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Three-dimensional nuclear architecture distinguishes thyroid cancer histotypes. Int J Cancer 2023; 153:1842-1853. [PMID: 37539710 DOI: 10.1002/ijc.34667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 06/30/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023]
Abstract
Molecular markers can serve as diagnostic tools to support pathological analysis in thyroid neoplasms. However, because the same markers can be observed in some benign thyroid lesions, additional approaches are necessary to differentiate thyroid tumor subtypes, prevent overtreatment and tailor specific clinical management. This applies particularly to the recently described variant of thyroid cancer referred to as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This variant has an estimated prevalence of 4.4% to 9.1% of all papillary thyroid carcinomas worldwide. We studied 60 thyroid lesions: 20 classical papillary thyroid carcinoma (CPTC), 20 follicular variant of PTC (FVPTC) and 20 NIFTP. We examined morphological and molecular features to identify parameters that can differentiate NIFTP from the other PTC subtypes. When blindly investigating the nuclear architecture of thyroid neoplasms, we observed that NIFTP has significantly longer telomeres than CPTC and FVPTC. Super-resolved 3D-structured illumination microscopy demonstrated that NIFTP is heterogeneous and that its nuclei contain more densely packed DNA and smaller interchromatin spaces than CPTC and FVPTC, a pattern that resembles normal thyroid tissue. These data are consistent with the observed indolent biological behavior and favorable prognosis associated with NIFTP, which lacks BRAFV600E mutations. Of note, next-generation thyroid oncopanel sequencing was unable to distinguish the thyroid cancer histotypes in our study cohort. In summary, our data suggest that 3D nuclear architecture can be a powerful analytical tool to diagnose and guide clinical management of NIFTP.
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Three-dimensional telomere profiles in papillary thyroid cancer variants: a pilot study. Bosn J Basic Med Sci 2021; 22:481-487. [PMID: 34882527 PMCID: PMC9162746 DOI: 10.17305/bjbms.2021.6639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022] Open
Abstract
Besides the two main histologic types of papillary thyroid carcinoma (PTC), the classical PTC (CL-PTC) and the follicular variant PTC (FV-PTC), several other variants are described. The encapsulated FV-PTC variant was recently reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) due to its similarities to benign lesions. Specific molecular signatures, however, are still unavailable. It is well known that improper DNA repair of dysfunctional telomeres may cause telomere-related genome instability. The mechanisms involved in the damaged telomere repair processing may lead to detrimental outcomes, altering the three-dimensional (3D) nuclear telomere and genome organization in cancer cells. This pilot study aimed to evaluate whether specific 3D nuclear telomere architecture might characterize NIFTP, potentially distinguishing it from other PTC histologic variants. Our findings demonstrate that 3D telomere profiles of CL-PTC and FV-PTC were different from NIFTP and that NIFTP more closely resembles follicular thyroid adenoma (FTA). NIFTP has longer telomeres than CL-PTC and FV-PTC samples, and the telomere length of NIFTP overlaps with that of the FTA histotype. In contrast, there was no association between BRAF expression and telomere length in all tested samples. These preliminary findings reinforce the view that NIFTP is closer to non-malignant thyroid nodules and confirm that PTC features short telomeres.
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Genomic Instability in Circulating Tumor Cells. Cancers (Basel) 2020; 12:cancers12103001. [PMID: 33081135 PMCID: PMC7602879 DOI: 10.3390/cancers12103001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/09/2020] [Accepted: 10/13/2020] [Indexed: 12/21/2022] Open
Abstract
Simple Summary In this review, we focus on recent advances in the detection and quantification of tumor cell heterogeneity and genomic instability of CTCs and the contribution of chromosome instability studies to genetic heterogeneity in CTCs at the single-CTC level. Abstract Circulating tumor cells (CTCs) can promote distant metastases and can be obtained through minimally invasive liquid biopsy for clinical assessment in cancer patients. Having both genomic heterogeneity and instability as common features, the genetic characterization of CTCs can serve as a powerful tool for a better understanding of the molecular changes occurring at tumor initiation and during tumor progression/metastasis. In this review, we will highlight recent advances in the detection and quantification of tumor cell heterogeneity and genomic instability in CTCs. We will focus on the contribution of chromosome instability studies to genetic heterogeneity in CTCs at the single-CTC level by discussing data from different cancer subtypes and their impact on diagnosis and precision medicine.
