Michail Bachtis

University of California, Los Angeles

H-index: 220

North America-United States

About Michail Bachtis

Michail Bachtis, With an exceptional h-index of 220 and a recent h-index of 133 (since 2020), a distinguished researcher at University of California, Los Angeles, specializes in the field of Particle Physics.

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

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

Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC

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

Search for heavy neutral leptons in final states with electrons, muons, and hadronically decaying tau leptons in proton-proton collisions at 13 TeV

Search for the decay of the Higgs boson to a pair of light pseudoscalar bosons in the final state with four bottom quarks in proton-proton collisions at = 13 TeV

Searches for Higgs boson production through decays of heavy resonances

Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at s= 13TeV

Luminosity determination using Z boson production at the CMS experiment

Michail Bachtis Information

University	University of California, Los Angeles
Position	Assistant Professor
Citations(all)	203417
Citations(since 2020)	89165
Cited By	130315
hIndex(all)	220
hIndex(since 2020)	133
i10Index(all)	1001
i10Index(since 2020)	892
Email	Access Email
University Profile Page	University of California, Los Angeles

Michail Bachtis Skills & Research Interests

Particle Physics

Top articles of Michail Bachtis

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.

Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC

Authors

Georges Aad,B Abbott,Kira Abeling,Nils Julius Abicht,SH Abidi,Asmaa Aboulhorma,Halina Abramowicz,Henso Abreu,Yiming Abulaiti,Bobby Samir Acharya,C Adam Bourdarios,L Adamczyk,L Adamek,SV Addepalli,MJ Addison,J Adelman,Aytül Adiguzel,T Adye,AA Affolder,Y Afik,MN Agaras,J Agarwala,A Aggarwal,C Agheorghiesei,A Ahmad,F Ahmadov,WS Ahmed,S Ahuja,X Ai,G Aielli,A Aikot,M Ait Tamlihat,B Aitbenchikh,I Aizenberg,M Akbiyik,TPA Åkesson,AV Akimov,D Akiyama,NN Akolkar,K Al Khoury,GL Alberghi,J Albert,P Albicocco,GL Albouy,S Alderweireldt,M Aleksa,IN Aleksandrov,C Alexa,T Alexopoulos,F Alfonsi,M Algren,M Alhroob,B Ali,HMJ Ali,S Ali,SW Alibocus,M Aliev,G Alimonti,W Alkakhi,C Allaire,BMM Allbrooke,JF Allen,CA Allendes Flores,PP Allport,A Aloisio,F Alonso,C Alpigiani,M Alvarez Estevez,A Alvarez Fernandez,M Alves Cardoso,MG Alviggi,M Aly,Y Amaral Coutinho,A Ambler,C Amelung,M Amerl,CG Ames,D Amidei,SP Amor Dos Santos,KR Amos,V Ananiev,C Anastopoulos,T Andeen,JK Anders,SY Andrean,A Andreazza,S Angelidakis,A Angerami,AV Anisenkov,A Annovi,C Antel,MT Anthony,E Antipov,M Antonelli,F Anulli,M Aoki,T Aoki,JA Aparisi Pozo,MA Aparo,L Aperio Bella,C Appelt,A Apyan,N Aranzabal,C Arcangeletti,ATH Arce,E Arena,JF Arguin,S Argyropoulos,JH Arling,O Arnaez,H Arnold,G Artoni,H Asada,K Asai,S Asai,NA Asbah,J Assahsah,K Assamagan,R Astalos,S Atashi,RJ Atkin,M Atkinson,H Atmani,PA Atmasiddha,K Augsten,S Auricchio,AD Auriol,VA Austrup,G Avolio,K Axiotis,G Azuelos,D Babal,H Bachacou,K Bachas,A Bachiu,F Backman,A Badea,P Bagnaia,M Bahmani,AJ Bailey,VR Bailey,JT Baines,L Baines,C Bakalis,OK Baker,E Bakos,D Bakshi Gupta,V Balakrishnan,R Balasubramanian,EM Baldin

Journal

Physical review letters

Published Date

2024/1/11

The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140 fb− 1 for each experiment, at a center-of-mass energy of 13 TeV. The measured signal yield is 2.2±0.7 times the standard model prediction, and agrees with the theoretical expectation within 1.9 standard deviations.

