Measurement of the Zγ production cross section in pp collisions at 8 TeV and search for anomalous triple gauge boson couplings

Open Access, Copyright CERN, for the benefit of the CMS Collaboration. Article funded by SCOAP3.Abstract: The cross section for the production of Zγ in proton-proton collisions at 8 TeV is measured based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 19.5 fb−1. Events with an oppositely-charged pair of muons or electrons together with an isolated photon are selected. The differential cross section as a function of the photon transverse momentum is measured inclusively and exclusively, where the exclusive selection applies a veto on central jets. The observed cross sections are compatible with the expectations of next-to-next-to-leading-order quantum chromodynamics. Limits on anomalous triple gauge couplings of ZZγ and Zγγ are set that improve on previous experimental results obtained with the charged lepton decay modes of the Z boson

Search for lepton-flavour-violating decays of the Higgs boson

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Search for neutral resonances decaying into a Z boson and a pair of b jets or tau leptons

Peer reviewe

Hygiene habits and carriers in families with a child who has had typhoid fever Hábitos de higiene y portadores en familias que tuvieron un niño con fiebre tifoídea Hábitos de higiene e portadores em famílias que tiveram uma criança com febre tifóide

The relationship between asymptomatic shedding of bacterial enteropathogens and the hygiene habits of families who have had a child with typhoid fever (TF) are investigated. The sample was made up of 80 families: 40 families in which one child had had TF (Group A) and 40 in which no children or either of the parents had had a history of TF (Group B). In each group 20 families belonged to a low socieconomic status (SES) and 20 to a high SES. A structured interview was used to evaluate the SES and the hygiene habits of the child; observations were made to measure the hygiene habits of the family (toilet, kitchen and food preparation) and bacteriological studies (fecal samples and hand markers). Results show that carriers were more frequent in Group A than in Group B. The bacterial species found were significantly more numerous in Group A than in Group B (fecal samples: E. coli, the classic serotypes, Shigella ssp, and hand markers: E. coli). Families of Group A had higher carriage rates than those of Group B. Finally there exists a significantly higher association between inadequate hygiene habits and carrier families. These results show the need to teach specific habits of proper hygiene to the entire population, because the fact of belonging to the high SES does not in itself preclude inadequate hygiene habits.<br>El objetivo de este estudio fue investigar las relaciones entre la presencia de portadores de agentes bacteriales enteropatógenos y la calidad de los hábitos de higiene en familias que han tenido o no un niño con fiebre tifoídea (TF). La muestra estuvo formada por 80 familias: 40 en las que hubo un niño con FT (grupo A) y 40 en las que ni los niños y sus padres habían tenido una historia de FT (grupo B). En cada grupo 20 familias pertenecían al nivel socieconómico bajo (NSE) y 20 al NSE alto. Se usó una entrevista estructurada para evaluar el NSE, los hábitos de higiene del niño; observaciones estructuradas para medir los hábitos de higiene de la familia (baño, cocina y preparación de alimentos) y estudios bacteriológicos (muestras fecales y marcadores de mano). Los resultados señalan que los portadores fueron más frecuentes en el grupo A que en el B. Las especies bacterianas fueron significativamente más en el grupo A que en el B (muestras fecales: E. coli, serotipos clásicos, Shigella ssp, y marcadores de mano: E. coli). Las familias del grupo A tenían tasas más altas de portación que aquellas del grupo B. Finalmente existe una asociaión significativamente alta entre los hábitos inadecuados de higiene y las familias portadoras. Estos resultados muestran la necesidad de enseñar hábitos específicos de higiene adecuada a toda la población, porque el solo hecho de pertenecer al NSE alto no previene los hábitos de higiene inadecuados.<br>Objetivou-se estudar a relação entre qualidade dos hábitos de higiene e presença de portadores de agentes bacterianos enteropatogenos, em famílias que tiveram ou não, uma criança com febre tifóide (FT). A amostra esteve constituída por 80 famílias: 40 com a presença , em cada uma, de uma criança com FT (Grupo A) e 40 em que nem as crianças e seus pais nunca tiveram história de FT (Grupo B). Em cada grupo, 20 famílias pertenciam ao nível socioeconômico (NSE) baixo e 20 ao NSE alto. Para avaliar o NSE e os hábitos de higiene da criança foi utilizada entrevista estruturada; para medir os hábitos higiênicos da família (banho, cozinha e preparo dos alimentos) foram utilizadas observações estruturadas; e os estudos bacteriológicos foram realizados em amostras de fezes e marcadores de mão. Os resultados mostraram que no grupo A houve maior freqüência de portadores que no B. As espécies bacterianas foram significativamente mais freqüentes no Grupo A que no B (nas fezes: E. coli, serotipos clássicos, Shigella ssp; e em marcadores de mão: E. coli). As famílias do grupo A tiveram taxas altas de microorganismos que as do grupo B. Foi encontrada associação significativamente alta entre hábitos inadequados de higiene e as famílias portadoras. Os resultados mostraram a necessidade de ensinar hábitos específicos de higiene adequada a toda a população, pois somente o fato de pertencer ao NSE alto não previne os hábitos de higiene inadequados

