- ph / 9811361 November 1998 Υ Polarization at HERA - B
نویسندگان
چکیده
The production of Υ mesons in fixed target pN collisions is considered. It is shown that Non-Relativistic QCD predicts Υ states to be produced with sizeable transverse polarization. The possibility of a measurement of the Υ polarization at the HERA-B experiment is discussed. PACS: 13.20.Gd, 13.88.+e, 13.60.Le, 12.38.Qk Alexander von Humboldt Fellow
منابع مشابه
Bottomonium Polarization in Hadroproduction
The polarization of the Υ and χb2 mesons in hadron hadron collisions is considered. It is shown that both states are produced with a noticeable polarization which allows to use forthcoming data of DESY HERA-B and of the RHIC collider experiments to discriminate between the different mechanisms of heavy quarkonia production. PACS: 13.20.Gd, 13.88.+e, 13.60.Le, 12.38.Qk. Alexander von Humboldt Fe...
متن کاملDiffractive Photoproduction of Υ at HERA
Predictions for the diffractive photoproduction of the Υ-family at HERA energies, within the framework of the analysis by Frankfurt, Koepf and Strikman, are presented. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log(Q) accuracy, and the large magnitude of the real part of the amplitude. The resul...
متن کاملBottom Quark Mass from Υ Mesons
The bottom quark pole mass M b is determined using a sum rule which relates the masses and the electronic decay widths of the Υ mesons to large n moments of the vacuum polarization function calculated from nonrelativistic quantum chromodynamics. The complete set of next-to-next-to-leading order (i.e. O(α 2 s , α s v, v 2) where v is the bottom quark c.m. velocity) corrections is calculated and ...
متن کاملDiffractive photoproduction of Υ states at HERA
Cross sections for the diffractive photoproduction of the Υ-family at HERA energies, within the framework of the analysis by Frankfurt, Köpf and Strikman [1,2], are presented. They compare well with the recent preliminary data from ZEUS and H1. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log(Q) a...
متن کاملar X iv : h ep - e x / 06 03 01 5 v 1 8 M ar 2 00 6 Measurement of the Υ Production Cross Section in 920 GeV Fixed - Target Proton - Nucleus Collisions
The proton-nucleon cross section ratio R = Br(Υ → l+l−) · dσ(Υ)/dy|y=0 /σ(J/ψ) has been measured with the HERA-B spectrometer in fixed-target proton-nucleus collisions at 920 GeV proton beam energy corresponding to a proton-nucleon cms energy of √ s = 41.6 GeV. The combined results for the decay channels Υ → e+e− and Υ → μ+μ− yield a ratio R = (9.0±2.1) ·10−6 . The corresponding Υ production cr...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1998