Protons consist of three valence quarks: two up-quarks and one down-quark, held together by gluons and a sea of quark-antiquark pairs. Collectively, quarks and gluons are referred to as partons. In a proton-proton collision, typically only one parton of each proton undergoes a hard scattering – referred to as single-parton scattering – leaving the remainder of each proton only slightly disturbed. Here, we report the study of double- and triple-parton scatterings through the simultaneous production of three \( J/\psi \) mesons, which consist of a charm quark-antiquark pair, in proton-proton collisions recorded with the CMS experiment at the Large Hadron Collider. We observed this process, reconstructed through the decays of \( J/\psi \) mesons into pairs of oppositely charged muons, with a statistical significance above five standard deviations. We measured the inclusive fiducial cross-section to be \( 272^{+141}_{-104} \, \text{(stat)} \pm 17 \, \text{(syst)} \, \text{fb} \), and compared it to theoretical expectations for triple-\( J/\psi \) meson production in single-, double-, and triple-parton scattering scenarios. Assuming factorization of multiple hard-scattering probabilities in terms of single-parton scattering cross-sections, double- and triple-parton scattering are the dominant contributions for the measured process.

Observation of triple J/ψ meson production in proton-proton collisions / Null, N., Tumasyan, A., Adam, W., Andrejkovic, J.W., Bergauer, T., Chatterjee, S., Damanakis, K., Dragicevic, M., Del Valle, A.E., Frühwirth, R., Jeitler, M., Krammer, N., Lechner, L., Liko, D., Mikulec, I., Paulitsch, P., Pitters, F.M., Schieck, J., Schöfbeck, R., Schwarz, D., et al.. - In: NATURE PHYSICS. - ISSN 1745-2473. - 19:3(2023), pp. 338-350. [10.1038/s41567-023-01992-x]

Observation of triple J/ψ meson production in proton-proton collisions

Re, D. Del;Organtini, G.;Paramatti, R.;Quaranta, C.;Rahatlou, S.;Santanastasio, F.;
2023

Abstract

Protons consist of three valence quarks: two up-quarks and one down-quark, held together by gluons and a sea of quark-antiquark pairs. Collectively, quarks and gluons are referred to as partons. In a proton-proton collision, typically only one parton of each proton undergoes a hard scattering – referred to as single-parton scattering – leaving the remainder of each proton only slightly disturbed. Here, we report the study of double- and triple-parton scatterings through the simultaneous production of three \( J/\psi \) mesons, which consist of a charm quark-antiquark pair, in proton-proton collisions recorded with the CMS experiment at the Large Hadron Collider. We observed this process, reconstructed through the decays of \( J/\psi \) mesons into pairs of oppositely charged muons, with a statistical significance above five standard deviations. We measured the inclusive fiducial cross-section to be \( 272^{+141}_{-104} \, \text{(stat)} \pm 17 \, \text{(syst)} \, \text{fb} \), and compared it to theoretical expectations for triple-\( J/\psi \) meson production in single-, double-, and triple-parton scattering scenarios. Assuming factorization of multiple hard-scattering probabilities in terms of single-parton scattering cross-sections, double- and triple-parton scattering are the dominant contributions for the measured process.
2023
LHC; cms; jpsi
01 Pubblicazione su rivista::01a Articolo in rivista
Observation of triple J/ψ meson production in proton-proton collisions / Null, N., Tumasyan, A., Adam, W., Andrejkovic, J.W., Bergauer, T., Chatterjee, S., Damanakis, K., Dragicevic, M., Del Valle, A.E., Frühwirth, R., Jeitler, M., Krammer, N., Lechner, L., Liko, D., Mikulec, I., Paulitsch, P., Pitters, F.M., Schieck, J., Schöfbeck, R., Schwarz, D., et al.. - In: NATURE PHYSICS. - ISSN 1745-2473. - 19:3(2023), pp. 338-350. [10.1038/s41567-023-01992-x]
File allegati a questo prodotto
File Dimensione Formato  
Tumasyan_Observation-of-triple_2023.pdf

accesso aperto

Note: Articolo su rivista
Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Creative commons
Dimensione 2.14 MB
Formato Adobe PDF
2.14 MB Adobe PDF

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/11573/1719781
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 11
social impact