3,247 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
Delineation of management zones using mobile measurements of soil apparent electrical conductivity and multivariate geostatistical techniques
Site-specific management promotes the identification and management of areas within the field, which represent subfield regions with homogeneous characteristics (management zones). However,
determination of subfield areas is difficult because of the complex combination of factors which could affect crop yield. One possibility to capture yield variability is the use of soil physical properties to define
the management zones as they are related to plant available water.
With the aim of characterizing the spatial variability of the main soil physical variables and using this information to determine potential management zones, soil samples were taken from 70 locations in a
33-ha field in Badajoz, southwestern Spain. Firstly, accurate spatial distribution maps of the soil attributes were generated by using regression kriging as the most suitable algorithm in which exhaustive secondary information on soil apparent electrical conductivity (ECa) was incorporated. ECa
measurements were carried out with a Veris 3100 operating in both shallow (0â30 cm), ECs, and deep (0â90 cm), ECd,mode. Clay, coarse sand and fine sand were the soil physical properties which exhibited
higher correlation with ECa (positively correlated with the finer texture component, clay, and negatively correlated with the coarser ones, coarse and fine sands), particularly with ECs. Thus, this was the
secondary variable used to obtain the kriged maps. Later, principal component analysis and fuzzy cluster
classification were performed to delineate management zones, resulting in two subfields to be managed separately. This number of subfields was determined using the fuzzy performance index and normalized
classification entropy as the way to optimize the classification algorithm
Study of hard double-parton scattering in four-jet events in pp collisions at âs = 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)ArtĂculo escrito por muchos autores, sĂłlo se referencian el que aparece en primer lugar, el nombre del grupo de colaboraciĂłn y los autores que firman como pertenecientes a la UAMInclusive four-jet events produced in proton-proton collisions at a centre-ofmass
energy of â
s = 7 TeV are analysed for the presence of hard double-parton scattering
using data corresponding to an integrated luminosity of 37.3 pbâ1
, 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 â„ 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
â0.011 (stat.)
+0.033
â0.037 (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, Ïeff, was determined to be
Ïeff = 14.9
+1.2
â1.0
(stat.)
+5.1
â3.8
(syst.) mb. This result is consistent within the quoted uncertainties
with previous measurements of Ïeff, performed at centre-of-mass energies between
63 GeV and 8 TeV using various final states, and it corresponds to 21+7
â6% of the total inelastic
cross-section measured at â
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 dâAvenir Labex and Idex, ANR, RĂ©gion 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
Search for dark matter in association with a Higgs boson decaying to b-quarks in pp collisions at âs=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 fbâ1of 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 bbÂŻ 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 ZâČgauge boson mediating the interaction between dark matter and the Standard Model as well as a two-Higgs-doublet model containing an additional ZâČboson 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 MIZĆ , 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 SkĆodowska-Curie Actions, opean Union; Investissements dâAvenir Labex and Idex, ANR, RĂ©gion 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
Performance of the upgraded PreProcessor of the ATLAS Level-1 Calorimeter Trigger
ArtĂculo escrito por un elevado nĂșmero de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboraciĂłn, si lo hubiereThe PreProcessor of the ATLAS Level-1 Calorimeter Trigger prepares the analogue trigger signals sent from the ATLAS calorimeters by digitising, synchronising, and calibrating them to reconstruct transverse energy deposits, which are then used in further processing to identify event features. During the first long shutdown of the LHC from 2013 to 2014, the central components of the PreProcessor, the Multichip Modules, were replaced by upgraded versions that feature modern ADC and FPGA technology to ensure optimal performance in the high pile-up environment of LHC Run 2. This paper describes the features of the new Multichip Modules along with the improvements to the signal processing achieve
Establishment of a human cell-based in vitro battery to assess developmental neurotoxicity hazard of chemicals
Developmental neurotoxicity (DNT) is a major safety concern for all chemicals of the human exposome. However, DNT data from animal studies are available for only a small percentage of manufactured compounds. Test methods with a higher throughput than current regulatory guideline methods, and with improved human relevance are urgently needed. We therefore explored the feasibility of DNT hazard assessment based on new approach methods (NAMs). An in vitro battery (IVB) was assembled from ten individual NAMs that had been developed during the past years to probe effects of chemicals on various fundamental neurodevelopmental processes. All assays used human neural cells at different developmental stages. This allowed us to assess disturbances of: (i) proliferation of neural progenitor cells (NPC); (ii) migration of neural crest cells, radial glia cells, neurons and oligodendrocytes; (iii) differentiation of NPC into neurons and oligodendrocytes; and (iv) neurite outgrowth of peripheral and central neurons. In parallel, cytotoxicity measures were obtained. The feasibility of concentration-dependent screening and of a reliable biostatistical processing of the complex multi-dimensional data was explored with a set of 120 test compounds, containing subsets of pre-defined positive and negative DNT compounds. The battery provided alerts (hit or borderline) for 24 of 28 known toxicants (82% sensitivity), and for none of the 17 negative controls. Based on the results from this screen project, strategies were developed on how IVB data may be used in the context of risk assessment scenarios employing integrated approaches for testing and assessment (IATA).European Food Safety Authority (EFSA-Q-2018-00308), the Danish Environmental Protection Agency (EPA), Denmark, under the grant number MST-667-00205, the State Ministry of Baden-Wuerttemberg, Germany, for Economic Affairs, Labour and Tourism (NAM-Accept), the project CERST (Center for Alternatives to Animal Testing) of the Ministry for culture and science of the State of North-Rhine Westphalia, Germany (file number 233â1.08.03.03- 121972/131â1.08.03.03â121972), the European Chemical Industry Council Long-Range Research Initiative (Cefic LRI) under the project name AIMT11 and the BMBF (NeuroTool). It has also received funding from the European Union's Horizon 2020 research and innovation program under grant agreements No. 964537 (RISK-HUNT3R), No. 964518 (ToxFree), No. 101057014 (PARC) and No. 825759 (ENDpoiNTs)
Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA
Inclusive photoproduction of D*+- mesons has been measured for photon-proton
centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality
Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of
37 pb^-1. Total and differential cross sections as functions of the D*
transverse momentum and pseudorapidity are presented in restricted kinematical
regions and the data are compared with next-to-leading order (NLO) perturbative
QCD calculations using the "massive charm" and "massless charm" schemes. The
measured cross sections are generally above the NLO calculations, in particular
in the forward (proton) direction. The large data sample also allows the study
of dijet production associated with charm. A significant resolved as well as a
direct photon component contribute to the cross section. Leading order QCD
Monte Carlo calculations indicate that the resolved contribution arises from a
significant charm component in the photon. A massive charm NLO parton level
calculation yields lower cross sections compared to the measured results in a
kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure
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