Upul Sonnadara

University of Colombo

H-index: 62

Asia-Sri Lanka

About Upul Sonnadara

Upul Sonnadara, With an exceptional h-index of 62 and a recent h-index of 56 (since 2020), a distinguished researcher at University of Colombo, specializes in the field of Particle Physics, Computational Science, Atmospheric Sciences.

His recent articles reflect a diverse array of research interests and contributions to the field:

Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at s= 13 TeV

Search for long-lived particles decaying in the CMS muon detectors in proton-proton collisions at = 13 TeV

Measurements of azimuthal anisotropy of nonprompt D0 mesons in PbPb collisions at sNN= 5.02 TeV

Measurement of multijet azimuthal correlations and determination of the strong coupling in proton-proton collisions at = 13 TeV

A search for bottom-type vector-like quark pair production in dileptonic and fully hadronic final states in proton-proton collisions at = 13 TeV

Search for long-lived particles using displaced vertices and missing transverse momentum in proton-proton collisions at = 13 TeV

Review of top quark mass measurements in CMS

Performance of the CMS electromagnetic calorimeter in pp collisions at = 13 TeV

Upul Sonnadara Information

University	University of Colombo
Position	Professor of Physics Sri Lanka
Citations(all)	15781
Citations(since 2020)	12358
Cited By	4146
hIndex(all)	62
hIndex(since 2020)	56
i10Index(all)	260
i10Index(since 2020)	203
Email	Access Email
University Profile Page	University of Colombo

Upul Sonnadara Skills & Research Interests

Particle Physics

Computational Science

Atmospheric Sciences

Top articles of Upul Sonnadara

Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at s= 13 TeV

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Alberto Escalante Del Valle,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre Van Mechelen,Emil Sørensen Bols,Jorgen D’Hondt,Soumya Dansana,Alexandre De Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Inna Makarenko,Alexander Morton,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Michael Tytgat,Senne Van Putte,David Vannerom,Barbara Clerbaux,Gilles De Lentdecker,Laurent Favart,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,M Vanden Bemden,C Vander Velde,P Vanlaer,M De Coen,D Dobur,J Knolle,L Lambrecht,G Mestdach,C Rendón,A Samalan,K Skovpen,N Van Den Bossche,L Wezenbeek,A Benecke,G Bruno,C Caputo,C Delaere,IS Donertas,A Giammanco,K Jaffel,Sa Jain,V Lemaitre,J Lidrych,P Mastrapasqua,K Mondal,TT Tran,S Wertz,GA Alves,E Coelho,C Hensel,T Menezes De Oliveira,A Moraes,P Rebello Teles,M Soeiro,WL Aldá Júnior,M Alves Gallo Pereira,Barroso Ferreira Filho,H Brandao Malbouisson,W Carvalho,J Chinellato,EM Da Costa,GG Da Silveira,D De Jesus Damiao,S Fonseca De Souza,J Martins,C Mora Herrera,K Mota Amarilo,L Mundim,H Nogima,A Santoro,SM Silva Do Amaral,A Sznajder,M Thiel,A Vilela Pereira,CA Bernardes,L Calligaris,TR Tomei,EM Gregores,PG Mercadante,SF Novaes,B Orzari,Sandra S Padula,A Aleksandrov,G Antchev,R Hadjiiska,P Iaydjiev,M Misheva,M Shopova,G Sultanov,A Dimitrov,T Ivanov,L Litov,B Pavlov,P Petkov,A Petrov,E Shumka,S Keshri,S Thakur,T Cheng,Q Guo,T Javaid,M Mittal,L Yuan,G Bauer,Z Hu,K Yi,GM Chen,HS Chen,M Chen,F Iemmi,CH Jiang,A Kapoor,H Liao,ZA Liu,F Monti,R Sharma,JN Song,J Tao

Journal

Physical Review Letters

Published Date

2024/1/23

A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138 fb− 1 of proton-proton (p p) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016–2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ (p p→ A′→ χ 1 χ 2) and the decay branching fraction B (χ 2→ χ 1 μ+ μ−), where A′ is a dark photon and χ 1 and χ 2 are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter.

Search for long-lived particles decaying in the CMS muon detectors in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan

Published Date

2024/2/22

An inclusive search for long-lived exotic particles (LLPs) decaying to final states with a pair of muons is presented. The search uses data corresponding to an integrated luminosity of 36.6 fb collected by the CMS experiment from the proton-proton collisions at = 13.6 TeV in 2022, the first year of Run 3 of the CERN LHC. The experimental signature is a pair of oppositely charged muons originating from a common vertex spatially separated from the proton-proton interaction point by distances ranging from several hundred m to several meters. The sensitivity of the search benefits from new triggers for displaced dimuons developed for Run 3. The results are interpreted in the framework of the hidden Abelian Higgs model, in which the Higgs boson decays to a pair of long-lived dark photons, and of an -parity violating supersymmetry model, in which long-lived neutralinos decay to a pair of muons and a neutrino. The limits set on these models are the most stringent to date in wide regions of lifetimes for LLPs with masses larger than 10 GeV.

Measurements of azimuthal anisotropy of nonprompt D0 mesons in PbPb collisions at sNN= 5.02 TeV

Authors

Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,A Escalante Del Valle,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Lukas Lechner,Dietrich Liko,Ivan Mikulec,Peter Paulitsch,Florian Michael Pitters,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,C-E Wulz,Mohamed Rashad Darwish,Tahys Janssen,Tomas Kello,H Rejeb Sfar,Pierre Van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Alexandre De Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Seth Moortgat,Alexander Morton,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Walter Van Doninck,David Vannerom,Barbara Clerbaux,Gilles De Lentdecker,Laurent Favart,Dmytro Hohov,Johny Jaramillo,Kyeongpil Lee,Mostafa Mahdavikhorrami,Inna Makarenko,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,M Vanden Bemden,C Vander Velde,P Vanlaer,D Dobur,J Knolle,L Lambrecht,G Mestdach,C Rendón,A Samalan,K Skovpen,M Tytgat,N Van Den Bossche,B Vermassen,L Wezenbeek,A Benecke,G Bruno,F Bury,C Caputo,P David,C Delaere,IS Donertas,A Giammanco,K Jaffel,Sa Jain,V Lemaitre,K Mondal,A Taliercio,TT Tran,P Vischia,S Wertz,GA Alves,E Coelho,C Hensel,A Moraes,P Rebello Teles,WL Aldá Júnior,M Alves Gallo Pereira,M Barroso Ferreira Filho,H Brandao Malbouisson,W Carvalho,J Chinellato,EM Da Costa,GG Da Silveira,D De Jesus Damiao,V Dos Santos Sousa,S Fonseca De Souza,J Martins,C Mora Herrera,K Mota Amarilo,L Mundim,H Nogima,A Santoro,SM Silva Do Amaral,A Sznajder,M Thiel,F Torres Da Silva De Araujo,A Vilela Pereira,CA Bernardes,L Calligaris,TR Fernandez Perez Tomei,EM Gregores,PG Mercadante,SF Novaes,Sandra S Padula,A Aleksandrov,G Antchev,R Hadjiiska,P Iaydjiev,M Misheva,M Rodozov,M Shopova,G Sultanov,A Dimitrov,T Ivanov,L Litov,B Pavlov,P Petkov,A Petrov,E Shumka,S Thakur,T Cheng,T Javaid,M Mittal,L Yuan,M Ahmad,G Bauer,Z Hu,S Lezki,K Yi,GM Chen,HS Chen,M Chen,F Iemmi,CH Jiang,A Kapoor,H Liao

Journal

Physics Letters B

Published Date

2024/2/12

Measurements of the elliptic (v 2) and triangular (v 3) azimuthal anisotropy coefficients are presented for Image 1 mesons produced in Image 2 hadron decays (nonprompt Image 1 mesons) in lead-lead collisions at s NN= 5.02 TeV. The results are compared with previously published charm meson anisotropies measured using prompt Image 1 mesons. The data were collected with the CMS detector in 2018 with an integrated luminosity of 0.58 nb− 1. Azimuthal anisotropy is sensitive to the interactions of quarks with the hot and dense medium created in heavy ion collisions. Comparing results for prompt and nonprompt Image 1 mesons can assist in understanding the mass dependence of these interactions. The nonprompt results show lower magnitudes of v 2 and v 3 and weaker dependences on the meson transverse momentum and collision centrality than those found for prompt Image 1 mesons. The results are …

Measurement of multijet azimuthal correlations and determination of the strong coupling in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Ang Li,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Inna Makarenko,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Michael Tytgat,Gerrit Patrick van Onsem,Senne van Putte,David Vannerom,Barbara Clerbaux,Aloke Kumar Das,Gilles de Lentdecker,Laurent Favart,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Yanwen Hong,Joscha Knolle,Luka Lambrecht,Gianny Mestdach,Kevin Mota Amarilo,César Rendón,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Jan van der Linden,Liam Wezenbeek,Anna Benecke,Agni Bethani,Giacomo Bruno,Claudio Caputo,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Khawla Jaffel,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Kuntal Mondal,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Eduardo Coelho,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Walter Luiz Aldá Júnior,Miguel Alves Gallo Pereira,Mapse Barroso Ferreira Filho,Helena Brandao Malbouisson,Wagner Carvalho,Jose Chinellato,Eliza Melo da Costa,Gustavo Gil da Silveira,Dilson de Jesus Damiao,Sandro Fonseca de Souza,Raphael Gomes de Souza,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Antonio Vilela Pereira,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Pedro G Mercadante,Sergio F Novaes,Breno Orzari,Sandra Padula,Aleksandar Aleksandrov,Georgy Antchev,Roumyana Hadjiiska,Plamen Iaydjiev,Milena Misheva,Mariana Shopova,Georgi Sultanov,Anton Dimitrov,Leander Litov,Borislav Pavlov,Peicho Petkov,Anton Petrov,Elton Shumka,Sumit Keshri,Shalini Thakur,Tongguang Cheng,Qianying Guo,Tahir Javaid,Li Yuan,Zhen Hu,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor,Hongbo Liao,Zhenan Liu,Ramkrishna Sharma,Jia-Ning Song,Junquan Tao

Journal

arXiv preprint arXiv:2404.16082

Published Date

2024/4/26

A measurement is presented of a ratio observable that provides a measure of the azimuthal correlations among jets with large transverse momentum . This observable is measured in multijet events over the range of = 360-3170 GeV based on data collected by the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 134 fb. The results are compared with predictions from Monte Carlo parton-shower event generator simulations, as well as with fixed-order perturbative quantum chromodynamics (pQCD) predictions at next-to-leading-order (NLO) accuracy obtained with different parton distribution functions (PDFs) and corrected for nonperturbative and electroweak effects. Data and theory agree within uncertainties. From the comparison of the measured observable with the pQCD prediction obtained with the NNPDF3.1 NLO PDFs, the strong coupling at the Z boson mass scale is = 0.1177 0.0013 (exp) (theo) = 0.1177, where the total uncertainty is dominated by the scale dependence of the fixed-order predictions. A test of the running of in the TeV region shows no deviation from the expected NLO pQCD behaviour.

