6,569 research outputs found
Search for lepton flavor violation via the intense high-energy muon beam
A deep inerastic scattering process \mutau is discussed to study lepton
flavor violation between muons and tau leptons. In supersymmetric models, the
Higgs boson mediated diagrams could be important for this reaction. We find
that at a muon energy () higher than 50 GeV, the predicted cross
section significantly increases due to the contribution from sea -quarks.
The number of produced tau leptons can be at = 300
GeV from muons, whereas events are given at
GeV.Comment: Contribution to the 6th International Workshop on Neutrino Factories
& Superbeams(NuFact04), Jul. 26-Aug. 1, 2004, Osaka Univerisity, Osaka,
Japan, talk given by S.K., to appear in the Proceedings, 3 pages, 4 figure
Belle II iTOP Optics: Design, Construction and Performance
The imaging-Time-of-Propogation (iTOP) counter is a new type of ring-imaging
Cherenkov counter developed for particle identification at the Belle II
experiment. It consists of 16 modules arranged azimuthally around the beam
line. Each module consists of one mirror, one prism and two quartz bar
radiators. Here we describe the design, acceptance test, alignment, gluing and
assembly of the optical components. All iTOP modules have been successfully
assembled and installed in the Belle II detector by the middle of 2016. After
installation, laser and cosmic ray data have been taken to test the performance
of the modules. First results from these tests are presented.Comment: Proceedings of TIPP 2017, May 22 - 26, Beijing, China, 2017;
University of Cincinnati preprint UCHEP-17-07. arXiv admin note: text overlap
with arXiv:1709.0993
An imaging time-of-propagation system for charged particle identification at a super B factory
Super B factories that will further probe the flavor sector of the Standard
Model and physics beyond will demand excellent charged particle identification
(PID), particularly K/pi separation, for momenta up to 4 GeV/c, as well as the
ability to operate under beam backgrounds significantly higher than current B
factory experiments. We describe an Imaging Time-of-Propagation (iTOP) detector
which shows significant potential to meet these requirements. Photons emitted
from charged particle interactions in a Cerenkov radiator bar are internally
reflected to the end of the bar, where they are collected on a compact image
plane using photodetectors with fine spatial segmentation in two dimensions.
Precision measurements of photon arrival time are used to enhance the two
dimensional imaging, allowing the system to provide excellent PID capabilities
within a reduced detector envelope. Results of the ongoing optimization of the
geometric and physical properties of such a detector are presented, as well as
simulated PID performance. Validation of simulations is being performed using a
prototype in a cosmic ray test stand at the University of Hawaii.Comment: 3 pages, 5 figures, submitted to TIPP09 proceeding
Meretojan taudista uutta tietoa kansallisen potilasrekisterin avulla
Tiedot Meretojan taudin eli suomalaisen perinnöllisen gelsoliiniamyloidoosin taudinkulusta ovat tähän saakka perustuneet suhteellisen pieniin potilassarjoihin. Uuden kansallisen FIN-GAR-potilasrekisterin avulla voidaan paremmin kartoittaa taudin oireita ja niiden yleisyyttä sekä sen luonnollista kulkua. Potilasrekisteriin on tähän mennessä kerätty tiedot 235 potilaasta, ja siihen toivotaan edelleen täydennystä. Rekisterin mukaan ensioireet alkavat yleensä silmistä. Taudin ensisijainen diagnostinen löydös on potilaalle tyypillisesti jo 20–30-vuotiaana kehittyvä sarveiskalvon verkkomainen rappeuma. Muut oireet ja löydökset kehittyvät suurin piirtein samanaikaisesti, mediaanien osuessa 50 ja 60 ikävuoden välille. Naisilla oireet kehittyvät keskimäärin aiemmin ja erityisesti silmäoireet ovat yleisempiä kuin miehillä. Rannekanavaoireyhtymä, sydämentahdistin ja munuaisensiirrot ovat rekisterin potilailla huomattavasti yleisempiä kuin normaaliväestössä. Näiden tarkkaa patologista yhteyttä Meretojan tautiin tutkitaan parhaillaan.Peer reviewe
Flavor and CP Violation Induced by Atmospheric Neutrino Mixing
Neutrino oscillation experiments suggest existence of new flavor-violating
interactions in high energy scale. It may be possible to probe them by the
