Bulletin of the American Physical Society
2007 APS April Meeting
Volume 52, Number 3
Saturday–Tuesday, April 14–17, 2007; Jacksonville, Florida
Session F1: Poster Session I |
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Sponsoring Units: APS Room: Hyatt Regency Jacksonville Riverfront Terrace Pavilion, 5:30pm - 6:45pm |
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F1.00001: PARTICLES IN FIELDS |
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F1.00002: Exclusive radiative penguin decays of $B$ mesons at BaBar Stephen Sekula We present recent experimental studies of $b \to s \gamma$ and $b \to d \gamma$ transitions with the BaBar detector at the SLAC PEP-II $B$ Factory. These decays proceed through loop topologies at leading order and provide a probe of New Physics at high mass scales. Contributions from virtual new particles may alter the decay rate, $CP$ asymmetry and other observable quantities. The focus of this talk are measurements of $B$ decays to $K^*\gamma$, $\rho \gamma$, and $\omega \gamma$ final states. [Preview Abstract] |
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F1.00003: Tau leptons as a probe for new physics at LHC Sarah Demers The tau leptons identification with ATLAS experiment will be possible already at the early start of the data taking. The copius production of W and Z bosons decaying to the tau leptons will provide unique possibility to calibrate and understand identification~ of hadronically decaying tau's above the QCD background already with few hundreds of pb-1. With integrated luminosity of tens of fb-1, tau leptons will become an excellent probe for searching for the SM and MSSM Higgs boson, SUSY~ or extra dimensions. In the talk we review prospect for early physics and searches scenarios involving tau leptons. [Preview Abstract] |
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F1.00004: CMS Detector Sensitivity to the Standard Model Higgs Boson in $\mathrm{H}\to\mathrm{ZZ^{(\ast)}}\to4{\rm leptons}$ Decay Channel Alexey Drozdetskiy Presented are the results of the analysis of the CMS detector sensitivity to the Standard Model Higgs boson in its 4-lepton decay channel, $\mathrm{H}\to\mathrm{ZZ^{(\ast)}}\to4{\rm leptons}$, in the Higgs boson mass range from 115-600 GeV. The studies are based on the most recent full CMS detector simulation and mimic the real data analysis with the most critical calibrations extracted from ``data'' and all systematic uncertainties explicitly evaluated and taken into account. [Preview Abstract] |
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F1.00005: Signatures of Hidden Valley Higgs decays Daniel Ventura, Laura Bodine In this talk we present results from a preliminary study of a potential Higgs discovery channel involving Hidden Valley particles decaying in the ATLAS detector at the Large Hadron Collider. In the Hidden Valley Model* proposed by M. Strassler and K. Zurek, the Higgs can decay to neutral, light, long-lived particles that subsequently decay to Standard Model particles. We present results of an ongoing study of the ability to detect this Higgs decay channel with the ATLAS detector. We will discuss triggering issues arising from highly displaced vertices and jets with few associated tracks. * M Strassler and K. Zurek hep-ph/0605193 [Preview Abstract] |
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F1.00006: ABSTRACT HAS BEEN MOVED TO X14.00009 |
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F1.00007: Direct Measurement of the $W$ Boson Width Sarah Malik, Valeria Bartsch, Daniel Beecher, Ilija Bizjak, Mark Lancaster, Emily Nurse, Troy Vine, David Waters We present a direct measurement of the $W$ boson width using 370 $pb^{-1}$ and 330 $pb^{-1}$ of data collected with the CDF II detector for the electron and muon decay channels respectively. The measurement is made by fitting to the tail of the transverse mass distribution, exploiting the slower fall-off of the Breit Wigner width component compared to the Gaussian resolution component. [Preview Abstract] |
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F1.00008: ABSTRACT WITHDRAWN |
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F1.00009: ABSTRACT HAS BEEN MOVED TO J14.00001 |
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F1.00010: Top Quark Mass Measurement in Lepton+Jets Channel using a Multivariate Technique at CDF John Freeman We present a measurement of the top quark mass using the Run II data collected with the CDF detector at Fermilab. The $t\bar{t}$ events produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV are reconstructed in the lepton+jets channel. Using a matrix element method designed to account for imperfect resolution of a given event's kinematic measurements, we calculate a likelihood for each event to be a top candidate over a range of possible top masses. Adding a novel method to account for background employing additional kinematics variables we derive a value for the top mass. [Preview Abstract] |
