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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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DOE OSTI2011

The Impact of LUNA Results on Astroparticle Physics

LUNA (Laboratory for Underground Nuclear Astrophysics) is devoted to measure nuclear cross sections relevant in astroparticle physics. The facility operates underground, at the 'Laboratori Nazionali del Gran Sasso'(LNGS), where the cosmic ray induced background is very low. The LUNA measurements are important in neutrino physics, in the study of the Sun and other celestial bodies, in the Big Bang Nucleosynthesis.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

The performance of the LHCf detector

The LHCf experiment is designed to measure energies and transverse momenta of neutral particles emitted in the forward region of {radical}(s) = 14 TeV p-p collision at {+-}140 m away from the interaction point1 (IP1) of LHC. The energy resolution is confirm to be within 5% and the position resolution is better than 0.2 mm for gamma-rays with energies from 100 GeV to 200 GeV by the test beam results at the CERN-SPS. LHCf has taken data at 2009 and 2010 at {radical}(s) = 900 GeV and 7 TeV collision. A brief summary of LHCf operation at LHC is also reported here.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2011

Experimental Status of the Longitudinal Structure Function, F{sub L}

The current experimental status of the longitudinal structure structure function is discussed. In particular, recent measurements from the JLab Hall C program on proton, deuteron, and nuclei, which cover a range from moderate to large Bjorken x and 0.1 < Q{sup 2} < 4 (GeV/c){sup 2} are discussed.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Strangeness Production at COSY

The paper gives an overview of strangeness-production experiments at the Cooler Synchrotron COSY. Results on kaon-pair and {phi} meson production in pp, pd and dd collisions, hyperon-production experiments and {Lambda}p final-state interaction studies are presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Recent Results from the WASA-at-COSY Experiment

Studies of light meson decays are the key experiments for the WASA detector at COSY-Juelich. One of the world largest data samples of the {eta} meson decays have been recently collected in the pd {yields}{sup 3}He{eta} and in the pp {yields} pp{eta} reactions. The status of the analysis of various decay channels and the further plans for the light meson decay program are presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Highlights from RHIC Spin Physics Program

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory delivers the world's highest energy polarized proton-proton collisions at a center of mass energy up to 500 GeV and provides a unique opportunity to study the quark and gluon spin structure of the proton and QCD dynamics at high energy scale. RHIC has produced many exiting physics results in recent years. The latest data from RHIC significantly constrain the gluon spin contribution to the proton spin, and the parity violating single spin asymmetry are observed for the first time in W production by both the PHENIX and STAR collaborations. In this report, I present the latest results from the PHENIX and STAR experiments, followed by a brief discussion of the future prospects of transverse physics, particularly on the importance of the unique measurements of Drell-Yan single spin asymmetry.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Measurement of the transition form factor of {eta} meson with WASA-at-COSY

Reaction {eta}{yields}e{sup +}e{sup -}{gamma} is used to investigate the transition form factor of {eta} meson with WASA detector at COSY. Where the {eta} meson is produced in pp collision at 1.4 GeV. We present the analysis techniques and preliminary results of {eta} Dalitz decays.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Experimental study of pp{eta} dynamics with WASA-at-COSY

To investigate the interaction of {eta}-meson with the nucleons, its production, near the kinematical threshold, in proton-proton collisions has been studied with the WASA detector at COSY storage ring in Juelich, Germany. The data has been taken at beam energy 1400 MeV (corresponding to excess energy (Q = 57 MeV). The {eta}-meson was detected via its 3{pi}{sup 0} decay in nearly 4{pi} detector and two protons were measured in forward direction. The determination of four vectors of both protons and the {eta}-meson in the final state allowed to derive complete kinematical information of the pp{eta}-system. The analysis resulted in 9x10{sup 6} events of {eta}{yields}3{pi}{sup 0} giving total production cross-section (8.87{+-}0.03{sub stat}{+-}2.57{sub sys}){mu}b. The angular distribution of {eta}-meson in the center of mass frame is anisotropic and squared invariant mass distributions for proton-proton and proton-{eta} shows deviation from pure phase space.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Physics at COSY-Juelich

COSY, a storage and cooler synchrotron, which is fed by an injector cyclotron, is operated at Forschungszentrum Juelich (Germany). It provides phase space cooled polarized or unpolarized beams of protons and deuterons with momenta between 0.3 and 3.7 GeV/c for internal experiments and to external target stations. The major experimental facilities, used for the ongoing physics program, are ANKE and WASA (internal) and TOF (external). A new internal target station to investigate polarization build-up by spin-filtering (PAX) has recently been commissioned. COSY is the machine for hadron spin physics on a world-wide scale, which is also used for tests in conjunction with plans to build a dedicated storage ring for electric dipole moment (EDM) measurements of proton, deuteron and {sup 3}He. In this contribution recent results as well as future plans are summarized.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Vacuum Properties of the {Sigma}(1385){sup +} Resonance

We present data taken employing a proton beam incident on a liquid hydrogen target with a kinetic energy of 3.5 GeV. A total statistics of {approx_equal} 1.2.10{sup 9} events was collected by the High Acceptance Di-Electron Spectrometer (HADES) and analysed to study the properties of the {Sigma}(1385){sup +}-resonance. A clear signal corresponding to a peak of the Breit-Wigner parametrization of M = 1382.98{+-}0.79MeV/c{sup 2} and a width of {Gamma}{sub 0} = 38.78{+-}2.03 MeV/c{sup 2} was extracted. The investigation of the differential production cross- section shows a strong anisotropy in the angular distribution of the {Sigma}(1385){sup +}-hyperon with respect to the beam direction in p+p collisions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

