Search for supersymmetry in pp collisions at 7 TeV in events with jets and missing transverse energy

Acknowledge support from: 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).A search for supersymmetry with R-parity conservation in proton–proton collisions at a centre-of-mass energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 pb−1 collected by the CMS experiment at the LHC. The search is performed in events with jets and significant missing transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary background, from standard model multijet production, is reduced by several orders of magnitude to a negligible level by the application of a set of robust kinematic requirements. With this selection, the data are consistent with the standard model backgrounds, namely t¯t, W + jet and Z + jet production, which are estimated from data control samples. Limits are set on the parameters of the constrained minimal supersymmetric extension of the standard model. These limits extend those set previously by experiments at the Tevatron and LEP colliders.23 páginas, 5 figuras, 2 tablas.-- Open access: This article is distributed under the terms of the Creative Commons Attribution License 3.0.-- CMS Collaboration: et al.Peer reviewe

Measurement of Wγ and Zγ production in pp collisions at √s = 7 TeV

21 páginas, 7 figuras, 2 tablas.-- Open access: This article is distributed under the terms of the Creative Commons Attribution License 3.0.-- CMS collaboration: et al.A measurement of Wγ and Zγ production in proton–proton collisions at √s = 7 TeV is presented. Results are based on a data sample recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 36 pb−1. The electron and muon decay channels of the W and Z are used. The total cross sections are measured for photon transverse energy Eγ T > 10 GeV and spatial separation from charged leptons in the plane of pseudorapidity and azimuthal angle R( ,γ) > 0.7, and with an additional dilepton invariant mass requirement of M > 50 GeV for the Zγ process. The following cross section times branching fraction values are found: σ(pp→Wγ + X) × B(W→ ν) = 56.3 ± 5.0(stat.) ± 5.0(syst.)±2.3(lumi.) pb and σ(pp→Zγ + X)×B(Z→ ) = 9.4±1.0(stat.)±0.6(syst.)±0.4(lumi.) pb. These measurements are in agreement with standard model predictions. The first limits on anomalous WWγ , ZZγ , and Zγγ trilinear gauge couplings at √s =7 TeV are set.Acknowledge support from: 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 UASLPFAI (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).Peer reviewe

Linear Superiorization for Infeasible Linear Programming

Linear superiorization (abbreviated: LinSup) considers linear programming (LP) problems wherein the constraints as well as the objective function are linear. It allows to steer the iterates of a feasibility-seeking iterative process toward feasible points that have lower (not necessarily minimal) values of the objective function than points that would have been reached by the same feasiblity-seeking iterative process without superiorization. Using a feasibility-seeking iterative process that converges even if the linear feasible set is empty, LinSup generates an iterative sequence that converges to a point that minimizes a proximity function which measures the linear constraints violation. In addition, due to LinSup's repeated objective function reduction steps such a point will most probably have a reduced objective function value. We present an exploratory experimental result that illustrates the behavior of LinSup on an infeasible LP problem.Comment: arXiv admin note: substantial text overlap with arXiv:1612.0653

Search for a W boson decaying to a muon and a neutrino in pp collisions at √s = 7 TeV

20 páginas, 4 figuras, 3 tablas.-- Open access: This article is distributed under the terms of the Creative Commons Attribution License 3.0.-- CMS Collaboration: et al.A new heavy gauge boson, W', decaying to a muon and a neutrino, is searched for in pp collisions at a centre-of-mass energy of 7 TeV. The data, collected with the CMS detector at the LHC, correspond to an integrated luminosity of 36 pb−1. No significant excess of events above the standard model expectation is found in the transverse mass distribution of the muon–neutrino system. Masses below 1.40 TeV are excluded at the 95% confidence level for a sequential standard-model-like W'. The W' mass lower limit increases to 1.58 TeV when the present analysis is combined with the CMS result for the electron channel.Acknowledge support from: 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 UASLPFAI (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).Peer reviewe

Informing, simulating experience, or both: A field experiment on phishing risks

Cybersecurity cannot be ensured with mere technical solutions. Hackers often use fraudulent emails to simply ask people for their password to breach into organizations. This technique, called phishing, is a major threat for many organizations. A typical prevention measure is to inform employees but is there a better way to reduce phishing risks? Experience and feedback have often been claimed to be effective in helping people make better decisions. In a large field experiment involving more than 10,000 employees of a Dutch ministry, we tested the effect of information provision, simulated experience, and their combination to reduce the risks of falling into a phishing attack. Both approaches substantially reduced the proportion of employees giving away their password. Combining both interventions did not have a larger impact

