Ekmedžić, Marko

TY  - JOUR
AU  - Chatrchyan, S.
AU  - Adžić, Petar
AU  - Đorđević, Miloš
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Milenović, Predrag
AU  - Rekovic, V.
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1617
AB  - The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark (Delta m(t) = m(t) - m((t) over bar)) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and at least four jets in the final state. The analysis is based on data corresponding to an integrated luminosity of 19.6 fb(-1) collected by the CMS experiment at the LHC, and yields a value of Delta m(t) = 0.15 0.19 (stat) +/- 0.09(syst) GeV, which is consistent with the SM expectation. This result is significantly more precise than previously reported measurements. (C) 2017 The Author(s). Published by Elsevier B.V.
T2  - Physics Letters B
T1  - Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV
VL  - 770
SP  - 50
EP  - 71
DO  - 10.1016/j.physletb.2017.04.028
ER  - 

@article{
author = "Chatrchyan, S. and Adžić, Petar and Đorđević, Miloš and Ekmedzic, M. and Milošević, Jovan and Milenović, Predrag and Rekovic, V.",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1617",
abstract = "The invariance of the standard model (SM) under the CPT transformation predicts equality of particle and antiparticle masses. This prediction is tested by measuring the mass difference between the top quark and antiquark (Delta m(t) = m(t) - m((t) over bar)) that are produced in pp collisions at a center-of-mass energy of 8 TeV, using events with a muon or an electron and at least four jets in the final state. The analysis is based on data corresponding to an integrated luminosity of 19.6 fb(-1) collected by the CMS experiment at the LHC, and yields a value of Delta m(t) = 0.15 0.19 (stat) +/- 0.09(syst) GeV, which is consistent with the SM expectation. This result is significantly more precise than previously reported measurements. (C) 2017 The Author(s). Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV",
volume = "770",
pages = "50-71",
doi = "10.1016/j.physletb.2017.04.028"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/898
AB  - The production cross sections of the B+, B-0, and B-s(0) mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p + Pb collisions at the center-of-mass energy root s(NN) = 5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nb(-1). The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb + Pb collisions.
T2  - Physical Review Letters
T1  - Study of B Meson Production in p plus Pb Collisions at root s(NN)=5.02 TeV Using Exclusive Hadronic Decays
VL  - 116
IS  - 3
DO  - 10.1103/PhysRevLett.116.032301
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/898",
abstract = "The production cross sections of the B+, B-0, and B-s(0) mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p + Pb collisions at the center-of-mass energy root s(NN) = 5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nb(-1). The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb + Pb collisions.",
journal = "Physical Review Letters",
title = "Study of B Meson Production in p plus Pb Collisions at root s(NN)=5.02 TeV Using Exclusive Hadronic Decays",
volume = "116",
number = "3",
doi = "10.1103/PhysRevLett.116.032301"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adzic, R.
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/907
AB  - A search is presented for exotic decays of a Higgs boson into undetectable particles and one or two isolated photons in pp collisions at a center-of-mass energy of 8 TeV. The data correspond to an integrated luminosity of up to 19.4 fb(-1) collected with the CMS detector at the LHC. Higgs bosons produced in gluon-gluon fusion and in association with a Z boson are investigated, using models in which the Higgs boson decays into a gravitino and a neutralino or a pair of neutralinos, followed by the decay of the neutralino to a gravitino and a photon. The selected events are consistent with the background-only hypothesis, and limits are placed on the product of cross sections and branching fractions. Assuming a standard model Higgs boson production cross section, a 95% confidence level upper limit is set on the branching fraction of a 125 GeV Higgs boson decaying into undetectable particles and one or two isolated photons as a function of the neutralino mass. For this class of models and neutralino masses from 1 to 120 GeV an upper limit in the range of 7 to 13% is obtained. Further results are given as a function of the neutralino lifetime, and also for a range of Higgs boson masses. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
T2  - Physics Letters B
T1  - Search for exotic decays of a Higgs boson into undetectable particles and one or more photons
VL  - 753
SP  - 363
EP  - 388
DO  - 10.1016/j.physletb.2015.12.017
ER  - 

@article{
author = "Khachatryan, V. and Adzic, R. and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/907",
abstract = "A search is presented for exotic decays of a Higgs boson into undetectable particles and one or two isolated photons in pp collisions at a center-of-mass energy of 8 TeV. The data correspond to an integrated luminosity of up to 19.4 fb(-1) collected with the CMS detector at the LHC. Higgs bosons produced in gluon-gluon fusion and in association with a Z boson are investigated, using models in which the Higgs boson decays into a gravitino and a neutralino or a pair of neutralinos, followed by the decay of the neutralino to a gravitino and a photon. The selected events are consistent with the background-only hypothesis, and limits are placed on the product of cross sections and branching fractions. Assuming a standard model Higgs boson production cross section, a 95% confidence level upper limit is set on the branching fraction of a 125 GeV Higgs boson decaying into undetectable particles and one or two isolated photons as a function of the neutralino mass. For this class of models and neutralino masses from 1 to 120 GeV an upper limit in the range of 7 to 13% is obtained. Further results are given as a function of the neutralino lifetime, and also for a range of Higgs boson masses. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).",
journal = "Physics Letters B",
title = "Search for exotic decays of a Higgs boson into undetectable particles and one or more photons",
volume = "753",
pages = "363-388",
doi = "10.1016/j.physletb.2015.12.017"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adzic, R.
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1106
AB  - The consistency of the spin correlation strength in top quark pair production with the standard model (SM) prediction is tested in the muon+jets final state. The events are selected from pp collisions, collected by the CMS detector, at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The data are compared with the expectation for the spin correlation predicted by the SM and with the expectation of no correlation. Using a template fit method, the fraction of events that show SM spin correlations is measured to be 0.72 0.08 (stat)(-013)(+015) (syst), representing the most precise measurement of this quantity in the muon+jets final state to date. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.orglicenses/by/4.01).
T2  - Physics Letters B
T1  - Measurement of spin correlations in tf production using the matrix element method in the muon plus jets final state in pp collisions at root S=8 TeV
VL  - 758
SP  - 321
EP  - 346
DO  - 10.1016/j.physletb.2016.05.005
ER  - 

@article{
author = "Khachatryan, V. and Adzic, R. and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1106",
abstract = "The consistency of the spin correlation strength in top quark pair production with the standard model (SM) prediction is tested in the muon+jets final state. The events are selected from pp collisions, collected by the CMS detector, at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The data are compared with the expectation for the spin correlation predicted by the SM and with the expectation of no correlation. Using a template fit method, the fraction of events that show SM spin correlations is measured to be 0.72 0.08 (stat)(-013)(+015) (syst), representing the most precise measurement of this quantity in the muon+jets final state to date. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.orglicenses/by/4.01).",
journal = "Physics Letters B",
title = "Measurement of spin correlations in tf production using the matrix element method in the muon plus jets final state in pp collisions at root S=8 TeV",
volume = "758",
pages = "321-346",
doi = "10.1016/j.physletb.2016.05.005"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/997
AB  - A search for a heavy scalar boson H decaying into a pair of lighter standard-model-like 125 GeV Higgs bosons hh and a search for a heavy pseudoscalar boson A decaying into a Z and an h boson are presented. The searches are performed on a data set corresponding to an integrated luminosity of 19.7 fb(-1) of pp collision data at a centre-of-mass energy of 8 TeV, collected by CMS in 2012. A final state consisting of two tau leptons and two b jets is used to search for the H - GT hh decay. A final state consisting of two tau leptons from the h boson decay, and two additional leptons from the Z boson decay, is used to search for the decay A - GT Zh. The results are interpreted in the context of two-Higgs-doublet models. No excess is found above the standard model expectation and upper limits are set on the heavy boson production cross sections in the mass ranges 260 LT m(H) LT 350 GeV and 220 LT m(A) LT 350 GeV. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
T2  - Physics Letters B
T1  - Searches for a heavy scalar boson H decaying to a pair of 125 GeV Higgs bosons hh or for a heavy pseudoscalar boson A decaying to Zh, in the final states with h - GT tau tau
VL  - 755
SP  - 217
EP  - 244
DO  - 10.1016/j.physletb.2016.01.056
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/997",
abstract = "A search for a heavy scalar boson H decaying into a pair of lighter standard-model-like 125 GeV Higgs bosons hh and a search for a heavy pseudoscalar boson A decaying into a Z and an h boson are presented. The searches are performed on a data set corresponding to an integrated luminosity of 19.7 fb(-1) of pp collision data at a centre-of-mass energy of 8 TeV, collected by CMS in 2012. A final state consisting of two tau leptons and two b jets is used to search for the H - GT hh decay. A final state consisting of two tau leptons from the h boson decay, and two additional leptons from the Z boson decay, is used to search for the decay A - GT Zh. The results are interpreted in the context of two-Higgs-doublet models. No excess is found above the standard model expectation and upper limits are set on the heavy boson production cross sections in the mass ranges 260 LT m(H) LT 350 GeV and 220 LT m(A) LT 350 GeV. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "Searches for a heavy scalar boson H decaying to a pair of 125 GeV Higgs bosons hh or for a heavy pseudoscalar boson A decaying to Zh, in the final states with h - GT tau tau",
volume = "755",
pages = "217-244",
doi = "10.1016/j.physletb.2016.01.056"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/882
AB  - A search is performed for the production of heavy resonances decaying into top-antitop quark pairs in proton-proton collisions at root s = 8 TeV. Data used for the analyses were collected with the CMS detector and correspond to an integrated luminosity of 19.7 fb(-1). The search is performed using events with three different final states, defined by the number of leptons (electrons and muons) from the t (t) over bar. WbWb decay. The analyses are optimized for reconstruction of top quarks with high Lorentz boosts, where jet substructure techniques are used to enhance the sensitivity. Results are presented for all channels and a combination is performed. No significant excess of events relative to the expected yield from standard model processes is observed. Upper limits on the production cross section of heavy resonances decaying to t (t) over bar are calculated. A narrow leptophobic topcolor Z resonance with a mass below 2.4 TeV is excluded at 95% confidence level. Limits are also derived for a broad Z resonance with a 10% width relative to the resonance mass, and a Kaluza-Klein excitation of the gluon in the Randall-Sundrum model. These are the most stringent limits to date on heavy resonances decaying into top-antitop quark pairs.
T2  - Physical Review D
T1  - Search for resonant t(t)over-bar production in proton-proton collisions at root s=8 TeV
VL  - 93
IS  - 1
DO  - 10.1103/PhysRevD.93.012001
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/882",
abstract = "A search is performed for the production of heavy resonances decaying into top-antitop quark pairs in proton-proton collisions at root s = 8 TeV. Data used for the analyses were collected with the CMS detector and correspond to an integrated luminosity of 19.7 fb(-1). The search is performed using events with three different final states, defined by the number of leptons (electrons and muons) from the t (t) over bar. WbWb decay. The analyses are optimized for reconstruction of top quarks with high Lorentz boosts, where jet substructure techniques are used to enhance the sensitivity. Results are presented for all channels and a combination is performed. No significant excess of events relative to the expected yield from standard model processes is observed. Upper limits on the production cross section of heavy resonances decaying to t (t) over bar are calculated. A narrow leptophobic topcolor Z resonance with a mass below 2.4 TeV is excluded at 95% confidence level. Limits are also derived for a broad Z resonance with a 10% width relative to the resonance mass, and a Kaluza-Klein excitation of the gluon in the Randall-Sundrum model. These are the most stringent limits to date on heavy resonances decaying into top-antitop quark pairs.",
journal = "Physical Review D",
title = "Search for resonant t(t)over-bar production in proton-proton collisions at root s=8 TeV",
volume = "93",
number = "1",
doi = "10.1103/PhysRevD.93.012001"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/951
AB  - A search is presented for the production of both first- and second-generation scalar leptoquarks with a final state of either two electrons and one jet or two muons and one jet. The search is based on a data sample of proton-proton collisions at center-of-mass energy root s = 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb(-1). Upper limits are set on both the first- and second-generation leptoquark production cross sections as functions of the leptoquark mass and the leptoquark couplings to a lepton and a quark. Results are compared with theoretical predictions to obtain lower limits on the leptoquark mass. At 95% confidence level, single production of first- generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 1730 GeV, and second-generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 530 GeV. These are the best overall limits on the production of first-generation leptoquarks to date.