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F1.00011: Measurement of the top quark mass at D0 using the neutrino weighting method on dilepton events Dan Boline We report on the measurement of the top quark mass using $t\bar {t}$ candidates in the dilepton final states. The kinematics of these events are solved for a range of assumed top quark masses, and the relative likelihood of each solution is assessed. Information from the complete set of events is combined in a maximum likelihood fit to extract the top quark mass. [Preview Abstract] |
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F1.00012: Search for Single Top Quark Production at CDF II Sarah Budd The electroweak production of single top quarks has been sought after since the discovery of the top quark more than 10 years ago. The measurement of the cross section for single top quarks provides sensitivity to the CKM element $V_{tb}$ and is sensitive to various models of physics beyond the standard model. CDF uses several multivariate techniques to search for s-channel and t-channel single-top production, as well as the combined process, using 1 fb$^{-1}$ of proton-antiproton collision data. Results are given for two of these techniques, one using likelihood functions and one using neural networks. [Preview Abstract] |
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F1.00013: ABSTRACT WITHDRAWN |
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F1.00014: Calibration of the PrimEx Experimental Setup via a Precision Measurement of the Compton Cross Section Jing Feng Chiral symmetry and the chiral anomaly are fundamental in QCD. The PrimEx collaboration recently carried out a new measurement on the neutral pion lifetime to test chiral perturbation theory prediction at a few percentage accuracy. The major challenge of this experiment is to achieve the high precision projected. In order to calibrate the overall systematic error, we carried out a measurement on a well-known atomic electron Compton cross section using the PrimEx experimental setup. This is the first precision measurement on this fundamental QED process in the few GeV energy range, and will shed light on the higher order corrections to the Klein-Nishina formula. A preliminary result will be presented in this talk. [Preview Abstract] |
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F1.00015: An independent check of the CVC hypothesis in the charged pion via the radiative pion decay $\pi^{+} \to {\rm e}^{+} \nu \gamma$ Maxim Bychkov The PIBETA experiment has collected the world largest sample of the positive pion and muon decays to date, using Paul Scherrer Institute meson facility in Switzerland. The radiative pion decay $\pi^{+} \to {\rm e}^{+} \nu \gamma$ is the key element of the PIBETA data stream analysis. This decay is sensitive to the structure of the charged pions and serves as an independent check of the CVC hypothesis. Measuring this decay is experimentally challenging and it provides much deeper level of understanding of the systematic effects in the PIBETA detector. This talk will concentrate on the combined analysis of $\pi^{+} \to {\rm e}^{+} \nu \gamma$ decay in the entire PIBETA data set. Particular emphasis will be given to the new precise determination of the charged pion vector form factor $F_{V}$ and its dependence on the momentum transfered to the lepton pair. [Preview Abstract] |
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F1.00016: New Results for the Production of $\Lambda$ and $\Sigma^0$ Hyperons in antineutrino scattering from proton by using new form factors data Lingling Wen, Stephan Mintz We obtain total and differential cross sections for the strangeness changing charged current reactions $\bar{\nu_L} + p\longrightarrow \Lambda + L^+$ and $\bar{\nu_L} + p\longrightarrow \Sigma^0 + L^+$ where $L$ is a charged lepton, either an electron, muon or tau. We do this by making use of the standard dipole form factors normally used and for new form factors recently obtained from recoil proton measurements in electron-proton electromagnetic scattering. We also obtain the contributions of the individual form factors to the total and differential cross sections for both sets of form factors. We find that the differential and total cross sections for $\Lambda$ production change only slightly between the two sets of form factors but that the differential and total cross sections change substantially for $\Sigma^0$ production. We discuss the possibility of distinguishing between the two cases for the experiments planned by the MINER$\nu$A Collaboration. [Preview Abstract] |
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F1.00017: e-Science for High Energy Physics in Korea Kihyeon Cho We report experiences and results of the integration and utilization of e-Science for High Energy Physics in Korea. An overview is given of the current and planned uses of cyber infrastructure which contains computing, storage, network and Grid service infrastructure in Korea. We will also report the experiences in operating Grid farms and researches on EGEE for LHC experiments. [Preview Abstract] |
