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Post Info TOPIC: Super-Kamiokande
Blobrana


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RE: Super-Kamiokande
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Title: Could a reported 2007 analysis of Super-Kamiokande data have missed a detectable supernova signal from Andromeda?
Authors: Robert Ehrlich

According to a 2007 paper there was no evidence for a neutrino "burst" of two or more events in Super-Kamiokande (SK) during the entire period of data-taking from 1996 to 2005 from Andromeda or anywhere else. It may seem presumptuous for the author to suggest that this carefully done analysis may have missed a clearly detectable signal, but that is indeed the case. A new search should be performed using an alternative method, which depends on the hypothesis that two of the neutrino mass eigenstates have masses 4.0 eV and 21.4 eV which was inferred from an analysis of the SN 1987A data. Although one might argue that the hypothesis of such large neutrino masses is remote, there is a way they could be compatible with observed upper limits on the electron neutrino mass and the sum of the neutrino masses from cosmology involving a third tachyonic (m^2<0) eigenstate. Given the importance of a positive supernova search result, and the ease of conducting it using existing SK data, there would seem to be little reason not to do it.

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Blobrana


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Title: New Limits on Dark Matter from Super-Kamiokande
Authors: Rolf Kappl, Martin Wolfgang Winkler

The signals observed at the direct detection experiments DAMA, CoGeNT and CRESST could be explained by light WIMPs with sizeable spin-independent cross sections with nucleons. The capture and subsequent annihilation of such particles in the sun would induce neutrino signals in the GeV range which may be observed at Super-Kamiokande. We determine the rate of upward stopping muons and fully contained events at Super-Kamiokande for various possible WIMP annihilation channels. This allows us to provide strong constraints on the cross section of WIMPs with nucleons. We find that the DAMA and CoGeNT signals are inconsistent with standard thermal WIMPs annihilating dominantly into neutrino or tau pairs. We also provide limits for spin-dependent WIMP nucleus scattering for masses up to 80 GeV. These exclude the DAMA favored region if WIMPs annihilate even subdominantly into neutrinos, taus, bottoms or charms.

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Blobrana


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It's taken a decade of work and cost a million pounds but a massive particle detector designed and built in the UK is being installed at the heart of a groundbreaking Japanese experiment.
The detectors will be looking for neutrino particles in an experiment that aims to answer some of the big questions in physics.
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Blobrana


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Tokai-to-Kamioka experiment
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World's most sensitive neutrino experiment begins

An intrepid subatomic particle has travelled through the bedrock of Japan and triggered a detector on the other side of the country, heralding a new attempt to probe the mystery of neutrino oscillations. The result could take us closer to answering one very big question - why is the universe full of matter?
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Blobrana


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Astrophysical Neutrino Point Sources
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Title: Search for Astrophysical Neutrino Point Sources at Super-Kamiokande
Authors: E. Thrane, for the Super-Kamiokande Collaboration
(Version v3)

It has been hypothesised that large fluxes of neutrinos may be created in astrophysical "cosmic accelerators." The primary background for a search for astrophysical neutrinos comes from atmospheric neutrinos, which do not exhibit the pointlike directional clustering that characterises a distant astrophysical signal. We perform a search for neutrino point sources using the upward-going muon data from three phases of operation (SK-I, SK-II, and SK-III) spanning 2623 days of live time taken from April 1, 1996 to August 11, 2007. The search looks for signals from suspected galactic and extragalactic sources, transient sources, and unexpected sources. We find interesting signatures from two objects--RX J1713.7-3946 (97.5% CL) and GRB 991004D (95.3% CL)--but the signatures lack compelling statistical significance given trial factors. We set limits on the flux and fluence of neutrino point sources above energies of 1.6 GeV.

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Blobrana


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Super-Kamiokande
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Title: Recent Results from Super-Kamiokande
Authors: H. Sekiya, for the Super-Kamiokande Collaboration
(Version v2)

The recent results on the oscillation analyses of solar neutrino and the atmospheric neutrino measurements in Super-Kamiokande are presented. Recent status of the detector is also reported.

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