Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSearch for hadronic decays of a light Higgs boson in the radiative decay Upsilon --> gamma A0
123
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We search for hadronic decays of a light Higgs boson (A0) produced in radiative decays of an Upsilon(2S) or Upsilon(3S) meson, Upsilon --> gamma A0. The data have been recorded by the BABAR experiment at the Upsilon(3S) and Upsilon(2S) center of mass energies, and include (121.3 pm 1.2) x 10^6 Upsilon(3S) and (98.3 pm 0.9) x 10^6 Upsilon(2S) mesons. No significant signal is observed. We set 90% confidence level upper limits on the product branching fractions B(Upsilon(nS)-->gamma A0) x B(A0-->hadrons) (n=2 or 3) that range from 1 x 10^{-6} for an A0 mass of 0.3 GeV/c^2 to 8 x 10^{-5} at 7 GeV/c^2.
rate research
Read More
We search for bottomonium states in Upsilon(2S)-> (bb-bar) gamma decays with an integrated luminosity of 24.7fb^-1 recorded at the Upsilon(2S) resonance with the Belle detector at KEK, containing (157.8+-3.6) X 10^6 Upsilon(2S) events. The (bb-bar) system is reconstructed in 26 exclusive hadronic final states composed of charged pions, kaons, protons, and K^0_S mesons. We find no evidence for the state recently observed around 9975 MeV (X_(bb-bar)) in an analysis based on a data sample of 9.3 X 10^6 Upsilon(2S) events collected with the CLEO III detector. We set a 90 % confidence-level upper limit on the branching fraction B[Upsilon(2S)-> X_(bb-bar) gamma] X sum_i{B[X_(bb-bar)-> h_i]}< 4.9 X 10^-6, summed over the exclusive hadronic final states employed in our analysis. This result is an order of magnitude smaller than the measurement reported with CLEO data. We also set an upper limit for the eta_b(1S) state of B[Upsilon(2S)-> eta_b(1S) gamma] X sum_i{B[eta_b(1S)-> h_i]}< 3.7 X 10^-6.
We search for the $J^{PC}=0^{--}$ and $1^{+-}$ light tetraquark states with masses up to 2.46~GeV/$c^2$ in $Upsilon(1S)$ and $Upsilon(2S)$ decays with data samples of $(102pm 2)$ million and $(158pm 4)$ million events, respectively, collected with the Belle detector. No significant signals are observed in any of the studied production modes, and 90% credibility level (C.L.) upper limits on their branching fractions in $Upsilon(1S)$ and $Upsilon(2S)$ decays are obtained. The inclusive branching fractions of the $Upsilon(1S)$ and $Upsilon(2S)$ decays into final states with $f_1(1285)$ are measured to be ${cal B}(Upsilon(1S)to f_1(1285)+anything)=(46pm28({rm stat.})pm13({rm syst.}))times 10^{-4}$ and ${cal B}(Upsilon(2S)to f_1(1285)+anything)=(22pm15({rm stat.})pm6.3({rm syst.}))times 10^{-4}$. The measured $chi_{b2} to J/psi + anything$ branching fraction is measured to be $(1.50pm0.34({rm stat.})pm0.22({rm syst.}))times 10^{-3}$, and 90% C.L. upper limits for the $chi_{b0,b1} to J/psi + anything$ branching fractions are found to be $2.3times 10^{-3}$ and $1.1times 10^{-3}$, respectively. For ${cal B}(chi_{b1} to omega + anything)$, the branching fraction is measured to be $(4.9pm1.3({rm stat.})pm0.6({rm syst.}))times 10^{-2}$. %($<3.68times 10^{-2}$ at 90% C.L.). All results reported here are the first measurements for these modes.
Leptonic decays of vector-states of bottomonium are analized searching for a light pseudoscalar Higgs-like neutral boson manifesting via an apparent breaking of lepton universality.
We explore non-standard Higgs phenomenology in the Gaugephobic Higgs model in which the Higgs can be lighter than the usually quoted current experimental bound. The Higgs propagates in the bulk of a 5D space-time and Electroweak Symmetry Breaking occurs by a combination of boundary conditions in the extra dimension and an elementary Higgs. The Higgs can thus have a significantly suppressed coupling to the other Standard Model fields. A large enough suppression can be found to escape all limits and allow for a Higgs of any mass, which would be associated with the discovery of W and Z Kaluza-Klein resonances at the LHC. The Higgs can be precisely discovered at B-factories while the LHC would be insensitive to it due to high backgrounds. In this letter we study the Higgs discovery mode in Upsilon(3S), Upsilon(2S), and Upsilon(1S) decays, and the model parameter space that will be probed by BaBar, Belle, and CLEO data. In the absence of an early discovery of a heavy Higgs at the LHC, A Super-B factory would be an excellent option to further probe this region.
The first search for the rare radiative decay $Xi_b^- to Xi^- gamma$ is performed using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb$^{-1}$. The $Xi_b- to Xi^- J/psi$ channel is used as normalization. No $Xi_b^- to Xi^- gamma$ signal is found and an upper limit of $mathcal{B}(Xi_b^- to Xi^- gamma) < 1.3 times 10^{-4}$ at 95% confidence level is obtained.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