Measurement of electroweak production of two jets in association with a Z boson in proton-proton collisions at root s=8 TeV

The purely electroweak (EW) cross section for the production of two jets in association with a Z boson, in proton–proton collisions at s√=8TeVs=8TeV , is measured using data recorded by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 19.7 fb-1fb-1 . The electroweak cross section for the ℓℓjjℓℓjj final state (with ℓ=eℓ=e or μμ and j representing the quarks produced in the hard interaction) in the kinematic region defined by Mℓℓ>50Mℓℓ>50 GeVGeV , Mjj>120Mjj>120 GeVGeV , transverse momentum pTj>25pTj>25 GeVGeV , and pseudorapidity |ηj|<5|ηj|<5 , is found to be σEW(ℓℓjj)=174±15(stat)±40(syst)\,fbσEW(ℓℓjj)=174±15(stat)±40(syst)\,fb , in agreement with the standard model prediction. The associated jet activity of the selected events is studied, in particular in a signal-enriched region of phase space, and the measurements are found to be in agreement with QCD predictions.BMWF ; FWF ; FNRS ; FWO ; CNPq ; CAPES ; FAPERJ ; FAPESP ; MEYS ; CERN ; CAS ; MoST ; NSFC ; COLCIENCIAS ; MSES ; RPF ; MoER ; SF0690030s09 ; ERDF ; Academy of Finland ; MEC ; HIP ; CEA ; CNRS/IN2P3 ; BMBF ; DFG ; HGF ; GSRT ; OTKA ; NKTH ; DAE ; DST ; IPM ; SFI ; INFN ; NRF ; WCU ; LAS ; CINVESTAV ; CONACYT ; SEP ; UASLP-FAI ; MSI ; PAEC ; MSHE ; NSC ; FCT ; JINR ; MON ; RosAtom ; RAS ; RFBR ; MSTD ; SEIDI ; CPAN ; Swiss Funding Agencies ; NSC ; ThEPCenter ; IPST ; NSTDA ; TUBITAK ; TAEK ; NASU ; STFC ; University of California Institute for Mexico and the United States ; the Marie-Curie programme and the European Research Council and EPLANET ; DOE and NSF ; the Leventis Foundation ; the A. P. Sloan Foundation ; the Alexander von Humboldt Foundation ; the Belgian Federal Science Policy Office ; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture ; the Agentschap voor Innovatie door Wetenschap en Technologie ; the Ministry of Education, Youth and Sports of Czech Republic ; the Agence Nationale de la Recherche ANR-12-JS05-002-01 ; the Council of Science and Industrial Research, India; the Compagnia di San Paolo ; the HOMING PLUS programme of Foundation for Polish Science, cofinanced by EU ; Regional Development Fund ; the Compagnia di San Paolo (Torino); and the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF ; and the National Priorities Research Program by Qatar National Research Fund

