Constraints on the chi(c1 )versus chi(c2) Polarizations in Proton-Proton Collisions at root s=8 TeV
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10412586" target="_blank" >RIV/00216208:11320/20:10412586 - isvavai.cz</a>
Výsledek na webu
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=osXS9_QOvn" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=osXS9_QOvn</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1103/PhysRevLett.124.162002" target="_blank" >10.1103/PhysRevLett.124.162002</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Constraints on the chi(c1 )versus chi(c2) Polarizations in Proton-Proton Collisions at root s=8 TeV
Popis výsledku v původním jazyce
The polarizations of promptly produced chi(c1) and chi(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at root s = 8 TeV. The chi(c) states are reconstructed via their radiative decays chi(c) -> J/psi gamma, with the photons being measured through conversions to e(+)e(-), which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the chi(c2) to chi(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/psi -> mu(+)mu(-) decay, in three bins of J/psi transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the hclicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum.
Název v anglickém jazyce
Constraints on the chi(c1 )versus chi(c2) Polarizations in Proton-Proton Collisions at root s=8 TeV
Popis výsledku anglicky
The polarizations of promptly produced chi(c1) and chi(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at root s = 8 TeV. The chi(c) states are reconstructed via their radiative decays chi(c) -> J/psi gamma, with the photons being measured through conversions to e(+)e(-), which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the chi(c2) to chi(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/psi -> mu(+)mu(-) decay, in three bins of J/psi transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the hclicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10303 - Particles and field physics
Návaznosti výsledku
Projekt
Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.
Návaznosti
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Ostatní
Rok uplatnění
2020
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
Physical Review Letters
ISSN
0031-9007
e-ISSN
—
Svazek periodika
124
Číslo periodika v rámci svazku
16
Stát vydavatele periodika
US - Spojené státy americké
Počet stran výsledku
18
Strana od-do
162002
Kód UT WoS článku
000528518000007
EID výsledku v databázi Scopus
—