A search for bottom-type vector-like quark pair production in dileptonic and fully hadronic final states in proton-proton collisions at = 13 TeV

Authors

Published Date

2024/2/27

A search is described for the production of a pair of bottom-type vector-like quarks (B VLQs) with mass greater than 1000 GeV. Each B VLQ decays into a b quark and a Higgs boson, a b quark and a Z boson, or a t quark and a W boson. This analysis considers both fully hadronic final states and those containing a charged lepton pair from a Z boson decay. The products of the H bb boson decay and of the hadronic Z or W boson decays can be resolved as two distinct jets or merged into a single jet, so the final states are classified by the number of reconstructed jets. The analysis uses data corresponding to an integrated luminosity of 138 fb collected in proton-proton collisions at = 13 TeV with the CMS detector at the LHC from 2016 to 2018. No excess over the expected background is observed. Lower limits are set on the B VLQ mass at 95% confidence level. These depend on the B VLQ branching fractions and are 1570 and 1540 GeV for 100% B bH and 100% B bZ, respectively. In most cases, the mass limits obtained exceed previous limits by at least 100 GeV.

Search for long-lived particles using displaced vertices and missing transverse momentum in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan

Published Date

2024/2/24

A search for the production of long-lived particles in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC is presented. The search is based on data collected by the CMS experiment in 2016-2018, corresponding to a total integrated luminosity of 137 fb. This search is designed to be sensitive to long-lived particles with mean proper decay lengths between 0.1 and 1000 m, whose decay products produce a final state with at least one displaced vertex and missing transverse momentum. A machine learning algorithm, which improves the background rejection power by more than an order of magnitude, is applied to improve the sensitivity. The observation is consistent with the standard model background prediction, and the results are used to constrain split supersymmetry (SUSY) and gauge-mediated SUSY breaking models with different gluino mean proper decay lengths and masses. This search is the first CMS search that shows sensitivity to hadronically decaying long-lived particles from signals with mass differences between the gluino and neutralino below 100 GeV. It sets the most stringent limits to date for split-SUSY models and gauge-mediated SUSY breaking models with gluino proper decay length less than 6 m.

Review of top quark mass measurements in CMS

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Andre Hoang,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Ang Li,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Steven Lowette,Inna Makarenko,Denise Müller,Stefaan Tavernier,Michael Tytgat,Gerrit Patrick van Onsem,Senne van Putte,David Vannerom,Barbara Clerbaux,Aloke Kumar Das,Gilles de Lentdecker,Hugues Evard,Laurent Favart,Paraskevas Gianneios,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Fakhri Alam Khan,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Yanwen Hong,Joscha Knolle,Luka Lambrecht,Gianny Mestdach,Kevin Mota Amarilo,César Rendón,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Jan van der Linden,Liam Wezenbeek,Anna Benecke,Agni Bethani,Giacomo Bruno,Claudio Caputo,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Eduardo Coelho,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Walter Luiz Aldá Júnior,Miguel Alves Gallo Pereira,Mapse Barroso Ferreira Filho,Helena Brandao Malbouisson,Wagner Carvalho,Jose Chinellato,Eliza Melo da Costa,Gustavo Gil da Silveira,Dilson de Jesus Damiao,Sandro Fonseca de Souza,Raphael Gomes de Souza,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Joao Pedro Pinheiro,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Antonio Vilela Pereira,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Pedro G Mercadante,Sergio F Novaes,Breno Orzari,Sandra Padula,Aleksandar Aleksandrov,Georgy Antchev,Roumyana Hadjiiska,Plamen Iaydjiev,Milena Misheva,Mariana Shopova,Georgi Sultanov,Anton Dimitrov,Leander Litov,Borislav Pavlov,Peicho Petkov,Anton Petrov,Elton Shumka,Sumit Keshri,Shalini Thakur,Tongguang Cheng,Tahir Javaid,Li Yuan,Zhen Hu,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor,Hongbo Liao,Zhenan Liu,Ramkrishna Sharma,Jia-Ning Song,Junquan Tao,Chu Wang,Jin Wang

Journal

arXiv preprint arXiv:2403.01313

Published Date

2024/3/19

The top quark mass is one of the most intriguing parameters of the standard model (SM). Its value indicates a Yukawa coupling close to unity, and the resulting strong ties to the Higgs physics make the top quark mass a crucial ingredient for understanding essential aspects of the electroweak sector of the SM. While it is such an important parameter of the SM, its measurement and interpretation in terms of the Lagrangian parameter are challenging. The CMS Collaboration has performed multiple measurements of the top quark mass, addressing these challenges from different angles: highly precise `direct' measurements, using the top quark decay products, as well as `indirect' measurements aiming at accurate interpretations in terms of the Lagrangian parameter. Recent mass measurements using Lorentz-boosted top quarks are particularly promising, opening a new avenue of measurements based on top quark decay products contained in a single particle jet, with superior prospects for accurate theoretical interpretations. Moreover, dedicated studies of the dominant uncertainties in the modelling of the signal processes have been performed. This review offers the first comprehensive overview of these measurements performed by the CMS Collaboration using the data collected at centre-of-mass energies of 7, 8, and 13 TeV.

Performance of the CMS electromagnetic calorimeter in pp collisions at = 13 TeV

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Alberto Escalante del Valle,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Inna Makarenko,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Michael Tytgat,Senne van Putte,David Vannerom,Barbara Clerbaux,Gilles de Lentdecker,Laurent Favart,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Yanwen Hong,Joscha Knolle,Luka Lambrecht,Gianny Mestdach,César Rendón,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Liam Wezenbeek,Anna Benecke,Giacomo Bruno,Claudio Caputo,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Khawla Jaffel,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Kuntal Mondal,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Eduardo Coelho,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Walter Luiz Aldá Júnior,Miguel Alves Gallo Pereira,Mapse Barroso Ferreira Filho,Helena Brandao Malbouisson,Wagner Carvalho,Jose Chinellato,Eliza Melo da Costa,Gustavo Gil da Silveira,Dilson de Jesus Damiao,Sandro Fonseca de Souza,Jordan Martins,Clemencia Mora Herrera,Kevin Mota Amarilo,Luiz Mundim,Helio Nogima,Alberto Santoro,Sheila Mara Silva Do Amaral,Andre Sznajder,Mauricio Thiel,Antonio Vilela Pereira,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Pedro G Mercadante,Sergio F Novaes,Breno Orzari,Sandra Padula,Aleksandar Aleksandrov,Georgy Antchev,Roumyana Hadjiiska,Plamen Iaydjiev,Milena Misheva,Mariana Shopova,Georgi Sultanov,Anton Dimitrov,Todor Ivanov,Leander Litov,Borislav Pavlov,Peicho Petkov,Anton Petrov,Elton Shumka,Sumit Keshri,Shalini Thakur,Tongguang Cheng,Qianying Guo,Tahir Javaid,Monika Mittal,Li Yuan,Gerry Bauer,Zhen Hu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor,Hongbo Liao,Zhenan Liu,Fabio Monti,Ramkrishna Sharma,Jia-Ning Song,Junquan Tao,Chu Wang