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F1.00018: A New Measurement of the Muon Lifetime and the Determination of the Fermi Coupling Constant Kevin Giovanetti A new measurement of the muon lifetime, \textit{$\tau $}$_{\mu }$, at the 11 ppm level will be reported. This is the first result from the MuLan experiment, which is pursuing the ambitious goal of a 1~ppm determination of the muon lifetime---a 20-fold improvement. The experiment is motivated by recent theoretical improvements in extracting the Fermi coupling constant $G_{F}$, from the measured lifetime; the theoretical uncertainty is now less than 1~ppm. The coupling constant $G_{F}$ is an essential parameter of the standard model and represents the strength of the weak interaction. Progress, highlights and future plans for this experiment will also be discussed. [Preview Abstract] |
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F1.00019: Analysis of Systematic Errors in the MuLan Muon Lifetime Experiment Ronald McNabb The MuLan experiment seeks to measure the muon lifetime to 1 ppm. To achieve this level of precision a multitude of systematic errors must be investigated. Analysis of the 2004 data set has been completed, resulting in a total error of 11 ppm(10 ppm statistical, 5 ppm systematic). Data obtained in 2006 are currently being analyzed with an expected statistical error of 1.3 ppm. This talk will discuss the methods used to study and reduce the systematic errors for the 2004 data set and improvements for the 2006 data set which should reduce the systematic errors even further. [Preview Abstract] |
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F1.00020: Measurement of Relative Fragmentation Fractions of Bottom Hadrons with CDF Philippe Roy Fragmentation is the process by which bare quarks dress themselves up as hadrons. Since we cannot get reliable calculations of this process using perturbative QCD, the fragmentation properties of quarks must be obtained empirically. We report the first measurement of relative fragmentation fractions of $b$~quarks to $B$~hadrons using fully reconstructed decays of $B^{0}$, $B^0_{s}$ and $\Lambda_{b}$ in 1.4~fb$^{-1}$ of data taken with the CDF\,II detector. In order to reduce systematic uncertainties, arising from the poor knowledge of the $b$~quark production cross section in $p\bar p$~collisions or absolute determinations of trigger and tracking efficiencies, ratios of $b$~quark fragmentation fractions are measured. [Preview Abstract] |
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F1.00021: ABSTRACT WITHDRAWN |
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F1.00022: A search for prompt $\chi_{c}$ and $X(3872)$ production in $e^+e^-$ annihilations Woochun Park A search for prompt $\chi_{c}$ and $X(3872)$ production in $e^+e^-$ annihilations is performed using 386 fb$^{-1}$ of data collected around a center-of-mass energy $\sqrt{s} \approx 10.6$ GeV with the BaBar detector. The $\chi_{c}$ and $X(3872)$ candidates are reconstructed using their radiative decay $\gamma J/\psi$ with $J/\psi\rightarrow e^+e^-$ or $\mu^+\mu^-$. We present preliminary results. [Preview Abstract] |
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F1.00023: Antineutrinos at MINOS Alexander Himmel The NUMI muon neutrino beam used by MINOS has a 6{\%} antineutrino component. Using this intrinsic antineutrino flux, a number of interesting questions can be investigated. The antineutrino cross-section can be studied at low energies for which there is limited current data. The detectors' charge separation capabilities can be used to place a limit on neutrino to antineutrino transitions for which the intrinsic flux is a principal background. However, these antineutrino studies present significant challenges because the horns defocus most of the antineutrino parents. This means that for antineutrino measurements, the standard neutrino analysis techniques must be modified to take into account the limited momentum range of the parents and the interactions in the decay pipe and other material in the neighborhood of the target. There is also a possibility under examination to reverse the horn focusing so that the beam is primarily antineutrinos, allowing antineutrino oscillation and CPT violation to be studied. [Preview Abstract] |
