Search results for "MBD"
showing 10 items of 646 documents
Theory of slow-light solitons
2005
In the framework of the nonlinear $\Lambda$-model we investigate propagation of solitons in atomic vapors and Bose-Einstein condensates. We show how the complicated nonlinear interplay between fast solitons and slow-light solitons in the $\Lambda$-type media points to the possibility to create optical gates and, thus, to control the optical transparency of the $\Lambda$-type media. We provide an exact analytic description of decelerating, stopping and re-accelerating of slow-light solitons in atomic media in the nonadiabatic regime. Dynamical control over slow-light solitons is realized via a controlling field generated by an auxiliary laser. For a rather general time dependence of the fiel…
Stimulated Raman Adiabatic Passage via bright state in Lambda medium of unequal oscillator strengths
2012
International audience; We consider the population transfer process in a Lambda-type atomic medium of unequal oscillator strengths by stimulated Raman adiabatic passage via bright-state (b-STIRAP) taking into account propagation effects. Using both analytic and numerical methods we show that the population transfer efficiency is sensitive to the ratio q(p)/q(s) of the transition oscillator strengths. We find that the case q(p) > q(s) is more detrimental for population transfer process as compared to the case where q(p) <= q(s). For this case it is possible to increase medium dimensions while permitting efficient population transfer. A criterion determining the interaction adiabaticity in th…
Hidden beauty baryon states in the local hidden gauge approach with heavy quark spin symmetry
2013
Using a coupled-channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-baryon interaction with hidden beauty and obtain several new states of N around 11 GeV. We consider the basis of states eta (b) N, I'N, BI > (b) , BI pound (b) , B (*) I > (b) , B (*) I pound (b) , B (*) I pound (b) (*) and find four basic bound states which correspond to BI pound (b) , BI pound (b) (*) , B (*) I pound (b) and B (*) I pound (b) (*) , decaying mostly into eta (b) N and I'N and with a binding energy about 50-130 MeV with respect to the thresholds of the corresponding channel. All of them have isospin I = 1/2 , and we find no bo…
Search for single production of scalar leptoquarks in pp¯ collisions decaying into muons and quarks with the D0 detector
2007
We report on a search for second generation leptoquarks LQ_2 which decay into a muon plus quark in p\bar{p} collisions at a center-of-mass energy of sqrt{s} = 1.96 TeV in the D0 detector using an integrated luminosity of about 300 pb-1. No evidence for a leptoquark signal is observed and an upper bound on the product of the cross section for single leptoquark production times branching fraction beta into a quark and a muon was determined for second generation scalar leptoquarks as a function of the leptoquark mass. This result has been combined with a previously published D0 search for leptoquark pair production to obtain leptoquark mass limits as a function of the leptoquark-muon-quark cou…
Compositeness of the strange, charm and beauty odd parity $\Lambda$ states
2015
14 pages.- 2 figures.- 5 tables
First measurement of the ratio of branching fractionsB(Λb0→Λc+μ−ν¯μ)/B(Λb0→Λc+π−)
2009
This article presents the first measurement of the ratio of branching fractions B(Lambda(0)(b) -> Lambda(+)(c) mu(-) (nu) over bar (mu))/B(Lambda(0)(b) -> Lambda(+)(c) pi(-)). Measurements in two control samples using the same technique B((B) over bar (0) -> D+ mu(-) (nu) over bar (mu))/B((B) over bar (0) -> D+ pi(-)) and B((B) over bar (0) -> D*(2010)(+) mu(-) (nu) over bar (mu))/B((B) over bar (0) -> D*(2010)(+) pi(-)) are also reported. The analysis uses data from an integrated luminosity of approximately 172 pb(-1) of p (p) over bar collisions at root s = 1: 96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The relative branching fractions are measured to be B(Lambda(…
Measurement of the absolute branching fraction of the inclusive semileptonic $\Lambda_c^+$ decay
2018
Physical review letters 121(25), 251801 (2018). doi:10.1103/PhysRevLett.121.251801
Transport coefficients of self-propelled particles: Reverse perturbations and transverse current correlations
2019
The reverse perturbation method [Phys. Rev. E 59, 4894 (1999)] for shearing simple liquids and measuring their viscosity is extended to the Vicsek model (VM) of active particles [Phys. Rev. Lett. 75, 1226 (1995)] and its metric-free version. The sheared systems exhibit a phenomenon that is similar to the skin effect of an alternating electric current: Momentum that is fed into the boundaries of a layer decays mostly exponentially toward the center of the layer. It is shown how two transport coefficients, i.e., the shear viscosity $\ensuremath{\nu}$ and the momentum amplification coefficient $\ensuremath{\lambda}$, can be obtained by fitting this decay with an analytical solution of the hydr…
A polymer chain trapped between two parallel repulsive walls: A Monte-Carlo test of scaling behavior
1998
An off-lattice bead-spring model of a polymer chain trapped between two parallel walls a distance D apart is studied by Monte-Carlo methods, using chain lengths N in the range $$32 \le N \le 512$$ and distances D from 4 to 32 (in units of the maximum spring extension). The scaling behavior of the coil linear dimensions parallel to the plates and of the force on the walls is studied and discussed with the help of current theoretical predictions. Also the density profiles of the monomers across the slit are obtained and it is shown that the predicted variation with the distance z from a wall, $$\rho (z) \propto {z^{1/\nu }}$$ , is obtained only when one introduces an extrapolation length λ in…
High resolution spectroscopic study ofBeΛ10
2016
Spectroscopy of a Be-10(Lambda) hypernucleus was carried out at JLab Hall C using the (e, e' K+) reaction. A new magnetic spectrometer system (SPL+ HES+ HKS), specifically designed for high resolution hypernuclear spectroscopy, was used to obtain an energy spectrum with a resolution of similar to 0.78 MeV (FWHM). The well-calibrated spectrometer system of the present experiment using p(e, e' K+)Lambda, Sigma(0) reactions allowed us to determine the energy levels; and the binding energy of the ground-state peak (mixture of 1(-) and 2(-) states) was found to be B-Lambda = 8.55 +/- 0.07(stat.) +/- 0.11(sys.) MeV. The result indicates that the ground-state energy is shallower than that of an em…