T2  - Physical Review D
T1  - Search for single production of scalar leptoquarks in proton-proton collisions at root s=8 TeV
VL  - 93
IS  - 3
DO  - 10.1103/PhysRevD.93.032005
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/951",
abstract = "A search is presented for the production of both first- and second-generation scalar leptoquarks with a final state of either two electrons and one jet or two muons and one jet. The search is based on a data sample of proton-proton collisions at center-of-mass energy root s = 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb(-1). Upper limits are set on both the first- and second-generation leptoquark production cross sections as functions of the leptoquark mass and the leptoquark couplings to a lepton and a quark. Results are compared with theoretical predictions to obtain lower limits on the leptoquark mass. At 95% confidence level, single production of first- generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 1730 GeV, and second-generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 530 GeV. These are the best overall limits on the production of first-generation leptoquarks to date.",
journal = "Physical Review D",
title = "Search for single production of scalar leptoquarks in proton-proton collisions at root s=8 TeV",
volume = "93",
number = "3",
doi = "10.1103/PhysRevD.93.032005"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/888
AB  - search for neutral Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) for mu(+) mu(-) decay channels is presented. The analysis uses data collected by the CMS experiment at the LHC in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.3 fb(-1), respectively. The search is sensitive to Higgs bosons produced either through the gluon fusion process or in association with a b (b) over bar quark pair. No statistically significant excess is observed in the mu(+) mu(-) mass spectrum. Results are interpreted in the framework of several benchmark scenarios, and the data are used to set an upper limit on the MSSM parameter tan beta as a function of the mass of the pseudoscalar A boson in the range from 115 to 300 GeV. Model independent upper limits are given for the product of the cross section and branching fraction for gluon fusion and b quark associated production at root s = 8 TeV. They are the most stringent limits obtained to date in this channel. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
T2  - Physics Letters B
T1  - Search for neutral MSSM Higgs bosons decaying to mu(+) mu(-) in pp collisions at root s=7 and 8 TeV
VL  - 752
SP  - 221
EP  - 246
DO  - 10.1016/j.physletb.2015.11.042
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/888",
abstract = "search for neutral Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) for mu(+) mu(-) decay channels is presented. The analysis uses data collected by the CMS experiment at the LHC in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.3 fb(-1), respectively. The search is sensitive to Higgs bosons produced either through the gluon fusion process or in association with a b (b) over bar quark pair. No statistically significant excess is observed in the mu(+) mu(-) mass spectrum. Results are interpreted in the framework of several benchmark scenarios, and the data are used to set an upper limit on the MSSM parameter tan beta as a function of the mass of the pseudoscalar A boson in the range from 115 to 300 GeV. Model independent upper limits are given for the product of the cross section and branching fraction for gluon fusion and b quark associated production at root s = 8 TeV. They are the most stringent limits obtained to date in this channel. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "Search for neutral MSSM Higgs bosons decaying to mu(+) mu(-) in pp collisions at root s=7 and 8 TeV",
volume = "752",
pages = "221-246",
doi = "10.1016/j.physletb.2015.11.042"
}

@misc{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1309",
journal = "Journal of High Energy Physics",
title = "Search for third-generation scalar leptoquarks in the t tau channel in proton-proton collisions at root s = 8 TeV (vol 7, 042, 2015)",
number = "11",
doi = "10.1007/JHEP11(2016)056"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/943
AB  - Measurements of the cross sections for top quark pairs produced in association with a W or Z boson are presented, using 8 TeV pp collision data corresponding to an integrated luminosity of 19.5 fb(-1), collected by the CMS experiment at the LHC. Final states are selected in which the associated W boson decays to a charged lepton and a neutrino or the Z boson decays to two charged leptons. Signal events are identified by matching reconstructed objects in the detector to specific final state particles from t (t) over barW or t (t) over barZ decays. The t (t) over barW cross section is measured to be 382(-102)(+117) fb with a significance of 4.8 standard deviations from the background-only hypothesis. The t (t) over barZ cross section is measured to be 242(-55)(+65) fb with a significance of 6.4 standard deviations from the background-only hypothesis. These measurements are used to set bounds on five anomalous dimension-six operators that would affect the t (t) over barW and t (t) over barZ cross sections.
T2  - Journal of High Energy Physics
T1  - Observation of top quark pairs produced in association with a vector boson in pp collisions at root s=8 TeV
IS  - 1
DO  - 10.1007/JHEP01(2016)096
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/943",
abstract = "Measurements of the cross sections for top quark pairs produced in association with a W or Z boson are presented, using 8 TeV pp collision data corresponding to an integrated luminosity of 19.5 fb(-1), collected by the CMS experiment at the LHC. Final states are selected in which the associated W boson decays to a charged lepton and a neutrino or the Z boson decays to two charged leptons. Signal events are identified by matching reconstructed objects in the detector to specific final state particles from t (t) over barW or t (t) over barZ decays. The t (t) over barW cross section is measured to be 382(-102)(+117) fb with a significance of 4.8 standard deviations from the background-only hypothesis. The t (t) over barZ cross section is measured to be 242(-55)(+65) fb with a significance of 6.4 standard deviations from the background-only hypothesis. These measurements are used to set bounds on five anomalous dimension-six operators that would affect the t (t) over barW and t (t) over barZ cross sections.",
journal = "Journal of High Energy Physics",
title = "Observation of top quark pairs produced in association with a vector boson in pp collisions at root s=8 TeV",
number = "1",
doi = "10.1007/JHEP01(2016)096"
}

@misc{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1010",
journal = "Journal of High Energy Physics",
title = "Comparison of the Z/gamma* + jets to gamma + jets cross sections in pp collisions at root s = 8 (vol 10, 128, 2015)",
number = "4",
doi = "10.1007/JHEP04(2016)010"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adzic, R.
