118586941
Cornell Potential Parameters for S-wave Heavy Quarkonia
We compute derived quantities for various values of the model parameter of the Cornell potential model for the S-wave heavy quarkonia with radial quantum numbers n=1, 2, and 3. Our results can be used to determine leading and relative-order-v^2 nonrelativistic quantum chromodynamics matrix elements for S-wave charmonia and bottomonia such as psi(2S), eta_c(2S), and Upsilon(nS) for n=1, 2, and 3. These matrix elements will be essential ingredients for resumming relativistic corrections to processes involving those S-wave heavy quarkonium states.
26919092
A Measurement of the Michel Parameters in Leptonic Decays of the Tau
We have measured the spectral shape Michel parameters {rho} and {eta} using leptonic decays of the {tau}, recorded by the CLEO II detector. Assuming e-{mu} universality, we find {rho}{sub e{mu}}= 0.735 {+-} 0.013 {+-} 0.008 and {eta}{sub e{mu}} = 0.015 {+-} 0.061 {+-} 0.062, where the first error is statistical and the second systematic.
118538298
Exclusive heavy quarkonium + γ production from e+e-annihilation into a virtual photon
We compute the cross section for exclusive production of a photon associated with a heavy quarkonium H of charge-conjugation parity C=+1 from e{sup +}e{sup -} annihilation into a virtual photon at the center-of-momentum energy {radical}(s)=10.58 GeV. The nonrelativistic QCD factorization formulas for the differential and total cross sections are obtained at leading order in the strong coupling and in the relative velocity of the heavy quark in the quarkonium rest frame. The predicted cross sections for the S-wave spin-singlet cases are about 80 fb and 50 fb for H={eta}{sub c} and {eta}{sub c}(2S), respectively. Among P-wave spin-triplet charmonia, {chi}{sub c1} has a particularly large cross section of about 14 fb. The cross sections for bottomonium states {eta}{sub b} and {chi}{sub bJ} are about 3 fb. A rough estimate of the background reveals that the signal significances for charmonium processes are sufficiently large enough to be detected with ease with the integrated luminosities available at the present B factories.
124343131
Exclusive spin-2 glueball production associated with J/ψ from e +e- annihilation
116621787
Polarization of prompt J/ in proton-proton collisions at RHIC
Within the framework of the nonrelativistic QCD (NRQCD) factorization approach, we compute the polarization of prompt J/{psi} produced at the Brookhaven's Relativistic Heavy-Ion Collider from proton-proton collisions at the center-of-momentum energy {radical}(s)=200 GeV. The perturbative contributions are computed at leading order in the strong coupling constant. The prediction reveals that the color-singlet contribution severely underestimates the PHENIX preliminary data for the differential cross section integrated over the rapidity range |y|<0.35 and its contribution is strongly transversely polarized, which disagrees with the PHENIX preliminary data. After including the color-octet contributions, we find that the NRQCD predictions for both the cross section and polarization over the transverse-momentum range 1.5 GeV<p{sub T}<5 GeV (1.5 GeV<p{sub T}<2 GeV) integrated over the rapidity range |y|<0.35 (1.2<|y|<2.2) agree with the data within errors.
125995563
Double quarkonium production at the LHC
118555774
Radiative corrections to scalar masses and mixing in a scale invariant two Higgs doublet model
We study the Higgs boson mass spectrum of a classical scale invariant realization of the two Higgs doublet model (SI-2HDM). The classical scale symmetry of the theory is explicitly broken by quantum loop effects due to gauge interactions, Higgs self-couplings and top quark Yukawa couplings. We determine the allowed parameter space compatible with perturbative unitarity and electroweak precision data. Taking into account the LEP and the recent LHC exclusion limits on a standard-model-like Higgs boson HSM, we obtain rather strict constraints on the mass spectrum of the heavy Higgs sector of the SI-2HDM. In particular, if MHSM 125 GeV, the SI-2HDM strongly favors scenarios in which at least one of the nonstandard neutral Higgs bosons has a mass close to 400 GeV and is generically degenerate with the charged Higgs boson, whilst the third neutral Higgs scalar is lighter than 500 GeV.