flavor- and CP-violating processes in leptons and hadrons in the supersymmetric
(SUSY) models. In this article the third-generation flavor violation is
reviewed in the SUSY seesaw model and SUSY SU(5) GUT with the right-handed
neutrinos.Comment: 12 pages. Talk at Fujihara Seminar on Neutrino Mass and Seesaw
Mechanism (SEESAW 1979-2004), Tsukuba, Ibaraki, Japan, 23-25 Feb 200
Probing lepton flavor violation signal via e+ e- (gamma gamma) ---> l(i) anti-l(j) in the littlest Higgs model with T-parity at the ILC
In the littlest Higgs model with T-parity, the new interactions between the
mirror leptons and the Standard Model leptons can induce some lepton flavor
violation (LFV) processes at loop level. We study the possibility of the ILC to
probe the LFV production processes . Our results show that the rates of can reach 1 fb in optimal cases after reasonable kinematical
cuts, which implies that these processes may be observed at the ILC
Lepton flavour violating Higgs Boson decays, tau --> mu gamma and B(s) --> mu+mu- in the constrained MSSM+NR with large tan beta
Realistic predictions are made for the rates of lepton flavour violating
Higgs boson decays, tau --> mu gamma, mu --> e gamma, Bs --> mu+mu-, Bs --> tau
mu and tau --> 3mu, via a top-down analysis of the Minimal Supersymmetric
Standard Model(MSSM) constrained by SU(5) unification with right-handed
Neutrinos and large tan beta. The third family neutrino Yukawa coupling is
chosen to be of order 1, in this way our model bares a significant resemblance
to supersymmetric SO(10). In this framework the large PMNS mixings result in
potentially large lepton flavour violation. Our analysis predicts tau --> mu
gamma and mu --> e gamma rates in the region (10^{-8}-10^{-6}) and
(10^{-15}-10^{-14}) respectively. We also show that the rates for lepton
flavour violating Higgs decays can be as large as 10^{-7}. The non-decoupling
nature of H --> tau mu is observed which leads to its decay rate becoming
comparable to that for tau --> mu gamma for large values of m_0 and M_1/2. We
also find that the present bound on Bs --> mu+mu- is an important constraint on
the rate of lepton flavour violating Higgs decays. The recently measured
Bs-Bsbar mixing parameter Delta Ms is also investigated.Comment: 27 pages, 15 postscript figures, 1 table. Small changes made to the
text and title. Updated references. Bs-Bsbar analysis also include
Lepton Flavour Violating Leptonic/Semileptonic Decays of Charged Leptons in the Minimal Supersymmetric Standard Model
We consider the leptonic and semileptonic (SL) lepton flavour violating (LFV)
decays of the charged leptons in the minimal supersymmetric standard model
(MSSM). The formalism for evaluation of branching fractions for the SL LFV
charged-lepton decays with one or two pseudoscalar mesons, or one vector meson
in the final state, is given. Previous amplitudes for the SL LFV charged-lepton
decays in MSSM are improved, for instance the -penguin amplitude is
corrected to assure the gauge invariance. The decays are studied not only in
the model-independent formulation of the theory in the frame of MSSM, but also
within the frame of the minimal supersymmetric SO(10) model within which the
parameters of the MSSM are determined. The latter model gives predictions for
the neutrino-Dirac Yukawa coupling matrix, once free parameters in the model
are appropriately fixed to accommodate the recent neutrino oscillation data.
Using this unambiguous neutrino-Dirac Yukawa couplings, we calculate the LFV
leptonic and SL decay processes assuming the minimal supergravity scenario. A
very detailed numerical analysis is done to constrain the MSSM parameters.
Numerical results for SL LFV processes are given, for instance for tau -> e
(mu) pi0, tau -> e (mu) eta, tau -> e (mu) eta', tau -> e (mu) rho0, tau -> e
(mu) phi, tau -> e (mu) omega, etc.Comment: 36 pages, 3 tables, 5 .eps figure
Search for the Lepton-Flavor-Violating Decay at Belle
We have searched for the Lepton Flavor Violating decay using a data sample of 84.3 fb accumulated with the Belle detector
at KEK. The -meson was detected through the decay modes: and . No signal candidates are found, and we
obtain an upper limit for the branching fraction at the 90% confidence level.Comment: Submitted to Phys.Rev.Let
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