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/998
AB  - A measurement of the ratio of the branching fractions of the B-s(0) meson to J/psi f(0)(980) and to J/psi phi(1020) is presented. The J/psi, f(0)(980), and phi(1020) are observed through their decays to mu(+)mu(-), pi(+)pi(-), and K+K-, respectively. The f(0) and the phi are identified by requiring |M-pi+(pi)- - 974 MeV| LT 50 MeV and |M-K+(K)- - 1020 MeV| LT 10 MeV. The analysis is based on a data sample of pp collisions at a centre-of-mass energy of 7 TeV, collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3fb(-1). The measured ratio is B(B-s(0) - GT J/psi f(0)) B(f(0) - GT pi(+)pi(-))/B(B-s(0) - GT J/psi phi) B(phi - GT K+K-)= 0.140 +/- 0.008 (stat) +/- 0.023 (syst), where the first uncertainty is statistical and the second is systematic. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license.
T2  - Physics Letters B
T1  - Measurement of the ratio B(B-s(0) - GT J/psi f(0)(980))/B(B-s(0) - GT J/psi phi(1020)) in pp collisions at root s=7 TeV
VL  - 756
SP  - 84
EP  - 102
DO  - 10.1016/j.physletb.2016.02.047
ER  - 

@article{
author = "Khachatryan, V. and Adzic, R. and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/998",
abstract = "A measurement of the ratio of the branching fractions of the B-s(0) meson to J/psi f(0)(980) and to J/psi phi(1020) is presented. The J/psi, f(0)(980), and phi(1020) are observed through their decays to mu(+)mu(-), pi(+)pi(-), and K+K-, respectively. The f(0) and the phi are identified by requiring |M-pi+(pi)- - 974 MeV| LT 50 MeV and |M-K+(K)- - 1020 MeV| LT 10 MeV. The analysis is based on a data sample of pp collisions at a centre-of-mass energy of 7 TeV, collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3fb(-1). The measured ratio is B(B-s(0) - GT J/psi f(0)) B(f(0) - GT pi(+)pi(-))/B(B-s(0) - GT J/psi phi) B(phi - GT K+K-)= 0.140 +/- 0.008 (stat) +/- 0.023 (syst), where the first uncertainty is statistical and the second is systematic. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license.",
journal = "Physics Letters B",
title = "Measurement of the ratio B(B-s(0) - GT J/psi f(0)(980))/B(B-s(0) - GT J/psi phi(1020)) in pp collisions at root s=7 TeV",
volume = "756",
pages = "84-102",
doi = "10.1016/j.physletb.2016.02.047"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/887
AB  - A search for the pair production of new light bosons, each decaying into a pair of muons, is performed with the CMS experiment at the LHC, using a dataset corresponding to an integrated luminosity of 20.7 fb(-1) collected in proton-proton collisions at center-of-mass energy of root s = 8 TeV. No excess is observed in the data relative to standard model background expectation and a model independent upper limit on the product of the cross section, branching fraction, and acceptance is derived. The results are compared with two benchmark models, the first one in the context of the next-to-minimal super-symmetric standard model, and the second one in scenarios containing a hidden sector, including those predicting a nonnegligible light boson lifetime. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
T2  - Physics Letters B
T1  - A search for pair production of new light bosons decaying into muons
VL  - 752
SP  - 146
EP  - 168
DO  - 10.1016/j.physletb.2015.10.067
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/887",
abstract = "A search for the pair production of new light bosons, each decaying into a pair of muons, is performed with the CMS experiment at the LHC, using a dataset corresponding to an integrated luminosity of 20.7 fb(-1) collected in proton-proton collisions at center-of-mass energy of root s = 8 TeV. No excess is observed in the data relative to standard model background expectation and a model independent upper limit on the product of the cross section, branching fraction, and acceptance is derived. The results are compared with two benchmark models, the first one in the context of the next-to-minimal super-symmetric standard model, and the second one in scenarios containing a hidden sector, including those predicting a nonnegligible light boson lifetime. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "A search for pair production of new light bosons decaying into muons",
volume = "752",
pages = "146-168",
doi = "10.1016/j.physletb.2015.10.067"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1356
AB  - The decorrelation in the azimuthal angle between the most forward and the most backward jets (Mueller-Navelet jets) is measured in data collected in pp collisions with the CMS detector at the LHC at root s = 7 TeV. The measurement is presented in the form of distributions of azimuthal-angle differences, Delta phi, between the Mueller-Navelet jets, the average cosines of (pi - Delta phi), 2(pi - Delta phi), and 3(pi - Delta phi), and ratios of these cosines. The jets are required to have transverse momenta, p(T), in excess of 35 GeV and rapidities, |y|, of less than 4.7. The results are presented as a function of the rapidity separation, Delta y, between the Mueller-Navelet jets, reaching Delta y up to 9.4 for the first time. The results are compared to predictions of various Monte Carlo event generators and to analytical predictions based on the DGLAP and BFKL parton evolution schemes.
