We estimate the beyond the Standard Model (SM) contribution to the Bs,d→γγ double radiative decay in the framework of the model with one universal extra dimension. This contribution gives a ∼3(6)% ...enhancement of the branching ratio calculated in the SM for Bs(d)→γγ (without QCD corrections).
COMET Phase-I technical design report Abramishvili, R; Adamov, G; Allin, A ...
Progress of theoretical and experimental physics,
03/2020, Letnik:
2020, Številka:
3
Journal Article
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Abstract
The Technical Design for the COMET Phase-I experiment is presented in this paper. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into ...electrons in the field of an aluminum nucleus ($\mu$–$e$ conversion, $\mu^{-}N \rightarrow e^{-}N$); a lepton flavor-violating process. The experimental sensitivity goal for this process in the Phase-I experiment is $3.1\times10^{-15}$, or 90% upper limit of a branching ratio of $7\times 10^{-15}$, which is a factor of 100 improvement over the existing limit. The expected number of background events is 0.032. To achieve the target sensitivity and background level, the 3.2 kW 8 GeV proton beam from J-PARC will be used. Two types of detectors, CyDet and StrECAL, will be used for detecting the $\mu$–$e$ conversion events, and for measuring the beam-related background events in view of the Phase-II experiment, respectively. Results from simulation on signal and background estimations are also described.
In case of neuropathic forms, infection is the cause of tissue nekros, while - in case of neuroischemic forms, it's critical ischemia. Antibacterial therapy is present in all cases of neuroischemic ...form, not dependent on the signs of infection, Though, in case of neuropathic forms, a course of antibiotics is prescribed only in case of the attachment of infection. Infected neuroischemic ulcer is characterized of acube development (infection+ischemia), unlike infections neuropathic, ulces. The researches showed that 42 patients (40%) suffered from neuropathic form and 63(60%) - from neuroischemic form. In purulent zones anaerobic flora was revealed in 77.3%, aerobic flora - 17.7%, the rise of microflora was not indicated in 5% of cases. Most often, with 43.6% St. aureus was found out, and from the association of microbes - st. aureus + Str. pyogenes - 8.7%. Was the level of bacterial pollution and varied from 105 to 10(12). The highest sensibility was shown towards Tienam (98.9%). The most acceptable and productive form of treatment turned our to be the following combination phtorchinolyns+aminoglycosides. Out of 105 patients 34 amputations were done + 6 tall, 10 large (more than a half) and 18 small (up to the middle of the foot). In 71 cases we successfully managed to stop infections processes and get rid of amputations.
Contributions to the Bs(d) → γγ decay amplitude beyond the Standard Model are estimated within a model featuring one universal extra dimension. It is found that these additional contributions may ...amount to 6 or 7% of the branching ratios evaluated within the Standard Model.
Flavor-changing radiative lepton decays of the l{sub i} {sup {yields}} l{sub j{gamma}} type are studied within a model involving a universal extra dimension. Loop amplitudes where intermediate ...fermions and scalar bosons have commensurate masses may be quite large since the quadratic suppression factor reduces to a linear one in this case. The situation where fermions and scalar bosons have commensurate masses in a loop is realized in a model featuring universal extra dimensions. The contribution of Kaluza-Klein towers to the l{sub i} {sup {yields}} l{sub j{gamma}} decay amplitude is explicitly calculated. However, the enhancement expected in the amplitude on the basis of general considerations disappears because of the maximal degeneracy of massive-neutrino tower modes associated with different generations.
B-mesons double radiative decays
B
s
→
γγ,
B
d
→
γγ are investigated in frame of supersymmetric extension of the standard model. The branching ratios are calculated.
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