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Search for new phenomena with the MT2 variable in the all-hadronic final state produced in proton-proton collisions at ?s=13TeV
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Johnson, A.; Adam, W.; Ambrogi, F.; Asilar, E.; The CMS Collaboration
A search for new phenomena is performed using events with jets and significant transverse momentum imbalance, as inferred through the M-T2 variable. The results are based on a sample of proton-proton collisions collected in 2016 at a center-of-mass energy of 13 TeV with the CMS detector and corresponding to an integrated luminosity of 35.9 fb(-1). No excess event yield is observed above the predicted standard model background, and the results are interpreted as exclusion limits at 95% confidence level on the masses of predicted particles in a variety of simplified models of R-parity conserving supersymmetry. Depending on the details of the model, 95% confidence level lower limits on the gluino (light-flavor squark) masses are placed up to 2025 (1550) GeV. Mass limits as high as 1070 (1175) GeV are set on the masses of top (bottom) squarks. Information is provided to enable re-interpretation of these results, including model-independent limits on the number of non-standard model events for a set of simplified, inclusive search regions.
Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of W and Z Bosons Using pp Collisions at ?s=13 TeV
(Amer Physical Soc, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at root s = 13 TeV is presented. The data sample corresponds to an integrated luminosity of 15.2 fb(-1) collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.
Observation of Top Quark Production in Proton-Nucleus Collisions
(Amer Physical Soc, 2017) Sirunyan, A. M.; Turnasyan, A.; Adam, W.; Arribrogi, F.; Asilar, E.; Bergauer, T.; The CMS Collaboration
The first observation of top quark production in proton-nucleus collisions is reported using proton-lead data collected by the CMS experiment at the CERN LHC at a nucleon-nucleon center-of-mass energy of root(S)(NN) = 8.16 TeV. The measurement is performed using events with exactly one isolated electron or muon candidate and at least four jets. The data sample corresponds to an integrated luminosity of 174 nb(-1). The significance of the tt signal against the background-only hypothesis is above 5 standard deviations. The measured cross section is sigma(tt) = 45 +/- 8 nb, consistent with predictions from perturbative quantum chromodynamics.
Measurement of the B± Meson Nuclear Modification Factor in Pb-Pb Collisions at ?sNN=5.02 TeV
(Amer Physical Soc, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
The differential production cross sections of B-+/- mesons are measured via the exclusive decay channels B-+/- -> J/psi K-+/- -> mu(+)mu K--(+/-) as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy root s(NN) = 5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb - Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0 pb(-1) (351 mu b(-1)). The measurement is performed in the B-+/- meson transverse momentum range of 7 to 50 GeV/c, in the rapidity interval vertical bar y vertical bar < 2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.
Emotional regulation strategies and negotiation
(Sage Publications Inc, 2004) Yurtsever, G
This study examined the relationship between profit achievement and emotional regulation strategies, using Kelley's Negotiation Game to measure profit achievement. The game involves bargaining for the prices of three products. Emotional Regulation Strategies were measured by The Emotional Regulation Questionnaire. Scores were obtained from 104 lower level managers of a bank in Turkey. Their average age was 32.0 yr. (SD=3.7), (39 women and 65 men). A correlation of .65 (p<.01) was obtained between scores on profit achievement with scores on Cognitive Reappraisal strategy and -.50 (p<.01) with scores on Suppression strategy.
Measurement of prompt and nonprompt J/? production in pp and pPb collisions at ?sNN=5.02 TeV
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
This paper reports the measurement of J/psi meson production in proton proton (pp) and proton lead (pPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV by the CMS experiment at the LW. The data samples used in the analysis correspond to integrated luminosities of 28 ph(-1) and 35 nb(-1) for pp and pPb collisions, respectively. Prompt and nonprompt J/psi mesons, the latter produced in the decay of B hadrons, are measured in their dilution decay channels, Differential cross sections are measured in the transverse momentum range of 2 < p(T) < 30 GeV/c, and center-of-mass rapidity ranges of vertical bar y(CM)vertical bar < 2.4 (pp) and -2.87 < y(CM) < 1.93 (pPb). The nuclear modification factor, R-pPb, is measured as a function of both p(T) and y(CM). Small modifications to the J/psi cross sections are observed in pPb relative to pp collisions. The ratio of J/psi production cross sections in p-going and Pb-going directions, R-FB, studied as functions of p(T) and y(CM), shows a significant decrease for increasing transverse energy deposited at large pseudorapidities. These results, which cover a wide kinematic range, provide new insight on the role of cold nuclear matter effects on prompt and nonprompt J/psi production.