N* production from pp and p-barp collisions

With an effective Lagrangian approach, we give a full analysis on the NN{yields}NN{pi}{pi} and pp{yields}pn{pi}{sup +} reactions for proton beam energy from 1 to 1.5 GeV. The results are very consistent with the experiment data from CELSIUS, KEK, COSY, and so on. Based on these results, we consider the N-barN{yields}N-barN{pi}{pi} and p-barp{yields}p-barn{pi}{sup +} for proton beam energy up to 4 GeV. Compare to the pp collisions, there are many benefits to study N* resonances in these two reactions. And for the high proton beam energy up to 15 GeV, we consider some new resonances with hidden charm which are definitely beyond three constituent quarks model in the p-barp{yields}p-barpJ/{psi} and p-barp{yields}p-barp{eta}{sub c}, where there are very nice places to find these new N{sub cc}-bar*. The predicted results about p-barp collisions can be looked for at the forthcoming PANDA/FAIR experiments.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

pp{yields}p{Lambda}K{sup +} reaction in search for the K{sup -}pp state - quest for a kaonic nuclei

The dibaryonic kaonic nuclear bound state, K{sup -}pp is searched by studying an exclusive p+p{yields}p+{Lambda}+K{sup +} process at several beam energies. A signature of the K{sup -}pp is explored in a p+p{yields}X({identical_to}K{sup -}pp)+K{sup +} reaction that follows a decay of the X into p+{Lambda}. We found in a missing-mass {Delta}M(K{sup +}) spectrum and a {Lambda}p invariant-mass M({Lambda}p) spectrum of DISTO data at 2.85 GeV a resonance with M = 2267 MeV/c{sup 2} and {Gamma} = 118 MeV. Those events are found to be associated with a mono energetic kaon. We investigate this resonance as a candidate of the K{sup -}pp further also with a different beam energies.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

The Hyperon {Lambda}(1405) in p+p reactions

We present an analysis of the hyperon {Lambda}(1405) for p+p reactions at 3.5 GeV kinetic beam energy. The data were taken with the High Acceptance Di-Electron Spectrometer (HADES). A {Lambda}(1405) signal could be reconstructed in both charged decay channels ({Lambda}(1405){yields}{Sigma}{sup {+-}}{pi}{sup {+-}}).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Fermilab E906/SeaQuest Drell-Yan Experiment

The E906/SeaQuest experiment will use the 120 GeV proton beam extracted from the Fermilab Main Injector to measure the Drell-Yan cross section in p-p, p-d, and p-A scattering. Data from liquid hydrogen and deuterium targets will be sensitive to the light anti-quark asymmetry, d-bar/u-bar, over a range of parton momentum fraction 0.04<x<0.45. Previous measurements from the E866/NuSea experiment have shown that while there were clear signs of flavor asymmetry at moderate x, the quark sea became flavor symmetric at higher x, suggesting a possible shift in the underlying mechanism generating the sea. Measurements from solid nuclear targets (carbon, calcium, and tungsten) will determine the modification of antiquark distributions in the nucleus. The results, in addition to being complementary to similar measurements performed through deep inelastic scattering, will also be valuable in providing the nuclear corrections necessary to extract nucleon parton distribution functions from neutrino data. The experiment will start in 2011, and will run for two years.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

{Delta}G and {Delta}q-bar measurements at PHENIX

RHIC provides a unique opportunity to address the components of the proton spin. In comparison to deep inelastic scattering experiments, the gluon is the main player in proton-proton collisions. PHENIX has measured double spin asymmetries of various processes. Those contain the information of the gluon spin component ({Delta}G). In addition high energy collisions open the unique channel to access flavor dependent information of quark polarization through the real W boson production. Because of the feature of weak interaction, the parity violating process defines the helicity of quarks in the interaction. The single spin asymmetry is the observable. It is especially interesting to probe anti-quark components ({Delta}q-bar). In this article, we report the recent progress of {Delta}G and {Delta}q-bar measurements at PHENIX.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Probing multigluon correlations through single spin asymmetries in pp collisions

We study the single spin asymmetries for the D-meson production, Drell-Yan lepton-pair production and the direct-photon production in the pp collision induced by the twist-3 three-gluon correlation functions in the transversely polarized nucleon. We present a corresponding polarized cross section formula in the leading-order with respect to the QCD coupling and a model calculation for the asymmetries, illustrating the sensitivity to the form of the correlation functions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Sea Quark Polarization Measurement Via W-Boson in Forward Rapidity at PHENIX

The Relativistic Heavy Ion Collider (RHIC) at BNL provides a unique opportunity to collide polarized protons. One of the hightlight of the spin program at {radical}(s) = 500 GeV is the direct measurement of sea quark contribution to the proton spin via W-boson production by measuring parity violating single spin asymmetry. A new trigger on forward muons in PHENIX identiienAoes and triggers on high momentum Ws suppressing a large number of low momentum muons coming from hadronic decays. Since the original muon trigger will fire on any muon above {approx}2 GeV/c, it will not provide the required rejection factor for 500 GeV running, which is about 4500. New fast readout trigger electronics and timing device were developed and installed to existing muon detection system in PHENIX. The performance of the new muon trigger and the fast turnaround offline analysis result from the first {radical}(s) = 500 GeV production run (Run11) will be discussed.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

Searches for BSM and Higgs boson at LHC

This article reviews the recent results from the two energy frontier experiments, ATLAS and CMS at the large hadron collider (LHC), using the data collected during 2011 corresponding up to 4.9 fb{sup -1} integrated luminosity of {radical}(s) = 7TeV proton proton collisions. The recent results of searches for the Standard Model Higgs boson, and searches for beyond Standard Model physics based on supersymmetry and other new exotic models are presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