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F1.00024: MiniBooNE Event Reconstruction and Particle Identification Haijun Yang The MiniBooNE experiment at Fermilab is designed to confirm or refute the evidence for $\nu_\mu \rightarrow \nu_e$ oscillation at $\Delta m^2 \sim 1 eV^2/c^4$ found by the LSND experiment. It is a crucial experiment which may imply new physics beyond the standard model if the LSND signal is confirmed. This talk focus on event reconstruction, event identification and their performance based on two techniques, log-likelihood and boosted decision trees. For MiniBooNE event reconstruction, position resolution is about 23 cm, direction resolution is about $6^o$, energy resolution is about 15\%, reconstructed $\pi^0$ mass resolution is about 20 $MeV/c^2$. For MiniBooNE particle identification after preselection cuts, the electron efficiency is about 80\% for background efficiency of 0.5\%. [Preview Abstract] |
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F1.00025: Study of the rare decays $B^0 \rightarrow D_{s}^{(*)+} (\pi^{-}/\rho^{-})$ and $B^0 \rightarrow D_{s}^{(*)-} K^{(*)+}$ at the BaBar experiment Aritoki Suzuki We report on our study of $B^0$ mesons decaying into the final states $D_{s}^{(*)+} (\pi^{-}/\rho^{-})$ and $D_{s}^{(*)-} K^{(*)+}$ using a sample of 384 million $\Upsilon(4S)\to B\bar{B}$ events. The events have been collected with the BaBar detector at the PEP-II asymmetric-energy $e^{+}e^{-}$ storage ring, located at the Stanford Linear Accelerator Center. We exclusively reconstruct the modes $B^0\rightarrow D_{s}^{(*)+}(\pi^{-}/\rho^{-}), B^0\rightarrow D_{s}^{(*)-}K^{(*)+},D_{s}^{*+} \rightarrow D_{s}^{+} \gamma,~ D_{s}^{+} \rightarrow \phi \pi^{+},\ \bar{K}^{*0} K^{+},$ and $\bar{K}^{0} K^{+}$,$\rho^-\rightarrow \pi^-\pi^0$,and $K^{*+} \rightarrow \bar{K}^{0} \pi^{+},\ K^{+}\pi^{0}$, and measure their branching fractions. These results help in determining the $CP$ asymmetry parameter $\sin(2\beta+\gamma)$ in the decays $B^0 \rightarrow D^{(*)+} (\pi^{-}/\rho^{-})$ and provide constraints on long-distance strong-interaction effects in rare $B$ decays. [Preview Abstract] |
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F1.00026: Study of Direct CP Violation in $B$ Meson Decay to Final States Containing Charmonium Guennadi Borisov, Kostyantyn Holubyev We study direct CP violation in $b\rightarrow c\bar{c}(s,d)$ transitions by searching for a charge asymmetry in the decay $B^\pm\rightarrow J/\psi h^\pm$ where $h^\pm$ is a $K^\pm$ or $\pi^\pm$ meson. The results presented are based on a large data set of $p\bar{p} $ collisions recorded by the D0 detector operating at the Fermilab Tevatron. [Preview Abstract] |
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F1.00027: Time-dependent Dalitz analysis of $B^0\to K^0\pi^+\pi^-$ Alejandro Perez We present preliminary results of a maximum-likelihood, time-dependent Dalitz-plot analysis of charmless hadronic $B^0$ decays to the $K^0\pi^+\pi^-$ final state, from data corresponding to an integrated on-resonance luminosity of approximately 350~fb$^{-1}$ recorded by the BaBar experiment at the SLAC PEP-II asymmetric-energy $B$ Factory from 1999 to 2006. We measure decay amplitudes and phases for the intermediate resonance states, and extract time-dependent $CP$ asymmetries for the $\rho^0 K^0$ and $f_0 K^0$ intermediate states, and direct $CP$ asymmetries for $K^{*+}\pi^-$. [Preview Abstract] |
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F1.00028: Electrostatic Simulations of the XENON-10 Dark Matter Detector Roman Gomez We describe electrostatic finite element simulations that characterize the electrical fields present in the dual-phase chamber at the operating voltages. These simulations were used to minimize field inhomogeneities in the liquid and gas phases of the detector. Among the effects to be minimized are the fluctuations in gas-phase scintillation related to the relative orientation of the mesh electrodes and charge loss in the liquid-phase. In the current detector configuration, charge loss occurs only in small regions of the sensitive volume, limited to either very low z-coordinates (0.9 mm above the cathode) or large radii (up to 2.2 mm from the edge). This radial loss decreases with increasing z-coordinate. A detailed discussion of the obtained results will be presented. [Preview Abstract] |
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F1.00029: A Neutron Multiplicity Meter for Deep Underground Muon-Induced High Energy Neutron Measurements Raul Hennings-Yeomans, Daniel Akerib The nature of dark matter is one of the most important outstanding issues in particle physics, cosmology and astrophysics. A leading hypothesis is that Weakly Interacting Massive Particles, or WIMPs, were produced in the early universe and make up the dark matter. WIMP searches must be performed underground to shield from cosmic rays, which produce secondary particles that could fake a WIMP signal. Nuclear recoils from fast neutrons in underground laboratories are one of the most challenging backgrounds to WIMP detection. We present, for the first time, the design of an instrument capable of measuring the high energy ($>$60\,MeV) muon-induced neutron flux deep underground. The instrument is based on applying the Gd-loaded liquid-scintillator technique to measure the rate of multiple low energy neutron events produced in a Pb target and from this measurement to infer the rate of high energy neutron events. This unique signature allows both for efficient tagging of neutron multiplicity events as well as rejection of random gamma backgrounds so effectively that typical low-background techniques are not required. We will also discuss the benefits of using a neutron multiplicity meter as a component of active shielding. [Preview Abstract] |