Do Correlations Between Mindfulness Components and Rumination in Student Athletes Support Mindfulness Training to Reduce Rumination?
(Sage Publications Inc, 2021) Tingaz, Emre Ozan; Cakmak, Soner
In the present study, we examined the relationship between mindfulness and rumination among student-athletes. Ninety-seven young adult student-athletes (38.1% female, 61.9% male; M-age = 22.52, SD = 3.53) completed both the Mindfulness Inventory for Sport and the Ruminative Thought Style Questionnaire. Among these participants, we observed a significant positive correlation between rumination and the awareness sub-dimension of mindfulness. We also observed significant negative correlations between rumination and two scores from the Mindfulness Inventory for Sport: non-judgment and overall mindfulness. Awareness, non-judgment, and mindfulness were all significant predictors of rumination in a linear regression analysis. While these are correlational data that do not permit causal inferences, these findings raise the possibility, in this population, that awareness triggers ruminative thoughts and overall mindfulness might represent a coping tool for rumination. Further research is needed to test this possibility.
Relative Modification of Prompt ?(2S) and J/? Yields from pp to PbPb Collisions at ?SNN=5.02 TeV
(Amer Physical Soc, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
The relative modification of the prompt psi(2S) and J/psi yields from pp to PbPb collisions, at the center-of- mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0 pb(-1) and 464 mu b(-1), respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs,(N-psi(2S)/N J/psi )(PbPb)/(N-psi((2S))/N (J/psi) )(pp),is determined as a function of PbPb collision centrality and charmonium transverse momentum p(T), in two kinematic intervals: broken vertical bar y vertical bar < 1.6 covering 6.5 < pT < 30 GeV/c and 1.6 < broken vertical bar y vertical bar < 2.4 covering 3 < pT < 30 GeV/c. The centrality-integrated double ratios are 0.36 +/- 0.08(stat) +/- 0.05(syst) in the first interval and 0.24 +/- 0.22(stat) +/- 0.09(syst) in the second. The double ratio is lower than unity in all the measured bins, suggesting that the psi(2S) yield is more suppressed than the J/psi yield in the explored phase space.
Suppression of Excited ? States Relative to the Ground State in Pb-Pb Collisions at ?sNN=5.02 TeV
(Amer Physical Soc, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
The relative yields of gamma mesons produced in pp and Pb-Pb collisions at root s(NN) = 5.02 TeV and reconstructed via the dimuon decay channel are measured using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states, gamma(2S) and gamma(3S), to the ground state, gamma(1S), in both Pb-Pb and pp collisions at the same center-of-mass energy. The double ratios, [gamma(nS)/gamma(1S)](Pb-Pb)/[gamma(nS)/gamma(1S)](PP), are measured to be 0.308 +/- 0.055(stat) +/- 0.019(syst) for the gamma(2S) and less than 0.26 at 95% confidence level for the gamma(3S). No significant gamma(3S) signal is found in the Pb-Pb data. The double ratios are studied as a function of collision centrality, as well as gamma transverse momentum and rapidity. No significant dependencies are observed.
Search for dark matter produced in association with heavy-flavor quark pairs in proton-proton collisions at ?s=13 TeV
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
A search is presented for an excess of events with heavy-flavor quark pairs (t (t) over bar and b (b) over bar) and a large imbalance in transverse momentum in data from proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 2.2 fb(-1) collected with the CMS detector at the CERN LHC. No deviations are observed with respect to standard model predictions. The results are used in the first interpretation of dark matter production in t (t) over bar and b (b) over bar final states in a simplified model. This analysis is also the first to perform a statistical combination of searches for dark matter produced with different heavy-flavor final states. The combination provides exclusions that are stronger than those achieved with individual heavy-flavor final states.
Measurement of the triple-differential dijet cross section in proton-proton collisions at ?s=8 TeV and constraints on parton distribution functions
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
A measurement is presented of the triple-differential dijet cross section at a centre-of-mass energy of 8 TeV using 19.7 fb(-1) of data collected with the CMS detector in proton-proton collisions at the LHC. The cross section is measured as a function of the average transverse momentum, half the rapidity separation, and the boost of the two leading jets in the event. The cross section is corrected for detector effects and compared to calculations in perturbative quantum chromodynamics at next-to-leading order accuracy, complemented with electroweak and nonperturbative corrections. New constraints on parton distribution functions are obtained and the inferred value of the strong coupling constant is alpha(S)(M-Z) = 0.1199 +/- 0.0015 (exp)(-0.0020)(+0.0031) (theo), where M-Z is the mass of the Z boson.
Study of Jet Quenching with Z plus jet Correlations in Pb-Pb and pp Collisions at ?sNN=5.02 TeV
(Amer Physical Soc, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
The production of jets in association with Z bosons, reconstructed via the mu(+)mu(-) and e(+)e(-) decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum p(T)(Z) > 60 GeV/c and a recoiling jet with p(T)(jet) > 30 GeV/c. The p(T) imbalance x(jZ) = p(T)(jet)/p(T)(Z), as well as the average number of jet partners per Z, R-jZ, was studied in intervals of p(T)(Z). The R-jZ is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30 GeV/c p(T)(jet) threshold because they lose energy.
Measurement of double-differential cross sections for top quark pair production in pp collisions at ?s=8 TeV and impact on parton distribution functions
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
Normalized double-differential cross sections for top quark pair (t (t) over bar) production are measured in pp collisions at a centre-of-mass energy of 8 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7 fb(-1). The measurement is performed in the dilepton e(+/-)mu(+/-) final state. The tt cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and tt system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured tt cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution.
Searches for pair production of third-generation squarks in ?s=13 TeV pp collisions
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
Searches are presented for direct production of top or bottom squark pairs in proton-proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13 TeV with the CMS detector and correspond to an integrated luminosity of 2.3 fb(-1). No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of top or bottom squark pair production. Models with top and bottom squark masses up to 830 and 890 GeV, respectively, are probed for light neutralinos. For models with top squark masses of 675 GeV, neutralino masses up to 260 GeV are excluded at 95% confidence level.
Measurement of the jet mass in highly boosted t(t)over-bar events from pp collisions at ?s=8TeV
(Springer, 2017) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
The first measurement of the jet mass m(jet) of top quark jets produced in t (t) over bar events from pp collisions at root s = 8 TeV is reported for the jet with the largest transverse momentum p(T) in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7 fb(-1). The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay t -> bW with W -> l nu where l is an electron or muon, are used to select t (t) over bar events with large Lorentz boosts. The products of the fully hadronic decay t -> bW with W -> q (q) over bar ' are reconstructed using a single Cambridge-Aachen jet with distance parameter R = 1.2, and pT > 400 GeV. The t (t) over bar cross section as a function of m(jet) is unfolded at the particle level and is used to test the modelling of highly boosted top quark production. The peak position of the m(jet) distribution is sensitive to the top quark mass m(t), and the data are used to extract a value of m(t) to assess this sensitivity.
Study of dijet events with a large rapidity gap between the two leading jets in pp collisions at ?s=7 TeV
(Springer, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; The CMS Collaboration
Events with no charged particles produced between the two leading jets are studied in proton-proton collisions at root s = 7 TeV. The jets were required to have transverse momentum p(T)(jet) > 40 GeV and pseudorapidity 1.5 < vertical bar eta(jet)vertical bar < 4.7, and to have values of eta(jet) with opposite signs. The data used for this study were collected with the CMSdetector during low-luminosity running at the LHC, and correspond to an integrated luminosity of 8 pb(-1). Events with no charged particles with p(T) > 0.2GeV in the interval -1 < eta < 1 between the jets are observed in excess of calculations that assume no color-singlet exchange. The fraction of events with such a rapidity gap, amounting to 0.5-1% of the selected dijet sample, is measured as a function of the pT of the second-leading jet and of the rapidity separation between the jets. The data are compared to previous measurements at the Tevatron, and to perturbative quantum chromodynamics calculations based on the Balitsky-Fadin-Kuraev-Lipatov evolution equations, including different models of the non-perturbative gap survival probability.