T2  - Journal of High Energy Physics
T1  - Azimuthal decorrelation of jets widely separated in rapidity in pp collisions at root s=7 TeV
IS  - 8
DO  - 10.1007/JHEP08(2016)139
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1356",
abstract = "The decorrelation in the azimuthal angle between the most forward and the most backward jets (Mueller-Navelet jets) is measured in data collected in pp collisions with the CMS detector at the LHC at root s = 7 TeV. The measurement is presented in the form of distributions of azimuthal-angle differences, Delta phi, between the Mueller-Navelet jets, the average cosines of (pi - Delta phi), 2(pi - Delta phi), and 3(pi - Delta phi), and ratios of these cosines. The jets are required to have transverse momenta, p(T), in excess of 35 GeV and rapidities, |y|, of less than 4.7. The results are presented as a function of the rapidity separation, Delta y, between the Mueller-Navelet jets, reaching Delta y up to 9.4 for the first time. The results are compared to predictions of various Monte Carlo event generators and to analytical predictions based on the DGLAP and BFKL parton evolution schemes.",
journal = "Journal of High Energy Physics",
title = "Azimuthal decorrelation of jets widely separated in rapidity in pp collisions at root s=7 TeV",
number = "8",
doi = "10.1007/JHEP08(2016)139"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1519
AB  - A measurement of the W boson pair production cross section in proton-proton collisions at root s = 8TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 fb(-1). The W+W- candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured W+W- cross section is 60.1 +/- 0.9 (stat) +/- 3.2 (exp) +/- 3.1 (theo) +/- 1.6 (lumi) pb = 60.1 +/- 4.8 pb, consistent with the standard model prediction. The W+W- cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are -5.7 LT c(WWW)/Lambda(2) LT 5.9TeV(-2), -11.4 LT c(W)/Lambda(2) LT 5.4TeV(-2), -29.2 LT c(B)/Lambda(2) LT 23.9 TeV-2, in the HISZ basis.
T2  - European Physical Journal C. Particles and Fields
T1  - Measurement of the W+W- cross section in pp collisions at root s=8 TeV and limits on anomalous gauge couplings
VL  - 76
IS  - 7
DO  - 10.1140/epjc/s10052-016-4219-1
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1519",
abstract = "A measurement of the W boson pair production cross section in proton-proton collisions at root s = 8TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 fb(-1). The W+W- candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured W+W- cross section is 60.1 +/- 0.9 (stat) +/- 3.2 (exp) +/- 3.1 (theo) +/- 1.6 (lumi) pb = 60.1 +/- 4.8 pb, consistent with the standard model prediction. The W+W- cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are -5.7 LT c(WWW)/Lambda(2) LT 5.9TeV(-2), -11.4 LT c(W)/Lambda(2) LT 5.4TeV(-2), -29.2 LT c(B)/Lambda(2) LT 23.9 TeV-2, in the HISZ basis.",
journal = "European Physical Journal C. Particles and Fields",
title = "Measurement of the W+W- cross section in pp collisions at root s=8 TeV and limits on anomalous gauge couplings",
volume = "76",
number = "7",
doi = "10.1140/epjc/s10052-016-4219-1"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/950
AB  - A search for pair production of first and second generation leptoquarks is performed in final states containing either two charged leptons and two jets, or one charged lepton, one neutrino and two jets, using proton-proton collision data at root s = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were recorded with the CMS detector at the LHC. First-generation scalar leptoquarks with masses less than 1010 (850) GeV are excluded for beta = 1.0 (0.5), where beta is the branching fraction of a leptoquark decaying to a charged lepton and a quark. Similarly, second-generation scalar leptoquarks with masses less than 1080 (760) GeV are excluded for beta = 1.0 (0.5). Mass limits are also set for vector leptoquark production scenarios with anomalous vector couplings, and for R-parity violating supersymmetric scenarios of top squark pair production resulting in similar final-state signatures. These are the most stringent limits placed on the masses of vector leptoquarks and RPV top squarks to date.
T2  - Physical Review D
T1  - Search for pair production of first and second generation leptoquarks in proton-proton collisions at root s=8 TeV
VL  - 93
IS  - 3
DO  - 10.1103/PhysRevD.93.032004
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/950",
abstract = "A search for pair production of first and second generation leptoquarks is performed in final states containing either two charged leptons and two jets, or one charged lepton, one neutrino and two jets, using proton-proton collision data at root s = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were recorded with the CMS detector at the LHC. First-generation scalar leptoquarks with masses less than 1010 (850) GeV are excluded for beta = 1.0 (0.5), where beta is the branching fraction of a leptoquark decaying to a charged lepton and a quark. Similarly, second-generation scalar leptoquarks with masses less than 1080 (760) GeV are excluded for beta = 1.0 (0.5). Mass limits are also set for vector leptoquark production scenarios with anomalous vector couplings, and for R-parity violating supersymmetric scenarios of top squark pair production resulting in similar final-state signatures. These are the most stringent limits placed on the masses of vector leptoquarks and RPV top squarks to date.",
journal = "Physical Review D",
title = "Search for pair production of first and second generation leptoquarks in proton-proton collisions at root s=8 TeV",
volume = "93",
number = "3",
doi = "10.1103/PhysRevD.93.032004"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1048
AB  - A search for a massive resonance decaying into a standard-model-like Higgs boson (H) and a W or Z boson is reported. The analysis is performed on a data sample corresponding to an integrated luminosity of 19.7 fb(-1), collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. Signal events, in which the decay products of Higgs, W, or Z bosons at high Lorentz boost are contained within single reconstructed jets, are identified using jet substructure techniques, including the tagging of b hadrons. This is the first search for heavy resonances decaying into HW or HZ resulting in an all-jet final state, as well as the first application of jet substructure techniques to identify H - GT WW* - GT 4q decays at high Lorentz boost. No significant signal is observed and limits are set at 95% confidence level on the production cross sections of W and Z in a model with mass-degenerate charged and neutral spin-1 resonances. Resonance masses are excluded for W in the interval [1.0, 1.6] TeV, for Z in the intervals [1.0, 1.1] and [1.3, 1.5] TeV, and for mass-degenerate W and Z in the interval [1.0, 1.7] TeV.