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 …

Search for heavy neutral leptons in final states with electrons, muons, and hadronically decaying tau leptons 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,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,Konstantin Sharko,Hans Reithler,Austin Baty,Soumya Mukherjee,Tomas Lindén,Jonathon Langford,Graham Wilson,William Tabb,Elena Popova,Furkan Dolek,Attilio Santocchia,Sergio Sánchez Navas,Manuel Calderon De La Barca Sanchez,Wolfram Dietrich Zeuner,Manuel Rodriguez,Jithin Madhusudanan Sreekala,Raphael Granier de Cassagnac,Georgios Daskalakis,Axel Buchot Perraguin,Andrés Abreu,Ernesto Migliore,Alexander Zotz,Tilman Rohe,Paul Schütze,Leonidas Paizanos,Salvatore Nuzzo,Grace Cummings,Yasser Assran,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,Di Wang,Daria Selivanova,Klitos Savva,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,Kimmo Tuomas Samuli Kallonen,Olena Karacheban,Alicia Calderon,Tyler Lam,Kevin Black,Thomas Kress,Georgia Karapostoli,Samuel Lascio,Anusree Vijay,Andrea Claudio Maria Bulla,Berkan Kaynak,Wei Wei,Achille Petrilli,Diogo Bastos,Bhargav Madhusudan Joshi,Abhishikth Mallampalli,Chenfeng Lu,Maria Cepeda,Mauricio Thiel,J William Gary,Dylan Blend,Cécile Caillol,Yannik Rath,Krisztina Márton,Nihar Ranjan Saha,Orgho Neogi,Mohammed Mahmoud,Peicho Petkov,John Rotter,Davide Piccolo,Emanuel Pfeffer,Florian Rehm,Pawel de Barbaro,Vaia Papadimitriou,Robert White,Zhengchen Liang,Nural Akchurin

Journal

arXiv preprint arXiv:2403.00100

Published Date

2024/3/1

A search for heavy neutral leptons (HNLs) of Majorana or Dirac type using protonproton collision data at√ s= 13 TeV is presented. The data were collected by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 138 fb− 1. Events with three charged leptons (electrons, muons, and hadronically decaying tau leptons) are selected, corresponding to HNL production in association with a charged lepton and decay of the HNL to two charged leptons and a standard model (SM) neutrino. The search is performed for HNL masses between 10 GeV and 1.5 TeV. No evidence for an HNL signal is observed in data. Upper limits at 95% confidence level are found for the squared coupling strength of the HNL to SM neutrinos, considering exclusive coupling of the HNL to a single SM neutrino generation, for both Majorana and Dirac HNLs. The limits exceed previously achieved experimental constraints for a wide range of HNL masses, and the limits on tau neutrino coupling scenarios with HNL masses above the W boson mass are presented for the first time.

Search for the decay of the Higgs boson to a pair of light pseudoscalar bosons in the final state with four bottom quarks 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,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,Zebing Wang

Journal

arXiv preprint arXiv:2403.10341

Published Date

2024/3/20

A search is presented for the decay of the 125 GeV Higgs boson (H) to a pair of new light pseudoscalar bosons (a), followed by the prompt decay of each a boson to a bottom quark-antiquark pair, H aa . The analysis is performed using a data sample of proton-proton collisions collected with the CMS detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb. To reduce the background from standard model processes, the search requires the Higgs boson to be produced in association with a leptonically decaying W or Z boson. The analysis probes the production of new light bosons in a 15 60 GeV mass range. Assuming the standard model predictions for the Higgs boson production cross sections for pp WH and ZH, model independent upper limits at 95% confidence level are derived for the branching fraction (H aa ). The combined WH and ZH observed upper limit on the branching fraction ranges from 1.10 for 20 GeV to 0.36 for 60 GeV, complementing other measurements in the , and bb ( ,) channels.

