Measurement of the Transverse Single Spin Asymmetry of pp + p↑p^\uparrow →\rightarrow η\eta + XX at s\sqrt{s} = 200 GeV

The measurement of transverse single spin asymmetries ($A_N$) provides insight into the structure of the nucleon. Several mechanisms have been proposed that attempt to explain $A_N$ based on QCD, and additional measurements of $A_N$ for different processes further constrain these models. Using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC), we study transversely polarized p+p collisions. Results from PHENIX and other experiments show significant asymmetries in the forward region, which could be due to contributions from both the Sivers and the Collins effects. Studying the species as well as the kinematic dependencies of these transverse single spin asymmetries will help to disentangle the origin of the observed asymmetries. Therefore, measurements of $A_N$ with inclusive $\eta$ mesons at forward rapidities are an important tool for the understanding of these asymmetries. In 2008, the PHENIX experiment collected 5.2 pb$^{-1}$ integrated luminosity in $p^\uparrow+p$ collisions at $\sqrt{s}$ = 200 GeV. The status of the asymmetry analysis of $\eta$ mesons at forward rapidity will be shown.Comment: 4 pages, 3 figure

Experimental results on KLK_L decays

Recent measurements by the NA48 at CERN of selected $K_L$ decays are presented. These are the branching ratios and form factors for channels K_L\to \pi^{\pm}\pi^0\e^{\mp}\nu_e (final result), $K_L\to\pi^{\pm}e^{\mp}\nu_e$ and $K_L\to e^+e^-e^+e^-$ (preliminary results).Comment: 4 pages, 5 figures, talk given at QCD'04 Conference, Montpellier, France, 5-9 July 200

Production of the h_c and h_b and Implications for Quarkonium Spectroscopy

The recent observation of the h_c is an important test of QCD calculations and provides constraints on models of quarkonium spectroscopy. In this contribution I discuss some of these implications and describe methods to search for the h_c and h_b via radiative transitions and other means.Comment: Talk presented at the 1st Meeting of the APS Topical Group on Hadronic Physics (Fermilab, Oct 24-26, 2004), 4 pages, 1 figure, uses jpconf. References adde

Section on Prospects for Dark Matter Detection of the White Paper on the Status and Future of Ground-Based TeV Gamma-Ray Astronomy

This is a report on the findings of the dark matter science working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper was commissioned by the American Physical Society, and the full white paper can be found on astro-ph (arXiv:0810.0444). This detailed section discusses the prospects for dark matter detection with future gamma-ray experiments, and the complementarity of gamma-ray measurements with other indirect, direct or accelerator-based searches. We conclude that any comprehensive search for dark matter should include gamma-ray observations, both to identify the dark matter particle (through the charac- teristics of the gamma-ray spectrum) and to measure the distribution of dark matter in galactic halos.Comment: Report from the Dark Matter Science Working group of the APS commissioned White paper on ground-based TeV gamma ray astronomy (19 pages, 9 figures

Effective role of unpolarized nonvalence partons in Drell-Yan single spin asymmetries

We perform numerical simulations of the Sivers effect from single spin asymmetries in Drell-Yan processes on transversely polarized protons. We consider colliding antiprotons and pions at different kinematic conditions of interest for the future planned experiments. We conventionally name "framework I" the results obtained when properly accounting for the various flavor dependent polarized valence contributions in the numerator of the asymmetry, and for the unpolarized nonvalence contribution in its denominator. We name "framework II" the results obtained when taking a suitable flavor average of the valence contributions and neglecting the nonvalence ones. We compare the two methods, also with respect to the input parametrization of the Sivers function which is extracted from data with approximations sometimes intermediate between frameworks I and II. Deviations between the two approaches are found to be small except for dilepton masses below 3 GeV. The Sivers effect is used as a test case; the arguments can be generalized to other interesting azimuthal asymmetries in Drell-Yan processes, such as the Boer-Mulders effect.Comment: 13 pages, 9 figures in eps forma

Re-evaluation of the LHC potential for the measurement of Mw

We present a study of the LHC sensitivity to the W boson mass based on simulation studies. We find that both experimental and phenomenological sources of systematic uncertainties can be strongly constrained with Z measurements: the lineshape is robustly predicted, and its analysis provides an accurate measurement of the detector resolution and absolute scale, while the differential cross-section analysis absorbs most of the strong interaction uncertainties. A sensitivity \delta Mw \sim 7 \MeV for each decay channel (W --> e nu, W --> mu nu), and for an integrated luminosity of 10 fb-1, appears as a reasonable goal

Exploring the Partonic Structure of Hadrons through the Drell-Yan Process

The Drell-Yan process is a standard tool for probing the partonic structure of hadrons. Since the process proceeds through a quark-antiquark annihilation, Drell-Yan scattering possesses a unique ability to selectively probe sea distributions. This review examines the application of Drell-Yan scattering to elucidating the flavor asymmetry of the nucleon's sea and nuclear modifications to the sea quark distributions in unpolarized scattering. Polarized beams and targets add an exciting new dimension to Drell-Yan scattering. In particular, the two initial-state hadrons give Drell-Yan sensitivity to chirally-odd transversity distributions.Comment: 23 pages, 9 figures, to appear in J. Phys. G, resubmission corrects typographical error

Tracing the origin of the single-spin asymmetries observed in inclusive hadron production processes at high energies

It is pointed out that the existing models for the left-right asymmetries observed in single-spin inclusive hadron production processes can be differentiated experimentally. Several such experiments are proposed with which the basic assumptions of these models can be tested individually.Comment: 12 pages, one figur

OPTICS AND FIELD ERROR COMPENSATION IN THE FNAL PERMANENT MAGNET 8.9 GEV/C PROTON TRANSFER LINE

Abstract Protons are transported 760 m from the Booster extraction point to injection into the Fermilab Main Injector. Apart from two, comparatively short, specialized optical matching sections the transfer lattice is described by 90 o betatron phase advance arc cells and missing-dipole dispersion suppressing cells. This repetative structure, combined with the small average bend per cell makes it feasible to construct this section exclusively from lowfield permanent dipoles and gradient magnets. The permanent magnet section is nearly devoid of powered correctors: trajectory control and momentum error compensation is accomplished instead by moving select gradient magnets transversely. Permanent magnets are being used in the transfer line primarily to acquire the manufacturing and operational experience necessary to ensure success of the future FNAL Recycler Ring