HiggsToFourLeptonsEV in the ATLAS EventView Analysis Framework

ATLAS is one of the four experiments at the Large Hadron Collider (LHC) at CERN. This experiment has been designed to study a large range of physics topics, including searches for previously unobserved phenomena such as the Higgs Boson and super-symmetry. The physics analysis package HiggsToFourLeptonsEV for the Standard Model (SM) Higgs to four leptons channel with ATLAS is presented. The physics goal is to investigate with the ATLAS detector, the SM Higgs boson discovery potential through its observation in the four-lepton (electron and muon) final state. HiggsToFourLeptonsEV is based on the official ATLAS software ATHENA and the EventView (EV) analysis framework. EventView is a highly flexible and modular analysis framework in ATHENA and it is one of several analysis schemes for ATLAS physics user analysis. At the core of the EventView is the representative "view" of an event, which defines the contents of event data suitable for event-level physics analysis. The HiggsToFourLeptonsEV package, presented in this paper, prepares the data for the given analysis context on the Analysis Object Data (AOD) files, the event-level physics analysis is performed and finally the output information is written as an Ntuple which can be read in stand-alone ROOT. This paper describes the HiggsToFourLeptonsEV package and its structure as a collection of EVTools and EVModules. It also presents some illustrative results from the SM Higgs baseline analysis, like the SM Higgs into four-lepton mass reconstruction for a nominal Higgs mass of 130 GeV. The lepton reconstruction performance as well as the SM Higgs to four leptons analysis performance is studied in detail, in particular the dependence on kinematics, lepton reconstruction algorithms, isolation cuts and Higgs masses. Finally the paper discusses plans to adapt the code in order to produce Derived Physics Data (DPD) in POOL format which can be read in ROOT or ATHENA, thus following the ATLAS analysis model recommendations

Signal reconstruction in the EM end-cap calorimeter and check with cosmic data in the region 0< eta <3.2

In 2007, the electromagnetic end-cap calorimeter joined the ATLAS commissioning effort. Since then, calibration and cosmic muon runs are taken regularly, allowing to set-up, debug and test in situ the signal reconstruction. These are the first data in the 1.4500 MeV) have been used to perform a systematic and quantitative comparison between data and predicted physics pulse shapes in a coherent way over the entire calorimeter coverage, 0< eta <3.2. This represents the first attempt to unify barrel and end-cap in situ data in a common analysis. Results are similar in the barrel and the end-cap, only slightly worse for the latter as expected from its more complex geometry. This is the first proof of the quality of an ATLAS-like signal reconstruction in the end-caps, despite its challenging aspect, and gives confidence that the energy reconstruction is in good control over the complete electromagnetic calorimeter coverage 0< eta <3.2

Production of Z0 bosons in elastic and quasi-elastic ep collisions at HERA

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMThe production of Z0 bosons in the reaction ep →eZ0 p(∗), where p(∗) stands for a proton or a lowmass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb−1 of integrated luminosity. The Z0 was measured in the hadronic decay mode. The elasticity of the events was ensured by a cut on ηmax < 3.0, where ηmax is the maximum pseudorapidity of energy deposits in the calorimeter defined with respect to the proton beam direction. A signal was observed at the Z0 mass. The cross section of the reaction ep → eZ0 p(∗) was measured to be σ(ep → eZ0 p(∗)) =0.13 ± 0.06(stat.) ± 0.01(syst.) pb, in agreement with the Standard Model prediction of 0.16 pb. This is the first measurement of Z0 production in ep collisionsWe appreciate the contributions to the construction and maintenance of the ZEUS detector of many people who are not listed as authors. The HERA machine group and the DESY computing staff are especially acknowledged for their success in providing excellent operation of the collider and the data-analysis environment. We thank the DESY directorate for their strong support and encouragemen

Search for the Higgs boson decays H → ee and H → eμ in pp collisions at √s = 13 TeV with the ATLAS detector