Measurement of prompt and nonprompt charmonium suppression in PbPb collisions at 5.02 TeV
(Springer, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; The CMS Collaboration
The nuclear modification factors of J/psi and psi(2S) mesons are measured in PbPb collisions at a centre-of-mass energy per nucleon pair of root S-NN = 5.02 TeV. The analysis is based on PbPb and pp data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464 mu b(-1) and 28 pb(-1), respectively. The measurements are performed in the dimuon rapidity range of vertical bar y vertical bar < 2.4 as a function of centrality, rapidity, and transverse momentum (p(T)) from p(T) = 3 GeV/c in the most forward region and up to 50 GeV/c. Both prompt and nonprompt (coming from b hadron decays) J/psi mesons are observed to be increasingly suppressed with centrality, with a magnitude similar to the one observed at root S-NN = 2.76 TeV for the two J/psi meson components. No dependence on rapidity is observed for either prompt or nonprompt J/psi mesons. An indication of a lower prompt J/psi meson suppression at p(T) > 25 GeV/c is seen with respect to that observed at intermediate p(T). The prompt psi(2S) meson yield is found to be more suppressed than that of the prompt J/psi mesons in the entire p(T) range.
Measurement of Prompt D0 Meson Azimuthal Anisotropy in Pb-Pb Collisions at ?SNN=5.02 TeV
(Amer Physical Soc, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; The CMS Collaboration
The prompt D-0 meson azimuthal anisotropy coefficients, v(2) and ?v(3), are measured at midrapidity ( |y| < 1.0) in Pb-Pb collisions at a center-of-mass energy root s(NN) = 5.02 TeV per nucleon pair with data collected by the CMS experiment. The measurement is performed in the transverse momentum (p(T)) range of 1 to 40 GeV/c, for central and midcentral collisions. The v(2) coefficient is found to be positive throughout the p(T) range studied. The first measurement of the prompt D-0 meson v(3) coefficient is performed, and values up to 0.07 are observed for p(T) around 4 GeV/c. Compared to measurements of charged particles, a similar p(T) dependence, but smaller magnitude for p(T) < 6 GeV/r, is found for prompt D-0 meson v(2) and v(3) coefficients. The results are consistent with the presence of collective motion of charm quarks at low p(r) and a path length dependence of charm quark energy loss at high p(r), thereby providing new constraints on the theoretical description of the interactions between charm quarks and the quark-gluon plasma.
Measurement of the Splitting Function in &ITpp &ITand Pb-Pb Collisions at ?&ITsNN&IT=5.02 TeV
(Amer Physical Soc, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; The CMS Collaboration
Data from heavy ion collisions suggest that the evolution of a parton shower is modified by interactions with the color charges in the dense partonic medium created in these collisions, but it is not known where in the shower evolution the modifications occur. The momentum ratio of the two leading partons, resolved as subjets, provides information about the parton shower evolution. This substructure observable, known as the splitting function, reflects the process of a parton splitting into two other partons and has been measured for jets with transverse momentum between 140 and 500 GeV, in pp and PbPb collisions at a center-of-mass energy of 5.02 TeV per nucleon pair. In central PbPb collisions, the splitting function indicates a more unbalanced momentum ratio, compared to peripheral PbPb and pp collisions.. The measurements are compared to various predictions from event generators and analytical calculations.
Measurements of the pp ? ZZ production cross section and the Z ? 4l branching fraction, and constraints on anomalous triple gauge couplings at ?s=13TeV
(Springer, 2018) Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; The CMS Collaboration
Four-lepton production in proton-proton collisions, pp -> (Z/gamma*)(Z/gamma*) -> 4l, where l = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The ZZ production cross section, sigma(pp -> ZZ) = 17.2 +/- 0.5 (stat) +/- 0.7 (syst) +/- 0.4 (theo) +/- 0.4 (lumi) pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60 < m(l+l-) < 120 GeV, is consistent with standard model predictions. Differential cross sections are measured and are well described by the theoretical predictions. The Z boson branching fraction to four leptons is measured to be B(Z -> 4l) = 4.83(-0.22)(+0.23) (stat)(-0.29)(+0.32) (syst) +/- 0.08 (theo) +/- 0.12(lumi) x 10(-6) for events with a four-lepton invariant mass in the range 80 < m(4l) < 100 GeV and a dilepton mass m(ll) > 4GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ. couplings at 95% confidence level: -0.0012 < f(4)(Z) < 0.0010, -0.0010 < f(5)(Z) < 0.0013, -0.0012 < f(4)(gamma) < 0.0013, -0.0012 < f(5)(gamma) < 0.0013.

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