Measurement of the charge ratio of atmospheric muons with the CMS detector

This is the pre-print version of this Article. The official published version can be accessed from the link below - Copyright @ 2010 ElsevierWe present a measurement of the ratio of positive to negative muon fluxes from cosmic ray interactions in the atmosphere, using data collected by the CMS detector both at ground level and in the underground experimental cavern at the CERN LHC. Muons were detected in the momentum range from 5 GeV/c to 1 TeV/c. The surface flux ratio is measured to be 1.2766 \pm 0.0032(stat.) \pm 0.0032 (syst.), independent of the muon momentum, below 100 GeV/c. This is the most precise measurement to date. At higher momenta the data are consistent with an increase of the charge ratio, in agreement with cosmic ray shower models and compatible with previous measurements by deep-underground experiments

Observation of a new Xi(b) baryon

The first observation of a new b baryon via its strong decay into Xi(b)^- pi^+ (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 inverse femtobarns. The known Xi(b)^- baryon is reconstructed via the decay chain Xi(b)^- to J/psi Xi^- to mu^+ mu^- Lambda^0 pi^-, with Lambda^0 to p pi^-. A peak is observed in the distribution of the difference between the mass of the Xi(b)^- pi^+ system and the sum of the masses of the Xi(b)^- and pi^+, with a significance exceeding five 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 Xi(b).Comment: Submitted to Physical Review Letter

Measurements of inclusive W and Z cross sections in pp collisions at root s=7 TeV

This is the pre-print version of the Published Article, which can be accessed from the link below - Copyright @ 2011 Springer VerlagMeasurements of inclusive W and Z boson production cross sections in pp collisions at sqrt(s)=7 TeV are presented, based on 2.9 inverse picobarns of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give sigma(pp to WX) times B(W to muon or electron + neutrino) = 9.95 \pm 0.07(stat.) \pm 0.28(syst.) \pm 1.09(lumi.) nb and sigma(pp to ZX) times B(Z to oppositely charged muon or electron pairs) = 0.931 \pm 0.026(stat.) \pm 0.023(syst.) \pm 0.102(lumi.) nb. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported

First measurement of hadronic event shapes in pp collisions at √s = 7 TeV

This is the Pre-Print version of the Article - Copyright @ 2011 ElsevierHadronic event shapes have been measured in proton-proton collisions at sqrt(s)=7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 inverse picobarns. Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production

Search for microscopic black hole signatures at the Large Hadron Collider

This is the Pre-Print version of the Article. The official published paper can be accessed from the link below - Copyright @ 2011 ElsevierA search for microscopic black hole production and decay 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 inverse picobarns. Events with large total transverse energy are analyzed for the presence of multiple high-energy jets, leptons, and photons, typical of a signal expected from a microscopic black hole. Good agreement with the expected standard model backgrounds, dominated by QCD multijet production, is observed for various final-state multiplicities. Limits on the minimum black hole mass are set, in the range 3.5 -- 4.5 TeV, for a variety of parameters in a model with large extra dimensions, along with model-independent limits on new physics in these final states. These are the first direct limits on black hole production at a particle accelerator.This work is supported by the FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)

Measurement of dijet angular distributions and search for quark compositeness in pp collisions at √s=7TeV

Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at root s = 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb(-1). The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Lambda(+) = 5.6 TeV (Lambda(-) = 6.7 TeV) for destructive (constructive) interference is obtained at the 95% confidence level

Myxomycetes associated with mountain tropical forests of bidoup nui ba and chu yang sin national parks (Dalat plateau, southern Vietnam)

A systematic survey for myxomycetes was carried out in 2011–2014 and 2017 at 106 localities in mountain tropical forests of Bidoup Nui Ba and Chu Yang Sin national parks (Dalat Plateau, southern Vietnam). In total, the survey yielded 652 records, of which 358 were field collections and 294 were collections obtained from 819 moist chamber cultures prepared with samples taken from the bark surface of living trees, ground and aerial litter and coarse woody debris. Determinations resulted in 105 taxa from 28 genera and 10 families. More than half (61) of all taxa were classified as rare. One collection of Badhamia could not be clearly assigned to any described species. Forty-two taxa were recorded for the first time for Vietnam and all were new for both national parks. The number of recorded taxa, increasing in a near-linear fashion with the number of field seasons, since sporulation activity of different species varies from year to year. Among the four natural vegetation types: middle mountain polydominant (A), mixed broadleaf-coniferous (B), middle mountain open pyrogenic coniferous (C), and high mountain cloud forest (D), completeness of the survey was highest for the first one. A pattern of decreasing diversity with increasing eleva-tion was found. In contrast, the specificity of myxomycete assemblages increased progressively in the sequence of vegetation types from A to D. In addition, artificial banana plantations (E) comprised the most distinctive but as well the least diverse myxomycete assemblage among all studied vegetation types. The taxonomic composition of myxomycete assemblages on major substrate groups differs from that in lowland forests, and species diversity increased from bark and aerial litter to ground litter and wood. © 2019 J. Cramer in Gebrüder Borntraeger Verlagsbuchhandlung, Stuttgart, Germany

Efficiency of nickel and chromium removal from child's body through physical activities

© 2020 EDIZIONIMINERVAMEDICA. BACKGROUND: At present, a large number of people live in unfavorable environmental conditions that adversely affect the health of the population, including children. Therefore, it is necessary to look for ways and create methods for removing harmful substances from the body, including physical culture means. METHODS: The following methods were used for the study: Analysis and synthesis of literary sources, atomic absorption analysis, pedagogical experiment, pedagogical observation. RESULTS: The research was conducted in a sanatorium located in a relatively environment-friendly area. More than 1000 preschool children participated in the study. To remove excess nickel and chromium we applied the following techniques in the experimental group: Hiking using cold-protective clothing, swimming in the pool, combined effects of hiking and saunas, saunas and swimming in the pool. The control group followed the standard program of the sanatorium. The results of the research showed that the most effective way for removing nickel from the body of children living in unfavorable environmental areas is physical activity in the pool; for the removal of chromium the most effective way is the combined effect of aquatic physical loads and thermal-air loading. CONCLUSIONS: The children from unfavorable environmental areas have higher content of heavy metals in the solid biological media; to reduce it, these metals must be removed through physical activity; the most effective way for removing nickel from the body of the children living in unfavorable environmental areas is the impact of physical exercises done in the pool; the most effective way for removing chromium from the body of the children living in unfavorable environmental areas is the complex impact of aquatic physical activity in combination with thermal-air loading