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It is ethical to diagnose a public figure one has not personally examined - CORRIGENDUM. Br J Psychiatry 2019; 214:239. [PMID: 30518438 DOI: 10.1192/bjp.2018.285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Should psychiatrists be able to speculate in the press or social media about their theories? John Gartner argues the risk to warn the public of concerns about public figures overrides the duty of confidentiality; whereas Alex Langford suggests this is beyond the ethical remit of psychiatric practice.Declaration of interestA.O'B is joint debates and analysis Editor of the British Journal of Psychiatry. J.G. is the founder of Duty To Warn, an association of mental health professionals who advocate the president's removal under the 25th Amendment on the grounds that he is psychologically unfit and dangerous.
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Abstract P2-04-02: Recognition of autologous neoantigens by tumor infiltrating lymphocytes derived from breast cancer metastases. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p2-04-02] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background & Translational Relevance: Adoptive transfer of tumor infiltrating lymphocytes (TIL) can effect long-term durable regression in patients with metastatic melanoma but has not been widely tested in common epithelial cancers. When examining the TIL of successfully treated patients with melanoma, a heterogeneous T cell population can be identified with reactivity against melanoma differentiation antigens, cancer germline antigens, and personalized non-synonymous somatic mutations. Common epithelial cancers, including breast cancer, express far fewer somatic mutations than melanoma, however, a patient with metastatic cholangiocarcinoma was treated with autologous CD4+ TIL enriched for neoantigen specificity and has experienced an ongoing partial response (>2 years). It is known that the presence of TIL on pathologic examination of triple-negative breast cancers is a positive prognostic marker for disease-free survival and overall survival. The identification of enriched populations of neoantigen-specific TIL could form the basis for personalized cell therapy for patients with metastatic breast cancer. This pilot study investigates the ability to grow TIL from breast cancer metastases, to identify personalized non-synonymous somatic mutations and potential neoantigens, and to adoptively transfer TIL into patients with breast cancer.
Methods: Eligible patients were evaluated and treated under IRB-approved protocols for tissue procurement, genomic testing, and adoptive cell transfer. Portions of resected tumors were placed in culture under standard TIL conditions. DNA was extracted from tumor and matched normal peripheral blood samples for whole exome sequencing (WES). Non-synonymous somatic mutations were identified and tested for potential immunogenicity.
Results: Nine patients have undergone surgical resection in this ongoing pilot study, and TIL was successfully grown from the tumors of all patients. All were primarily CD3+ (median 79%) with a small population of natural killer cells. Of the CD3+ cells, 7 of 9 patients had a predominantly CD4+ population (median CD4:CD8 ratio 2.2, range 0.4-5.8). With the exception of a single patient with inflammatory breast cancer, tumor purity allowed for WES of the tumors of eight patients, and non-synonymous somatic mutations were identified as potential neoantigens (median 96.5, range 71-148). Autologous T cell reactivity has been identified against tumor-specific mutations in 4 of 6 patients studied. The TIL of one patient demonstrated in vitro reactivity to a mutated form of RBPJ, a DNA-binding protein involved in Notch1 signaling. In addition, specimens obtained from this patient at autopsy contained the specific RBPJ mutation (RBPJ c.A611T) in every sampled tumor (n=16). Other patient-specific neoantigens identified by autologous reactivity include SLC3A2, KIAA0368, and a mutated TCRBV domain.
Conclusions: Tumor-infiltrating lymphocytes derived from metastatic breast cancer can react to tumor-specific non-synonymous somatic mutations in vitro. TIL grown from breast cancers are predominantly CD4+ and can form the basis of an adoptive cell transfer experimental approach to patients with metastatic breast cancer.
