Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSearch for Baryons in the Radiative Penguin Decay b--> s gamma
113
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We have searched for the baryon-containing radiative penguin decays B^- -> Lambda p-bar gamma and B^- -> Sigma^0 p-bar gamma, using a sample of 9.7 million BBbar events collected at the Upsilon(4S) with the CLEO detector. We find no evidence for either, and set 90% confidence level upper limits for photons with B rest frame energy greater than 2.0 GeV of [Br(B^- -> Lambda p-bar gamma) + 0.3 Br(B^- -> Sigma^0 p-bar gamma)] < 3.3 x 10^-6, [Br(B^- -> Sigma^0 p-bar gamma) + 0.4 Br(B^- -> Lambda p-bar gamma)] < 6.4 x 10^-6. From the latter, we estimate (for photons with B rest frame energy greater than 2.0 GeV) Br(B -> X_s gamma, X_s containing baryons) < 3.8 x 10^-5. This limit implies upper limits on corrections to CLEOs recent measurement of branching fraction, mean photon energy, and variance in photon energy from b -> s gamma that are less than half the combined statistical and systematic errors quoted on these quantities.
rate research
Read More
An overview of the measurements of b->sgamma, b->dgamma and b->sll penguin transitions at the B Factories is presented.
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.
A measurement of the photon polarization in radiative penguin $B$ decays provides a test of the Standard Model and a probe for New Physics, that can lead to a deviation from the Standard Model prediction of left-handed photons in $bto s gamma$. We propose a new method to measure the photon polarization using the baryonic decay $B^- to Lambdabar{p} gamma$. The $P$-violating $Lambda$-hyperon decay allows a measurement of the $Lambda$ helicity to be performed, which can be uniquely related to the photon polarization in a model-independent way. The $B^- to Lambdabar{p} gamma$ decay was recently measured to have a large branching fraction providing a possibility to get meaningful results with the data already available at LHC and B-factory experiments. An increase of the $B$-meson sample at high luminosity LHC experiments and Belle II should provide a really stringent test by using this method already in the near future.
A search for the charmless $B^{0}_{s} to eta^{prime}phi$ decay is performed using $pp$ collision data collected by the LHCb experiment at centre-of-mass energies of $7$ and $8$ TeV, corresponding to an integrated luminosity of 3 fb$^{-1}$. No signal is observed and upper limits on the $B^{0}_{s} to eta^{prime}phi$ branching fraction are set to $0.82times 10^{-6}$ at $90%$ and $1.01times 10^{-6}$ at $95%$ confidence level.
Using an electron-positron collision data sample of 2.93 fb$^{-1}$ collected at a center-of-mass energy of $sqrt{s}=3.773$ GeV with the BESIII detector, we present the first search for the radiative leptonic decay $D^{+} rightarrow gamma e^{+}{ u}_{e}$. The analysis is performed with a double tag method. We do not observe a significant $D^{+} rightarrow gamma e^{+}{ u}_{e}$ signal, and obtain an upper limit on the branching fraction of $D^{+} rightarrow gamma e^{+}{ u}_{e}$ decay with the energy of radiative photon larger than 10 MeV of $3.0times10^{-5}$ at the 90% confidence level.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
