The pseudorapidity density of charged particles, dNch/dη , in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN−−−√ = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, |η|<1.8 . The dNch/dη value is 19.1±0.7 at |η|<0.5 . This quantity divided by ⟨Npart⟩ / 2 is 4.73±0.20 , where ⟨Npart⟩ is the average number of participating nucleons, is 9.5% higher than the corresponding value for p–Pb collisions at sNN−−−√ = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the dNch/dη distribution. Saturation-based models reproduce the distributions well for η>−1.3 . The dNch/dη is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.
Eser Adı (dc.title) | Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at √sNN = 8.16 TeV |
Yayın Türü (dc.type) | Makale |
Yazar/lar (dc.contributor.author) | KARASU UYSAL, Ayben |
Yazar/lar (dc.contributor.author) | ALICE Collaboration |
Atıf Dizini (dc.source.database) | Wos |
Atıf Dizini (dc.source.database) | Scopus |
Konu Başlıkları (dc.subject) | ALICE Experiment |
Konu Başlıkları (dc.subject) | LHC |
Konu Başlıkları (dc.subject) | Pseudorapidity Density |
Yayın Tarihi (dc.date.issued) | 2019 |
Kayıt Giriş Tarihi (dc.date.accessioned) | 2019-07-04T12:26:57Z |
Açık Erişim tarihi (dc.date.available) | 2019-07-04T12:26:57Z |
Orcid (dc.identifier.orcid) | 0000-0001-6297-2532 |
Özet (dc.description.abstract) | The pseudorapidity density of charged particles, dNch/dη , in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN−−−√ = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, |η|<1.8 . The dNch/dη value is 19.1±0.7 at |η|<0.5 . This quantity divided by ⟨Npart⟩ / 2 is 4.73±0.20 , where ⟨Npart⟩ is the average number of participating nucleons, is 9.5% higher than the corresponding value for p–Pb collisions at sNN−−−√ = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the dNch/dη distribution. Saturation-based models reproduce the distributions well for η>−1.3 . The dNch/dη is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity. |
Tek Biçim Adres (dc.identifier.uri) | https://hdl.handle.net/20.500.12498/423 |