Interplay between telecommunications and face-to-face interactions - a study using mobile phone data

In this study we analyze one year of anonymized telecommunications data for over one million customers from a large European cellphone operator, and we investigate the relationship between people's calls and their physical location. We discover that more than 90% of users who have called each other have also shared the same space (cell tower), even if they live far apart. Moreover, we find that close to 70% of users who call each other frequently (at least once per month on average) have shared the same space at the same time - an instance that we call co-location. Co-locations appear indicative of coordination calls, which occur just before face-to-face meetings. Their number is highly predictable based on the amount of calls between two users and the distance between their home locations - suggesting a new way to quantify the interplay between telecommunications and face-to-face interactions

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

Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at √s=8 Tev

Peer reviewe

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

Measurement of Higgs boson production and properties in the WW decay channel with leptonic final states

Peer reviewe

Study of double parton scattering using W+2-jet events in proton-proton collisions at √s=7 TeV

Peer reviewe

Identification and Filtering of Uncharacteristic Noise in the CMS Hadron Calorimeter

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Measurements of the tt¯ charge asymmetry using the dilepton decay channel in pp collisions at √s=7 TeV

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Measurement of the t(t)over-bar production cross section in pp collisions at root s=7 TeV in dilepton final states containing a tau

The top quark pair production cross section is measured in dilepton events with one electron or muon, and one hadronically decaying tau lepton from the decay t (t) over bar -> (l nu(l))((sic)(h)nu((sic)))b (b) over bar, (l = e, mu). The data sample corresponds to an integrated luminosity of 2.0 fb(-1) for the electron channel and 2.2 fb(-1) for the muon channel, collected by the CMS detector at the LHC. This is the first measurement of the t (t) over bar cross section explicitly including tau leptons in proton- proton collisions at root s = 7 TeV. The measured value sigma(t (t) over bar) = 143 +/- 14(stat) +/- 22(syst) +/- 3(lumi) pb is consistent with the standard model predictions

Measurement of the inclusive jet cross section in pp collisions at √s = 7TeV

This is the pre-print version of the Published Article which can be accessed from the link below.The inclusive jet cross section is measured in pp collisions with a center-of-mass energy of 7 TeV at the Large Hadron Collider using the CMS experiment. The data sample corresponds to an integrated luminosity of 34  pb-1. The measurement is made for jet transverse momenta in the range 18–1100 GeV and for absolute values of rapidity less than 3. The measured cross section extends to the highest values of jet pT ever observed and, within the experimental and theoretical uncertainties, is generally in agreement with next-to-leading-order perturbative QCD predictions