Contribution of exclusive diffractive processes to the measured azimuthal asymmetries in SIDIS

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F20%3A00532580" target="_blank" >RIV/68081731:_____/20:00532580 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21340/20:00344586 RIV/46747885:24510/20:00008685 RIV/00216208:11320/20:10414864

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0550321320301255" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0550321320301255</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.nuclphysa.2020.115039" target="_blank" >10.1016/j.nuclphysa.2020.115039</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Contribution of exclusive diffractive processes to the measured azimuthal asymmetries in SIDIS

Popis výsledku v původním jazyce

Hadron leptoproduction in Semi-Inclusive measurements of Deep-Inelastic Scattering (SIDIS) on unpolarised nucleons allows one to get information on the intrinsic transverse momentum of quarks in a nucleon and on the Boer-Mulders function through the measurement of azimuthal modulations in the cross section. These modulations were recently measured by the HERMES experiment at DESY on proton and deuteron targets, and by the COMPASS experiment using the CERN SPS muon beam and a (LiD)-Li-6 target. In both cases, the amplitudes of the cos phi(h) and cos 2 phi(h) modulations show strong kinematic dependences for both positive and negative hadrons. It has been known since some time that the measured final-state hadrons in those SIDIS experiments receive a contribution from exclusive diffractive production of vector mesons, particularly important at large values of z, the fraction of the virtual photon energy carried by the hadron. In previous measurements of azimuthal asymmetries this contribution was not taken into account, because it was not known that it could distort the azimuthal modulations. Presently, a method to evaluate the contribution of the exclusive reactions to the azimuthal asymmetries measured by COMPASS has been developed. The subtraction of this contribution results in a better understanding of the kinematic effects, and the remaining non-zero cos 2 phi(h) modulation gives indication for a non-zero Boer-Mulders effect.

Název v anglickém jazyce

Contribution of exclusive diffractive processes to the measured azimuthal asymmetries in SIDIS

Popis výsledku anglicky

Hadron leptoproduction in Semi-Inclusive measurements of Deep-Inelastic Scattering (SIDIS) on unpolarised nucleons allows one to get information on the intrinsic transverse momentum of quarks in a nucleon and on the Boer-Mulders function through the measurement of azimuthal modulations in the cross section. These modulations were recently measured by the HERMES experiment at DESY on proton and deuteron targets, and by the COMPASS experiment using the CERN SPS muon beam and a (LiD)-Li-6 target. In both cases, the amplitudes of the cos phi(h) and cos 2 phi(h) modulations show strong kinematic dependences for both positive and negative hadrons. It has been known since some time that the measured final-state hadrons in those SIDIS experiments receive a contribution from exclusive diffractive production of vector mesons, particularly important at large values of z, the fraction of the virtual photon energy carried by the hadron. In previous measurements of azimuthal asymmetries this contribution was not taken into account, because it was not known that it could distort the azimuthal modulations. Presently, a method to evaluate the contribution of the exclusive reactions to the azimuthal asymmetries measured by COMPASS has been developed. The subtraction of this contribution results in a better understanding of the kinematic effects, and the remaining non-zero cos 2 phi(h) modulation gives indication for a non-zero Boer-Mulders effect.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Nuclear Physics. B

ISSN

0550-3213

e-ISSN

—

Svazek periodika

956

Číslo periodika v rámci svazku

JUL

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

14

Strana od-do

115039

Kód UT WoS článku

000540262200008

EID výsledku v databázi Scopus

2-s2.0-85084360936