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Multi-omic analysis of the tumor microenvironment shows clinical correlations in Ph1 study of atezolizumab +/- SoC in MM. Front Immunol 2023; 14:1085893. [PMID: 37559718 PMCID: PMC10408441 DOI: 10.3389/fimmu.2023.1085893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 05/23/2023] [Indexed: 08/11/2023] Open
Abstract
Multiple myeloma (MM) remains incurable, and treatment of relapsed/refractory (R/R) disease is challenging. There is an unmet need for more targeted therapies in this setting; deep cellular and molecular phenotyping of the tumor and microenvironment in MM could help guide such therapies. This phase 1b study (NCT02431208) evaluated the safety and efficacy of the anti-programmed death-ligand 1 monoclonal antibody atezolizumab (Atezo) alone or in combination with the standard of care (SoC) treatments lenalidomide (Len) or pomalidomide (Pom) and/or daratumumab (Dara) in patients with R/R MM. Study endpoints included incidence of adverse events (AEs) and overall response rate (ORR). A novel unsupervised integrative multi-omic analysis was performed using RNA sequencing, mass cytometry immunophenotyping, and proteomic profiling of baseline and on-treatment bone marrow samples from patients receiving Atezo monotherapy or Atezo+Dara. A similarity network fusion (SNF) algorithm was applied to preprocessed data. Eighty-five patients were enrolled. Treatment-emergent deaths occurred in 2 patients; both deaths were considered unrelated to study treatment. ORRs ranged from 11.1% (Atezo+Len cohorts, n=18) to 83.3% (Atezo+Dara+Pom cohort, n=6). High-dimensional multi-omic profiling of the tumor microenvironment and integrative SNF analysis revealed novel correlations between cellular and molecular features of the tumor and immune microenvironment, patient selection criteria, and clinical outcome. Atezo monotherapy and SoC combinations were safe in this patient population and demonstrated some evidence of clinical efficacy. Integrative analysis of high dimensional genomics and immune data identified novel clinical correlations that may inform patient selection criteria and outcome assessment in future immunotherapy studies for myeloma.
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Combination of Atezolizumab and Obinutuzumab in Patients with Relapsed/Refractory Follicular Lymphoma and Diffuse Large B-Cell Lymphoma: Results from a Phase 1b Study. CLINICAL LYMPHOMA, MYELOMA & LEUKEMIA 2022; 22:e443-e451. [PMID: 35031227 DOI: 10.1016/j.clml.2021.12.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/02/2021] [Accepted: 12/18/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND This was an open-label, phase 1b study assessing the safety, tolerability, preliminary efficacy and pharmacokinetics of the combination of atezolizumab and obinutuzumab in patients with relapsed/refractory follicular lymphoma (FL) or diffuse large B-cell lymphoma (DLBCL). There is a mechanistic rationale suggesting that this combination may enhance recruitment of both innate and adaptive immunity and be effective against CD20+ B-cell malignancies. MATERIALS AND METHODS The study consisted of a safety evaluation stage and an expansion stage. Patients received obinutuzumab 1000 mg intravenously (IV) in cycle (C) 1, obinutuzumab plus atezolizumab 1200 mg IV for C2-8, and atezolizumab only from C9. Primary endpoints were to identify a recommended phase 2 dose (RP2D) for atezolizumab, and safety and tolerability in the safety and expansion stages. RESULTS A total of 49 patients were enrolled (FL, n = 26; DLBCL, n = 23), with a median of 2 prior lines of treatment. The RP2D for atezolizumab was 1200 mg IV every 3 weeks. Adverse events reported in ≥ 20% of patients were fatigue (15 patients [31%]), nausea (13 patients [27%]), cough, and diarrhea (10 patients [20%] each). Objective response rate was 54% in the FL cohort (complete response [CR] rate: 23%) and 17% in the DLBCL cohort (CR: 4%). Median progression-free survival was 9 months for FL and 3 months for DLBCL. Median overall survival was not estimable for FL and 9 months for DLBCL. CONCLUSION The combination of obinutuzumab and atezolizumab was determined to be safe and tolerable, with no new toxicities observed.
