Azimuthal asymmetries in production of charged hadrons by high energy muons off polarized deuterons at COMPASS.

Successful realization of polarized Drell-Yan physics program is one of the main goals of the second stage of the COMPASS experiment. Drell-Yan measurements with high energy (190 GeV/c) pion beam and transversely polarized NH3 target have been initiated by a pilot-run in the October 2014 and will be followed by 140 days of data taking in 2015. In the past twelve years COMPASS experiment performed series of SIDIS measurements with high energy muon beam and transversely polarized deuteron and proton targets. Results obtained for Sivers effect and other target transverse spin dependent and unpolarized azimuthal asymmetries in SIDIS serve as an important input for general understanding of spin-structure of the nucleon and are being used in numerous theoretical and phenomenological studies being carried out in the field of transvers-spin physics. Measurement of the Sivers and all other azimuthal effects in polarized Drell-Yan at COMPASS will reveal another side of the spin-puzzle providing a link between SIDIS and Drell-Yan branches. This will be a unique possibility to test universality and key-features of transverse momentum dependent distribution functions (TMD PDFs) using essentially same experimental setup and exploring same kinematic domain. In this review main physics aspects of future COMPASS polarized Drell-Yan measurement of azimuthal transverse spin asymmetries will be presented, giving a particular emphasis on the link with very recent COMPASS results obtained for SIDIS transverse spin asymmetries from four ”Drell-Yan” [Formula: see text]-ranges.

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High Energy Polarized Deuterons at the Argonne National Laboratory Zero Gradient Synchrotron

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1979.4329983 ◽

1979 ◽

Vol 26 (3) ◽

pp. 3200-3202 ◽

Cited By ~ 4

Author(s):

Everette F. Parker ◽

Fred E. Brandeberry ◽

Edwin A. Crosbie ◽

Martin J. Knott ◽

Charles W. Potts ◽

...

Keyword(s):

National Laboratory ◽

Argonne National Laboratory ◽

High Energy ◽

Polarized Deuterons

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Overview of TMD Evolution

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194516600144 ◽

2016 ◽

Vol 40 ◽

pp. 1660014 ◽

Cited By ~ 1

Author(s):

Daniël Boer

Keyword(s):

Transverse Momentum ◽

Momentum Distribution ◽

High Energy ◽

Transverse Momentum Distribution ◽

Parton Distributions ◽

Transverse Momentum Dependent ◽

Azimuthal Asymmetries

Transverse momentum dependent parton distributions (TMDs) appear in many scattering processes at high energy, from the semi-inclusive DIS experiments at a few GeV to the Higgs transverse momentum distribution at the LHC. Predictions for TMD observables crucially depend on TMD factorization, which in turn determines the TMD evolution of the observables with energy. In this contribution to SPIN2014 TMD factorization is outlined, including a discussion of the treatment of the nonperturbative region, followed by a summary of results on TMD evolution, mostly applied to azimuthal asymmetries.

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