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F1.00030: Detector Upgrade Studies on CMS Endcap Hadronic Calorimeter for SuperLHC Firdevs Duru The Large Hadron Collider (LHC) is designed to provide a beam energy of 7 TeV which corresponds to a luminosity of 10$^{34}$ cm$^{-2}$s$^{-1}$. The future LHC upgrade scenarios include increasing the luminosity to 10$^{35}$ cm$^{-2}$s$^{-1}$. We refer to this upgraded LHC as the SuperLHC (SLHC). The possible increase in luminosity requires some upgrades on the CMS detector as well. In this report we report the latest results from the ongoing R{\&}D studies to upgrade the CMS Endcap Hadronic Calorimeter, by replacing the scintillator tiles with quartz, for the very high radiation SLHC conditions. [Preview Abstract] |
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F1.00031: Measurement of Dirt Events with MiniBooNE Haijun Yang Dirt events from secondary particles(especially high energy gammas) produced from neutrino interactions in the matter surrounding the MiniBooNE detector has significant impact on the neutrino oscillation sensitivity. A direct measurement of dirt events is made by enriching the sample of dirt events using three variables (visible energy, distance from track center to tank wall along the backward track direction, angle between track direction and direction from tank center to track center). Based on 1-d, 2-d, 3-d histograms and using both $\chi^2$ and maximum-log-likelihood fit techniques, the fitted dirt rate defined as fitted dirt events divided by expected dirt events is $0.99 \pm 0.15$. [Preview Abstract] |
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F1.00032: Photon Mass, Graviton Mass: Zero or Not? Alfred Scharff Goldhaber, Michael Martin Nieto Testing for deviations from simple laws is a time-honored part of physics research. In electricity and magnetism the first approach to such testing, from the eighteenth century well into the twentieth, was to look for departures from -2 of the power of distance between two electric charges or two magnetic poles determining the force between them. Absent a particular length scale, this was a natural choice for parameterizing possible deviations from the simple and esthetic inverse square law. With the advent of relativity and quantum mechanics, and the realization that certain phenomena of light can be described in terms of photon particles, it became appealing to ask if these particles might have a non-zero mass, and Proca found the appropriate modification of the Maxwell equations. Despite the particle-motion origin of this idea, the most powerful way to constrain the size of a possible photon mass is by setting a lower bound on the Compton wavelength, by looking at static electric and especially magnetic fields over increasing length scales. For gravity similar statements apply, but graviton mass is theoretically questionable, and observed phenomena imply either additional sources or departures from Einstein's general relativity. [Preview Abstract] |
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F1.00033: First Measurement of the $W$ Boson Mass with CDF in Run II Bodhitha Jayatilaka, Christopher Hays, Ashutosh Kotwal, Larry Nodulman, Oliver Stelzer-Chilton, William Trischuk, Ian Vollrath We describe a measurement of the $W$ boson mass $m_W$ using $\approx$200 pb$^{-1}$ of $\sqrt{s}$=1.96 TeV $p\bar{p}$ collision data from the Fermilab Tevatron collected with the CDF II detector. Using 63,964 $W\rightarrow e\nu$ candidates and 51,128 $W\rightarrow \mu\nu$ candidates, we measure $m_W = 80.413 \pm 0.034~{\rm (stat)} \pm 0.034~{\rm (sys)}$ GeV/$c^2$. With a total uncertainty of 0.048 GeV/$c^2$, this is the single most precise $m_W$ measurement to date. [Preview Abstract] |
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F1.00034: QEDxQCD Resummation and Shower/ME Matching at the LHC Scott A. Yost, B.F.L. Ward We present the theory of QED$\otimes$QCD resummation and show how it allows shower/ME matching to arbitrary orders in perturbation theory. The theory is illustrated in applications to single heavy gauge boson production at the LHC. [Preview Abstract] |