123566403
Search for squarks and gluinos with the ATLAS detector in final states with jets and missing transverse momentum using 4.7 fb-1 of √s = 7 TeV proton-proton collision data
A search for squarks and gluinos in final states containing jets, missing transverse momentum and no high-p(T) electrons or muons is presented. The data represent the complete sample recorded in 2011 by the ATLAS experiment in 7 TeV proton-proton collisions at the Large Hadron Collider, with a total integrated luminosity of 4.7 fb(-1). No excess above the Standard Model background expectation is observed. Gluino masses below 860 GeV and squark masses below 1320 GeV are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet and a massless neutralino, for squark or gluino masses below 2 TeV, respectively. Squarks and gluinos with equal masses below 1410 GeV are excluded. In minimal supergravity/constrained minimal supersymmetric Standard Model models with tan beta = 10, A(0) = 0 and mu > 0, squarks and gluinos of equal mass are excluded for masses below 1360 GeV. Constraints are also placed on the parameter space of supersymmetric models with compressed spectra. These limits considerably extend the region of supersymmetric parameter space excluded by previous measurements with the ATLAS detector.
73540853
Geometrical properties of the trans-spherical solutions in higher dimensions
We investigate the geometrical properties of static vacuum p-brane solutions of Einstein gravity in D=n+p+3 dimensions, which have spherical symmetry of S{sup n+1} orthogonal to the p directions and which are invariant under the translation along them. The solutions are characterized by the mass density and p number of tension densities. The causal structure of the higher-dimensional solutions is essentially the same as that of the five-dimensional ones. Namely, a naked singularity appears for most solutions except for the Schwarzschild black p-brane and the Kaluza-Klein bubble. We show that some important geometric properties such as the area of S{sup n+1} and the total spatial volume are characterized only by the three parameters (the mass density, the sum of tension densities, and the sum of tension density squares), rather than individual tension densities. These geometric properties are analyzed in detail in this parameter space and are compared with those of the five-dimensional case.
119066417
A vector-like heavy quark in the littlest Higgs model
The littlest Higgs model contains a new vector-like heavy quark in the up sector. There are two interesting features of its existence. One is that it extends the 3 × 3 CKM matrix in the standard model to a 4 × 3 matrix and the other is that it allows Z-mediated flavor changing neutral currents at tree level in the up sector but not in the down sector. We examine a few of possible windows in which the Z-mediated flavor changing neutral currents in the littlest Higgs model can be tested.
96502755
Charged-particle multiplicities inppinteractions measured with the ATLAS detector at the LHC
New Journal of Physics The open–access journal for physics Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC The ATLAS Collaboration New Journal of Physics 13 (2011) 053033 (68pp) Received 22 December 2010 Published 19 May 2011 Online at http://www.njp.org/ doi:10.1088/1367-2630/13/5/053033 Measurements √ are presented from proton–proton collisions at centre-of-mass energies of s = 0.9, 2.36 and 7 TeV recorded with the ATLAS detector at the LHC. Events were collected using a single-arm minimum- bias trigger. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the relationship between the mean transverse momentum and charged-particle multiplicity are measured. Measurements in different regions of phase space are shown, providing diffraction-reduced measurements as well as more inclusive ones. The observed distributions are corrected to well-defined phase-space regions, using model-independent corrections. The results are compared to each other and to various Monte Carlo (MC) models, including a new AMBT1 pythia6 tune. In all the kinematic regions considered, the particle multiplicities are higher than predicted by the MC models. The central charged-particle multiplicity per event and unit of pseudorapidity, for tracks √ with p T > 100 MeV, is measured to be 3.483 ± 0.009 (stat) (syst) at s = 0.9 TeV and 5.630 ± 0.003 (stat) ± 0.169 (syst) at s = 7 TeV. Abstract. New Journal of Physics 13 (2011) 053033 © 2011 CERN for the benefit of the ATLAS Collaboration, published under licence by IOP Publishing Ltd for the Institute of Physics and Deutsche Physikalische Gesellschaft. Content may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation and DOI.