Searches for Higgs boson production through decays of heavy resonances

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,Nordin Breugelmans,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Felix Heyen,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,Gul Gokbulut,Yanwen Hong,Joscha Knolle,Luka Lambrecht,David Marckx,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,Jerome de Favereau de Jeneret,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Ahmet Oguz Guzel,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,Antonio Vilela Pereira,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,Matheus Macedo,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Joao Pedro Pinheiro,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Isabela Maietto Silverio,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,Zhengchen Liang,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang,Anshul Kapoor

Published Date

2024/4/2

The discovery of the Higgs boson has led to new possible signatures for heavy resonance searches at the LHC. Since then, search channels including at least one Higgs boson plus another particle have formed an important part of the program of new physics searches. In this report, the status of these searches by the CMS Collaboration is reviewed. Searches are discussed for resonances decaying to two Higgs bosons, a Higgs and a vector boson, or a Higgs boson and another new resonance, with proton-proton collision data collected at = 13 TeV in the years 2016-2018. A combination of the results of these searches is presented together with constraints on different beyond-the-standard model scenarios, including scenarios with extended Higgs sectors, heavy vector bosons and extra dimensions. Studies are shown for the first time by CMS on the validity of the narrow-width approximation in searches for the resonant production of a pair of Higgs bosons. The potential for a discovery at the High Luminosity LHC is also discussed.

Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at s= 13TeV

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,J van der Linden,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

Journal

Physics Letters B

Published Date

2024/2/2

A search is presented for new Higgs bosons in proton-proton (pp) collision events in which a same-sign top quark pair is produced in association with a jet, via the pp→ tH∕ A→ ttc and pp→ tH∕ A→ ttu processes. Here, H and A represent the extra scalar and pseudoscalar boson, respectively, of the second Higgs doublet in the generalized two-Higgs-doublet model (g2HDM). The search is based on pp collision data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb− 1. Final states with a same-sign lepton pair in association with jets and missing transverse momentum are considered. New Higgs bosons in the 200–1000GeV mass range and new Yukawa couplings between 0.1 and 1.0 are targeted in the search, for scenarios in which either H or A appear alone, or in which they coexist and interfere. No significant excess above the standard model prediction is observed. Exclusion limits are derived in the context of the g2HDM.

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 …

Search for exotic decays of the Higgs boson to a pair of pseudoscalars in the and 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.

Search for dark matter particles in W+W− events with transverse momentum imbalance in proton-proton collisions at = 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,C-E 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 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,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,Z-A Liu,F Monti,R Sharma,JN Song,J Tao

Journal

Journal of High Energy Physics

Published Date

2024/3

A search for dark matter particles is performed using events with a pair of W bosons and large missing transverse momentum. Candidate events are selected by requiring one or two leptons (ℓ= electrons or muons). The analysis is based on proton-proton collision data collected at a center-of-mass energy of 13 TeV by the CMS experiment at the LHC and corresponding to an integrated luminosity of 138 fb− 1. No significant excess over the expected standard model background is observed in the ℓνqq and 2ℓ2ν final states of the W+ W− boson pair. Limits are set on dark matter production in the context of a simplified dark Higgs model, with a dark Higgs boson mass above the W+ W− mass threshold. The dark matter phase space is probed in the mass range 100–300 GeV, extending the scope of previous searches. Current exclusion limits are improved in the range of dark Higgs masses from 160 to 250 GeV, for a dark …

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.

Enriching the physics program of the CMS experiment via data scouting and data parking

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,Nordin Breugelmans,Jorgen d'Hondt,Soumya Dansana,Alexandre de Moor,Martin Delcourt,Felix Heyen,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,Muhammad Aamir Shahzad,Laurent Thomas,Max Vanden Bemden,Pascal Vanlaer,Maarten de Coen,Didar Dobur,Gul Gokbulut,Yanwen Hong,Joscha Knolle,Luka Lambrecht,David Marckx,Gianny Mestdach,Kevin Mota Amarilo,Amrutha Samalan,Kirill Skovpen,Niels van den Bossche,Jan van der Linden,Liam Wezenbeek,Anna Benecke,Agni Bethani,Giacomo Bruno,Claudio Caputo,Jerome de Favereau de Jeneret,Christophe Delaere,Izzeddin Suat Donertas,Andrea Giammanco,Ahmet Oguz Guzel,Sandhya Jain,Vincent Lemaitre,Jindrich Lidrych,Paola Mastrapasqua,Tu Thong Tran,Sébastien Wertz,Gilvan Alves,Miguel Alves Gallo Pereira,Eduardo Coelho,Gilson Correia Silva,Carsten Hensel,Thales Menezes de Oliveira,Arthur Moraes,Patricia Rebello Teles,Mariana Soeiro,Antonio Vilela Pereira,Walter Luiz Aldá Júnior,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,Matheus Macedo,Jordan Martins,Clemencia Mora Herrera,Luiz Mundim,Helio Nogima,Joao Pedro Pinheiro,Alberto Santoro,Andre Sznajder,Mauricio Thiel,Cesar Augusto Bernardes,Luigi Calligaris,Thiago Tomei,Eduardo de Moraes Gregores,Isabela Maietto Silverio,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,Zhengchen Liang,Jinfeng Liu,Kai Yi,Guo-Ming Chen,He-Sheng Chen,Mingshui Chen,Fabio Iemmi,Chun-Hua Jiang

Published Date

2024/4/2

Specialized data-taking and data-processing techniques were introduced by the CMS experiment in Run 1 of the CERN LHC to enhance the sensitivity of searches for new physics and the precision of standard model measurements. These techniques, termed data scouting and data parking, extend the data-taking capabilities of CMS beyond the original design specifications. The novel data-scouting strategy trades complete event information for higher event rates, while keeping the data bandwidth within limits. Data parking involves storing a large amount of raw detector data collected by algorithms with low trigger thresholds to be processed when sufficient computational power is available to handle such data. The research program of the CMS Collaboration is greatly expanded with these techniques. The implementation, performance, and physics results obtained with data scouting and data parking in CMS over the last decade are discussed in this Report, along with new developments aimed at further improving low-mass physics sensitivity over the next years of data taking.

Performance of CMS muon reconstruction from proton-proton to heavy ion collisions

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,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,Jan van der Linden,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,Raphael Gomes de Souza,Jordan Martins,Clemencia Mora Herrera,Kevin Mota Amarilo,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,Emilien Chapon,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:2404.17377

Published Date

2024/4/29

The performance of muon tracking, identification, triggering, momentum resolution, and momentum scale has been studied with the CMS detector at the LHC using data collected at = 5.02 TeV in proton-proton (pp) and lead-lead (PbPb) collisions in 2017 and 2018, respectively, and at = 8.16 TeV in proton-lead (pPb) collisions in 2016. Muon efficiencies, momentum resolutions, and momentum scales are compared by focusing on how the muon reconstruction performance varies from relatively small occupancy pp collisions to the larger occupancies of pPb collisions and, finally, to the highest track multiplicity PbPb collisions. We find the efficiencies of muon tracking, identification, and triggering to be above 90% throughout most of the track multiplicity range. The momentum resolution and scale are unaffected by the detector occupancy. The excellent muon reconstruction of the CMS detector enables precision studies across all available collision systems.

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.

Measurement of the τ lepton polarization in Z boson decays 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,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,C-E 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,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 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,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,Z-A Liu,F Monti,R Sharma,JN Song,J Tao

Journal

Journal of High Energy Physics

Published Date

2024/1

The polarization of τ leptons is measured using leptonic and hadronic τ lepton decays in Z→ τ+ τ− events in proton-proton collisions at= 13 TeV recorded by CMS at the CERN LHC with an integrated luminosity of 36.3 fb− 1. The measured τ− lepton polarization at the Z boson mass pole is=− 0.144±0.006 (stat)±0.014 (syst)=− 0.144±0.015, in good agreement with the measurement of the τ lepton asymmetry parameter of A τ= 0.1439±0.0043= at LEP. The τ lepton polarization depends on the ratio of the vector to axial-vector couplings of the τ leptons in the neutral current expression, and thus on the effective weak mixing angle sin 2, independently of the Z boson production mechanism. The obtained value sin 2= 0.2319±0. 0008 (stat)±0. 0018 (syst)= 0. 2319±0. 0019 is in good agreement with measurements at e+ e− colliders.

Search for long-lived particles decaying to final states with a pair of muons in proton-proton collisions at = 13.6 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.

Observation of the decay and studies of the baryon 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,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,Konstantin Sharko,Hans Reithler,Austin Baty,Soumya Mukherjee,Tomas Lindén,Jonathon Langford,Graham Wilson,William Tabb,Elena Popova,Furkan Dolek,Attilio Santocchia,Sergio Sánchez Navas,Manuel Calderon De La Barca Sanchez,Wolfram Dietrich Zeuner,Manuel Rodriguez,Jithin Madhusudanan Sreekala,Raphael Granier de Cassagnac,Georgios Daskalakis,Axel Buchot Perraguin,Andrés Abreu,Ernesto Migliore,Alexander Zotz,Tilman Rohe,Paul Schütze,Leonidas Paizanos,Salvatore Nuzzo,Grace Cummings,Yasser Assran,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,Klitos Savva,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,Kimmo Tuomas Samuli Kallonen,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,J William Gary,Dylan Blend,Cécile Caillol,Yannik Rath,Krisztina Márton,Nihar Ranjan Saha,Orgho Neogi,Mohammed Mahmoud,Peicho Petkov,John Rotter,Davide Piccolo,Emanuel Pfeffer,Florian Rehm,Pawel de Barbaro,Vaia Papadimitriou,Robert White,Nural Akchurin,Patrice Verdier,Reham Aly,Vincenzo Innocente

Published Date

2024/2/28

The\Xbsd decay topology, where the\Xb baryon decays to\psiXim with $\PGy\to\mumu $(upper) or\jpsiLaKm (lower), where\PGy refers to the\jpsi and\psit mesons. The distances given are the average decay lengths, .The\Xbsd decay topology, where the\Xb baryon decays to\psiXim with $\PGy\to\mumu $(upper) or\jpsiLaKm (lower), where\PGy refers to the\jpsi and\psit mesons. The distances given are the average decay lengths, .

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.

The CMS statistical analysis and combination tool: COMBINE

Authors

Aram Hayrapetyan

Published Date

2024/4/9

This paper describes the COMBINE software package used for statistical analyses by the CMS Collaboration. The package, originally designed to perform searches for a Higgs boson and the combined analysis of those searches, has evolved to become the statistical analysis tool presently used in the majority of measurements and searches performed by the CMS Collaboration. It is not specific to the CMS experiment, and this paper is intended to serve as a reference for users outside of the CMS Collaboration, providing an outline of the most salient features and capabilities. Readers are provided with the possibility to run COMBINE and reproduce examples provided in this paper using a publicly available container image. Since the package is constantly evolving to meet the demands of ever-increasing data sets and analysis sophistication, this paper cannot cover all details of COMBINE. However, the online documentation referenced within this paper provides an up-to-date and complete user guide.

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.

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