Journal

arXiv preprint arXiv:2403.15518

Published Date

2024/4/2

The operation and performance of the Compact Muon Solenoid (CMS) electromagnetic calorimeter (ECAL) are presented, based on data collected in pp collisions at = 13 TeV at the CERN LHC, in the years from 2015 to 2018 (LHC Run 2), corresponding to an integrated luminosity of 151 fb. The CMS ECAL is a scintillating lead-tungstate crystal calorimeter, with a silicon strip preshower detector in the forward region that provides precise measurements of the energy and the time-of-arrival of electrons and photons. The successful operation of the ECAL is crucial for a broad range of physics goals, ranging from observing the Higgs boson and measuring its properties, to other standard model measurements and searches for new phenomena. Precise calibration, alignment, and monitoring of the ECAL response are important ingredients to achieve these goals. To face the challenges posed by the higher luminosity, which characterized the operation of the LHC in Run 2, the procedures established during the 2011-2012 run of the LHC have been revisited and new methods have been developed for the energy measurement and for the ECAL calibration. The energy resolution of the calorimeter, for electrons from Z boson decays reaching the ECAL without significant loss of energy by bremsstrahlung, was better than 1.8%, 3.0%, and 4.5% in the $\lvert\eta\rvert$ intervals [0.0,0.8], [0.8,1.5], [1.5, 2.5], respectively. This resulting performance is similar to that achieved during Run 1 in 2011-2012, in spite of the more severe running conditions.

Search for Higgs boson pair production with one associated vector boson in proton-proton collisions at = 13 TeV

Authors

CMS Collaboration

Journal

arXiv preprint arXiv:2404.08462

Published Date

2024/4/12

A search for Higgs boson pair (HH) production in association with a vector boson V (W or Z boson) is presented. The search is based on proton-proton collision data at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb. All hadronic and leptonic decays of V bosons are used. The leptons considered are electrons, muons, and neutrinos. The HH production is searched for in the decay channel. An observed (expected) upper limit at 95% confidence level of VHH production cross section is set at 294 (124) times the standard model prediction. Constraints are also set on the modifiers of the Higgs boson trilinear self-coupling, , assuming = 1 and vice versa on the coupling of two Higgs bosons with two vector bosons, . The observed (expected) 95% confidence intervals of these coupling modifiers are -37.7 37.2 (-30.1 8.9) and -12.2 13.5 (-7.2 8.9), respectively.

Muon identification using multivariate techniques in the CMS experiment in proton-proton collisions at√ S= 13 TeV

Authors

CMS Collaboration

Journal

arXiv preprint arXiv:2310.03844

Published Date

2023/10/5

The identification of prompt and isolated muons, as well as muons from heavy-flavour hadron decays, is an important task. We developed two multivariate techniques to provide highly efficient identification for muons with transverse momentum greater than 10\GeV. One provides a continuous variable as an alternative to a cut-based identification selection and offers a better discrimination power against misidentified muons. The other one selects prompt and isolated muons by using isolation requirements to reduce the contamination from nonprompt muons arising in heavy-flavour hadron decays. Both algorithms are developed using 59.7 fb of proton-proton collisions data at a centre-of-mass energy of = 13 TeV collected in 2018 with the CMS experiment at the CERN LHC.

Test of lepton flavor universality in B K and B Kee decays in proton-proton collisions at = 13 TeV

Authors

CMS Collaboration

Journal

arXiv preprint arXiv:2401.07090

Published Date

2024/1/13

A test of lepton flavor universality in B K and B Kee decays, as well as a measurement of differential and integrated branching fractions of a nonresonant B K decay are presented. The analysis is made possible by a dedicated data set of proton-proton collisions at = 13 TeV recorded in 2018, by the CMS experiment at the LHC, using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron decays. The ratio of the branching fractions (B K) to (B Kee) is determined from the measured double ratio (K) of these decays to the respective branching fractions of the B J/K with J/ and ee decays, which allow for significant cancellation of systematic uncertainties. The ratio (K) is measured in the range 1.1 6.0 GeV, where is the invariant mass of the lepton pair, and is found to be (K) = 0.78, in agreement with the standard model expectation (K) 1. This measurement is limited by the statistical precision of the electron channel. The integrated branching fraction in the same range, (B K) = (12.42 0.68) 10, is consistent with the present world-average value and has a comparable precision.

Combined search for electroweak production of winos, binos, higgsinos, and sleptons in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan

Published Date

2024/2/2

A combination of the results of several searches for the electroweak production of the supersymmetric partners of standard model bosons, and of charged leptons, is presented. All searches use proton-proton collision data at = 13 TeV recorded with the CMS detector at the LHC in 2016-2018. The analyzed data correspond to an integrated luminosity of up to 137 fb. The results are interpreted in terms of simplified models of supersymmetry. Two new interpretations are added with this combination: a model spectrum with the bino as the lightest supersymmetric particle together with mass-degenerate higgsinos decaying to the bino and a standard model boson, and the compressed-spectrum region of a previously studied model of slepton pair production. Improved analysis techniques are employed to optimize sensitivity for the compressed spectra in the wino and slepton pair production models. The results are consistent with expectations from the standard model. The combination provides a more comprehensive coverage of the model parameter space than the individual searches, extending the exclusion by up to 125 GeV, and also targets some of the intermediate gaps in the mass coverage.

