Comparison of transverse single-spin asymmetries for forward pi(0) production in polarized pp, pAl and pAu collisions at nucleon pair c.m. energy root s(NN)=200 GeV

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F21%3A00542666" target="_blank" >RIV/61389005:_____/21:00542666 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21340/21:00351229

Výsledek na webu

<a href="https://doi.org/10.1103/PhysRevD.103.072005" target="_blank" >https://doi.org/10.1103/PhysRevD.103.072005</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevD.103.072005" target="_blank" >10.1103/PhysRevD.103.072005</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Comparison of transverse single-spin asymmetries for forward pi(0) production in polarized pp, pAl and pAu collisions at nucleon pair c.m. energy root s(NN)=200 GeV

Popis výsledku v původním jazyce

The STAR collaboration reports a measurement of the transverse single-spin asymmetries, A(N), for neutral pions produced in polarized proton collisions with protons (pp), with aluminum nuclei (pAl) and with gold nuclei (pAu) at a nucleon-nucleon center-of-mass energy of 200 GeV. Neutral pions are observed in the forward direction relative to the transversely polarized proton beam, in the pseudorapidity region 2.7 < eta < 3.8. Results are presented for pi(0)s observed in the STAR forward meson spectrometer electromagnetic calorimeter in narrow Feynman x (x(F)) and transverse momentum (p(T)) bins, spanning the range 0.17 < x(F) < 0.81 and 1.7 < p(T) < 6.0 GeV/c. For fixed x(F) < 0.47, the asymmetries are found to rise with increasing transverse momentum. For larger x(F), the asymmetry flattens or falls as p(T) increases. Parametrizing the ratio r(A) = A(N)(pA)/A(N)(pp) = A(P) over the kinematic range, the ratio r(A) is found to depend only weakly on A, with < P > = -0.027 +/- 0.005. No significant difference in P is observed between the low-p(T) region, p(T) < 2.5 GeV/c, where gluon saturation effects may play a role, and the high-p(T) region, p(T) > 2.5 GeV/c. It is further observed that the value of A(N) is significantly larger for events with a large-p(T) isolated pi(0) than for events with a nonisolated pi(0) accompanied by additional jetlike fragments. The nuclear dependence r(A) is similar for isolated and nonisolated pi(0) events.

Název v anglickém jazyce

Comparison of transverse single-spin asymmetries for forward pi(0) production in polarized pp, pAl and pAu collisions at nucleon pair c.m. energy root s(NN)=200 GeV

Popis výsledku anglicky

The STAR collaboration reports a measurement of the transverse single-spin asymmetries, A(N), for neutral pions produced in polarized proton collisions with protons (pp), with aluminum nuclei (pAl) and with gold nuclei (pAu) at a nucleon-nucleon center-of-mass energy of 200 GeV. Neutral pions are observed in the forward direction relative to the transversely polarized proton beam, in the pseudorapidity region 2.7 < eta < 3.8. Results are presented for pi(0)s observed in the STAR forward meson spectrometer electromagnetic calorimeter in narrow Feynman x (x(F)) and transverse momentum (p(T)) bins, spanning the range 0.17 < x(F) < 0.81 and 1.7 < p(T) < 6.0 GeV/c. For fixed x(F) < 0.47, the asymmetries are found to rise with increasing transverse momentum. For larger x(F), the asymmetry flattens or falls as p(T) increases. Parametrizing the ratio r(A) = A(N)(pA)/A(N)(pp) = A(P) over the kinematic range, the ratio r(A) is found to depend only weakly on A, with < P > = -0.027 +/- 0.005. No significant difference in P is observed between the low-p(T) region, p(T) < 2.5 GeV/c, where gluon saturation effects may play a role, and the high-p(T) region, p(T) > 2.5 GeV/c. It is further observed that the value of A(N) is significantly larger for events with a large-p(T) isolated pi(0) than for events with a nonisolated pi(0) accompanied by additional jetlike fragments. The nuclear dependence r(A) is similar for isolated and nonisolated pi(0) events.

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

2021

Kód důvěrnosti údajů

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

Název periodika

Physical Review D

ISSN

2470-0010

e-ISSN

2470-0029

Svazek periodika

103

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

20

Strana od-do

072005

Kód UT WoS článku

000648577400001

EID výsledku v databázi Scopus

2-s2.0-85104681932