A Gas Target Internal to the LHC for the Study of pp Single-Spin Asymmetries and Heavy Ion Collisions

We discuss the application of an open storage cell as gas target for a proposed LHC fixed-target experiment AFTER@LHC. The target provides a high areal density at minimum gas input, which may be polarized1H,2H, or3He gas or heavy inert gases in a wide mass range. For the study of single-spin asymmetries in pp interaction, luminosities of nearly 1033/cm2 s can be produced with existing techniques.

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Transverse Single-Spin Asymmetries in Proton-Proton Collisions Within Collinear Factorization

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194515600332 ◽

2015 ◽

Vol 37 ◽

pp. 1560033

Author(s):

Daniel Pitonyak ◽

Koichi Kanazawa ◽

Yuji Koike ◽

Andreas Metz

Keyword(s):

Transverse Momentum ◽

Heavy Ion ◽

High Transverse Momentum ◽

Relativistic Heavy Ion Collider ◽

Collinear Factorization ◽

Transverse Momentum Dependent ◽

Spin Asymmetries ◽

Single Spin ◽

Single Spin Asymmetries ◽

Azimuthal Asymmetries

We provide a new analysis within collinear factorization of transverse single-spin asymmetries (TSSAs) in high transverse momentum charged and neutral pion production in pp collisions at the Relativistic Heavy Ion Collider (RHIC). This study incorporates the so-called twist-3 fragmentation term and shows that one can describe RHIC data through this mechanism. Moreover, by fixing other non-perturbative inputs through extractions of transverse momentum dependent functions in e+e- → h1h2X and semi-inclusive deep-inelastic scattering (SIDIS), we provide for the first time a consistency between certain spin/azimuthal asymmetries in all three reactions (i.e., pp, e+e-, and SIDIS).

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Azimuthal Single-Spin Asymmetries of Charged Pions in Jets in s = 200 GeV p↑p Collisions at STAR

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194516600405 ◽

2016 ◽

Vol 40 ◽

pp. 1660040 ◽

Cited By ~ 7

Author(s):

J. Kevin Adkins ◽

James L. Drachenberg

Keyword(s):

Spin Asymmetry ◽

Heavy Ion ◽

Relativistic Heavy Ion Collider ◽

Spin Asymmetries ◽

Proton Collisions ◽

Single Spin ◽

Single Spin Asymmetries ◽

Polarized Proton ◽

Charged Pions ◽

200 Gev

Single spin asymmetry measurements ([Formula: see text]) of the azimuthal distribution of charged pions inside jets produced in transversely polarized proton collisions are sensitive to the transversity distribution and the Collins fragmentation function. The STAR Detector at the Relativistic Heavy Ion Collider is well suited for these types of measurements as it is capable of full jet reconstruction and charged pion identification in the mid-rapidity region ([Formula: see text][Formula: see text][Formula: see text][Formula: see text]). We report here the first observation of Collins [Formula: see text] asymmetries in [Formula: see text] GeV [Formula: see text] collisions.

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Transverse Single-Spin Asymmetries in Proton-Proton Collisions at the AFTER@LHC Experiment in a TMD Factorisation Scheme

Advances in High Energy Physics ◽

10.1155/2015/475040 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 10

Author(s):

M. Anselmino ◽

U. D’Alesio ◽

S. Melis

Keyword(s):

Spin Asymmetry ◽

Parton Model ◽

Fixed Target ◽

Proton Proton ◽

Spin Asymmetries ◽

Proton Collisions ◽

Single Spin ◽

Single Spin Asymmetries ◽

Target Experiment ◽

Proton Proton Collisions

The inclusive large-pTproduction of a single pion, jet or direct photon, and Drell-Yan processes, are considered for proton-proton collisions in the kinematical range expected for the fixed-target experiment AFTER, proposed at LHC. For all these processes, predictions are given for the transverse single-spin asymmetry,AN, computed according to a Generalised Parton Model previously discussed in the literature and based on TMD factorisation. Comparisons with the results of a collinear twist-3 approach, recently presented, are made and discussed.

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TRANSVERSE SPIN AND TRANSVERSE MOMENTUM EFFECTS AT COMPASS

Modern Physics Letters A ◽

10.1142/s0217732309001224 ◽

2009 ◽

Vol 24 (35n37) ◽

pp. 3015-3024 ◽

Cited By ~ 5

Author(s):

FRANCO BRADAMANTE

Keyword(s):

Transverse Momentum ◽

Muon Beam ◽

Transverse Spin ◽

Fixed Target ◽

Deuteron Target ◽

Spin Asymmetries ◽

Single Spin ◽

Polarized Target ◽

Single Spin Asymmetries ◽

Target Experiment

The study of transverse spin and transverse momentum effects is part of the scientific program of COMPASS, a fixed target experiment at the CERN SPS. For these studies, a 160 GeV/c momentum muon beam is scattered on a transversely polarized nucleon target, and the scattered muon and the forward going hadrons produced in DIS processes are reconstructed and identified in a magnetic spectrometer. The measurements have been performed on a deuteron target in 2002, 2003 and 2004, and on a proton target in 2007. The main results obtained measuring single spin asymmetries are reviewed, with particular emphasis on the most recent proton measurements. After two years of spectroscopy measurements with hadron beams, in 2008 and 2009, the Collaboration will resume measurements with the muon beam and a transversely polarized target in 2010.

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Transverse Single-Spin Asymmetries in Proton-Proton Collisions at the AFTER@LHC Experiment

Advances in High Energy Physics ◽

10.1155/2015/257934 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

K. Kanazawa ◽

Y. Koike ◽

A. Metz ◽

D. Pitonyak

Keyword(s):

Hadron Collider ◽

Proton Proton ◽

Spin Asymmetries ◽

Proton Collisions ◽

Single Spin ◽

Single Spin Asymmetries ◽

Direct Photon Production ◽

Target Experiment ◽

Analytical Formulas ◽

Proton Proton Collisions

We present results for transverse single-spin asymmetries in proton-proton collisions at kinematics relevant for AFTER, a proposed fixed-target experiment at the Large Hadron Collider. These include predictions for pion, jet, and direct photon production from analytical formulas already available in the literature. We also discuss specific measurements that will benefit from the higher luminosity of AFTER, which could help resolve an almost 40-year puzzle of what causes transverse single-spin asymmetries in proton-proton collisions.

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