Search for pair production of scalar and vector leptoquarks decaying to muons and bottom quarks in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan,Robin Erbacher,Camilo Andres Carrillo Montoya,Dave M Newbold,Wagner Carvalho,Nimmitha Karunarathna,Maciej Górski,Manuel Sommerhalder,Cole Lindsey,Nukulsinh Parmar,Balazs Ujvari,Ayse Polatoz,Anna Tsatsos,Elton Shumka,Alfredo Gurrola,Anne-Marie Magnan,Roumyana Hadjiiska,Ian Laflotte,Ian Mcalister,Willard Johns,Ludivine Ceard,Pierre Van Hove,Mohammad Alhusseini,Alberto Orso Maria Iorio,Ulrich Heintz,Giuseppe Latino,Andrew Hart,Robin Hofsaess,Federico Vazzoler,Sinan Sagir,Changgi Huh,Georgios Tsipolitis,Joseph Lynn Dulemba,Sanghyun Ko,Dylan Apparu,Soureek Mitra,Sergei Slabospitskii,Shamik Ghosh,Michael Tytgat,Robert Schöfbeck,Julia Vazquez Escobar,James Hirschauer,Andreas Nürnberg,Ho Fung Tsoi,Reza Goldouzian,Victor Golovtcov,Ram Krishna Dewanjee,Chiara Rovelli,Eliza Melo Da Costa,Daniele Fasanella,Polina Simkina,Vipin Bhatnagar,Zhen Hu,Hans Reithler,Austin Baty,Soumya Mukherjee,Tomas Lindén,Jonathon Langford,Graham Wilson,Younghoon Lee,William Tabb,Elena Popova,Furkan Dolek,Attilio Santocchia,Sergio Sánchez Navas,Manuel Calderon De La Barca Sanchez,Wolfram Dietrich Zeuner,Hesham El Faham,Jithin Madhusudanan Sreekala,Raphael Granier de Cassagnac,Georgios Daskalakis,Kin Ho Lo,Axel Buchot Perraguin,Andrés Abreu,Ernesto Migliore,Alexander Zotz,Tilman Rohe,Paul Schütze,Ece Asilar,Salvatore Nuzzo,Grace Cummings,Florian Joel J Bury,Gurkan Karaman,Henri Petrow,Jonathan Guiang,Kai-Feng Chen,Matthew Nguyen,Liam Brennan,Irene Dutta,Giorgio Apollinari,Michael Oshiro,Damir Lelas,Gillian Kopp,Michel Della Negra,Amitabh Lath,Daria Selivanova,Dennis Roy,Alexander Pauls,Martijn Mulders,Fabrizio Palla,Nikolas Pervan,Lorenzo Uplegger,Marina Kolosova,Sunil Bansal,Roberval Walsh,Hugo Becerril Gonzalez,Vladimir Makarenko,Christopher Palmer,Kristan Allan Hahn,Tao Huang,Olmo Cerri,George Stephans,Siqi Yuan,Luiz Mundim,Olena Karacheban,Alicia Calderon,Tyler Lam,Kevin Black,Thomas Kress,Georgia Karapostoli,Samuel Lascio,Fotios Ptochos,Berkan Kaynak,Wei Wei,Achille Petrilli,Diogo Bastos,Bhargav Madhusudan Joshi,Abhishikth Mallampalli,Chenfeng Lu,Maria Cepeda,Mauricio Thiel,Bingran Wang,J William Gary,Dylan Blend,Cécile Caillol,Yannik Rath,John Paul Chou,Nihar Ranjan Saha,Orgho Neogi,Mohammed Mahmoud,Peicho Petkov,John Rotter,Davide Piccolo,Florian Rehm,Pawel de Barbaro,Vaia Papadimitriou,Robert White,Nural Akchurin,Qianying Guo,Patrice Verdier

Published Date

2024/2/9

A search for pair production of scalar and vector leptoquarks (LQs) each decaying to a muon and a bottom quark is performed using proton-proton collision data collected at 13 TeV with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 138 fb . No excess above standard model expectation is observed. Scalar (vector) LQs with masses less than 1810 (2120) GeV are excluded at 95% confidence level, assuming a 100% branching fraction of the LQ decaying to a muon and a bottom quark. These limits represent the most stringent to date.

Search for exotic decays of the Higgs boson to a pair of pseudoscalars in the bb and bb final states

Authors

Aram Hayrapetyan

Published Date

2024/2/20

A search for exotic decays of the Higgs boson (H) with a mass of 125 GeV to a pair of light pseudoscalars is performed in final states where one pseudoscalar decays to two b quarks and the other to a pair of muons or leptons. A data sample of proton-proton collisions at = 13 TeV corresponding to an integrated luminosity of 138 fb recorded with the CMS detector is analyzed. No statistically significant excess is observed over the standard model backgrounds. Upper limits are set at 95% confidence level (CL) on the Higgs boson branching fraction to bb and to bb, via a pair of s. The limits depend on the pseudoscalar mass and are observed to be in the range (0.17-3.3) 10 and (1.7-7.7) 10 in the bb and bb final states, respectively. In the framework of models with two Higgs doublets and a complex scalar singlet (2HDM+S), the results of the two final states are combined to determine model-independent upper limits on the branching fraction (H bb) at 95% CL, with being a muon or a lepton. For different types of 2HDM+S, upper bounds on the branching fraction (H ) are extracted from the combination of the two channels. In most of the Type II 2HDM+S parameter space, H ) values above 0.23 are excluded at 95% CL for values between 15 and 60 GeV.