T2  - Journal of High Energy Physics
T1  - Search for a massive resonance decaying into a Higgs boson and a W or Z boson in hadronic final states in proton-proton collisions at root s=8 TeV
IS  - 2
DO  - 10.1007/JHEP02(2016)145
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1048",
abstract = "A search for a massive resonance decaying into a standard-model-like Higgs boson (H) and a W or Z boson is reported. The analysis is performed on a data sample corresponding to an integrated luminosity of 19.7 fb(-1), collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. Signal events, in which the decay products of Higgs, W, or Z bosons at high Lorentz boost are contained within single reconstructed jets, are identified using jet substructure techniques, including the tagging of b hadrons. This is the first search for heavy resonances decaying into HW or HZ resulting in an all-jet final state, as well as the first application of jet substructure techniques to identify H - GT WW* - GT 4q decays at high Lorentz boost. No significant signal is observed and limits are set at 95% confidence level on the production cross sections of W and Z in a model with mass-degenerate charged and neutral spin-1 resonances. Resonance masses are excluded for W in the interval [1.0, 1.6] TeV, for Z in the intervals [1.0, 1.1] and [1.3, 1.5] TeV, and for mass-degenerate W and Z in the interval [1.0, 1.7] TeV.",
journal = "Journal of High Energy Physics",
title = "Search for a massive resonance decaying into a Higgs boson and a W or Z boson in hadronic final states in proton-proton collisions at root s=8 TeV",
number = "2",
doi = "10.1007/JHEP02(2016)145"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adzic, R.
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/906
AB  - A search is described for a Higgs boson decaying into two photons, one of which has an internal conversion to a muon or an electron pair (ll gamma). The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at a centre-of-mass energy of 8TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The events selected have an opposite-sign muon or electron pair and a high transverse momentum photon. No excess above background has been found in the three-body invariant mass range 120 LT m(ll gamma) LT 150 GeV, and limits have been derived for the Higgs boson production cross section times branching fraction for the decay H - GT gamma*gamma - GT ll gamma, where the dilepton invariant mass is less than 20 GeV. For a Higgs boson with m(H) = 125 GeV, a 95% confidence level (CL) exclusion observed (expected) limit is 6.7 (5.9(-1.8)(+2.8)) times the standard model prediction. Additionally, an upper limit at 95% CL on the branching fraction of H - GT (J/psi)gamma for the 125 GeV Higgs boson is set at 1.5 x10(-3). (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
T2  - Physics Letters B
T1  - Search for a Higgs boson decaying into gamma*gamma - GT ll gamma with low dilepton mass in pp collisions at root s=8 TeV
VL  - 753
SP  - 341
EP  - 362
DO  - 10.1016/j.physletb.2015.12.039
ER  - 

@article{
author = "Khachatryan, V. and Adzic, R. and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/906",
abstract = "A search is described for a Higgs boson decaying into two photons, one of which has an internal conversion to a muon or an electron pair (ll gamma). The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at a centre-of-mass energy of 8TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The events selected have an opposite-sign muon or electron pair and a high transverse momentum photon. No excess above background has been found in the three-body invariant mass range 120 LT m(ll gamma) LT 150 GeV, and limits have been derived for the Higgs boson production cross section times branching fraction for the decay H - GT gamma*gamma - GT ll gamma, where the dilepton invariant mass is less than 20 GeV. For a Higgs boson with m(H) = 125 GeV, a 95% confidence level (CL) exclusion observed (expected) limit is 6.7 (5.9(-1.8)(+2.8)) times the standard model prediction. Additionally, an upper limit at 95% CL on the branching fraction of H - GT (J/psi)gamma for the 125 GeV Higgs boson is set at 1.5 x10(-3). (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).",
journal = "Physics Letters B",
title = "Search for a Higgs boson decaying into gamma*gamma - GT ll gamma with low dilepton mass in pp collisions at root s=8 TeV",
volume = "753",
pages = "341-362",
doi = "10.1016/j.physletb.2015.12.039"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1105
AB  - A search is reported for a light pseudoscalar Higgs boson decaying to a pair of tau leptons, produced in association with a b (b) over bar pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 fb(-1). Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the product of cross section and branching fraction to tau pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with SM-like Higgs boson negative couplings to down-type fermions, produced in association with bb pairs, in Type II, two-Higgs-doublet models. (C) 2016 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommonnorg/licensesiby/4.01).
T2  - Physics Letters B
T1  - Search for a low-mass pseudoscalar Higgs boson produced in association with a b(b)over-bar pair in pp collisions at root s=8 TeV
VL  - 758
SP  - 296
EP  - 320
DO  - 10.1016/j.physletb.2016.05.003
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1105",
abstract = "A search is reported for a light pseudoscalar Higgs boson decaying to a pair of tau leptons, produced in association with a b (b) over bar pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 fb(-1). Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the product of cross section and branching fraction to tau pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with SM-like Higgs boson negative couplings to down-type fermions, produced in association with bb pairs, in Type II, two-Higgs-doublet models. (C) 2016 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommonnorg/licensesiby/4.01).",
journal = "Physics Letters B",
title = "Search for a low-mass pseudoscalar Higgs boson produced in association with a b(b)over-bar pair in pp collisions at root s=8 TeV",
volume = "758",
pages = "296-320",
doi = "10.1016/j.physletb.2016.05.003"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1047
AB  - A search is performed for the production of a massive W boson decaying to a top and a bottom quark. The data analysed correspond to an integrated luminosity of 19.71 fb(-1) collected with the CMS detector at the LHC in proton-proton collisions at root s = 8 TeV. The hadronic decay products of the top quark with high Lorentz boost from the W boson decay are detected as a single top flavoured jet. The use of jet substructure algorithms allows the top quark jet to be distinguished from standard model QCD background. Limits on the production cross section of a right-handed W boson are obtained, together with constraints on the left-handed and right-handed couplings of the W boson to quarks. The production of a right-handed W boson with a mass below 2.02 TeV decaying to a hadronic final state is excluded at 95% confidence level. This mass limit increases to 2.15 TeV when both hadronic and leptonic decays are considered, and is the most stringent lower mass limit to date in the tb decay mode.
