Records |
Author |
LHCb Collaboration (Aaij, R. et al); Jaimes Elles, S.J.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Rebollo De Miguel, M.; Sanderswood, I.; Zhuo, J. |
Title |
Measurement of J/ψ-pair production in pp collisions at √s=13 TeV and study of gluon transverse-momentum dependent PDFs |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
03 |
Issue |
3 |
Pages |
088 - 40pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Hadron-Hadron Scattering; Multi-Parton Interactions; QCD; Quarkonium |
Abstract |
The production cross-section of J/psi pairs in proton-proton collisions at a centre-of-mass energy of root s = 13TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fb(-1) collected by the LHCb experiment. The measurement is performed with both J/psi mesons in the transverse momentum range 0 < p(T) < 14 GeV/c and rapidity range 2.0 < y < 4.5. The cross-section of this process is measured to be 16.36 +/- 0.28 (stat) +/- 0.88 (syst) nb. The contributions from single-parton scattering and double-parton scattering are separated based on the dependence of the cross-section on the absolute rapidity difference Delta y between the two J/psi mesons. The effective cross-section of double-parton scattering is measured to be sigma(eff) = 13.1 +/- 1.8 (stat) +/- 2.3 (syst) mb. The distribution of the azimuthal angle phi(CS) of one of the J/psi mesons in the Collins-Soper frame and the p(T)-spectrum of the J/psi pairs are also measured for the study of the gluon transverse-momentum dependent distributions inside protons. The extracted values of < cos4 phi(CS)> and < cos2 phi(CS)> are consistent with zero, but the presence of azimuthal asymmetry at a few percent level is allowed. |
Address |
[Egede, U.; Fujii, Y.; Hadavizadeh, T.; Henderson, R. D. L.; Lane, J. J.; Monk, M.; Song, R.; Walton, E. J.; Ward, J. A.] Monash Univ, Sch Phys & Astron, Melbourne, Australia, Email: li.xu@cern.ch |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001194594600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6050 |
Permanent link to this record |
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Author |
Balbinot, R.; Fabbri, A. |
Title |
The Unruh Vacuum and the “In-Vacuum” in Reissner-Nordström Spacetime |
Type |
Journal Article |
Year |
2024 |
Publication |
Universe |
Abbreviated Journal |
Universe |
Volume |
10 |
Issue |
1 |
Pages |
18 - 14pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Hawking radiation; Unruh vacuum; Reissner-Nordstrom black holes |
Abstract |
The Unruh vacuum is widely used as a quantum state to describe black hole evaporation since, near the horizon, it reproduces the physical state of a quantum field, the so-called “in-vacuum”, in the case where a black hole is formed by gravitational collapse. We examine the relation between these two quantum states in the background spacetime of a Reissner-Nordstrom black hole (both extremal and not), highlighting the similarities and striking differences. |
Address |
[Balbinot, Roberto] Univ Bologna, Dipartimento Fis, Via Irnerio 46, I-40126 Bologna, Italy, Email: roberto.balbinot@unibo.it; |
Corporate Author |
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Thesis |
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Publisher |
Mdpi |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001151025300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5914 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Jaimes Elles, S.J.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Rebollo De Miguel, M.; Ruiz Vidal, J.; Sanderswood, I.; Zhuo, J. |
Title |
Measurement of prompt D+ and Ds+ production in pPb collisions at √s_NN=5.02 TeV |
Type |
Journal Article |
Year |
2024 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
070 - 43pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Heavy Quark Production; Relativistic Heavy Ion Physics; QCD; Heavy Ion Experiments |
Abstract |
The production of prompt D+ and D-s(+) mesons is studied in proton-lead collisions at a centre-of-mass energy of root s(NN) = 5.02TeV. The data sample corresponding to an integrated luminosity of (1.58 +/- 0.02)nb(-1) is collected by the LHCb experiment at the LHC. The differential production cross-sections are measured using D+ and D-s(+) candidates with transverse momentum in the range of 0 < p(T) < 14 GeV/c and rapidities in the ranges of 1.5 < y* < 4.0 and -5.0 < y* < -2.5 in the nucleon-nucleon centre-of-mass system. For both particles, the nuclear modification factor and the forward-backward production ratio are determined. These results are compared with theoretical models that include initial-state nuclear effects. In addition, measurements of the cross-section ratios between D+, D-s(+) and D-0 mesons are presented, providing a baseline for studying the charm hadronization in lead-lead collisions at LHC energies. |
Address |
[de Souza Leite, J. Baptista; Bediaga, I. B.; Torres, M. Cruz; Carneiro Da Graca, U. De Freitas; De Miranda, J. M.; dos Reis, A. C.; Falcao, L. N.; Gomes, A.; Massaferri, A.; Santoro, L.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: yiheng.luo@cern.ch |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001190227500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6021 |
Permanent link to this record |
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Author |
Nieves, J.; Feijoo, A.; Albaladejo, M.; Du, M.L. |
Title |
Lowest-lying 1/2- and 3/2- ΛQ resonances: From the strange to the bottom sectors |
Type |
Journal Article |
Year |
2024 |
Publication |
Progress in Particle and Nuclear Physics |
Abbreviated Journal |
Prog. Part. Nucl. Phys. |
Volume |
137 |
Issue |
|
Pages |
104118 - 23pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Heavy quark symmetry; Constituent quark-model; Molecule; Charmed; Bottomed |
Abstract |
We present a detailed study of the lowest-lying 1/2(-) and 3/2(-) Lambda Q resonances both in the heavy 2 2 quark (bottom and charm) and the strange sectors. We have paid special attention to the interplay between the constituent quark-model and chiral baryon-meson degrees of freedom, which are coupled using a unitarized scheme consistent with leading-order heavy quark symmetries. We show that the Lambda(b)(5912) [J(P) = 1/2(-)], Lambda(b)(5920) [J(P) = 3/2(-)] and the Lambda(c)(2625) [J(P) = 3/2-], and the Lambda(1520) [J(P) = 3/2(-)] admitting larger breaking corrections, are heavyquark spin-flavor siblings. They can be seen as dressed quark-model states with Sigma Q(()*()) pi molecular components of the order of 30%. The J(P)=1(-) Lambda(2595) has, however, a higher molecular 2 probability of at least 50%, and even values greater than 70% can be easily accommodated. This is because it is located almost on top of the threshold of the Sigma(c)pi pair, which largely influences its properties. Although the light degrees of freedom in this resonance would be coupled to spin-parity 1(-) as in the Lambda(b)(5912), Lambda(b)(5920) and Lambda(c)(2625), the Lambda(c)(2595) should not be considered as a heavy-quark spin-flavor partner of the former ones. We also show that the Lambda(1405) chiral two-pole pattern does not have analogs in the 1 – charmed and bottomed sectors, because the 2 N D-(*()) and N (B) over bar (()*()) channels do not play for heavy quarks the decisive role that the N (K) over bar does in the strange sector, and the notable influence of the bare quark-model states for the charm and bottom resonances. Finally, we predict the existence of two Lambda(b)(6070) and two Lambda(c)(2765) heavy-quark spin and flavor sibling odd parity states. |
Address |
[Nieves, J.; Feijoo, A.; Albaladejo, M.] Inst Fis Corpuscular, Ctr Mixto, CSIC UV, Valencia, Spain, Email: jmnieves@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0146-6410 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001243410100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6153 |
Permanent link to this record |
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Author |
Miyagawa, P.S. et al; Bernabeu, P.; Lacasta, C.; Solaz, C.; Soldevila, U. |
Title |
Analysis of the results from Quality Control tests performed on ATLAS18 Strip Sensors during on-going production |
Type |
Journal Article |
Year |
2024 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
1064 |
Issue |
|
Pages |
169457 - 9pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
HL-LHC; ATLAS; ITk; Strip sensors |
Abstract |
The ATLAS experiment will replace its existing Inner Detector with the new all -silicon Inner Tracker (ITk) to cope with the operating conditions of the forthcoming high -luminosity phase of the LHC (HL-LHC). The outer regions of the ITk will be instrumented with similar to 18000 ATLAS18 strip sensors fabricated by Hamamatsu Photonics K.K. (HPK). With the launch of full-scale sensor production in 2021, the ITk strip sensor community has undertaken quality control (QC) testing of these sensors to ensure compliance with mechanical and electrical specifications agreed with HPK. The testing is conducted at seven QC sites on each of the monthly deliveries of similar to 500 sensors. This contribution will give an overview of the QC procedures and analysis; the tests most likely to determine pass/fail for a sensor are IV, long-term leakage current stability, full strip test and visual inspection. The contribution will then present trends in the results and properties following completion of similar to 60% of production testing. It will also mention challenges overcome through collaborative efforts with HPK during the early phases of production. With less than 5% of sensors rejected by QC testing, the overall production quality has been very good. |
Address |
[Miyagawa, P. S.; Beck, G. A.; Bevan, A. J.; Chen, Z.; Dawson, I.; Zenz, S. C.] Queen Mary Univ London, Particle Phys Res Ctr, GO Jones Bldg, Mile End Rd, London E14NS, England, Email: paul.miyagawa@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0168-9002 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001249611300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
6158 |
Permanent link to this record |