Two-particle Bose-Einstein correlations and their Lévy parameters in PbPb collisions at TeV

Authors

Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,A Escalante Del Valle,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Lukas Lechner,Dietrich Liko,Ivan Mikulec,Peter Paulitsch,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,C-E Wulz,Mohamed Rashad Darwish,Tahys Janssen,Tomas Kello,H Rejeb Sfar,Pierre Van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Alexandre De Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Alexander Morton,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Walter Van Doninck,Senne Van Putte,David Vannerom,Barbara Clerbaux,Soumya Dansana,Gilles De Lentdecker,Laurent Favart,Dmytro Hohov,Johny Jaramillo,Kyeongpil Lee,Mostafa Mahdavikhorrami,Inna Makarenko,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,M Vanden Bemden,C Vander Velde,P Vanlaer,D Dobur,J Knolle,L Lambrecht,G Mestdach,C Rendón,A Samalan,K Skovpen,M Tytgat,N Van Den Bossche,B Vermassen,L Wezenbeek,A Benecke,G Bruno,F Bury,C Caputo,P David,C Delaere,IS Donertas,A Giammanco,K Jaffel,Sa Jain,V Lemaitre,K Mondal,A Taliercio,TT Tran,P Vischia,S Wertz,GA Alves,E Coelho,C Hensel,A Moraes,P Rebello Teles,WL Aldá Júnior,M Alves Gallo Pereira,M Barroso Ferreira Filho,H Brandao Malbouisson,W Carvalho,J Chinellato,EM Da Costa,GG Da Silveira,D De Jesus Damiao,V Dos Santos Sousa,S Fonseca De Souza,J Martins,C Mora Herrera,K Mota Amarilo,L Mundim,H Nogima,A Santoro,SM Silva Do Amaral,A Sznajder,M Thiel,A Vilela Pereira,CA Bernardes,L Calligaris,TR Fernandez Perez Tomei,EM Gregores,PG Mercadante,SF Novaes,Sandra S Padula,A Aleksandrov,G Antchev,R Hadjiiska,P Iaydjiev,M Misheva,M Rodozov,M Shopova,G Sultanov,A Dimitrov,T Ivanov,L Litov,B Pavlov,P Petkov,A Petrov,E Shumka,S Thakur,T Cheng,T Javaid,M Mittal,L Yuan,M Ahmad,G Bauer,Z Hu,S Lezki,K Yi,GM Chen,HS Chen,M Chen,F Iemmi,CH Jiang,A Kapoor,H Liao,Z-A Liu

Journal

Physical Review C

Published Date

2024/2/23

Two-particle Bose–Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of s NN= 5.02 TeV. The data sample, containing 4.27× 10 9 minimum bias events corresponding to an integrated luminosity of 0.607 nb− 1, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a Lévy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the Lévy index or shape parameter α, the Lévy scale parameter R, and the correlation strength parameter λ. The source shape, characterized by α, is found to be neither Cauchy nor Gaussian, implying the need for a full Lévy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a …

Constraints on anomalous Higgs boson couplings from its production and decay using the WW channel in proton-proton collisions at = 13 TeV

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Ang Li,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Inna Makarenko,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Michael Tytgat,Gerrit Patrick van Onsem,Senne van Putte,David Vannerom,Barbara Clerbaux,Aloke Kumar Das,Gilles de Lentdecker,Laurent Favart,Paraskevas Gianneios,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Laurent Pétré,Nicolas Postiau,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Yanwen Hong,Joscha Knolle,Luka Lambrecht,Gianny Mestdach,Kevin Mota Amarilo,César Rendón,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Jan van der Linden,Liam Wezenbeek,Anna Benecke,Agni Bethani,Giacomo Bruno,Claudio Caputo,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Khawla Jaffel,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Kuntal Mondal,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Eduardo Coelho,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Walter Luiz Aldá Júnior,Miguel Alves Gallo Pereira,Mapse Barroso Ferreira Filho,Helena Brandao Malbouisson,Wagner Carvalho,Jose Chinellato,Eliza Melo da Costa,Gustavo Gil da Silveira,Dilson de Jesus Damiao,Sandro Fonseca de Souza,Raphael Gomes de Souza,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Joao Pedro Pinheiro,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Antonio Vilela Pereira,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Pedro G Mercadante,Sergio F Novaes,Breno Orzari,Sandra Padula,Aleksandar Aleksandrov,Georgy Antchev,Roumyana Hadjiiska,Plamen Iaydjiev,Milena Misheva,Mariana Shopova,Georgi Sultanov,Anton Dimitrov,Leander Litov,Borislav Pavlov,Peicho Petkov,Anton Petrov,Elton Shumka,Sumit Keshri,Shalini Thakur,Tongguang Cheng,Tahir Javaid,Li Yuan,Zhen Hu,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor,Hongbo Liao,Zhenan Liu,Ramkrishna Sharma,Jia-Ning Song

Journal

arXiv preprint arXiv:2403.00657

Published Date

2024/3/19

A study of the anomalous couplings of the Higgs boson to vector bosons, including -violation effects, has been conducted using its production and decay in the WW channel. This analysis is performed on proton-proton collision data collected with the CMS detector at the CERN LHC during 2016-2018 at a center-of-mass energy of 13 TeV, and corresponds to an integrated luminosity of 138 fb. The different-flavor dilepton (e) final state is analyzed, with dedicated categories targeting gluon fusion, electroweak vector boson fusion, and associated production with a W or Z boson. Kinematic information from associated jets is combined using matrix element techniques to increase the sensitivity to anomalous effects at the production vertex. A simultaneous measurement of four Higgs boson couplings to electroweak vector bosons is performed in the framework of a standard model effective field theory. All measurements are consistent with the expectations for the standard model Higgs boson and constraints are set on the fractional contribution of the anomalous couplings to the Higgs boson production cross section.