Artículo escrito por un elevado número de autores, sólo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiera, y los autores pertenecientes a la UAMSearches for the Higgs boson decays H→eeand H→eμare performed using data corresponding to an integrated luminosity of 139 fb−1collected with the ATLAS detector in ppcollisions at √s=13 TeV at the LHC. No significant signals are observed, in agreement with the Standard Model expectation. For a Higgs boson mass of 125 GeV, the observed (expected) upper limit at the 95% confidence level on the branching fraction β(H→ee)is 3.6 ×10−4(3.5 ×10−4) and on β(H→eμ)is 6.2 ×10−5(5.9 ×10−5). These results represent improvements by factors of about five and six on the previous best limits on β(H→ee)and β(H→eμ)respectivelyWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, CRC and Compute Canada, Canada; COST, ERC, ERDF, Horizon 2020, and Marie Skłodowska-Curie Actions, European Union; Investissements d' Avenir Labex and Idex, ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and GIF, Israel; CERCA Programme Generalitat de Catalunya, Spain; The Royal Society and Leverhulme Trust, United Kingdo

Combination of searches for WW, WZ, and ZZ resonances in pp collisions at √s=8 TeV with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMThe ATLAS experiment at the CERN Large Hadron Collider has performed searches for new, heavy bosons decaying to WW, WZ and ZZ final states in multiple decay channels using 20.3 fb-1 of pp collision data at √s=8 TeV. In the current study, the results of these searches are combined to provide a more stringent test of models predicting heavy resonances with couplings to vector bosons. Direct searches for a charged diboson resonance decaying to WZ in the ℓνℓ'ℓ' (ℓ=μ, e), ℓℓqq-, ℓνqq- and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WZ bosons are compared with predictions of an extended gauge model with a heavy W' boson. In addition, direct searches for a neutral diboson resonance decaying to WW and ZZ in the ℓℓqq-, ℓνqq-, and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WW and ZZ bosons are compared with predictions for a heavy, spin-2 graviton in an extended Randall-Sundrum model where the Standard Model fields are allowed to propagate in the bulk of the extra dimensionWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azer-baijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Roma-nia; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States. In addition, individual groups and members have received support from BCKDF, the Canada Council, CANARIE, CRC, Com-pute Canada, FQRNT, and the Ontario Innovation Trust, Canada; EPLANET, ERC, FP7, Horizon 2020 and Marie Skłodowska-Curie Ac-tions, European Union; Investissements d’Avenir Labex and Idex, ANR, Region Auvergne and Fondation Partager le Savoir, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aris-teia programmes co-financed by EU-ESF and the Greek NSRF; BSF, GIF and Minerva, Israel; BRF, Norway; the Royal Society and Lever-hulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN and the ATLAS Tier-1facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) aneplad BNL (USA) and in the Tier-2 facilities worldwid

Homocitrato Molybdates and their Homologues

固氮酶是某些微生物在常温常压下固氮成氨的催化剂,其催化作用机理和化学模拟一直是国际上长期致力研究的对象。最新的钼铁蛋白单晶高分辨X光衍射分析表明，铁钼辅基的结构为MoFe7S9N(S-cys)(N-His)(homocit)。其中，Mo原子处于一端的角落位置上，并和3个μ3-硫配体、一个组氨酸和一个高柠檬酸配位，形成八面体的络合物。高柠檬酸以&#61537;-烷氧基和&#61537;-羧基直接同钼形成双齿配位。生物活性研究表明，含有高柠檬酸的固氮酶的固氮活性比其它羟基羧酸突变种的固氮酶活性强。但在固氮酶的固氮过程中，高柠檬酸发挥什么样的作用一直悬而未决。另外，过氧钼、钨配合物显示了独特的催化活...Nitrogenase catalyzes the reduction of dinitrogen to ammonia in the process of biological nitrogen fixation. In the past few decades, its catalytic mechanism and chemical simulation have been widely studied. The recent high resolution (1.16 &Aring;) X-ray structural analysis of the MoFe protein of nitrogenase reveals the FeMo-co (iron molybdenum cofactor) as a cage structure, MoFe7S9N(S-cys)(N-His...学位：理学博士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：B20012502

Measurements of W H and ZH production in the H → bb¯ decay channel in pp collisions at 13 TeV with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA

Measurement of the charge asymmetry in top-quark pair production in the lepton-plus-jets final state in pp collision data at √ s = 8 TeV with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMThis paper reports inclusive and differential measurements of the t ¯t charge asymmetry AC in 20.3 fb−1 of √s = 8 TeV pp collisions recorded by the ATLAS experiment at the Large Hadron Collider at CERN. Three differential measurements are performed as a function of the invariant mass, transverse momentum and longitudinal boost of the t ¯t system. The t ¯t pairs are selected in the single-lepton channels (e or μ) with at least four jets, and a likelihood fit is used to reconstruct the t ¯t event kinematics. A Bayesian unfolding procedure is performed to infer the asymmetry at parton level from the observed data distribution. The inclusive t ¯t charge asymmetry is measured to be AC = 0.009 ± 0.005 (stat. + syst.). The inclusive and differential measurements are compatible with the values predicted by the Standard ModelWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF,Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMTCR,MPOCR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; IN2P3-CNRS, CEADSM/ IRFU, France; GNSF, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom;DOEandNSF,United States ofAmerica. In addition, individual groups and members have received support from BCKDF, the Canada Council, CANARIE, CRC, Compute Canada, FQRNT, and the Ontario InnovationTrust, Canada; EPLANET, ERC, FP7, Horizon 2020 and Marie Skłodowska-Curie Actions, European Union; Investissements d’Avenir Labex and Idex, ANR, Region Auvergne and Fondation Partager le Savoir, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF; BSF, GIF and Minerva, Israel; BRF, Norway; the Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN and the ATLASTier- 1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA) and in the Tier-2 facilities worldwid

Study of hard double-parton scattering in four-jet events in pp collisions at √s = 7 TeV with the ATLAS experiment

Journal of High Energy Physics 2016.11 (2016): 110 reproduced by permission of Scuola Internazionale Superiore di Studi Avanzati (SISSA)Artículo escrito por muchos autores, sólo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración y los autores que firman como pertenecientes a la UAMInclusive four-jet events produced in proton-proton collisions at a centre-ofmass energy of √ s = 7 TeV are analysed for the presence of hard double-parton scattering using data corresponding to an integrated luminosity of 37.3 pb−1 , collected with the ATLAS detector at the LHC. The contribution of hard double-parton scattering to the production of four-jet events is extracted using an artificial neural network, assuming that hard double-parton scattering can be approximated by an uncorrelated overlaying of dijet events. For events containing at least four jets with transverse momentum pT ≥ 20 GeV and pseudorapidity |η| ≤ 4.4, and at least one having pT ≥ 42.5 GeV, the contribution of hard double-parton scattering is estimated to be fDPS = 0.092 +0.005 −0.011 (stat.) +0.033 −0.037 (syst.). After combining this measurement with those of the inclusive dijet and four-jet cross-sections in the appropriate phase space regions, the effective cross-section, σeff, was determined to be σeff = 14.9 +1.2 −1.0 (stat.) +5.1 −3.8 (syst.) mb. This result is consistent within the quoted uncertainties with previous measurements of σeff, performed at centre-of-mass energies between 63 GeV and 8 TeV using various final states, and it corresponds to 21+7 −6% of the total inelastic cross-section measured at √ s = 7 TeV. The distributions of the observables sensitive to the contribution of hard double-parton scattering, corrected for detector effects, are also providedWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, the Canada Council, CANARIE, CRC, Compute Canada, FQRNT, and the Ontario Innovation Trust, Canada; EPLANET, ERC, FP7, Horizon 2020 and Marie Sklodowska- Curie Actions, European Union; Investissements d’Avenir Labex and Idex, ANR, Région Auvergne and Fondation Partager le Savoir, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes cofinanced by EU-ESF and the Greek NSRF; BSF, GIF and Minerva, Israel; BRF, Norway; Generalitat de Catalunya, Generalitat Valenciana, Spain; the Royal Society and Leverhulme Trust, United Kingdo

Measurements of differential cross-sections in four-lepton events in 13 TeV proton-proton collisions with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA