Upsilon (nS) polarizations versus particle multiplicity in pp collisions at root s=7 TeV

Peer reviewe

Search for Resonant Production of High-Mass Photon Pairs in Proton-Proton Collisions at root s=8 and 13 TeV

Peer reviewe

Measurements of the associated production of a Z boson and b jets in pp collisions at root s=8 TeV

Peer reviewe

Measurement of dijet azimuthal decorrelation in pp collisions at root s=8 TeV

Peer reviewe

Search for the standard model Higgs boson in the decay channel H to ZZ to 4 leptons in pp collisions at sqrt(s) = 7 TeV

A search for a Higgs boson in the four-lepton decay channel H to ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range 110 < mH < 600 GeV. The analysis uses data corresponding to an integrated luminosity of 4.7 inverse femtobarns recorded by the CMS detector in pp collisions at sqrt(s) = 7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m[4 leptons] > 100 GeV (with thirteen below 160 GeV), while 67.1 +/- 6.0 (9.5 +/-1.3) events are expected from background. The four-lepton mass distribution is consistent with the expectation of standard model background production of ZZ pairs. Upper limits at 95% confidence level exclude the standard model Higgs boson in the ranges 134-158 GeV, 180-305 GeV, and 340 -465 GeV. Small excesses of events are observed around masses of 119, 126, and 320 GeV, making the observed limits weaker than expected in the absence of a signal.Comment: Submitted to Physical Review Letter

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

Peer reviewe

Measurement of the t-channel single top quark production 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.Electroweak production of the top quark is measured for the first time in pp collisions at √s=7  TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36  pb-1. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi)  pb, consistent with the standard model expectation

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

Empirical Studies on Cash Payments

Cash is still the most common means of daily payments. The large number of cash payments is supported by a costly distribution system in which retailers, banks and central banks participate. Currency is issued in a range of bank note and coin denominations to facilitate efficiency in cash payments. The purpose of this thesis is to study the performance of a currency range in practice. It presents a number of empirical studies on cash payments at the individual payment level, whereby cash payments are viewed as the outcome of a choice process. This type of analysis calls for labor-intensive data collection methods and the development of a sophisticated econometric model. This thesis introduces such a model for cash payments, and it reviews its application to three unique data sets of cash payments. The data concern payments in the Netherlands before and after the transition from the guilder to the euro in 2002, and payments in an experimental setting. The estimation results allow for an assessment of the use of different bank note and coin denominations in cash payments, and of possible preferences for one of more denominations. Currency research generally approaches currency use from a macroeconomic point of view. The novelty of this thesis is that it contributes to currency research by focusing on individual cash payments.Jeanine Kippers (1973) obtained her master´s degree in econometrics from the Erasmus University Rotterdam in 1997. In the same year she was employed by De Nederlandsche Bank. She participated in the preparations of the cash changeover from guilder to euro in 2002, and contributed to the development of a European cash distribution system and the restructuring of the national distribution system. During her employment at the central bank she started her research on currency use, which resulted in several papers that have been published or are currently under review. In January 2004 she joined the Pensionand Insurance Supervisory authority, as a policy advisor in the (international) field of insurance supervision