First microlensing candidate towards M31 from the Nainital Microlensing Survey

We report our first microlensing candidate NMS-E1 towards M31 from the data accumulated during the four years of Nainital Microlensing Survey. Cousin R and I band observations of ~13'x13' field in the direction of M31 have been carried out since 1998 and data is analysed using the pixel technique proposed by the AGAPE collaboration. NMS-E1 lies in the disk of M31 at \alpha = 0:43:33.3 and \delta = +41:06:44, about 15.5 arcmin to the South-East direction of the center of M31. The degenerate Paczy\'{n}ski fit gives a half intensity duration of ~59 days. The photometric analysis of the candidate shows that it reached R~20.1 mag at the time of maximum brightness and the colour of the source star was estimated to be (R-I)_0 ~ 1.1 mag. The microlensing candidate is blended by red variable stars; consequently the light curves do not strictly follow the characteristic Paczy\'{n}ski shape and achromatic nature. However its long period monitoring and similar behaviour in R and I bands supports its microlensing nature.Comment: no changes except typos corrected, to appear in A&

The POINT-AGAPE Survey: Comparing Automated Searches of Microlensing Events toward M31

Searching for microlensing in M31 using automated superpixel surveys raises a number of difficulties which are not present in more conventional techniques. Here we focus on the problem that the list of microlensing candidates is sensitive to the selection criteria or "cuts" imposed and some subjectivity is involved in this. Weakening the cuts will generate a longer list of microlensing candidates but with a greater fraction of spurious ones; strengthening the cuts will produce a shorter list but may exclude some genuine events. We illustrate this by comparing three analyses of the same data-set obtained from a 3-year observing run on the INT in La Palma. The results of two of these analyses have been already reported: Belokurov et al. (2005) obtained between 3 and 22 candidates, depending on the strength of their cuts, while Calchi Novati et al. (2005) obtained 6 candidates. The third analysis is presented here for the first time and reports 10 microlensing candidates, 7 of which are new. Only two of the candidates are common to all three analyses. In order to understand why these analyses produce different candidate lists, a comparison is made of the cuts used by the three groups...Comment: 28 pages, 24 figures, 9 table

Developing a Clinical Academic Career Pathway in a Community and Mental Health NHS Trust

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Background: Despite growing evidence of the impact that clinical academic staff have on patient care and clinical practice, there are disproportionately low numbers of nurses, allied health professionals and other healthcare professionals in clinical academic joint roles, compared to their medical colleagues. Aim: To describe the initial development of a clinical academic career pathway for nurses, allied health professionals and other healthcare professionals in a community and mental health NHS Trust. Methods: Kotter’s Model for Change was used to expand opportunities and research culture across an NHS Trust. Results: A variety of capacity and capability initiatives at different academic levels were created to support clinical academic development and to complement those available externally. These opportunities were underpinned by a research and development strategy, senior leadership buy-in, manager and clinical staff support, and targeted organisation-wide communication. Conclusion: The ongoing development of innovative clinical academic opportunities in the Trust, alongside greater support for staff interested in pursuing clinical academic careers, has resulted in a growing number of individuals successful in developing as clinical academic. This has led to a growth in research culture in the organisation and a greater understanding of what clinical academic staff can bring to patient care, the clinical service, and the wider organisation

Microlensing

Microlensing observations have now become a useful tool in searching for non--luminous astrophysical compact objects (brown dwarfs, faint stars, neutron stars, black holes and even planets). Originally conceived for establishing whether the halo of the Galaxy is composed of this type of objects, the ongoing searches are actually also sensitive to the dark constituents of other Galactic components (thin and thick disks, outer spheroid, bulge). We discuss here the present searches for microlensing of stars in the Magellanic Clouds and in the Galactic bulge (EROS, MACHO, OGLE and DUO collaborations). We analyse the information which can be obtained regarding the spatial distribution and motion of the lensing objects as well as about their mass function and their overall contribution to the mass of the Galaxy. We also discuss the additional signals, such as the parallax due to the motion of the Earth, the effects due to the finite source size and the lensing events involving binary objects, which can further constrain the lens properties. We describe the future prospects for these searches and the further proposed observations which could help to elucidate these issues, such as microlensing of stars in the Andromeda galaxy, satellite parallax measurements and infrared observations.Comment: Latex file, 59 p., 13 ps figures, to appear in Physics Reports (postcript file replaced by latex file

Mrk 421, Mrk 501, and 1ES 1426+428 at 100 GeV with the CELESTE Cherenkov Telescope

We have measured the gamma-ray fluxes of the blazars Mrk 421 and Mrk 501 in the energy range between 50 and 350 GeV (1.2 to 8.3 x 10^25 Hz). The detector, called CELESTE, used first 40, then 53 heliostats of the former solar facility "Themis" in the French Pyrenees to collect Cherenkov light generated in atmospheric particle cascades. The signal from Mrk 421 is often strong. We compare its flux with previously published multi-wavelength studies and infer that we are straddling the high energy peak of the spectral energy distribution. The signal from Mrk 501 in 2000 was weak (3.4 sigma). We obtain an upper limit on the flux from 1ES 1426+428 of less than half that of the Crab flux near 100 GeV. The data analysis and understanding of systematic biases have improved compared to previous work, increasing the detector's sensitivity.Comment: 15 pages, 14 figures, accepted to A&A (July 2006) August 19 -- corrected error in author lis