Citation Format: Goff SL, Zacharakis N, Assadipour Y, Prickett T, Gartner J, Somerville R, Black MA, Xu H, Chinnasamy H, Kriley I, Lu L, Statler M, Wunderlich J, Robbins PF, Rosenberg SA, Feldman SA. Recognition of autologous neoantigens by tumor infiltrating lymphocytes derived from breast cancer metastases [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-04-02.
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Identification of Neuroblastoma Subgroups Based on Three-Dimensional Telomere Organization. Transl Oncol 2016; 9:348-56. [PMID: 27567959 PMCID: PMC5006808 DOI: 10.1016/j.tranon.2016.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/05/2016] [Indexed: 12/19/2022] Open
Abstract
Using 3D telomere quantitative fluorescence in situ hybridization, we determined the 3D telomere organization of 74 neuroblastoma tissue samples. Hierarchical cluster analysis of the measured telomere parameters identified three subgroups from our patient cohort. These subgroups have unique telomere profiles based on telomere length and nuclear architecture. Subgroups with higher levels of telomere dysfunction were comprised of tumors with greater numbers of telomeres, telomeric aggregates, and short telomeres (P<.0001). Tumors with greater telomere dysfunction were associated with unfavorable tumor characteristics (greater age at diagnosis, unfavorable histology, higher stage of disease, MYCN amplification, and higher MYCN expression) and poor prognostic risk (P<.001). Subgroups with greater telomere dysfunction also had higher intratumor heterogeneity. MYCN overexpression in two neuroblastoma cell lines with constitutively low MYCN expression induced changes in their telomere profile that were consistent with increased telomere dysfunction; this illustrates a functional relationship between MYCN and 3D telomere organization. This study demonstrates the ability to classify neuroblastomas based on the level of telomere dysfunction, which is a novel approach for this cancer.
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A Systematic Review of the Quantity and Quality of Empirical Research Published in Four Pastoral Counseling Journals: 1975–1984. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/002234099004400205] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Compares the quantity and quality of research in pastoral counseling journals to that found in similar journals in psychiatry, geriatrics, and nursing. Concludes from the data that pastoral counseling research is less likely to state hypotheses, to use control groups, to state a sampling method, to report a response rate, to evaluate at more than a simple point in time, or to discuss limitations of the findings. Infers that, given these factors, pastoral counseling has failed to develop adequately as a behavioral science. Critical responses follow the article.
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MYCN overexpression is associated with unbalanced copy number gain, altered nuclear location, and overexpression of chromosome arm 17q genes in neuroblastoma tumors and cell lines. Genes Chromosomes Cancer 2015; 54:616-28. [PMID: 26171843 DOI: 10.1002/gcc.22273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/13/2015] [Accepted: 05/13/2015] [Indexed: 12/26/2022] Open
Abstract
MYCN amplification and MYCN overexpression are poor prognostic factors in neuroblastoma. Tumors with unbalanced chromosome arm 17q gain are often associated with MYCN amplification; however, the relationship between chromosome 17 copy number status and MYCN expression is not known. We investigated the relationship between MYCN expression and chromosome 17 copy number, nuclear location, and gene expression. By performing dual-colored fluorescence in situ hybridization on 16 primary neuroblastomas, we found that those with unbalanced gain of 17q have high MYCN expression, those with no gain have medium expression, and those with numerical gain have low expression (P < 0.0001). We also found that the nuclear location of 17q correlates with chromosome 17 copy number status: copies in tumors with unbalanced gain and no gain of chromosome 17 occupy a more central location than those in tumors with balanced gain (P < 0.0001). We show that a more central nuclear location of 17q coincides with increased expression of genes found within this chromosome arm. To further understand the association between MYCN expression and chromosome 17, we overexpressed MYCN in two low-expressing MYCN cell lines, SHEP and GIMEN. We found that both cell lines had an unbalanced gain of chromosome 17q, a more central nuclear location of the region and increased expression of the 17q genes. Therefore, this study indicates, for the first time, a functional relationship between MYCN overexpression and the gain of 17q in neuroblastoma.
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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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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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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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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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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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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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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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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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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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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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Measurement of the azimuthal anisotropy of neutral pions in Pb-Pb collisions at sqrt[s](NN)] = 2.76 TeV. PHYSICAL REVIEW LETTERS 2013; 110:042301. [PMID: 25166155 DOI: 10.1103/physrevlett.110.042301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Indexed: 06/03/2023]
Abstract
First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of sqrt[s(NN)] = 2.76 TeV are presented. The amplitudes of the second Fourier component (v(2)) of the π(0) azimuthal distributions are extracted using an event-plane technique. The values of v(2) are studied as a function of the neutral pion transverse momentum (p(T)) for different classes of collision centrality in the kinematic range 1.6<p(T) <8.0 GeV/c, within the pseudorapidity interval |η|<0.8. The CMS measurements of v(2) (p(T)) are similar to previously reported π(0) azimuthal anisotropy results from sqrt[s(NN)] = 200 GeV Au-Au collisions at RHIC, despite a factor of ∼ 14 increase in the center-of-mass energy. In the momentum range 2.5<p(T)<5.0 GeV/c, the neutral pion anisotropies are found to be smaller than those observed by CMS for inclusive charged particles.
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Evidence for associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:022003. [PMID: 23383893 DOI: 10.1103/physrevlett.110.022003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Indexed: 06/01/2023]
Abstract
Evidence is presented for the associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 4.9 fb(-1). The measurement is performed using events with two leptons and a jet originated from a b quark. A multivariate analysis based on kinematic properties is utilized to separate the tt background from the signal. The observed signal has a significance of 4.0σ and corresponds to a cross section of 16(-4)(+5) pb, in agreement with the standard model expectation of 15.6±0.4(-1.2)(+1.0) pb.
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Search for heavy neutrinos and W(R) bosons with right-handed couplings in a left-right symmetric model in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:261802. [PMID: 23368549 DOI: 10.1103/physrevlett.109.261802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for heavy, right-handed muon neutrinos, N(μ), and right-handed W(R) bosons, which arise in the left-right symmetric extensions of the standard model. The analysis is based on a 5.0 fb(-1) sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected by the CMS detector at the Large Hadron Collider. No evidence is observed for an excess of events over the standard model expectation. For models with exact left-right symmetry, heavy right-handed neutrinos are excluded at 95% confidence level for a range of neutrino masses below the W(R) mass, dependent on the value of M(W(R)). The excluded region in the two-dimensional (M(W(R)), M(N(μ)) mass plane extends to M(W(R))=2.5 TeV.
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Study of the Dijet mass spectrum in pp → W+jets events at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:251801. [PMID: 23368450 DOI: 10.1103/physrevlett.109.251801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Indexed: 06/01/2023]
Abstract
We report an investigation of the invariant mass spectrum of the two jets with highest transverse momentum in pp → W+2-jet and W+3-jet events to look for resonant enhancement. The data sample corresponds to an integrated luminosity of 5.0 fb(-1) collected with the CMS detector at sqrt[s] = 7 TeV. We find no evidence for the anomalous structure reported by the CDF Collaboration, and establish an upper limit of 5.0 pb at 95% confidence level on the production cross section for a generic Gaussian signal with mass near 150 GeV. Additionally, we exclude two theoretical models that predict a CDF-like dijet resonance near 150 GeV.
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26
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Measurement of the relative prompt production rate of χc2 and χc1 in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2012; 72:2251. [PMID: 25814834 PMCID: PMC4370953 DOI: 10.1140/epjc/s10052-012-2251-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/17/2012] [Indexed: 05/28/2023]
Abstract
A measurement is presented of the relative prompt production rate of χc2 and χc1 with 4.6 fb-1 of data collected by the CMS experiment at the LHC in pp collisions at [Formula: see text]. The two states are measured via their radiative decays χc→J/ψ+γ, with the photon converting into an e+e- pair for J/ψ rapidity |y(J/ψ)|<1.0 and photon transverse momentum pT(γ)>0.5 GeV/c. The measurement is given for six intervals of pT(J/ψ) between 7 and 25 GeV/c. The results are compared to theoretical predictions.
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27
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Observation of sequential Υ suppression in PbPb collisions. PHYSICAL REVIEW LETTERS 2012; 109:222301. [PMID: 23368113 DOI: 10.1103/physrevlett.109.222301] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Indexed: 06/01/2023]
Abstract
The suppression of the individual Υ(nS) states in PbPb collisions with respect to their yields in pp data has been measured. The PbPb and pp data sets used in the analysis correspond to integrated luminosities of 150 μb(-1) and 230 nb(-1), respectively, collected in 2011 by the CMS experiment at the LHC, at a center-of-mass energy per nucleon pair of 2.76 TeV. The Υ(nS) yields are measured from the dimuon invariant mass spectra. The suppression of the Υ(nS) yields in PbPb relative to the yields in pp, scaled by the number of nucleon-nucleon collisions, R(AA), is measured as a function of the collision centrality. Integrated over centrality, the R(AA) values are 0.56±0.08(stat)±0.07(syst), 0.12±0.04(stat)±0.02(syst), and lower than 0.10 (at 95% confidence level), for the Υ(1S), Υ(2S), and Υ(3S) states, respectively. The results demonstrate the sequential suppression of the Υ(nS) states in PbPb collisions at LHC energies.
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28
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Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:171803. [PMID: 23215177 DOI: 10.1103/physrevlett.109.171803] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Indexed: 06/01/2023]
Abstract
A search for physics beyond the standard model is performed in events with at least three jets and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of √s=7 TeV. No significant excess of events above the expected backgrounds is observed in 4.98 fb(-1) of data collected with the CMS detector at the Large Hadron Collider. The results are presented in the context of the constrained minimal supersymmetric extension of the standard model and more generically for simplified models. For the simplified models of gluino-gluino and squark-squark production, gluino masses below 1.0 TeV and squark masses below 0.76 TeV are excluded in case the lightest supersymmetric particle mass is below 200 GeV. These results significantly extend previous searches.
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29
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Measurement of the pseudorapidity and centrality dependence of the transverse energy density in Pb-Pb collisions at √(s(NN))=2.76 TeV. PHYSICAL REVIEW LETTERS 2012; 109:152303. [PMID: 23102301 DOI: 10.1103/physrevlett.109.152303] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Indexed: 06/01/2023]
Abstract
The transverse energy (E(T)) in Pb-Pb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (√(s(NN)) has been measured over a broad range of pseudorapidity (η) and collision centrality by using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dE(T)/dη) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities, the transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from η=0 to |η|=5.0. For the 5% most central collisions, the energy density per unit volume is estimated to be about 14 GeV/fm(3) at a time of 1 fm/c after the collision. This is about 100 times larger than normal nuclear matter density and a factor of 2.6 times higher than the energy density reported at √(s(NN))=200 GeV at the Relativistic Heavy Ion Collider.
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30
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Search for a W' or techni-ρ decaying into WZ in pp Collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:141801. [PMID: 23083236 DOI: 10.1103/physrevlett.109.141801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Indexed: 06/01/2023]
Abstract
A search is performed in pp collisions at sqrt[s]=7 TeV for exotic particles decaying via WZ to final states with electrons and muons. The data sample corresponds to an integrated luminosity of approximately 5 fb(-1). No significant excess is observed in the data above the expected standard model background. Upper bounds at 95% confidence level are set on the production cross section of the W' boson described by the sequential standard model and on the W' WZ coupling. W' bosons with masses below 1143 GeV are excluded. Limits are also set in the context of low-scale technicolor models, under a range of assumptions concerning the model parameters.
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31
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Search for a light pseudoscalar Higgs boson in the dimuon decay channel in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:121801. [PMID: 23005937 DOI: 10.1103/physrevlett.109.121801] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Indexed: 06/01/2023]
Abstract
The dimuon invariant mass spectrum is searched in the range between 5.5 and 14 GeV for a light pseudoscalar Higgs boson a, predicted in a number of new physics models, including the next-to-minimal supersymmetric standard model. The data sample used in the search corresponds to an integrated luminosity of 1.3 fb(-1) collected in pp collisions at √s = 7 TeV with the CMS detector at the LHC. No excess is observed above the background predictions and upper limits are set on the cross section times branching fraction σ × B(pp→a→μ(+)μ(-)) in the range of 1.5-7.5 pb. These results improve on existing bounds on the abb coupling for m(a) < m(Υ(1S)) and are the first significant limits for m(a) > m(Υ(3S)). Constraints on the supersymmetric parameter space are presented in the context of the next-to-minimal model.
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32
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Measurement of the electron charge asymmetry in inclusive W production in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:111806. [PMID: 23005617 DOI: 10.1103/physrevlett.109.111806] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Indexed: 06/01/2023]
Abstract
A measurement of the electron charge asymmetry in inclusive pp→W+X→eν+X production at sqrt[s]=7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 840 pb(-1). The electron charge asymmetry reflects the unequal production of W(+) and W(-) bosons in pp collisions. The electron charge asymmetry is measured in bins of the absolute value of electron pseudorapidity in the range of |η|<2.4. The asymmetry rises from about 0.1 to 0.2 as a function of the pseudorapidity and is measured with a relative precision better than 7%. This measurement provides new stringent constraints for parton distribution functions.
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33
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Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy. PHYSICAL REVIEW LETTERS 2012; 109:071803. [PMID: 23006358 DOI: 10.1103/physrevlett.109.071803] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Indexed: 06/01/2023]
Abstract
A search for new physics is performed in events with two same-sign isolated leptons, hadronic jets, and missing transverse energy in the final state. The analysis is based on a data sample corresponding to an integrated luminosity of 4.98 fb(-1) produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of 140 increase in integrated luminosity over previously published results. The observed yields agree with the standard model predictions and thus no evidence for new physics is found. The observations are used to set upper limits on possible new physics contributions and to constrain supersymmetric models. To facilitate the interpretation of the data in a broader range of new physics scenarios, information on the event selection, detector response, and efficiencies is provided.
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34
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Azimuthal anisotropy of charged particles at high transverse momenta in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV. PHYSICAL REVIEW LETTERS 2012; 109:022301. [PMID: 23030154 DOI: 10.1103/physrevlett.109.022301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Indexed: 06/01/2023]
Abstract
The azimuthal anisotropy of charged particles in Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (p(T)) range up to approximately 60 GeV/c. The data cover both the low-p(T) region associated with hydrodynamic flow phenomena and the high-p(T) region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with p(T), reaching a maximum around p(T)=3 GeV/c, and then to gradually decrease to almost zero, with the decline persisting up to at least pp(T)=40 GeV/c over the full centrality range measured.
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35
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Search for dark matter and large extra dimensions in pp collisions yielding a photon and missing transverse energy. PHYSICAL REVIEW LETTERS 2012; 108:261803. [PMID: 23004964 DOI: 10.1103/physrevlett.108.261803] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for new physics in the final state containing a photon (γ) and missing transverse energy (E[combininb /](T)). The data correspond to an integrated luminosity of 5.0 fb(-1) collected in pp collisions at √[s]=7 TeV by the CMS experiment. The observed event yield agrees with standard-model expectations for the γ+E[combininb /](T) events. Using models for the production of dark-matter particles (χ), we set 90% confidence level (C.L.) upper limits of 13.6-15.4 fb on χ production in the γ+E[combininb /](T) state. These provide the most sensitive upper limits for spin-dependent χ-nucleon scattering for χ masses (M(χ)) between 1 and 100 GeV. For spin-independent contributions, the present limits are extended to M(χ)<3.5 GeV. For models with 3-6 large extra dimensions, our data exclude extra-dimensional Planck scales between 1.64 and 1.73 TeV at 95% C.L.
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36
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Abstract
The observation of a new b baryon via its strong decay into Ξ(b)(-) π(+) (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at sqrt[s] = 7 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3 fb(-1). The known Ξ(b)(-) baryon is reconstructed via the decay chain Ξ(b)(-) → J/ψΞ(-) → μ(+) μ(-) Λ(0) π(-), with Λ(0) → pπ(-). A peak is observed in the distribution of the difference between the mass of the Ξ(b)(-) π(+) system and the sum of the masses of the Ξ(b)(-) and π(+), with a significance exceeding 5 standard deviations. The mass difference of the peak is 14.84 ± 0.74(stat) ± 0.28(syst) MeV. The new state most likely corresponds to the J(P) = 3/2(+) companion of the Ξ(b).
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37
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Measurement of thett¯production cross section in pp collisions ats=7 TeVin dilepton final states containing aτ. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.112007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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38
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P01.29. Pre-polarization conductance at Jing-Well acupoints on the hand is correlated with blood flow measured by laser doppler flowmetry. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012. [PMCID: PMC3373457 DOI: 10.1186/1472-6882-12-s1-p29] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Search for the standard model Higgs boson in the decay channel H→ZZ→4ℓ in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2012; 108:111804. [PMID: 22540464 DOI: 10.1103/physrevlett.108.111804] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Indexed: 05/31/2023]
Abstract
A search for a Higgs boson in the four-lepton decay channel H→ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range of 110<m(H)<600 GeV. The analysis uses data corresponding to an integrated luminosity of 4.7 fb(-1) recorded by the CMS detector in pp collisions at √s=7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m(4ℓ)>100 GeV (with 13 below 160 GeV), while 67.1±6.0 (9.5±1.3) events are expected from background. The four-lepton mass distribution is consistent with the expectation of standard model background production of ZZ pairs. Upper limits at 95% confidence level exclude the standard model Higgs boson in the ranges of 134-158 GeV, 180-305 GeV, and 340-465 GeV. Small excesses of events are observed around masses of 119, 126, and 320 GeV, making the observed limits weaker than expected in the absence of a signal.
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40
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Search for signatures of extra dimensions in the diphoton mass spectrum at the large hadron collider. PHYSICAL REVIEW LETTERS 2012; 108:111801. [PMID: 22540461 DOI: 10.1103/physrevlett.108.111801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Indexed: 05/31/2023]
Abstract
A search for signatures of extra spatial dimensions in the diphoton invariant-mass spectrum has been performed with the CMS detector at the LHC. No excess of events above the standard model expectation is observed using a data sample collected in proton-proton collisions at √s=7 TeV corresponding to an integrated luminosity of 2.2 fb(-1). In the context of the large-extra-dimensions model, lower limits are set on the effective Planck scale in the range of 2.3-3.8 TeV at the 95% confidence level. These limits are the most restrictive bounds on virtual-graviton exchange to date. The most restrictive lower limits to date are also set on the mass of the first graviton excitation in the Randall-Sundrum model in the range of 0.86-1.84 TeV, for values of the associated coupling parameter between 0.01 and 0.10.
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41
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Measurement of the rapidity and transverse momentum distributions ofZbosons inppcollisions at(s)=7 TeV. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.032002] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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42
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Search for a vectorlike quark with charge 2/3 in t+Z events from pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:271802. [PMID: 22243304 DOI: 10.1103/physrevlett.107.271802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Indexed: 05/31/2023]
Abstract
A search for pair-produced heavy vectorlike charge-2/3 quarks, T, in pp collisions at a center-of-mass energy of 7 TeV, is performed with the CMS detector at the LHC. Events consistent with the flavor-changing-neutral-current decay of a T quark to a top quark and a Z boson are selected by requiring two leptons from the Z-boson decay, as well as an additional isolated charged lepton. In a data sample corresponding to an integrated luminosity of 1.14 fb(-1), the number of observed events is found to be consistent with the standard model background prediction. Assuming a branching fraction of 100% for the decay T→tZ, a T quark with a mass less than 475 GeV/c(2) is excluded at the 95% confidence level.
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43
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Search for supersymmetry at the LHC in events with jets and missing transverse energy. PHYSICAL REVIEW LETTERS 2011; 107:221804. [PMID: 22182023 DOI: 10.1103/physrevlett.107.221804] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Indexed: 05/31/2023]
Abstract
A search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at √s=7 TeV by the CMS experiment at the LHC. The analyzed data sample corresponds to an integrated luminosity of 1.14 fb(-1). In this search, a kinematic variable α(T) is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. No excess of events over the standard model expectation is found. Exclusion limits in the parameter space of the constrained minimal supersymmetric extension of the standard model are set. In this model, squark masses below 1.1 TeV are excluded at 95% C.L. Gluino masses below 1.1 TeV are also ruled out at 95% C.L. for values of the universal scalar mass parameter below 500 GeV.