T2  - Journal of High Energy Physics
T1  - Search for W - GT tb in proton-proton collisions at root s=8 TeV
IS  - 2
DO  - 10.1007/JHEP02(2016)122
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1047",
abstract = "A search is performed for the production of a massive W boson decaying to a top and a bottom quark. The data analysed correspond to an integrated luminosity of 19.71 fb(-1) collected with the CMS detector at the LHC in proton-proton collisions at root s = 8 TeV. The hadronic decay products of the top quark with high Lorentz boost from the W boson decay are detected as a single top flavoured jet. The use of jet substructure algorithms allows the top quark jet to be distinguished from standard model QCD background. Limits on the production cross section of a right-handed W boson are obtained, together with constraints on the left-handed and right-handed couplings of the W boson to quarks. The production of a right-handed W boson with a mass below 2.02 TeV decaying to a hadronic final state is excluded at 95% confidence level. This mass limit increases to 2.15 TeV when both hadronic and leptonic decays are considered, and is the most stringent lower mass limit to date in the tb decay mode.",
journal = "Journal of High Energy Physics",
title = "Search for W - GT tb in proton-proton collisions at root s=8 TeV",
number = "2",
doi = "10.1007/JHEP02(2016)122"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1195
AB  - The inelastic hadronic cross section in proton-lead collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV is measured with the CMS detector at the LHC. The data sample, corresponding to an integrated luminosity of L = 12.6 +/- 0.4 nb(-1), has been collected with an unbiased trigger for inclusive particle production. The cross section is obtained from the measured number of proton-lead collisions with hadronic activity produced in the pseudorapidity ranges 3 LT eta LT 5 and/or -5 LT eta LT -3, corrected for photon-induced contributions, experimental acceptance, and other instrumental effects. The inelastic cross section is measured to be sigma(inel)(pPb) = 2061 +/- 3(stat) +/- 34(syst) +/- 72(lumi) mb. Various Monte Carlo generators, commonly used in heavy ion and cosmic ray physics, are found to reproduce the data within uncertainties. The value of sigma(inel)(pPb) is compatible with that expected from the proton-proton cross section at 5.02 TeV scaled up within a simple Glauber approach to account for multiple scatterings in the lead nucleus, indicating that further net nuclear corrections are small. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org//licenses/by/4.0/).
T2  - Physics Letters B
T1  - Measurement of the inelastic cross section in proton-lead collisions at root s(NN)=5.02 TeV
VL  - 759
SP  - 641
EP  - 662
DO  - 10.1016/j.physletb.2016.06.027
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1195",
abstract = "The inelastic hadronic cross section in proton-lead collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV is measured with the CMS detector at the LHC. The data sample, corresponding to an integrated luminosity of L = 12.6 +/- 0.4 nb(-1), has been collected with an unbiased trigger for inclusive particle production. The cross section is obtained from the measured number of proton-lead collisions with hadronic activity produced in the pseudorapidity ranges 3 LT eta LT 5 and/or -5 LT eta LT -3, corrected for photon-induced contributions, experimental acceptance, and other instrumental effects. The inelastic cross section is measured to be sigma(inel)(pPb) = 2061 +/- 3(stat) +/- 34(syst) +/- 72(lumi) mb. Various Monte Carlo generators, commonly used in heavy ion and cosmic ray physics, are found to reproduce the data within uncertainties. The value of sigma(inel)(pPb) is compatible with that expected from the proton-proton cross section at 5.02 TeV scaled up within a simple Glauber approach to account for multiple scatterings in the lead nucleus, indicating that further net nuclear corrections are small. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org//licenses/by/4.0/).",
journal = "Physics Letters B",
title = "Measurement of the inelastic cross section in proton-lead collisions at root s(NN)=5.02 TeV",
volume = "759",
pages = "641-662",
doi = "10.1016/j.physletb.2016.06.027"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/988
AB  - A search for compositeness of electrons and muons is presented using a data sample of proton-proton collisions at a center-of-mass energy of root s = 8TeV collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 fb(-1). Excited leptons (l*) produced via contact interactions in conjunction with a standard model lepton are considered, and a search is made for their gauge decay modes. The decays considered are l* - GT l gamma and l* - GT lZ , which give final states of two leptons and a photon or, depending on the Z-boson decay mode, four leptons or two leptons and two jets. The number of events observed in data is consistent with the standard model prediction. Exclusion limits are set on the excited lepton mass, and the compositeness scale Lambda. For the case M-l* = Lambda the existence of excited electrons (muons) is excluded up to masses of 2.45 (2.47) TeV at 95% confidence level. Neutral current decays of excited leptons are considered for the first time, and limits are extended to include the possibility that the weight factors f and f, which determine the couplings between standard model leptons and excited leptons via gauge mediated interactions, have opposite sign.
T2  - Journal of High Energy Physics
T1  - Search for excited leptons in proton-proton collisions at root s=8 TeV
IS  - 3
DO  - 10.1007/JHEP03(2016)125
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/988",
abstract = "A search for compositeness of electrons and muons is presented using a data sample of proton-proton collisions at a center-of-mass energy of root s = 8TeV collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 fb(-1). Excited leptons (l*) produced via contact interactions in conjunction with a standard model lepton are considered, and a search is made for their gauge decay modes. The decays considered are l* - GT l gamma and l* - GT lZ , which give final states of two leptons and a photon or, depending on the Z-boson decay mode, four leptons or two leptons and two jets. The number of events observed in data is consistent with the standard model prediction. Exclusion limits are set on the excited lepton mass, and the compositeness scale Lambda. For the case M-l* = Lambda the existence of excited electrons (muons) is excluded up to masses of 2.45 (2.47) TeV at 95% confidence level. Neutral current decays of excited leptons are considered for the first time, and limits are extended to include the possibility that the weight factors f and f, which determine the couplings between standard model leptons and excited leptons via gauge mediated interactions, have opposite sign.",
journal = "Journal of High Energy Physics",
title = "Search for excited leptons in proton-proton collisions at root s=8 TeV",
number = "3",
doi = "10.1007/JHEP03(2016)125"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/916
AB  - A search is presented for a singly produced excited bottom quark (b*) decaying to a top quark and a W boson in the all-hadronic, lepton+jets, and dilepton final states in proton-proton collisions at root s = 8 TeV recorded by the CMS experiment at the CERN LHC. Data corresponding to an integrated luminosity of 19.7 fb(-1) are used. No significant excess of events is observed with respect to standard model expectations. We set limits at 95% confidence on the product of the b* quark production cross section and its branching fraction to tW. The cross section limits are interpreted for scenarios including left-handed, right-handed, and vector-like couplings of the b* quark and are presented in the two-dimensional coupling plane based on the production and decay coupling constants. The masses of the left-handed, right-handed, and vector-like b* quark states are excluded at 95% confidence below 1390, 1430, and 1530 GeV, respectively, for benchmark couplings. This analysis gives the most stringent limits on the mass of the b* quark to date.
T2  - Journal of High Energy Physics
T1  - Search for the production of an excited bottom quark decaying to tW in proton-proton collisions at root s=8 TeV
IS  - 1
DO  - 10.1007/jhep01(2016)166
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/916",
abstract = "A search is presented for a singly produced excited bottom quark (b*) decaying to a top quark and a W boson in the all-hadronic, lepton+jets, and dilepton final states in proton-proton collisions at root s = 8 TeV recorded by the CMS experiment at the CERN LHC. Data corresponding to an integrated luminosity of 19.7 fb(-1) are used. No significant excess of events is observed with respect to standard model expectations. We set limits at 95% confidence on the product of the b* quark production cross section and its branching fraction to tW. The cross section limits are interpreted for scenarios including left-handed, right-handed, and vector-like couplings of the b* quark and are presented in the two-dimensional coupling plane based on the production and decay coupling constants. The masses of the left-handed, right-handed, and vector-like b* quark states are excluded at 95% confidence below 1390, 1430, and 1530 GeV, respectively, for benchmark couplings. This analysis gives the most stringent limits on the mass of the b* quark to date.",
journal = "Journal of High Energy Physics",
title = "Search for the production of an excited bottom quark decaying to tW in proton-proton collisions at root s=8 TeV",
number = "1",
doi = "10.1007/jhep01(2016)166"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/995
AB  - Results are presented from a search for new physics in final states containing a photon and missing transverse momentum. The data correspond to an integrated luminosity of 19.6 fb(-1) collected in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC. Nodeviation from the standard model predictions is observed for these final states. New, improved limits are set on dark matter production and on parameters of models with large extra dimensions. In particular, the first limits from the LHC on branon production are found and significantly extend previous limits from LEP and the Tevatron. An upper limit of 14.0 fb on the cross section is set at the 95% confidence level for events with a monophoton final state with photon transverse momentum greater than 145 GeV and missing transverse momentum greater than 140 GeV. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
T2  - Physics Letters B
T1  - Search for new phenomena in monophoton final states in proton-proton collisions at root s=8 TeV
VL  - 755
SP  - 102
EP  - 124
DO  - 10.1016/j.physletb.2016.01.057
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/995",
abstract = "Results are presented from a search for new physics in final states containing a photon and missing transverse momentum. The data correspond to an integrated luminosity of 19.6 fb(-1) collected in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC. Nodeviation from the standard model predictions is observed for these final states. New, improved limits are set on dark matter production and on parameters of models with large extra dimensions. In particular, the first limits from the LHC on branon production are found and significantly extend previous limits from LEP and the Tevatron. An upper limit of 14.0 fb on the cross section is set at the 95% confidence level for events with a monophoton final state with photon transverse momentum greater than 145 GeV and missing transverse momentum greater than 140 GeV. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "Search for new phenomena in monophoton final states in proton-proton collisions at root s=8 TeV",
volume = "755",
pages = "102-124",
doi = "10.1016/j.physletb.2016.01.057"
}

TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ekmedzic, M.
AU  - Milošević, Jovan
AU  - Rekovic, V.
AU  - Đorđević, Miloš
AU  - Milenović, Predrag
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/931
AB  - We present a measurement of b jet transverse momentum (p(T)) spectra in proton-lead (pPb) collisions using a dataset corresponding to about 35nb(-1) collected with the CMS detector at the LHC. Jets from b quark fragmentation are found by exploiting the long lifetime of hadrons containing a b quark through tagging methods using distributions of the secondary vertex mass and displacement. Extracted cross sections for b jets are scaled by the effective number of nucleon-nucleon collisions and are compared to a reference obtained from PYTHIA simulations of pp collisions. The PYTHIA-based estimate of the nuclear modification factor is found to be 1.22 +/- 0.15 (stat + syst pPb) +/- 0.27 (syst PYTHIA) averaged over all jets with p(T) between 55 and 400 GeV/c and with |eta(lab)| LT 2. We also compare this result to predictions from models using perturbative calculations in quantum chromodynamics. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
T2  - Physics Letters B
T1  - Transverse momentum spectra of inclusive b jets in pPb collisions atv root s(NN)=5.02 TeV
VL  - 754
SP  - 59
EP  - 80
DO  - 10.1016/j.physletb.2016.01.010
ER  - 

@article{
author = "Khachatryan, V. and Adžić, Petar and Ekmedzic, M. and Milošević, Jovan and Rekovic, V. and Đorđević, Miloš and Milenović, Predrag",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/931",
abstract = "We present a measurement of b jet transverse momentum (p(T)) spectra in proton-lead (pPb) collisions using a dataset corresponding to about 35nb(-1) collected with the CMS detector at the LHC. Jets from b quark fragmentation are found by exploiting the long lifetime of hadrons containing a b quark through tagging methods using distributions of the secondary vertex mass and displacement. Extracted cross sections for b jets are scaled by the effective number of nucleon-nucleon collisions and are compared to a reference obtained from PYTHIA simulations of pp collisions. The PYTHIA-based estimate of the nuclear modification factor is found to be 1.22 +/- 0.15 (stat + syst pPb) +/- 0.27 (syst PYTHIA) averaged over all jets with p(T) between 55 and 400 GeV/c and with |eta(lab)| LT 2. We also compare this result to predictions from models using perturbative calculations in quantum chromodynamics. (C) 2016 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.",
journal = "Physics Letters B",
title = "Transverse momentum spectra of inclusive b jets in pPb collisions atv root s(NN)=5.02 TeV",
volume = "754",
pages = "59-80",
doi = "10.1016/j.physletb.2016.01.010"
}