Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userNucleon/Hyperon Physics at BES
79
0
0.0
(
0
)
Authors
Stephen Lars Olsen
Ask ChatGPT about the research
No Arabic abstract
The year 2019 marks the 30th anniversary of BES and the 100th anniversary of Rutherfords discovery of the proton. In spite of the fact that when BES operations started the proton was already 70 years old and the strange hyperons were all over 25, BES continues to make important and unique measurements of nucleon and hyperon properties, including some interesting discoveries.
rate research
Read More
This physics book provides detailed discussions on important topics in $tau$-charm physics that will be explored during the next few years at bes3 . Both theoretical and experimental issues are covered, including extensive reviews of recent theoretical developments and experimental techniques. Among the subjects covered are: innovations in Partial Wave Analysis (PWA), theoretical and experimental techniques for Dalitz-plot analyses, analysis tools to extract absolute branching fractions and measurements of decay constants, form factors, and CP-violation and DzDzb-oscillation parameters. Programs of QCD studies and near-threshold tau-lepton physics measurements are also discussed.
The recent observations of the purely leptonic decay $Ds to mu^+ u_{mu}$ and $tau^+ u_{tau}$ at CLEO-c and $B$ factory may allow a possible contribution from a charged Higgs boson. One such measurement of the decay constant $f_{D_s}$ differs from the most precise unquenched lattice QCD calculation by 4 $sigma$ level. Meanwhile, the measured ratio, ${cal BR}(Ds to mu^+ u_{mu})$ / ${cal BR}(Dp to mu^+ u_{mu})$, is larger than the standard model prediction at 2.0$sigma$ level. We discuss that the precise measurement of the ratio ${cal BR}(Ds to mu^+ u_{mu})$ / ${cal BR}(Dp to mu^+ u_{mu})$ at BES-III will shed light on the presence of new intermediate particles by comparing the theoretical predictions, especially, the predictions of high precise unquenched lattice QCD calculation.
There are about 33, 6.5 and 1.0 pb$^{-1}$ of $e^+e^-$ annihilation data have been taken around the center-of-mass energies of $sqrt s=$ 3.773 GeV, at $sqrt s=$ 3.650 GeV and at $sqrt s=$ 3.6648 GeV, respectively, with the BES-II detector at the BEPC collider. By analyzing these data sets, we have measured the branching fraction for $psi(3770)to$ non-$Dbar D$ by several different methods; and have observed an anomalous line shape of $sigma^{e^+e^-to{rm hadrons}}$ in energy region from 3.65 to 3.87 GeV; and have measured the line shapes of the $D^+D^-$, $D^0bar D^0$ and $Dbar D$ production and together with the ratios of the production rates of $D^+D^-$ and $D^0bar D^0$ in $e^+e^-$ annihilation around the $psi(3770)$ resonance.
We outline the opportunities for spin physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton LHC beam extracted by a bent crystal. In particular, we focus on the study of single transverse spin asymetries with the polarisation of the target.
We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERNs Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at the Planck Scale. We discuss some of the particle detection techniques used in ALPHA. Preliminary results from commissioning studies of a partial system of the ALPHA Si vertex detector are presented, the results of which highlight the power of annihilation vertex detection capability in antihydrogen studies.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
