Observation potential for \chi_b at the Tevatron and LHC

We confirm the results of previous works that the internal motion of quarks inside charmonium mesons increases the cross section of the process $e^+e^-\to$J/\psi\eta_c$. We also show, that this effect increases the widths of the scalar meson decay into two vector ones and state that the decays$\chi_{b0,2}\to2J/\psi$ can be used to detect these scalar mesons at Tevatron and LHC colliders.Comment: 13 pages, 5 figures, error in fig.3 correcte

Systematics of heavy quarkonia from Regge trajectories on (n,M2)(n,M^2) and (M2,J)(M^2,J) planes

In this paper we show that heavy quarckonium states, similar to light mesons, form Regge trajectories in $(n,M^2)$ and $(M^2,J)$ planes and the slope of these trajectories is independent on the quantum numbers of the mesons. This fact can be useful for the prediction of the masses of heavy quarkonia and the determination of the quantum numbers of the newly discovered states.Comment: 10 pages, 2 figures, 2 tables; some refrences are added, comparison with QCD sum rules result is presente

Inclusive B-Meson Production at the LHC in the GM-VFN Scheme

We calculate the next-to-leading-order cross section for the inclusive production of B mesons in pp collisions in the general-mass variable-flavor-number scheme, an approach which takes into account the finite mass of the b quarks. We use realistic evolved non-perturbative fragmentation functions obtained from fits to e+e- data and compare results for the transverse-momentum and rapidity distributions at a center-of-mass energy of 7 TeV with recent data from the CMS Collaboration. We find good agreement, in particular at large values of pT.Comment: Minor changes to the text, accepted for publication in Phys. Rev.

Spectroscopy of BcB_{c} meson in a semi-relativistic quark model using the shifted large-N expansion method

We calculate the $c\bar{b}$ mass spectrum, the splitting values and some other properties in the framework of the semi-relativistic equation by applying the shifted large-N expansion technique. We use seven different central potentials together with an improved QCD-motivated interquark potentials calculated to two loops in the modified minimal-subtraction $$ scheme. The parameters of these potentials are fitted to generate the semi-relativistic bound states of $c\bar{b}$ quarkonium system in close conformity with the experimental and the present available calculated center-of-gravity (c.o.g.) data. Calculations of the energy bound states are carried out up to third order. Our results are in excellent fit with the results of the other works.Comment: 3

SVD Approach to Data Unfolding

Distributions measured in high energy physics experiments are usually distorted and/or transformed by various detector effects. A regularization method for unfolding these distributions is re-formulated in terms of the Singular Value Decomposition (SVD) of the response matrix. A relatively simple, yet quite efficient unfolding procedure is explained in detail. The concise linear algorithm results in a straightforward implementation with full error propagation, including the complete covariance matrix and its inverse. Several improvements upon widely used procedures are proposed, and recommendations are given how to simplify the task by the proper choice of the matrix. Ways of determining the optimal value of the regularization parameter are suggested and discussed, and several examples illustrating the use of the method are presented.Comment: 22 page

Hard Probe Capabilities of CMS in Heavy Ion Collisions at the LHC

Heavy ion collisions at the Large Hadron Collider (LHC) will produce strongly interacting matter at unprecedented energy densities. At LHC collision energies, new hard probes of the dense initial collision system will become readily available. We present an overview of the capabilities of the Compact Muon Solenoid (CMS) detector to use these probes for a detailed study of QCD phenomenology at the highest energy densities.Comment: Proceedings for Hard Probes 2006, Asilomar; CMS Conference Report 2006/06

Intrinsic Charm Contribution to Double Quarkonium Hadroproduction

Double $J/\psi$ production has been observed by the NA3 collaboration in $\pi N$ and $p N$ collisions with a cross section of the order of 20-30 pb. The $\psi \psi$ pairs measured in $\pi^-$ nucleus interactions at 150 and 280 GeV$/c$ are observed to carry an anomalously large fraction of the projectile momentum in the laboratory frame, $x_{\psi \psi} \geq 0.6$ at 150 GeV$/c$ and $\geq 0.4$ at 280 GeV$/c$. We postulate that these forward $\psi \psi$ pairs are created by the materialization of Fock states in the projectile containing two pairs of intrinsic $c \overline c$ quarks. We calculate the overlap of the charmonium states with the $|\overline u d c \overline c c \overline c \rangle$ Fock state as described by the intrinsic charm model and find that the $\pi^- N \rightarrow \psi \psi$ longitudinal momentum and invariant mass distributions are both well reproduced. We also discuss double $J/\psi$ production in $pN$ interactions and the implications for other heavy quarkonium production channels in QCD.Comment: Revtex, APS style, 7 pages, 3 figures in uuencoded fil

QCD Mechanisms for Double Quarkonium and Open Heavy Meson Hadroproduction

Double $J/\psi$ production on the order of 20-30 pb has been observed by the NA3 collaboration. These $\psi \psi$ pairs, measured in $\pi^- N$ interactions at 150 and 280 GeV$/c$ and in $pN$ interactions at 400 GeV$/c$, carry a large fraction of the projectile momentum, $x_{\psi \psi} \geq 0.6$ for the 150 GeV$/c$ beam and $\geq 0.4$ at 280 GeV$/c$. We examine several sources of $\psi \psi$ pair production within QCD, including ${\cal O}(\alpha_s^4)$ $\psi \psi$ production, leading-twist $b \overline b$ production and decay, and the materialization of heavy-quark Fock states in the projectile. We estimate the production cross section and the single and double $J/\psi$ momentum and mass distributions for each, comparing the results with the NA3 data, and predict $\psi \psi$ production in $pN$ interactions at 800 GeV$/c$, accessible to current fixed-target experiments. We also discuss the observable implications of open heavy meson pair production from the intrinsic heavy quark Fock states.Comment: Revtex, APS style, 16 pages, 15 figures available as uuencoded postscript files (or ps files) from the Autho

On Instanton Contributions to the tau Hadronic Width

Comparing the results of finite energy and Borel transformed sum rules for the difference of vector and axial vector current correlators we evaluate the instanton contributions to the $\tau$ hadronic width. In contrast to an explicit theoretical calculation we find that the instanton contributions to the $\tau$ hadronic width are much smaller than the standard nonperturbative corrections.Comment: 6 pages, Latex fil

Estimating the effects of Bose-Einstein correlations on the W mass measurement at LEP2

The influence of Bose-Einstein correlations on the determination of the mass of the W boson in e+e- -> WW -> 4jet events at LEP2 energies is studied, using a global event weighting method. We find that it is possible to keep the systematic error on the W mass from this source below 20 MeV, if suitable precautions are taken in the experimental analysis.Comment: 12 pages including 3 .eps figures. Paper revised to correct for a software bug which overestimated heavy quark contributio