New Structures in the J/ψJ/ψ Mass Spectrum in Proton-Proton Collisions at s= 13 TeV

Authors

A Hayrapetyan,A Tumasyan,W Adam,JW Andrejkovic,T Bergauer,S Chatterjee,K Damanakis,M Dragicevic,A Escalante Del Valle,PS Hussain,M Jeitler,N Krammer,D Liko,I Mikulec,J Schieck,R Schöfbeck,D Schwarz,M Sonawane,S Templ,W Waltenberger,CE Wulz,MR Darwish,T Janssen,P Van Mechelen,ES Bols,J D’Hondt,S Dansana,A De Moor,M Delcourt,H El Faham,S Lowette,I Makarenko,D Müller,AR Sahasransu,S Tavernier,M Tytgat,S Van Putte,D Vannerom,B Clerbaux,G De Lentdecker,L Favart,D Hohov,J Jaramillo,A Khalilzadeh,K Lee,M Mahdavikhorrami,A Malara,S Paredes,L Pétré,N Postiau,L Thomas,M Vanden Bemden,C Vander Velde,P Vanlaer,M De Coen,D Dobur,Y Hong,J Knolle,L Lambrecht,G Mestdach,C Rendón,A Samalan,K Skovpen,N Van Den Bossche,L Wezenbeek,A Benecke,G Bruno,C Caputo,C Delaere,IS Donertas,A Giammanco,K Jaffel,Sa Jain,V Lemaitre,J Lidrych,P Mastrapasqua,K Mondal,TT Tran,S Wertz,GA Alves,E Coelho,C Hensel,T Menezes De Oliveira,A Moraes,P Rebello Teles,M Soeiro,WL Aldá Júnior,M Alves Gallo Pereira,Barroso Ferreira Filho,H Brandao Malbouisson,W Carvalho,J Chinellato,EM Da Costa,GG Da Silveira,D De Jesus Damiao,S Fonseca De Souza,J Martins,C Mora Herrera,K Mota Amarilo,L Mundim,H Nogima,A Santoro,SM Silva Do Amaral,A Sznajder,M Thiel,A Vilela Pereira,CA Bernardes,L Calligaris,TR Tomei,EM Gregores,PG Mercadante,SF Novaes,B Orzari,Sandra S Padula,A Aleksandrov,G Antchev,R Hadjiiska,P Iaydjiev,M Misheva,M Shopova,G Sultanov,A Dimitrov,T Ivanov,L Litov,B Pavlov,P Petkov,A Petrov,E Shumka,S Keshri,S Thakur,T Cheng,Q Guo,T Javaid,M Mittal,L Yuan,G Bauer,J Chen,J Gu,Z Hu,J Liu,X Wang,H Wen,K Yi,J Zhang,GM Chen,HS Chen,M Chen,F Iemmi,CH Jiang,A Kapoor

Journal

Physical Review Letters

Published Date

2024/3/15

A search is reported for near-threshold structures in the J/ψ J/ψ invariant mass spectrum produced in proton-proton collisions at s= 13 TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135 fb− 1. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638− 38+ 43 (stat)− 31+ 16 (syst) MeV. Another structure with even higher significance is found at a mass of 6847− 28+ 44 (stat)− 20+ 48 (syst) MeV, which is consistent with the X (6900) resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134− 25+ 48 (stat)− 15+ 41 (syst) MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference.

Search for the lepton flavor violating τ→ 3μ decay in proton-proton collisions at

Authors

A Hayrapetyan,A Tumasyan,W Adam,JW Andrejkovic,T Bergauer,S Chatterjee,K Damanakis,M Dragicevic,PS Hussain,M Jeitler,N Krammer,A Li,D Liko,I Mikulec,J Schieck,R Schöfbeck,D Schwarz,M Sonawane,S Templ,W Waltenberger,CE Wulz,MR Darwish,T Janssen,P Van Mechelen,ES Bols,J D'Hondt,S Dansana,A De Moor,M Delcourt,H El Faham,S Lowette,I Makarenko,D Müller,AR Sahasransu,S Tavernier,M Tytgat,S Van Putte,D Vannerom,B Clerbaux,G De Lentdecker,L Favart,D Hohov,J Jaramillo,A Khalilzadeh,K Lee,M Mahdavikhorrami,A Malara,S Paredes,L Pétré,N Postiau,L Thomas,M Vanden Bemden,C Vander Velde,P Vanlaer,M De Coen,D Dobur,Y Hong,J Knolle,L Lambrecht,G Mestdach,C Rendón,A Samalan,K Skovpen,N Van Den Bossche,L Wezenbeek,A Benecke,G Bruno,C Caputo,C Delaere,IS Donertas,A Giammanco,K Jaffel,Sa Jain,V Lemaitre,J Lidrych,P Mastrapasqua,K Mondal,TT Tran,S Wertz,GA Alves,E Coelho,C Hensel,T Menezes De Oliveira,A Moraes,P Rebello Teles,M Soeiro,WL Aldá Júnior,M Alves Gallo Pereira,Barroso Ferreira Filho,H Brandao Malbouisson,W Carvalho,J Chinellato,EM Da Costa,GG Da Silveira,D De Jesus Damiao,S Fonseca De Souza,J Martins,C Mora Herrera,K Mota Amarilo,L Mundim,H Nogima,A Santoro,A Sznajder,M Thiel,A Vilela Pereira,CA Bernardes,L Calligaris,TR Fernandez Perez Tomei,EM Gregores,PG Mercadante,SF Novaes,B Orzari,Sandra S Padula,A Aleksandrov,G Antchev,R Hadjiiska,P Iaydjiev,M Misheva,M Shopova,G Sultanov,A Dimitrov,L Litov,B Pavlov,P Petkov,A Petrov,E Shumka,S Keshri,S Thakur,T Cheng,Q Guo,T Javaid,L Yuan,Z Hu,J Liu,K Yi,GM Chen,HS Chen,M Chen,F Iemmi,CH Jiang,A Kapoor,H Liao,ZA Liu,R Sharma,JN Song,J Tao,C Wang,J Wang,Z Wang,H Zhang

Journal

Physics Letters B

Published Date

2024/4/10

A search for the lepton flavor violating τ→ 3μ decay is performed using proton-proton collision events at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC in 2017–2018, corresponding to an integrated luminosity of 97.7 fb− 1. Tau leptons produced in both heavy-flavor hadron and W boson decays are exploited in the analysis. No evidence for the decay is observed. The results of this search are combined with an earlier null result based on data collected in 2016 to obtain a total integrated luminosity of 131 fb− 1. The observed (expected) upper limits on the branching fraction(τ→ 3μ) at confidence levels of 90 and 95% are 2. 9× 10− 8 (2. 4× 10− 8) and 3. 6× 10− 8 (3. 0× 10− 8), respectively.

Luminosity determination using Z boson production at the CMS experiment

Authors

CMS collaboration

Journal

The European Physical Journal. C, Particles and Fields

Published Date

2024

The measurement of Z boson production is presented as a method to determine the integrated luminosity of CMS data sets. The analysis uses proton–proton collision data, recorded by the CMS experiment at the CERN LHC in 2017 at a center-of-mass energy of 13$\,\text {Te\hspace {-. 08em} V}$. Events with Z bosons decaying into a pair of muons are selected. The total number of Z bosons produced in a fiducial volume is determined, together with the identification efficiencies and correlations from the same data set, in small intervals of 20 of integrated luminosity, thus facilitating the efficiency and rate measurement as a function of time and instantaneous luminosity. Using the ratio of the efficiency-corrected numbers of Z bosons, the precisely measured integrated luminosity of one data set is used to determine the luminosity of another. For the first time, a full quantitative uncertainty analysis of the use of Z …

Extracting the speed of sound in the strongly interacting matter created in ultrarelativistic lead-lead collisions at the LHC

Authors

Aram Hayrapetyan,Armen Tumasyan,Wolfgang Adam,Janik Walter Andrejkovic,Thomas Bergauer,Suman Chatterjee,Konstantinos Damanakis,Marko Dragicevic,Priya Sajid Hussain,Manfred Jeitler,Natascha Krammer,Ang Li,Dietrich Liko,Ivan Mikulec,Jochen Schieck,Robert Schöfbeck,Dennis Schwarz,Mangesh Sonawane,Sebastian Templ,Wolfgang Waltenberger,Claudia-Elisabeth Wulz,Mohamed Rashad Darwish,Tahys Janssen,Pierre van Mechelen,Emil Sørensen Bols,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Hesham El Faham,Steven Lowette,Inna Makarenko,Denise Müller,Abanti Ranadhir Sahasransu,Stefaan Tavernier,Michael Tytgat,Gerrit Patrick van Onsem,Senne van Putte,David Vannerom,Barbara Clerbaux,Aloke Kumar Das,Gilles de Lentdecker,Laurent Favart,Paraskevas Gianneios,Dmytro Hohov,Johny Jaramillo,Ali Khalilzadeh,Kyeongpil Lee,Mostafa Mahdavikhorrami,Andrea Malara,Santiago Paredes,Nicolas Postiau,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Yanwen Hong,Joscha Knolle,Luka Lambrecht,Gianny Mestdach,Kevin Mota Amarilo,César Rendón,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Jan van der Linden,Liam Wezenbeek,Anna Benecke,Agni Bethani,Giacomo Bruno,Claudio Caputo,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Khawla Jaffel,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Kuntal Mondal,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Eduardo Coelho,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Walter Luiz Aldá Júnior,Miguel Alves Gallo Pereira,Mapse Barroso Ferreira Filho,Helena Brandao Malbouisson,Wagner Carvalho,Jose Chinellato,Eliza Melo da Costa,Gustavo Gil da Silveira,Dilson de Jesus Damiao,Sandro Fonseca de Souza,Raphael Gomes de Souza,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Joao Pedro Pinheiro,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Antonio Vilela Pereira,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Pedro G Mercadante,Sergio F Novaes,Breno Orzari,Sandra Padula,Aleksandar Aleksandrov,Georgy Antchev,Roumyana Hadjiiska,Plamen Iaydjiev,Milena Misheva,Mariana Shopova,Georgi Sultanov,Anton Dimitrov,Leander Litov,Borislav Pavlov,Peicho Petkov,Anton Petrov,Elton Shumka,Sumit Keshri,Shalini Thakur,Tongguang Cheng,Tahir Javaid,Li Yuan,Zhen Hu,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor,Hongbo Liao,Zhenan Liu,Ramkrishna Sharma,Jia-Ning Song,Junquan Tao

Published Date

2024/1/17

Ultrarelativistic nuclear collisions create a strongly interacting state of hot and dense quark-gluon matter that exhibits a remarkable collective flow behavior with minimal viscous dissipation. To gain deeper insights into its intrinsic nature and fundamental degrees of freedom, we extracted the speed of sound in this medium created using lead-lead (PbPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data were recorded by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 0.607 nb. The measurement is performed by studying the multiplicity dependence of the average transverse momentum of charged particles emitted in head-on PbPb collisions. Our findings reveal that the speed of sound in this matter is nearly half the speed of light, with a squared value of 0.241 0.002 (stat) 0.016 (syst) in natural units. The effective medium temperature, estimated using the mean transverse momentum, is 219 8 (syst) MeV. The measured squared speed of sound at this temperature aligns precisely with predictions from lattice quantum chromodynamic (QCD) calculations. This result provides a stringent constraint on the equation of state of the created medium and direct evidence for a deconfined QCD phase being attained in relativistic nuclear collisions.

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