D. M. Strom

Bio: D. M. Strom is an academic researcher from University of Oregon. The author has contributed to research in topics: Large Hadron Collider & Lepton. The author has an hindex of 176, co-authored 3167 publications receiving 194314 citations. Previous affiliations of D. M. Strom include University of Tokyo & University of Würzburg.

Study of the reaction e^{+}e^{-}->psi(2S)pi^{-}pi^{-} via initial state radiation at BaBar

Abstract: We study the process e+e−→ψ(2S)π+π− with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies at and near the Υ(nS) (n=2,3,4) resonances and correspond to an integrated luminosity of 520 fb−1. We investigate the ψ(2S)π+π− mass distribution from 3.95 to 5.95 GeV/c2, and measure the center-of-mass energy dependence of the associated e+e−→ψ(2S)π+π− cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the ψ(2S)π+π− mass distribution corresponding to the decay mode ψ(2S)→J/ψπ+π− yields a mass value of 4340±16 (stat) ±9 (syst) MeV/c2 and a width of 94±32 (stat) ±13 (syst) MeV for the first resonance, and for the second a mass value of 4669±21 (stat) ±3 (syst) MeV/c2 and a width of 104±48 (stat) ±10 (syst) MeV. In addition, we show the π+π− mass distributions for these resonant regions.

Measurements of the absolute branching fractions of B±→ K±Xcc̄

Abstract: We study the two-body decays of ${B}^{\ifmmode\pm\else\textpm\fi{}}$ mesons to ${K}^{\ifmmode\pm\else\textpm\fi{}}$ and a charmonium state ${X}_{c\overline{c}}$ in a sample of $210.5\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data from the BABAR experiment. We perform measurements of absolute branching fractions $\mathcal{B}({B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{X}_{c\overline{c}})$ using a missing mass technique, and report several new or improved results. In particular, the upper limit $\mathcal{B}\mathbf{(}{B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}X(3872)\mathbf{)}l3.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ at 90% C.L. and the inferred lower limit $\mathcal{B}\mathbf{(}X(3872)\ensuremath{\rightarrow}J/\ensuremath{\psi}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}\mathbf{)}g4.2%$ will help in understanding the nature of the recently discovered $X(3872)$.

Study of e+e-→pp̄ via initial-state radiation at BABAR

Abstract: The process e^+e^-→pp γ is studied using 469 fb^(-1) of integrated luminosity collected with the BABAR detector at the SLAC National Accelerator Laboratory, at an e^+e^- center-of-mass energy of 10.6 GeV. From the analysis of the pp invariant mass spectrum, the energy dependence of the cross section for e^+e^-→pp is measured from threshold to 4.5 GeV. The energy dependence of the ratio of electric and magnetic form factors, |G_E/G_M|, and the asymmetry in the proton angular distribution are measured for pp masses below 3 GeV. The branching fractions for the decays J/ψ→pp and ψ(2S)→pp are also determined.

The OPAL silicon-tungsten calorimeter front end electronics

Abstract: A pair of small angle silicon-tungsten (Si-W) calorimeters has been built to measure the luminosity to a precision better than 0.1% in the OPAL experiment at the Large Electron Positron (LEP) collider at CERN near Geneva. Each calorimeter contains 19 layers of tungsten (W) plates and silicon (Si) detectors, corresponding to a total of 22 radiation lengths, sampled by about 1 m/sup 2/ of detectors divided into 304/spl times/64 independently read out channels. A complete electronics system has been developed, from the preamplifier up to the VME read out and control interface. It includes a fast trigger based on analogue sums. This paper describes how a large number of channels have been implemented in a dense environment, thanks to the use of ASIC's directly bonded on the detector. >

QCD studies with e(+)e(-) annihilation data at 172-189 GeV

Abstract: We have studied hadronic events from $\mathrm{e^+e^-}$ annihilation data at centre-of-mass energies of $\sqrt{s}=$ 172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb $^{-1}$ . We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling $\alpha_s $ , the mean charged particle multiplicity $\langle n_{\mathrm{ch}}\rangle$ and the peak position $\xi_0$ in the $\xi_p=\ln(1/x_p)$ distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of $\alpha_s $ , $\langle n_{\mathrm{ch}}\rangle$ and $\xi_0$ are consistent with previous determinations at $\sqrt{s}=M_{\mathrm{Z^0}}$ .

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These