The first measurements of the Fourier coefficients (VnΔ) of the azimuthal distributions of charged hadrons emitted from photon-proton (γp) interactions are presented. The data are extracted from 68.8 nb−1 of ultra-peripheral proton-lead (pPb) collisions at sjavax.xml.bind.JAXBElement@6fc141b4=8.16TeV using the CMS detector. The high energy lead ions produce a flux of photons that can interact with the oncoming proton. This γp system provides a set of unique initial conditions with multiplicity lower than in photon-lead collisions but comparable to recent electron-positron and electron-proton data. The VnΔ coefficients are presented in ranges of event multiplicity and transverse momentum (pT) and are compared to corresponding hadronic minimum bias pPb results. For a given multiplicity range, the mean pT of charged particles is smaller in γp than in pPb collisions. For both the γp and pPb samples, V1Δ is negative, V2Δ is positive, and V3Δ consistent with 0. For each multiplicity and pT range, V2Δ is larger for γp events. The γp data are consistent with model predictions that have no collective effects.

Tumasyan, A., Adam, W., Bergauer, T., Dragicevic, M., Escalante Del Valle, A., Fruhwirth, R., et al. (2023). Two-particle azimuthal correlations in γp interactions using pPb collisions at sjavax.xml.bind.JAXBElement@1b87df45=8.16TeV. PHYSICS LETTERS. SECTION B, 844(10 September 2023) [10.1016/j.physletb.2023.137905].

Two-particle azimuthal correlations in γp interactions using pPb collisions at sjavax.xml.bind.JAXBElement@1b87df45=8.16TeV

Xiao J.;Benaglia A.;Beschi A.;Brivio F.;Cetorelli F.;Ciriolo V.;De Guio F.;Dinardo M. E.;Ghezzi A.;Govoni P.;Guzzi L.;Malberti M.;Massironi A.;Monti F.;Moroni L.;Paganoni M.;Ragazzi S.;Tabarelli de Fatis T.;Valsecchi D.;Zuolo D.;Ortona G.;Pigazzini S.;Gerosa R.;
2023

Abstract

The first measurements of the Fourier coefficients (VnΔ) of the azimuthal distributions of charged hadrons emitted from photon-proton (γp) interactions are presented. The data are extracted from 68.8 nb−1 of ultra-peripheral proton-lead (pPb) collisions at sjavax.xml.bind.JAXBElement@6fc141b4=8.16TeV using the CMS detector. The high energy lead ions produce a flux of photons that can interact with the oncoming proton. This γp system provides a set of unique initial conditions with multiplicity lower than in photon-lead collisions but comparable to recent electron-positron and electron-proton data. The VnΔ coefficients are presented in ranges of event multiplicity and transverse momentum (pT) and are compared to corresponding hadronic minimum bias pPb results. For a given multiplicity range, the mean pT of charged particles is smaller in γp than in pPb collisions. For both the γp and pPb samples, V1Δ is negative, V2Δ is positive, and V3Δ consistent with 0. For each multiplicity and pT range, V2Δ is larger for γp events. The γp data are consistent with model predictions that have no collective effects.
Articolo in rivista - Articolo scientifico
CMS; Collectivity; Photon-proton;
English
20-lug-2023
2023
844
10 September 2023
137905
none
Tumasyan, A., Adam, W., Bergauer, T., Dragicevic, M., Escalante Del Valle, A., Fruhwirth, R., et al. (2023). Two-particle azimuthal correlations in γp interactions using pPb collisions at sjavax.xml.bind.JAXBElement@1b87df45=8.16TeV. PHYSICS LETTERS. SECTION B, 844(10 September 2023) [10.1016/j.physletb.2023.137905].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/453121
Citazioni
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 0
Social impact