Phase-Approximation. A detailed knowledge of these cross sections is
important in different contexts. In particular, it is necessary to assess the
possibility of using lead as a detector in future experiments on supernova
neutrinos, such as OMNIS and LAND, and eventually detect neutrino oscillation
signals by exploiting the spectroscopic properties of . We discuss
the present status on the theoretical predictions of the reaction cross
sections.Comment: 5 pages, latex, 3 figures. added discussion on present status,
Submitted to Phys.Rev.
Neutrino Masses and Mixing one Decade from Now
We review the status of neutrino masses and mixings in the light of the solar
and atmospheric neutrino data. The result from the LSND experiment is also
considered. We discuss the present knowledge and the expected sensitivity to
the neutrino mixing parameters in the simplest schemes proposed to reconcile
these data some of which include a light sterile neutrino in addition to the
three standard ones.Comment: 16 pages Latex file using elsart.sty. Seven postscript figures
included. Talk given at the ICFA/ECFA Workshop "Neutrino Factories based on
Muon Storage Rings, nu-FACT99", Lyon, July 1999. Typo in Eq. 8 correcte
Microscopic theories of neutrino-^{12}C reactions
In view of the recent experiments on neutrino oscillations performed by the
LSND and KARMEN collaborations as well as of future experiments, we present new
theoretical results of the flux averaged and
cross sections. The approaches used are
charge-exchange RPA, charge-exchange RPA among quasi-particles (QRPA) and the
Shell Model. With a large-scale shell model calculation the exclusive cross
sections are in nice agreement with the experimental values for both reactions.
The inclusive cross section for coming from the decay-in-flight of
is to be compared to the experimental value
of , while the one due to
coming from the decay-at-rest of is which
agrees within experimental error bars with the measured values. The shell model
prediction for the decay-in-flight neutrino cross section is reduced compared
to the RPA one. This is mainly due to the different kind of correlations taken
into account in the calculation of the spin modes and partially due to the
shell-model configuration basis which is not large enough, as we show using
arguments based on sum-rules.Comment: 17 pages, latex, 5 figure
Linking solar and long baseline terrestrial neutrino experiments
We show that in the framework of three light neutrino species with
hierarchical masses and assuming no fine tuning between the entries of the
neutrino mass matrix, one can use the solar neutrino data to obtain information
on the element of the lepton mixing matrix. Conversely, a measurement
of in atmospheric or long baseline accelerator or reactor neutrino
experiments would help discriminate between possible oscillation solutions of
the solar neutrino problem.Comment: revtex, 4 pages, no figures. Discussion of the LOW solution modified;
results unchanged. References adde
Muon-anti-neutrino <---> electron-anti-neutrino mixing: analysis of recent indications and implications for neutrino oscillation phenomenology
We reanalyze the recent data from the Liquid Scintillator Neutrino Detector
(LSND) experiment, that might indicate anti-nu_muanti-nu_e mixing. This
indication is not completely excluded by the negative results of established
accelerator and reactor neutrino oscillation searches. We quantify the region
of compatibility by means of a thorough statistical analysis of all the
available data, assuming both two-flavor and three-flavor neutrino
oscillations. The implications for various theoretical scenarios and for future
oscillation searches are studied. The relaxation of the LSND constraints under
different assumptions in the statistical analysis is also investigated.Comment: 17 pages (RevTeX) + 9 figures (Postscript) included with epsfig.st
Measurements of Charged Current Reactions of on
Charged Current reactions of on have been studied using a
decay-at-rest beam at the Los Alamos Neutron Science Center.
The cross section for the exclusive reaction
was measured to be cm. The observed
energy dependence of the cross section and angular distribution of the outgoing
electron agree well with theoretical expectations. Measurements are also
presented for inclusive transitions to excited states,
and compared with theoretical expectations. The
measured cross section, cm, is somewhat
lower than previous measurements and than a continuum random phase
approximation calculation. It is in better agreement with a recent shell model
calculation.Comment: 34 pages, 18 figures, accepted to PRC, replaced with the accepted on
Signals of R-parity violating supersymmetry in neutrino scattering at muon storage rings
Neutrino oscillation signals at muon storage rings can be faked by
supersymmetric (SUSY) interactions in an R-parity violating scenario. We
investigate the -appearance signals for both long-baseline and near-site
experiments, and conclude that the latter is of great use in distinguishing
between oscillation and SUSY effects. On the other hand, SUSY can cause a
manifold increase in the event rate for wrong-sign muons at a long-baseline
setting, thereby providing us with signatures of new physics.Comment: 7 pages LaTeX, 4 ps figures, accepted for publication in Phys. Rev.
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