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Combination of Atezolizumab and Tazemetostat in Patients With Relapsed/Refractory Diffuse Large B-Cell Lymphoma: Results From a Phase Ib Study. CLINICAL LYMPHOMA, MYELOMA & LEUKEMIA 2022; 22:504-512. [PMID: 35151584 DOI: 10.1016/j.clml.2021.12.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/03/2021] [Accepted: 12/18/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND The combination of atezolizumab, a monoclonal antibody that targets programmed death-ligand 1 (PD-L1) and inhibits the interaction between PD-L1 and its receptors, and tazemetostat, an EZH2 inhibitor, may lead to selective epigenetic reprogramming, alter the tumor microenvironment, and provide additive or synergistic response to patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS This was an open-label, phase Ib study assessing the safety, tolerability, and preliminary efficacy of atezolizumab plustazemetostat in patients with R/R DLBCL. Atezolizumab (1200 mg) was administered via intravenous (IV) infusion on day 1 of each cycle and tazemetostat (800 mg) was given orally twice daily (BID) on days 1 to 21. Primary endpoints were safety and tolerability, and to identify a recommended phase II dose (RP2D) for atezolizumab. Secondary efficacy endpoints included response rate and duration of response. RESULTS A total of 43 patients were enrolled, receiving a median of 3 prior lines of treatment (range: 1-9). The RP2D for atezolizumab was 1200 mg IV infusion every 3 weeks in combination with tazemetostat 800 mg BID. At the RP2D, adverse events reported in ≥20% patients were anemia(11 patients [26%]), fatigue (10 patients [23%]), and nausea (10 patients [23%]). Overall response rate was 16% (complete response rate: 7%). Median progression-free survival was 2 months (range: 0-24) and median overall survival was 13 months (range: 1-29). CONCLUSIONS The combination of atezolizumab and tazemetostat was determined to be safe and tolerable. However, anti-tumor activity of the combination was modest.
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Patient practices regarding topical drugs and a 'nudge' to prevent topical steroid abuse. Clin Exp Dermatol 2020; 46:575-577. [PMID: 33131125 DOI: 10.1111/ced.14497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/06/2020] [Accepted: 10/27/2020] [Indexed: 11/28/2022]
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Venetoclax Increases Intratumoral Effector T Cells and Antitumor Efficacy in Combination with Immune Checkpoint Blockade. Cancer Discov 2020; 11:68-79. [PMID: 32887697 DOI: 10.1158/2159-8290.cd-19-0759] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/11/2020] [Accepted: 09/01/2020] [Indexed: 11/16/2022]
Abstract
The antiapoptotic protein BCL2 plays critical roles in regulating lymphocyte development and immune responses, and has also been implicated in tumorigenesis and tumor survival. However, it is unknown whether BCL2 is critical for antitumor immune responses. We evaluated whether venetoclax, a selective small-molecule inhibitor of BCL2, would influence the antitumor activity of immune checkpoint inhibitors (ICI). We demonstrate in mouse syngeneic tumor models that venetoclax can augment the antitumor efficacy of ICIs accompanied by the increase of PD-1+ T effector memory cells. Venetoclax did not impair human T-cell function in response to antigen stimuli in vitro and did not antagonize T-cell activation induced by anti-PD-1. Furthermore, we demonstrate that the antiapoptotic family member BCL-XL provides a survival advantage in effector T cells following inhibition of BCL2. Taken together, these data provide evidence that venetoclax should be further explored in combination with ICIs for cancer therapy. SIGNIFICANCE: The antiapoptotic oncoprotein BCL2 plays critical roles in tumorigenesis, tumor survival, lymphocyte development, and immune system regulation. Here we demonstrate that venetoclax, the first FDA/European Medicines Agency-approved BCL2 inhibitor, unexpectedly can be combined preclinically with immune checkpoint inhibitors to enhance anticancer immunotherapy, warranting clinical evaluation of these combinations.This article is highlighted in the In This Issue feature, p. 1.
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Differential effects of PD-L1 versus PD-1 blockade on myeloid inflammation in human cancer. JCI Insight 2020; 5:129353. [PMID: 32427579 PMCID: PMC7406262 DOI: 10.1172/jci.insight.129353] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 05/13/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUNDPD-1 and PD-L1 have been studied interchangeably in the clinic as checkpoints to reinvigorate T cells in diverse tumor types. Data for biologic effects of checkpoint blockade in human premalignancy are limited.METHODSWe analyzed the immunologic effects of PD-L1 blockade in a clinical trial of atezolizumab in patients with asymptomatic multiple myeloma (AMM), a precursor to clinical malignancy. Genomic signatures of PD-L1 blockade in purified monocytes and T cells in vivo were also compared with those following PD-1 blockade in lung cancer patients. Effects of PD-L1 blockade on monocyte-derived DCs were analyzed to better understand its effects on myeloid antigen-presenting cells.RESULTSIn contrast to anti-PD-1 therapy, anti-PD-L1 therapy led to a distinct inflammatory signature in CD14+ monocytes and increase in myeloid-derived cytokines (e.g., IL-18) in vivo. Treatment of AMM patients with atezolizumab led to rapid activation and expansion of circulating myeloid cells, which persisted in the BM. Blockade of PD-L1 on purified monocyte-derived DCs led to rapid inflammasome activation and synergized with CD40L-driven DC maturation, leading to greater antigen-specific T cell expansion.CONCLUSIONThese data show that PD-L1 blockade leads to distinct systemic immunologic effects compared with PD-1 blockade in vivo in humans, particularly manifest as rapid myeloid activation. These findings also suggest an additional role for PD-L1 as a checkpoint for regulating inflammatory phenotype of myeloid cells and antigen presentation in DCs, which may be harnessed to improve PD-L1-based combination therapies.TRIAL REGISTRATIONNCT02784483.FUNDINGThis work is supported, in part, by funds from NIH/NCI (NCI CA197603, CA238471, and CA208328).
