Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrts_{NN}=200 GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among ...these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
The LHCf experiment aims to improve knowledge of forward neutral particle production spectra at the LHC energy which is relevant for the interpretation of air shower development of high energy cosmic ...rays. Two detectors, each composed of a pair of sampling and imaging calorimeters, have been installed at the forward region of IP1 to measure
π
0 energy spectra above 600
GeV. In this paper, we present a Monte Carlo study of the
π
0 measurements to be performed with one of the LHCf detectors for proton–proton collisions at
s
=
14
TeV. In approximately 40
min of operation at luminosity
0.8
×
10
29
cm
-
2
s
-
1
during the beam commissioning phase of LHC, about 1.5
×
10
4
π
0 events are expected to be obtained at two transverse positions of the detector. The backgrounds from interactions of secondary particles with beam pipes and interactions of beam particles with residual gas in the beam pipes are expected to be less than 0.1% of the signal from
π
0s. We also discuss the capability of LHCf measurements to discriminate between the various hadron interaction models that are used for simulation of high energy air showers, such as DPMJET3.03, QGSJETII-03, SIBYLL2.1 and EPOS1.99.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We have searched for proton decays via p{yields}e{sup +}{pi}{sup 0} and p{yields}{mu}{sup +}{pi}{sup 0} using data from a 91.7 kt{center_dot}yr exposure of Super-Kamiokande-I and a 49.2 ...kt{center_dot}yr exposure of Super-Kamiokande-II. No candidate events were observed with expected backgrounds induced by atmospheric neutrinos of 0.3 events for each decay mode. From these results, we set lower limits on the partial lifetime of 8.2x10{sup 33} and 6.6x10{sup 33} years at 90% confidence level for p{yields}e{sup +}{pi}{sup 0} and p{yields}{mu}{sup +}{pi}{sup 0} modes, respectively.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The LHCf experiment is a CERN experiment dedicated to forward physics which is optimized to measure the neutral particle flow at extreme pseudo-rapidity values, ranging from 8.4 up to infinity. LHCf ...results are extremely important for the calibration of the hadronic interaction models used for the study of the development of atmospheric showers in the Earth atmosphere. Starting from the recent run of proton-Lead nucleus interactions at LHC, the LHCf and ATLAS collaborations have performed a common data taking which allows a combined study of the central and forward regions of the interaction. The latest results of LHCf, the upgrade of the detectors for the next 6.5 TeV + 6.5 TeV proton–proton run and the status of the LHCf-ATLAS common activities are summarized in this paper.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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