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44
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Search for new physics with a monojet and missing transverse energy in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:201804. [PMID: 22181725 DOI: 10.1103/physrevlett.107.201804] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Indexed: 05/31/2023]
Abstract
A study of events with missing transverse energy and an energetic jet is performed using pp collision data at a center-of-mass energy of 7 TeV. The data were collected by the CMS detector at the LHC, and correspond to an integrated luminosity of 36 pb(-1). An excess of these events over standard model contributions is a signature of new physics such as large extra dimensions and unparticles. The number of observed events is in good agreement with the prediction of the standard model, and significant extension of the current limits on parameters of new physics benchmark models is achieved.
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45
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Search for B(s)(0) → μ+ μ- and B(0) → μ+ μ- decays in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:191802. [PMID: 22181597 DOI: 10.1103/physrevlett.107.191802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Indexed: 05/31/2023]
Abstract
A search for the rare decays B(s)(0) → μ+ μ- and B(0) → μ+ μ- is performed in pp collisions at sqrt[s] = 7 TeV, with a data sample corresponding to an integrated luminosity of 1.14 fb(-1), collected by the CMS experiment at the LHC. In both cases, the number of events observed after all selection requirements is consistent with expectations from background and standard-model signal predictions. The resulting upper limits on the branching fractions are B(B(s)(0) → μ+ μ-) < 1.9 × 10(-8) and B(B(0) → μ+ μ-)<4.6 × 10(-9), at 95% confidence level.
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46
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Measurement of the inclusive jet cross section in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:132001. [PMID: 22026843 DOI: 10.1103/physrevlett.107.132001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Indexed: 05/31/2023]
Abstract
The inclusive jet cross section is measured in pp collisions with a center-of-mass energy of 7 TeV at the Large Hadron Collider using the CMS experiment. The data sample corresponds to an integrated luminosity of 34 pb(-1). The measurement is made for jet transverse momenta in the range 18-1100 GeV and for absolute values of rapidity less than 3. The measured cross section extends to the highest values of jet p(T) ever observed and, within the experimental and theoretical uncertainties, is generally in agreement with next-to-leading-order perturbative QCD predictions.
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47
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Search for three-jet resonances in pp collisions at square root(s)=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:101801. [PMID: 21981492 DOI: 10.1103/physrevlett.107.101801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Indexed: 05/31/2023]
Abstract
A search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 pb(-1). Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed using a signature-based approach. The number of expected standard model background events is found to be in good agreement with the observed events. Limits on the cross section times branching ratio are set in a model of gluino pair production with an R-parity-violating decay to three quarks, and the data rule out such particles within the mass range of 200 to 280 GeV/c2.
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48
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Measurement of the t-channel single top quark production cross section in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:091802. [PMID: 21929225 DOI: 10.1103/physrevlett.107.091802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Indexed: 05/31/2023]
Abstract
Electroweak production of the top quark is measured for the first time in pp collisions at √=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb⁻¹. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi) pb, consistent with the standard model expectation.
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49
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Indications of suppression of excited Υ states in Pb-Pb collisions at √(s(NN))=2.76 TeV. PHYSICAL REVIEW LETTERS 2011; 107:052302. [PMID: 21867063 DOI: 10.1103/physrevlett.107.052302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Indexed: 05/31/2023]
Abstract
A comparison of the relative yields of Υ resonances in the μ(+)μ(-) decay channel in Pb-Pb and pp collisions at a center-of-mass energy per nucleon pair of 2.76 TeV is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the Υ(2S) and Υ(3S) excited states to the Υ(1S) ground state in Pb-Pb and pp collisions, [Υ(2S+3S)/Υ(1S)](Pb-Pb)/[Υ(2S+3S)/Υ(1S)](pp), is found to be 0.31(-0.15)(+0.19)(stat)±0.03(syst). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1%.
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50
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