On b- and tau-multiplicities per event in SUSY (mSUGRA) and instrumental implications

We investigate the probability to find a b or tau in SUSY production with the mSUGRA model. We find that in the entire parameter space the probability per event to find a b-jet of E_T^b > 50 GeV within CMS acceptance (eta < 2.4) is significant for all tan(beta), varying from a 10 % level to 90 % depending on the m_0, m_1/2 region. The probabilities per event to find a tau with the same kinematical cuts is also significant and it increases sharply with tan(beta). These findings point to the central role a microvertex device would play in case that SUSY (mSUGRA) is indeed realized in nature and found at the LHC. First investigations done in the context of the more general MSSM scenario confirm the findings based on mSUGRA.Comment: 19 pages, 13 figures, 3 table

The CMS detector and physics at the LHC

We discuss the physics issues at the LHC, the CMS detector, one of the two general purpose detectors planned at the LHC, and the expected physics performance of LHC detectors in the search for SM and SUSY Higgs bosons, some SUSY particle searches and some possibilities in B and heavy ion physics

Proučavanje H → ZZ → 4ℓ ± pomoću cjelovite geant simulacije detektora CMS

We study the detection of H → ZZ → 4ℓ ± in the CMS detector at the nominal LHC energy √ s = 14 TeV and the possibility for an early detection at a reduced energy √ s = 10 TeV. A systematic study of the multi–lepton mass resolution is performed, including effects of internal and external radiation through detailed GEANT simulations. At √ s = 14 TeV, an integrated luminosity of 104 pb−1 allows exploration at a ≥ 5σ significance level a mass range from mH ≈ 2mZ up to mH ≈ 400 GeV. For 105 pb−1 , the mass reach is about 650 GeV. At √ s = 10 TeV, an integrated luminosity of 104 pb−1 does not provide a 5σ significance level for any value of Higgs mass, and 2 × 104 pb−1 alows one to explore a mass range from mH ≈ 2mZ to ≈ 350 GeV at ≥ 5σ level.Proučava se detekcija H → ZZ → 4ℓ ± procesa u detektoru CMS na nominalnoj energiji LHC √ s = 14 TeV i mogućnost ranijeg opažanja na manjoj energiji od 10 TeV. Studija uključuje instrumentalne efekte za elektrone i muone i njihov utjecaj na razlučivanje višeleptonskih masa

Eksperiment CMS na LHC-u

We discuss the current status of the Large Hadron Collider (LHC) machine, the progress on the construction of the CMS detector and some expectations for physics studies and searches at the LHC.Opisujemo sadašnje stanje gradnje ubrzivača LHC, napredak u gradnji detektora CMS i neka očekivanja fizičkih istraživanja i traganja na LHC-

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Performance and Operation of the CMS Electromagnetic Calorimeter

The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

Measurements of the pp → ZZ production cross section and the Z → 4ℓ branching fraction, and constraints on anomalous triple gauge couplings at √s = 13 TeV

Four-lepton production in proton-proton collisions, pp -> (Z/gamma*)(Z/gamma*) -> 4l, where l = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The ZZ production cross section, sigma(pp -> ZZ) = 17.2 +/- 0.5 (stat) +/- 0.7 (syst) +/- 0.4 (theo) +/- 0.4 (lumi) pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60 4l) = 4.83(-0.22)(+0.23) (stat)(-0.29)(+0.32) (syst) +/- 0.08 (theo) +/- 0.12(lumi) x 10(-6) for events with a four-lepton invariant mass in the range 80 4GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ. couplings at 95% confidence level: -0.0012 < f(4)(Z) < 0.0010, -0.0010 < f(5)(Z) < 0.0013, -0.0012 < f(4)(gamma) < 0.0013, -0.0012 < f(5)(gamma) < 0.0013

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis