4,464 research outputs found
Histogram comparison as a powerful tool for the search of new physics at LHC. Application to CMSSM
We propose a rigorous and effective way to compare experimental and
theoretical histograms, incorporating the different sources of statistical and
systematic uncertainties. This is a useful tool to extract as much information
as possible from the comparison between experimental data with theoretical
simulations, optimizing the chances of identifying New Physics at the LHC. We
illustrate this by showing how a search in the CMSSM parameter space, using
Bayesian techniques, can effectively find the correct values of the CMSSM
parameters by comparing histograms of events with multijets + missing
transverse momentum displayed in the effective-mass variable. The procedure is
in fact very efficient to identify the true supersymmetric model, in the case
supersymmetry is really there and accessible to the LHC
Search for Higgs and Z Boson Decays to J/ψγ and ϒ(nS)γ with the ATLAS Detector
Artículo escrito por muchos autores, sólo se referencian el primero, los autores que firman como Universidad Autónoma de Madrid y el grupo de colaboración en el caso de que aparezca en el artículoA search for the decays of the Higgs and Z bosons to J/ψγ and ϒ(nS)γ (n=1,2,3) is performed with pp collision data samples corresponding to integrated luminosities of up to 20.3 fb-1 collected at √s=8 TeV with the ATLAS detector at the CERN Large Hadron Collider. No significant excess of events is observed above expected backgrounds and 95% C.L. upper limits are placed on the branching fractions. In the J/ψγ final state the limits are 1.5×10-3 and 2.6×10-6 for the Higgs and Z boson decays, respectively, while in the ϒ(1S,2S,3S)γ final states the limits are (1.3,1.9,1.3)×10-3 and (3.4,6.5,5.4)×10-6, 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, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/ IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of Americ
Search for heavy lepton resonances decaying to a Z boson and a lepton in pp collisions at √s = 8 TeV with the ATLAS detector
Journal of High Energy Physics 2015.9 (2015): 108 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 UAMA search for heavy leptons decaying to a Z boson and an electron or a muon
is presented. The search is based on pp collision data taken at √
s = 8 TeV by the ATLAS
experiment at the CERN Large Hadron Collider, corresponding to an integrated luminosity
of 20.3 fb−1
. Three high-transverse-momentum electrons or muons are selected, with two
of them required to be consistent with originating from a Z boson decay. No significant
excess above Standard Model background predictions is observed, and 95% confidence level
limits on the production cross section of high-mass trilepton resonances are derived. The
results are interpreted in the context of vector-like lepton and type-III seesaw models. For
the vector-like lepton model, most heavy lepton mass values in the range 114–176 GeV
are excluded. For the type-III seesaw model, most mass values in the range 100–468 GeV
are excludedWe 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, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; RGC, Hong Kong SAR, China; ISF, MINERVA, GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of Americ
Search for production of vector-like quark pairs and of four top quarks in the lepton-plus-jets final state in pp collisions at √s=8 TeV with the ATLAS detector
Journal of High Energy Physics 2015.8 (2015): 105 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 UAMA search for pair production of vector-like quarks, both up-type (T) and downtype
(B), as well as for four-top-quark production, is presented. The search is based on
pp collisions at √
s = 8 TeV recorded in 2012 with the ATLAS detector at the CERN
Large Hadron Collider and corresponding to an integrated luminosity of 20.3 fb−1
. Data
are analysed in the lepton-plus-jets final state, characterised by an isolated electron or
muon with high transverse momentum, large missing transverse momentum and multiple
jets. Dedicated analyses are performed targeting three cases: a T quark with significant
branching ratio to a W boson and a b-quark (TT¯ → W b+X), and both a T quark and a
B quark with significant branching ratio to a Higgs boson and a third-generation quark
(TT¯ → Ht+X and BB¯ → Hb+X respectively). No significant excess of events above
the Standard Model expectation is observed, and 95% CL lower limits are derived on the
masses of the vector-like T and B quarks under several branching ratio hypotheses assuming
contributions from T → W b, Zt, Ht and B → W t, Zb, Hb decays. The 95% CL observed
lower limits on the T quark mass range between 715 GeV and 950 GeV for all possible values
of the branching ratios into the three decay modes, and are the most stringent constraints
to date. Additionally, the most restrictive upper bounds on four-top-quark production are
set in a number of new physics scenariosWe 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, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; RGC, Hong Kong SAR, China; ISF, MINERVA, GIF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MSTD,Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of Americ
Search for dark matter in association with a Higgs boson decaying to b-quarks in pp collisions at √s=13 TeV with the ATLAS detector
A search for dark matter pair production in association with a Higgs boson decaying to a pair of bottom quarks is presented, using 3.2 fb−1of pp collisions at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the LHC. The decay of the Higgs boson is reconstructed as a high-momentum bb¯ system with either a pair of small-radius jets, or a single large-radius jet with substructure. The observed data are found to be consistent with the expected backgrounds. Results are interpreted using a simplified model with a Z′gauge boson mediating the interaction between dark matter and the Standard Model as well as a two-Higgs-doublet model containing an additional Z′boson which decays to a Standard Model Higgs boson and a new pseudoscalar Higgs boson, the latter decaying into a pair of dark matter particlesWe acknowledge the support of ANPCyT, Argentina; YerPhI, Ar-menia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbai-jan; 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 Re-public; 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 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, the Canada Council, CANARIE, CRC, Compute Canada, FQRNT, and the Ontario Innovation Trust, Canada; EPLANET, ERC, FP7, Horizon 2020 and Marie Skłodowska-Curie Actions, opean Union; Investissements d’Avenir Labex and Idex, ANR, Région Au-vergne 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; Generalitat de Catalunya, Generalitat Valen-ciana, Spain; the Royal Society and Leverhulme Trust, United Kingdo
Vinhos que pensam - parte ii|iii: utilização da condutividade elétrica aparente do solo na instalação e gestão das culturas: exemplificação na vinha
Vinhos que pensam - parte ii|iii: utilização da condutividade elétrica aparente do solo na instalação e gestão das culturas: exemplificação na vinh
Vinhos que pensam - parte i|iii: gestão do vigor vegetativo da vinha a partir de sensores ativos multiespectrais próximos
Vinhos que pensam - parte i|iii: gestão do vigor vegetativo da vinha a partir de sensores ativos multiespectrais próximo
Avascular necrosis of the hip and diffuse idiopathic skeletal hyperostosis during long-term isotretinoin treatment of epidermolytic ichthyosis due to a novel deletion mutation in KRT10
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
- …
