Recent results and prospects for high p T physics at DØ

The European Physical Journal C - I present recent results from the DØ experiment using ≈ 50 pb–1 of data recorded at the center of mass energy of 1.96 TeV at the Fermilab...     

Recent results from PHOBOS on particle production at high p T

A selection of experimental results from the PHOBOS Collaboration relevant for probing high-energy nuclear collisions with high transverse momentum particles is presented. The inclusive yields of charged particles and comparisons between nuclear and elementary collisions already reveal a large amount of parton energy loss in the hot and dense medium created in heavy ion collisions. Remarkable scaling and factorization features are observed, unifying the data taken at various collision energies, centralities and nuclear sizes. To further analyze the nature of the energy loss, a measurement of pseudorapidity (Δη) and azimuthal angle (Δφ) correlations between high transverse momentum charged hadrons (p _T >2.5 GeV/c) and all associated charged particles is presented at both short-range (small Δη) and long-range (large Δη) over a continuous detector acceptance covering −4<Δη<2. Various near- and away-side features of the correlation structure are discussed as a function of centrality in Au + Au collisions at  GeV. The results provide new information about the longitudinal (Δη) extent of the near-side ‘ridge’ structure, first observed by the STAR Collaboration over a narrower η range. In central Au + Au collisions the ridge structure extends to at least Δη=4, and its strength completely diminishes as collisions become more peripheral. Presenter of the paper on the 3rd International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions, 8–14 June 2008, Illa da Toxa (Galicia-Spain).     

Recent results on heavy-ion physics from the SPS

The CERN SPS heavy-ion physics program was recently given an important and fresh impetus with the running of the NA60 dimuon experiment, which probed indium-indium collisions at 158 GeV per incident nucleon (in 2003), as well as proton-nucleus collisions at 158 and 400 GeV (essentially in 2004). Several interesting physics results have been obtained and were recently presented by NA60. They address such varied physics topics as the search for in-medium modifications on the ρ short-lived vector meson (which could be related to the restoration of chiral symmetry, spontaneously broken in the hadronic world), the understanding of the “anomalous” J/ψ suppression (expected to be a signature of quark-gluon deconfinement), the search for thermal dimuons (presumably radiated from a thermal system, maybe composed of deconfined quarks and gluons — the “quark-gluon plasma”), the understanding of the enhancement of θ production in heavy-ion collisions, etc. These topics were previously studied by other SPS experiments, and very interesting observations were made, but serious doubts remained concerning the interpretation of those earlier results. It is remarkable that one single experiment, NA60, is able to provide high-quality information on each of these many topics, potentially triggering a very significant step forward in our understanding of “quark-matter physics”.In this paper, after a general introduction, I describe the NA60 apparatus, the data taking conditions, and the main steps in the data reconstruction procedure. I then give some information on the muon track matching and background subtraction procedures. In the remaining sections I review some of the results presently available from the on-going physics analyses, in what concerns the studies of low mass and intermediate mass dimuon production, and J/ψ suppression, in proton-nucleus and indium-indium collisions. These new (and still preliminary) results are placed in perspective, by recalling the findings of previous experiments.     

Recent developments in high energy physics

Recent results from experiments with solar, atmospheric and accelerator neutrinos are presented. Some of the important results from the LEP and TEVATRON colliders are summarised.     

Recent KLOE results on hadron physics

The KLOE experiment at the Frascati e ⁺ e ^- collider DAFNE has completed this year its data taking. An integrated luminosity of 2.7fb^-1 has been collected mostly at the φ-resonance peak. A wide experimental program is in progress. The detection of φ radiative decays allows to study the properties of the lowest-mass scalar and pseudoscalar mesons and to obtain information on their structure. The main results are reviewed together with the prospects for low-energy e ⁺ e ^- physics at Frascati.     

Search for new physics in high pT like-sign dilepton events at CDF II

We present a search for new physics in events with two high pT leptons of the same electric charge, using data with an integrated luminosity of 6.1 fb(-1). The observed data are consistent with standard model predictions. We set 95% C.L. lower limits on the mass of doubly charged scalars decaying to like-sign dileptons, m(H±±) > 190-245 GeV/c(2), assuming 100% BR to ee, μμ or eμ.     

Recent neutrino oscillation results from T2K

The Tokai-to-Kamioka (T2K) experiment studies neutrino oscillations in a ~600 MeV muon neutrino beam sent at 295 km from the Japan Proton Accelerator Complex (J-PARC) to the Super Kamiokande (SK) detector in Kamioka. The primary goals of T2K are to search for the appearance of electron neutrinos at SK resulting from ?? ₁₃?>?0 and to precisely measure ?? ₂₃ and $\Delta m^2_{32}$ via ?? _?? disappearance. We report on T2K results obtained from neutrino data taken in 2010 and 2011.     

Quasi-model-independent search for new high p(T) physics at D0

We apply a quasi-model-independent strategy ("Sleuth") to search for new high p(T) physics in approximately 100 pb(-1) of pp collisions at square root of (s) = 1.8 TeV collected by the D0 experiment during 1992-1996 at the Fermilab Tevatron. We systematically analyze many exclusive final states and demonstrate sensitivity to a variety of models predicting new phenomena at the electroweak scale. No evidence of new high p(T) physics is observed.     

Beauty and charm physics at CDF Run II

The European Physical Journal C - Using the data samples collected with the CDF Run II detector during the year 2002 and early 2003, new measurements of the production cross-sections and the...     

Recent high-p_{\rm T} results from STAR

The STAR Collaboration has a broad range of recent results on intermediate and high- phenomena in Au + Au collisions at = 200 and 62 GeV and in d + Au at = 200 GeV. These include new measurements of spectra, azimuthal anisotropies and di-hadron correlations. The comparison of the 62 and 200 GeV Au + Au results indicates that jet quenching, elliptic flow and di-hadron correlation measurements are very similar at the two energies. Meson-baryon differences that have been seen at intermediate in 200 GeV Au + Au collisions are also present in 62 GeV Au + Au collisions and in 200 GeV d + Au collisions. Measurements of backward-forward inclusive hadron yield asymmetries and forward-midrapidity di-hadron correlations in d + Au collisions are consistent with the saturation picture. A brief review of these results is presented. Arrival of the final proofs: 30 June 2005 PACS: 25.75.Dw, 25.75.Ld, 25.75.Gz     

Tau physics results from BABAR

Since 1999, the BABAR collaboration has accumulated and studied large samples of tau lepton pairs. The main physics results are reported.     

Tau physics results from BABAR

Since 1999, the BABAR collaboration has accumulated and studied large samples of tau lepton pairs. The main physics results are reported.     

Recent results from LEPS

Photoproduction of baryons with strangeness,such as the Σ（1385）,Λ（1520） and possibly the Θ ＋,are described from measurements at the LEPS/SPring-8 facility in Japan.Linearly polarized photons in the energy range of 1.5–2.4 GeV,along with the forward-angle kinematics at LEPS,provide unique data to learn about these baryons,which are non-perturbative solutions of QCD.     

Recent results from HERA

After the end of data taking in 2007, the experiments H1 and ZEUS have entered into an intense phase of data analysis. Recent results of this effort on neutral (NC) and charged current (CC) cross sections at high Q2, the longitudinal structure function Fl, inclusive diffraction, heavy flavour production and on searches for glueballs are presented. Also shown are results of a combined analysis on inclusive NC and CC cross sections performed by H1 and ZEUS using HERA-I data.     

Recent results from PHOBOS

The PHOBOS Collaboration has measured charged particles emitted over the range ?5.4<η<5.4 for Au+Au collisions at energies of $\sqrt {s_{NN} } = 19.6$ , 62.4, 130 and 200 GeV. In this contribution I will present recent results on the pseudorapidity distributions, total charged-particle production, and collective flow of particles obtained from these measurements.     

Recent results from PHOBOS

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has delivered the collisions between Au nuclei at the highest center of mass energies achieved in the laboratory to date. PHOBOS is one of four experiments studying the these interactions. In this paper we will briefly describe the PHOBOS experiment, and discuss some of the current physics results obtained at $\sqrt {s_{NN} } = 56$ , 130 and 200 GeV: the systematic study of charged particle multiplicity as a function of pseudorapidity and centrality, measurements of antiparticle to particle ratios, and the hadron spectra as function of transverse momentum for both high and low pt.     

Recent results from LEPS

Photoproduction of baryons with strangeness,such as the Σ(1385),Λ(1520) and possibly the Θ +,are described from measurements at the LEPS/SPring-8 facility in Japan.Linearly polarized photons in the energy range of 1.5–2.4 GeV,along with the forward-angle kinematics at LEPS,provide unique data to learn about these baryons,which are non-perturbative solutions of QCD.