Party government : a rationalistic conception

Digitised version produced by the EUI Library and made available online in 2020

Building Cost Index 2004, August

Suomen virallinen tilasto (SVT

Violenza e diritto nell'era nucleare

A search has been performed for long-lived particles that could have come to rest within the CMS detector, using the time intervals between LHC beam crossings. The existence of such particles could be deduced from observation of their decays via energy deposits in the CMS calorimeter appearing at times that are well separated from any proton–proton collisions. Using a data set corresponding to an integrated luminosity of 18.6fb-1 of 8TeV proton–proton collisions, and a search interval corresponding to 281 h of trigger livetime, 10 events are observed, with a background prediction of 13.2+3.6−2.5 events. Limits are presented at 95 % confidence level on gluino and top squark production, for over 13 orders of magnitude in the mean proper lifetime of the stopped particle. Assuming a cloud model of R-hadron interactions, a gluino with mass ≲1000GeV and a top squark with mass ≲525GeV are excluded, for lifetimes between 1 μs and 1000s. These results are the most stringent constraints on stopped particles to date

Study of Z production in PbPb and pp collisions at sqrt(s[NN]) = 2.76 TeV in the dimuon and dielectron decay channels

see paper for full list of authorsInternational audienceThe production of Z bosons is studied in the dimuon and dielectron decay channels in PbPb and pp collisions at sqrt(s[NN]) = 2.76 TeV, using data collected by the CMS experiment at the LHC. The PbPb data sample corresponds to an integrated luminosity of about 150 inverse microbarns, while the pp data sample collected in 2013 at the same nucleon-nucleon centre-of-mass energy has an integrated luminosity of 5.4 inverse picobarns. The Z boson yield is measured as a function of rapidity, transverse momentum, and collision centrality. The ratio of PbPb to pp yields, scaled by the number of inelastic nucleon-nucleon collisions, is found to be 1.06 +/- 0.05 (stat) +/- 0.08 (syst) in the dimuon channel and 1.02 +/- 0.08 (stat) +/- 0.15 (syst) in the dielectron channel, for centrality-integrated Z boson production. This binary collision scaling is seen to hold in the entire kinematic region studied, as expected for a colourless probe that is unaffected by the hot and dense QCD medium produced in heavy ion collisions

Search for new phenomena in final states with two opposite-charge, same-flavor leptons, jets, and missing transverse momentum in pp collisions at √s = 13 TeV

Search results are presented for physics beyond the standard model in final states with two opposite-charge, same-flavor leptons, jets, and missing transverse momentum. The data sample corresponds to an integrated luminosity of 35.9 fb(-1) of proton-proton collisions at root s = 13TeV collected with the CMS detector at the LHC in 2016. The analysis uses the invariant mass of the lepton pair, searching for a kinematic edge or a resonant-like excess compatible with the Z boson mass. The search for a kinematic edge targets production of particles sensitive to the strong force, while the resonance search targets both strongly and electroweakly produced new physics. The observed yields are consistent with the expectations from the standard model, and the results are interpreted in the context of simplified models of supersymmetry. In a gauge mediated supersymmetry breaking (GMSB) model of gluino pair production with decay chains including Z bosons, gluino masses up to 1500-1770 GeV are excluded at the 95% confidence level depending on the lightest neutralino mass. In a model of electroweak chargino-neutralino production, chargino masses as high as 610 GeV are excluded when the lightest neutralino is massless. In GMSB models of electroweak neutralino-neutralino production, neutralino masses up to 500-650 GeV are excluded depending on the decay mode assumed. Finally, in a model with bottom squark pair production and decay chains resulting in a kinematic edge in the dilepton invariant mass distribution, bottom squark masses up to 980-1200 GeV are excluded depending on the mass of the next-to-lightest neutralino