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SAFETY AND CLINICAL ACTIVITY OF ATEZOLIZUMAB IN COMBINATION WITH TAZEMETOSTAT IN RELAPSED OR REFRACTORY DIFFUSE LARGE B-CELL LYMPHOMA: PRIMARY ANALYSIS OF A PHASE 1B STUDY. Hematol Oncol 2019. [DOI: 10.1002/hon.203_2631] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Reversibility of Defective Hematopoiesis Caused by Telomere Shortening in Telomerase Knockout Mice. PLoS One 2015; 10:e0131722. [PMID: 26133370 PMCID: PMC4489842 DOI: 10.1371/journal.pone.0131722] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 06/04/2015] [Indexed: 01/08/2023] Open
Abstract
Telomere shortening is common in bone marrow failure syndromes such as dyskeratosis congenita (DC), aplastic anemia (AA) and myelodysplastic syndromes (MDS). However, improved knowledge of the lineage-specific consequences of telomere erosion and restoration of telomere length in hematopoietic progenitors is required to advance therapeutic approaches. We have employed a reversible murine model of telomerase deficiency to compare the dependence of erythroid and myeloid lineage differentiation on telomerase activity. Fifth generation Tert-/- (G5 Tert-/-) mice with shortened telomeres have significant anemia, decreased erythroblasts and reduced hematopoietic stem cell (HSC) populations associated with neutrophilia and increased myelopoiesis. Intracellular multiparameter analysis by mass cytometry showed significantly reduced cell proliferation and increased sensitivity to activation of DNA damage checkpoints in erythroid progenitors and in erythroid-biased CD150hi HSC, but not in myeloid progenitors. Strikingly, Cre-inducible reactivation of telomerase activity restored hematopoietic stem and progenitor cell (HSPC) proliferation, normalized the DNA damage response, and improved red cell production and hemoglobin levels. These data establish a direct link between the loss of TERT activity, telomere shortening and defective erythropoiesis and suggest that novel strategies to restore telomerase function may have an important role in the treatment of the resulting anemia.
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Regulation of Ribosomal Gene Expression in Cancer. J Cell Physiol 2015; 230:1181-8. [DOI: 10.1002/jcp.24854] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 10/16/2014] [Indexed: 12/20/2022]
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Measurement of differential cross sections for the production of a pair of isolated photons in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:3129. [PMID: 25814874 PMCID: PMC4371070 DOI: 10.1140/epjc/s10052-014-3129-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 10/14/2014] [Indexed: 06/04/2023]
Abstract
A measurement of differential cross sections for the production of a pair of isolated photons in proton-proton collisions at [Formula: see text] is presented. The data sample corresponds to an integrated luminosity of 5.0[Formula: see text] collected with the CMS detector. A data-driven isolation template method is used to extract the prompt diphoton yield. The measured cross section for two isolated photons, with transverse energy above 40 and 25[Formula: see text] respectively, in the pseudorapidity range [Formula: see text], [Formula: see text] and with an angular separation [Formula: see text], is [Formula: see text][Formula: see text]. Differential cross sections are measured as a function of the diphoton invariant mass, the diphoton transverse momentum, the azimuthal angle difference between the two photons, and the cosine of the polar angle in the Collins-Soper reference frame of the diphoton system. The results are compared to theoretical predictions at leading, next-to-leading, and next-to-next-to-leading order in quantum chromodynamics.
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Fda Cdx Category Medication Use During Pregnancy in the United States. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A519. [PMID: 27201617 DOI: 10.1016/j.jval.2014.08.1618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Evidence of b-jet quenching in PbPb collisions at √(s(NN))=2.76 TeV. PHYSICAL REVIEW LETTERS 2014; 113:132301. [PMID: 25302881 DOI: 10.1103/physrevlett.113.132301] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Indexed: 06/04/2023]
Abstract
The production of jets associated to bottom quarks is measured for the first time in PbPb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair. Jet spectra are reported in the transverse momentum (p(T)) range of 80-250 GeV/c, and within pseudorapidity |η|<2. The nuclear modification factor (R(AA)) calculated from these spectra shows a strong suppression in the b-jet yield in PbPb collisions relative to the yield observed in pp collisions at the same energy. The suppression persists to the largest values of p(T) studied, and is centrality dependent. The R(AA) is about 0.4 in the most central events, similar to previous observations for inclusive jets. This implies that jet quenching does not have a strong dependence on parton mass and flavor in the jet p(T) range studied.
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Measurement of jet multiplicity distributions in [Formula: see text] production in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:3014. [PMID: 25814909 PMCID: PMC4371091 DOI: 10.1140/epjc/s10052-014-3014-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 07/30/2014] [Indexed: 06/02/2023]
Abstract
The normalised differential top quark-antiquark production cross section is measured as a function of the jet multiplicity in proton-proton collisions at a centre-of-mass energy of 7[Formula: see text] at the LHC with the CMS detector. The measurement is performed in both the dilepton and lepton+jets decay channels using data corresponding to an integrated luminosity of 5.0[Formula: see text]. Using a procedure to associate jets to decay products of the top quarks, the differential cross section of the [Formula: see text] production is determined as a function of the additional jet multiplicity in the lepton+jets channel. Furthermore, the fraction of events with no additional jets is measured in the dilepton channel, as a function of the threshold on the jet transverse momentum. The measurements are compared with predictions from perturbative quantum chromodynamics and no significant deviations are observed.
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Search for invisible decays of Higgs bosons in the vector boson fusion and associated ZH production modes. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:2980. [PMID: 25814906 PMCID: PMC4370888 DOI: 10.1140/epjc/s10052-014-2980-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 07/13/2014] [Indexed: 06/01/2023]
Abstract
A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a [Formula: see text] quark pair. The searches use the 8 [Formula: see text] pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 [Formula: see text]. Certain channels include data from 7 [Formula: see text] collisions corresponding to an integrated luminosity of 4.9 [Formula: see text]. The searches are sensitive to non-standard-model invisible decays of the recently observed Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at [Formula: see text] [Formula: see text] is found to be 0.58 (0.44) at 95 % confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.
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Measurement of WZ and ZZ production in pp collisions at [Formula: see text] in final states with b-tagged jets. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:2973. [PMID: 25814904 PMCID: PMC4370898 DOI: 10.1140/epjc/s10052-014-2973-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 07/09/2014] [Indexed: 06/04/2023]
Abstract
Measurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at [Formula: see text][Formula: see text] in final states where one Z boson decays to b-tagged jets. The other gauge boson, either W or Z, is detected through its leptonic decay (either [Formula: see text], [Formula: see text] or [Formula: see text], [Formula: see text], or [Formula: see text]). The results are based on data corresponding to an integrated luminosity of 18.9 fb[Formula: see text] collected with the CMS detector at the Large Hadron Collider. The measured cross sections, [Formula: see text] and [Formula: see text], are consistent with next-to-leading order quantum chromodynamics calculations.
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Observation of the associated production of a single top quark and a W boson in pp collisions at sqrt[s] = 8 TeV. PHYSICAL REVIEW LETTERS 2014; 112:231802. [PMID: 24972196 DOI: 10.1103/physrevlett.112.231802] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Indexed: 06/03/2023]
Abstract
The first observation of the associated production of a single top quark and a W boson is presented. The analysis is based on a data set corresponding to an integrated luminosity of 12.2 fb(-1) of proton-proton collisions at sqrt[s] = 8 TeV recorded by the CMS experiment at the LHC. Events with two leptons and a jet originating from a b quark are selected. A multivariate analysis based on kinematic and topological properties is used to separate the signal from the dominant tt background. An excess consistent with the signal hypothesis is observed, with a significance which corresponds to 6.1 standard deviations above a background-only hypothesis. The measured production cross section is 23.4 ± 5.4 pb, in agreement with the standard model prediction.
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Probing color coherence effects in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:2901. [PMID: 25814895 PMCID: PMC4370765 DOI: 10.1140/epjc/s10052-014-2901-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 05/14/2014] [Indexed: 05/31/2023]
Abstract
A study of color coherence effects in pp collisions at a center-of-mass energy of 7[Formula: see text] is presented. The data used in the analysis were collected in 2010 with the CMS detector at the LHC and correspond to an integrated luminosity of 36 pb[Formula: see text]. Events are selected that contain at least three jets and where the two jets with the largest transverse momentum exhibit a back-to-back topology. The measured angular correlation between the second- and third-leading jet is shown to be sensitive to color coherence effects, and is compared to the predictions of Monte Carlo models with various implementations of color coherence. None of the models describe the data satisfactorily.
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Study of the production of charged pions, kaons, and protons in pPb collisions at [Formula: see text]5.02[Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:2847. [PMID: 25814892 PMCID: PMC4370925 DOI: 10.1140/epjc/s10052-014-2847-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 04/04/2014] [Indexed: 05/28/2023]
Abstract
Spectra of identified charged hadrons are measured in pPb collisions with the CMS detector at the LHC at [Formula: see text]. Charged pions, kaons, and protons in the transverse-momentum range [Formula: see text]-1.7[Formula: see text] and laboratory rapidity [Formula: see text] are identified via their energy loss in the silicon tracker. The average [Formula: see text] increases with particle mass and the charged multiplicity of the event. The increase of the average [Formula: see text] with charged multiplicity is greater for heavier hadrons. Comparisons to Monte Carlo event generators reveal that Epos Lhc, which incorporates additional hydrodynamic evolution of the created system, is able to reproduce most of the data features, unlike Hijing and Ampt. The [Formula: see text] spectra and integrated yields are also compared to those measured in pp and PbPb collisions at various energies. The average transverse momentum and particle ratio measurements indicate that particle production at LHC energies is strongly correlated with event particle multiplicity.
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TU-F-BRF-04: Registration of 3D Transesophageal Echocardiography and X-Ray Fluoroscopy Using An Inverse Geometry X-Ray System. Med Phys 2014. [DOI: 10.1118/1.4889322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Measurement of inclusive W and Z boson production cross sections in pp collisions at sqrt[s] = 8 TeV. PHYSICAL REVIEW LETTERS 2014; 112:191802. [PMID: 24877930 DOI: 10.1103/physrevlett.112.191802] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Indexed: 06/03/2023]
Abstract
A measurement of total and fiducial inclusive W and Z boson production cross sections in pp collisions at sqrt[s] = 8 TeV is presented. Electron and muon final states are analyzed in a data sample collected with the CMS detector corresponding to an integrated luminosity of 18.2 ± 0.5 pb(-1). The measured total inclusive cross sections times branching fractions are σ(pp → WX)×B(W → ℓν) = 12.21 ± 0.03(stat) ± 0.24(syst) ± 0.32(lum) nb and σ(pp → ZX) × B(Z → ℓ+ℓ-) = 1.15 ± 0.01(stat) ± 0.02(syst) ± 0.03(lum) nb for the dilepton mass in the range of 60-120 GeV. The measured values agree with next-to-next-to-leading-order QCD cross section calculations. Ratios of cross sections are reported with a precision of 2%. This is the first measurement of inclusive W and Z boson production in proton-proton collisions at sqrt[s] = 8 TeV.
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Measurement of theWγandZγinclusive cross sections inppcollisions ats=7 TeVand limits on anomalous triple gauge boson couplings. Int J Clin Exp Med 2014. [DOI: 10.1103/physrevd.89.092005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Measurements of tt spin correlations and top-quark polarization using dilepton final states in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2014; 112:182001. [PMID: 24856688 DOI: 10.1103/physrevlett.112.182001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Indexed: 06/03/2023]
Abstract
Spin correlations and polarization in the top quark-antiquark system are measured using dilepton final states produced in pp collisions at the LHC at sqrt[s]=7 TeV. The data correspond to an integrated luminosity of 5.0 fb(-1) collected with the CMS detector. The measurements are performed using events with two oppositely charged leptons (electrons or muons), a significant imbalance in transverse momentum, and two or more jets, where at least one of the jets is identified as originating from a b quark. The spin correlations and polarization are measured through asymmetries in angular distributions of the two selected leptons, unfolded to the parton level. All measurements are found to be in agreement with predictions of the standard model.
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Search for top-quark partners with charge 5/3 in the same-sign dilepton final state. PHYSICAL REVIEW LETTERS 2014; 112:171801. [PMID: 24836237 DOI: 10.1103/physrevlett.112.171801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Indexed: 06/03/2023]
Abstract
A search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5 fb(-1) and was collected at sqrt[s] = 8 TeV by the CMS experiment. No significant excess is observed in the data above the expected background, and the existence of top-quark partners with masses below 800 GeV is excluded at a 95% confidence level, assuming they decay exclusively to tW. This is the first limit on these particles from the LHC, and it is significantly more restrictive than previous limits.
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Search for flavor-changing neutral currents in top-quark decays t → Zq in pp collisions at sqrt[s] = 8 TeV. PHYSICAL REVIEW LETTERS 2014; 112:171802. [PMID: 24836238 DOI: 10.1103/physrevlett.112.171802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Indexed: 06/03/2023]
Abstract
A search for flavor-changing neutral currents in top-quark decays t → Zq is performed in events produced from the decay chain tt → Zq+Wb, where both vector bosons decay leptonically, producing a final state with three leptons (electrons or muons). A data set collected with the CMS detector at the LHC is used, corresponding to an integrated luminosity of 19.7 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV. No excess is seen in the observed number of events relative to the standard model prediction; thus, no evidence for flavor-changing neutral currents in top-quark decays is found. A combination with a previous search at 7 TeV excludes a t → Zq branching fraction greater than 0.05% at the 95% confidence level.
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29
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Search for top squark and Higgsino production using diphoton Higgs boson decays. PHYSICAL REVIEW LETTERS 2014; 112:161802. [PMID: 24815637 DOI: 10.1103/physrevlett.112.161802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Indexed: 06/03/2023]
Abstract
Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top quark (the top squark) and the Higgs boson (Higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 fb-1 of proton-proton collision data at s=8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the top squark mass below 360 to 410 GeV, depending on the Higgsino mass.
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30
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Measurement of the top-quark mass in all-jets [Formula: see text] events in pp collisions at [Formula: see text] TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2014; 74:2758. [PMID: 25814885 PMCID: PMC4370827 DOI: 10.1140/epjc/s10052-014-2758-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 12/31/2013] [Indexed: 06/04/2023]
Abstract
The mass of the top quark is measured using a sample of [Formula: see text] candidate events with at least six jets in the final state. The sample is selected from data collected with the CMS detector in pp collisions at [Formula: see text] TeV in 2011 and corresponds to an integrated luminosity of 3.54 [Formula: see text]. The mass is reconstructed for each event employing a kinematic fit of the jets to a [Formula: see text] hypothesis. The top-quark mass is measured to be [Formula: see text] GeV. A combination with previously published measurements in other decay modes by CMS yields a mass of [Formula: see text] GeV.
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32
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Jet and underlying event properties as a function of charged-particle multiplicity in proton-proton collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2674. [PMID: 25814851 PMCID: PMC4371079 DOI: 10.1140/epjc/s10052-013-2674-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 11/18/2013] [Indexed: 06/04/2023]
Abstract
Characteristics of multi-particle production in proton-proton collisions at [Formula: see text] are studied as a function of the charged-particle multiplicity, Nch. The produced particles are separated into two classes: those belonging to jets and those belonging to the underlying event. Charged particles are measured with pseudorapidity |η|<2.4 and transverse momentum pT>0.25 GeV/c. Jets are reconstructed from charged-particles only and required to have pT>5 GeV/c. The distributions of jet pT, average pT of charged particles belonging to the underlying event or to jets, jet rates, and jet shapes are presented as functions of Nch and compared to the predictions of the pythia and herwig event generators. Predictions without multi-parton interactions fail completely to describe the Nch-dependence observed in the data. For increasing Nch, pythia systematically predicts higher jet rates and harder pT spectra than seen in the data, whereas herwig shows the opposite trends. At the highest multiplicity, the data-model agreement is worse for most observables, indicating the need for further tuning and/or new model ingredients.
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33
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Search for top squarks in R-parity-violating supersymmetry using three or more leptons and b-tagged jets. PHYSICAL REVIEW LETTERS 2013; 111:221801. [PMID: 24329437 DOI: 10.1103/physrevlett.111.221801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Indexed: 06/03/2023]
Abstract
A search for anomalous production of events with three or more isolated leptons and bottom-quark jets produced in pp collisions at √s=8 TeV is presented. The analysis is based on a data sample corresponding to an integrated luminosity of 19.5 fb(-1) collected by the CMS experiment at the LHC in 2012. No excess above the standard model expectations is observed. The results are interpreted in the context of supersymmetric models with signatures that have low missing transverse energy arising from light top-squark pair production with R-parity-violating decays of the lightest supersymmetric particle. In two models with different R-parity-violating couplings, top squarks are excluded below masses of 1020 GeV and 820 GeV when the lightest supersymmetric particle has a mass of 200 GeV.
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34
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Searches for new physics using the tt¯ invariant mass distribution in pp collisions at √s=8 TeV. PHYSICAL REVIEW LETTERS 2013; 111:211804. [PMID: 24313480 DOI: 10.1103/physrevlett.111.211804] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Indexed: 06/02/2023]
Abstract
Searches for anomalous top quark-antiquark production are presented, based on pp collisions at √s=8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were collected with the CMS detector at the LHC. The observed tt¯ invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements.
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35
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Search for supersymmetry in hadronic final states with missing transverse energy using the variables αT and b-quark multiplicity in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2568. [PMID: 25814868 PMCID: PMC4371056 DOI: 10.1140/epjc/s10052-013-2568-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 08/14/2013] [Indexed: 06/01/2023]
Abstract
An inclusive search for supersymmetric processes that produce final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of 8 TeV. The data sample corresponds to an integrated luminosity of 11.7 fb-1 collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, αT, is used to discriminate between events with genuine and misreconstructed missing transverse energy. The search is based on an examination of the number of reconstructed jets per event, the scalar sum of transverse energies of these jets, and the number of these jets identified as originating from bottom quarks. No significant excess of events over the standard model expectation is found. Exclusion limits are set in the parameter space of simplified models, with a special emphasis on both compressed-spectrum scenarios and direct or gluino-induced production of third-generation squarks. For the case of gluino-mediated squark production, gluino masses up to 950-1125 GeV are excluded depending on the assumed model. For the direct pair-production of squarks, masses up to 450 GeV are excluded for a single light first- or second-generation squark, increasing to 600 GeV for bottom squarks.
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36
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Measurement of the Bs(0)→μ+ μ- branching fraction and search for B(0)→μ+ μ- with the CMS experiment. PHYSICAL REVIEW LETTERS 2013; 111:101804. [PMID: 25166654 DOI: 10.1103/physrevlett.111.101804] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Indexed: 06/03/2023]
Abstract
Results are presented from a search for the rare decays Bs(0)→μ+ μ- and B(0)→μ+ μ- in pp collisions at sqrt[s]=7 and 8 TeV, with data samples corresponding to integrated luminosities of 5 and 20 fb(-1), respectively, collected by the CMS experiment at the LHC. An unbinned maximum-likelihood fit to the dimuon invariant mass distribution gives a branching fraction B(Bs(0)→μ+ μ-)=(3.0(-0.9)(+1.0))×10(-9), where the uncertainty includes both statistical and systematic contributions. An excess of Bs(0)→μ+ μ- events with respect to background is observed with a significance of 4.3 standard deviations. For the decay B(0)→μ+ μ- an upper limit of B(B(0)→μ+ μ-)<1.1×10(-9) at the 95% confidence level is determined. Both results are in agreement with the expectations from the standard model.
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37
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Inclusive search for supersymmetry using razor variables in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2013; 111:081802. [PMID: 24010428 DOI: 10.1103/physrevlett.111.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Indexed: 06/02/2023]
Abstract
An inclusive search is presented for new heavy particle pairs produced in √s=7 TeV proton-proton collisions at the LHC using 4.7±0.1 fb(-1) of integrated luminosity. The selected events are analyzed in the 2D razor space of M(R), an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The third-generation sector is probed using the event heavy-flavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number of events beyond that predicted by the standard model. Exclusion limits are derived in the CMSSM framework as well as for simplified models. Within the CMSSM parameter space considered, gluino masses up to 800 GeV and squark masses up to 1.35 TeV are excluded at 95% confidence level depending on the model parameters. The direct production of pairs of top or bottom squarks is excluded for masses as high as 400 GeV.
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38
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Search for physics beyond the standard model in events with τ leptons, jets, and large transverse momentum imbalance in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2493. [PMID: 25814865 PMCID: PMC4370880 DOI: 10.1140/epjc/s10052-013-2493-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 06/11/2013] [Indexed: 06/04/2023]
Abstract
A search for physics beyond the standard model is performed with events having one or more hadronically decaying τ leptons, highly energetic jets, and large transverse momentum imbalance. The data sample corresponds to an integrated luminosity of 4.98 fb-1 of proton-proton collisions at [Formula: see text] collected with the CMS detector at the LHC in 2011. The number of observed events is consistent with predictions for standard model processes. Lower limits on the mass of the gluino in supersymmetric models are determined.
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39
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Measurement of masses in the [Formula: see text] system by kinematic endpoints in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2494. [PMID: 25814866 PMCID: PMC4371053 DOI: 10.1140/epjc/s10052-013-2494-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 06/18/2013] [Indexed: 06/04/2023]
Abstract
A simultaneous measurement of the top-quark, W-boson, and neutrino masses is reported for [Formula: see text] events selected in the dilepton final state from a data sample corresponding to an integrated luminosity of 5.0 fb-1 collected by the CMS experiment in pp collisions at [Formula: see text]. The analysis is based on endpoint determinations in kinematic distributions. When the neutrino and W-boson masses are constrained to their world-average values, a top-quark mass value of [Formula: see text] is obtained. When such constraints are not used, the three particle masses are obtained in a simultaneous fit. In this unconstrained mode the study serves as a test of mass determination methods that may be used in beyond standard model physics scenarios where several masses in a decay chain may be unknown and undetected particles lead to underconstrained kinematics.
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40
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Search for a standard-model-like Higgs boson with a mass in the range 145 to 1000 GeV at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2469. [PMID: 25814864 PMCID: PMC4370850 DOI: 10.1140/epjc/s10052-013-2469-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Revised: 05/04/2013] [Indexed: 06/04/2023]
Abstract
A search for a standard-model-like Higgs boson in the H→WW and H→ZZ decay channels is reported, for Higgs boson masses in the range 145
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41
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Search for supersymmetry in pp collisions at [Formula: see text] TeV in events with a single lepton, jets, and missing transverse momentum. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2404. [PMID: 25814857 PMCID: PMC4370766 DOI: 10.1140/epjc/s10052-013-2404-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 03/02/2013] [Indexed: 05/30/2023]
Abstract
Results are reported from a search for new physics processes in events containing a single isolated high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The analysis is based on a 4.98 fb-1 sample of proton-proton collisions at a center-of-mass energy of 7 TeV, obtained with the CMS detector at the LHC. Three separate background estimation methods, each relying primarily on control samples in the data, are applied to a range of signal regions, providing complementary approaches for estimating the background yields. The observed yields are consistent with the predicted standard model backgrounds. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model, as well as on cross sections for simplified models, which provide a generic description of the production and decay of new particles in specific, topology based final states. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (doi:10.1140/epjc/s10052-013-2404-z) contains supplementary material, which is available to authorized users.
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42
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Measurement of associated production of vector bosons and top quark-antiquark pairs in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:172002. [PMID: 23679709 DOI: 10.1103/physrevlett.110.172002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Indexed: 06/02/2023]
Abstract
The first measurement of vector-boson production associated with a top quark-antiquark pair in proton-proton collisions at sqrt[s] = 7 TeV is presented. The results are based on a data set corresponding to an integrated luminosity of 5.0 fb(-1), recorded by the CMS detector at the LHC in 2011. The measurement is performed in two independent channels through a trilepton analysis of ttZ events and a same-sign dilepton analysis of ttV (V = W or Z) events. In the trilepton channel a direct measurement of the ttZ cross section σ(ttZ) = 0.28(-0.11)(+0.14) (stat)(-0.03)(+0.06) (syst) pb is obtained. In the dilepton channel a measurement of the ttV cross section yields σ(ttV) = 0.43(-0.15)(+0.17) (stat)(-0.07)(+0.09) (syst) pb. These measurements have a significance, respectively, of 3.3 and 3.0 standard deviations from the background hypotheses and are compatible, within uncertainties, with the corresponding next-to-leading order predictions of 0.137(-0.016)(+0.012) and 0.306(-0.053)(+0.031) pb.
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43
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Search for new physics in final states with a lepton and missing transverse energy inppcollisions at the LHC. Int J Clin Exp Med 2013. [DOI: 10.1103/physrevd.87.072005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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44
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Search for pair-produced dijet resonances in four-jet final states in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:141802. [PMID: 25166980 DOI: 10.1103/physrevlett.110.141802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Indexed: 06/03/2023]
Abstract
A search for the pair production of a heavy, narrow resonance decaying into two jets has been performed using events collected in sqrt[s] = 7 TeV pp collisions with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb(-1). Events are selected with at least four jets and two dijet combinations with similar dijet mass. No resonances are found in the dijet mass spectrum. The upper limit at 95% confidence level on the product of the resonance pair production cross section, the branching fractions into dijets, and the acceptance varies from 0.22 to 0.005 pb, for resonance masses between 250 and 1200 GeV. Pair-produced colorons decaying into qq are excluded for coloron masses between 250 and 740 GeV.
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45
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Search for contact interactions using the inclusive jetpTspectrum inppcollisions ats=7 TeV. Int J Clin Exp Med 2013. [DOI: 10.1103/physrevd.87.052017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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46
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Search for pair production of third-generation leptoquarks and top squarks in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081801. [PMID: 23473129 DOI: 10.1103/physrevlett.110.081801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for the pair production of third-generation scalar and vector leptoquarks, as well as for top squarks in R-parity-violating supersymmetric models. In either scenario, the new, heavy particle decays into a τ lepton and a b quark. The search is based on a data sample of pp collisions at sqrt[s] = 7 TeV, which is collected by the CMS detector at the LHC and corresponds to an integrated luminosity of 4.8 fb(-1). The number of observed events is found to be in agreement with the standard model prediction, and exclusion limits on mass parameters are obtained at the 95% confidence level. Vector leptoquarks with masses below 760 GeV are excluded and, if the branching fraction of the scalar leptoquark decay to a τ lepton and a b quark is assumed to be unity, third-generation scalar leptoquarks with masses below 525 GeV are ruled out. Top squarks with masses below 453 GeV are excluded for a typical benchmark scenario, and limits on the coupling between the top squark, τ lepton, and b quark, λ(333)(') are obtained. These results are the most stringent for these scenarios to date.
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47
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Measurement of the Υ1S, Υ2S, and Υ3S polarizations in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081802. [PMID: 23473130 DOI: 10.1103/physrevlett.110.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Indexed: 06/01/2023]
Abstract
The polarizations of the Υ(1S), Υ(2S), and Υ(3S) mesons are measured in proton-proton collisions at sqrt[s] = 7 TeV, using a data sample of Υ(nS) → μ +μ- decays collected by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb(-1). The dimuon decay angular distributions are analyzed in three different polarization frames. The polarization parameters λ[symbol see text], λ(φ), and λ([symbol see text]φ), as well as the frame-invariant quantity λ, are presented as a function of the Υ(nS) transverse momentum between 10 and 50 GeV, in the rapidity ranges |y|<0.6 and 0.6<|y|<1.2. No evidence of large transverse or longitudinal polarizations is seen in the explored kinematic region.
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48
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Study of the mass and spin-parity of the Higgs boson candidate via its decays to Z boson pairs. PHYSICAL REVIEW LETTERS 2013; 110:081803. [PMID: 23473131 DOI: 10.1103/physrevlett.110.081803] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Indexed: 06/01/2023]
Abstract
A study is presented of the mass and spin-parity of the new boson recently observed at the LHC at a mass near 125 GeV. An integrated luminosity of 17.3 fb(-1), collected by the CMS experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, is used. The measured mass in the ZZ channel, where both Z bosons decay to e or μ pairs, is 126.2 ± 0.6(stat) ± 0.2(syst) GeV. The angular distributions of the lepton pairs in this channel are sensitive to the spin-parity of the boson. Under the assumption of spin 0, the present data are consistent with the pure scalar hypothesis, while disfavoring the pure pseudoscalar hypothesis.
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Measurement of the sum of WW and WZ production with W+dijet events in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2283. [PMID: 25814853 PMCID: PMC4370803 DOI: 10.1140/epjc/s10052-013-2283-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/20/2012] [Indexed: 06/02/2023]
Abstract
A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at [Formula: see text] with the CMS detector at the LHC, corresponds to an integrated luminosity of 5.0 fb-1. The measured value of the sum of the inclusive WW and WZ cross sections is σ(pp→WW+WZ)=68.9±8.7 (stat.)±9.7 (syst.)±1.5 (lum.) pb, consistent with the standard model prediction of 65.6±2.2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes.
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50
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