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F1.00035: Recent $\Omega _{c}^{0}$ and $\Xi _{c}^{+}$ Analysis Results from SELEX Experiment Ugur Akgun We report the latest results from singly charmed baryon analyses done on hadro-production data taken by SELEX (E781) experiment. Fermilab charged hyperon beam ($\Sigma ^{-}$, $\pi ^{-}$, and p) at 600 GeV is used to produce charm particles in Cu and diamond targets. The latest results from lifetime and branching ratio analyses done with a sample of 107 $\Omega _{c}^{0}$ events will be presented as well as the lifetime analysis done on $\Xi _{c}^{+}$ for a sample of 301 events. [Preview Abstract] |
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F1.00036: ABSTRACT WITHDRAWN |
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F1.00037: Object Oriented Design and the Standard Model of particle physics Samir Lipovaca Inspired by the computer as both tool and metaphor, a new path emerges toward understanding life, physics, and existence. The path leads throughout all of nature, from the interior of cells to inside black holes. This view of science is based on the idea that information is the ultimate ``substance'' from which all things are made. Exploring this view, we will focus on Object - Oriented (OO) design as one of the most important designs in software development. The OO design views the world as composed of objects with well defined properties. The dynamics is pictured as interactions among objects. Interactions are mediated by messages that objects exchange with each other. This description closely resembles the view of the elementary particles world created by the Standard Model of particle physics. The object model (OM) provides a theoretical foundation upon which the OO design is built. The OM is based on the principles of abstraction, encapsulation, modularity and hierarchy. We will show that the Standard Model of particle physics follows the OM principles. [Preview Abstract] |
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F1.00038: Stability of renormalization group trajectories and the fermion flavor problem Ervin Goldfain An outstanding puzzle of the current standard model for particle physics (SM) is that both leptons and quarks arise in replicated patterns. Our work suggests that the number of fermion flavors occurring in the SM may be directly derived from the dynamics of renormalization group equations. The starting point is the system describing the coupling flow in the gauge sector \[ \frac{dg_i }{dt}\buildrel\textstyle.\over= \beta _i (g_i )=b_i (N,n_f )g_i^3 +O(g_i^5 ) \] where $i=(1,2,3)$ labels the gauge group of dimension $N$, $n_f $ is the number of fermion flavors and $t$ the sliding scale. With the help of the Routh-Hurwitz criterion, we find that the SM solution $n_f =6$ follows from demanding stability of the linearized flow about its fixed points. [Preview Abstract] |
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F1.00039: Uncertainties in Direct Dark Matter Detection Rates due to Nuclear Form Factors George Reifenberger, Gintaras Duda Theoretical calculations of neutralino cross sections with various nuclei are of great interest to direct dark matter searches such as CDMS, EDELWEISS, ZEPLIN, and other experiments. These cross sections and direct detection rates are generally computed with standard, one or two parameter model-dependent nuclear form factors, which may not exactly mirror the actual form factor for the particular nucleus in question. As is well known, elastic electron scattering can allow for very precise determinations of nuclear form factors and hence nuclear charge densities for spherical or near-spherical nuclei. We use charge densities derived from elastic electron scattering data to calculate model independent form factors for various target nuclei important in dark matter searches, such as Si, Ge, S, Ca and others. We have found that for nuclear recoils in the range of 1-100 keV significant differences in cross sections and rates exist when the model independent form factors are used. We will present quantitative uncertainties in detection rates due to nuclear form factors for current and proposed experiments in their relevant data-taking energy ranges. [Preview Abstract] |
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F1.00040: Beam Condition Monitoring with Diamonds at CDF Peter Dong, Ricardo Eusebi, Charlie Schrupp, Anna Sfyrla, Rick Tesarek, Rainer Wallny Particle physics collider experiments at the high energy frontier are being performed today and in the next decade in increasingly harsh radiation environments. While designing detector systems adequate for these conditions represents a challenge in itself, their safe operation relies heavily on fast, radiation-hard beam condition monitoring (BCM) systems to protect these expensive devices from beam accidents. The talk will present such a BCM system based on polycrystalline chemical vapor deposition (pCVD) diamond sensors designed for the Collider Detector at Fermilab (CDF) experiment operating at Fermilab's Tevatron proton-antiproton synchrotron. We report our operational experience with this system, which was commissioned in the spring of last year. The system currently represents the largest of its kind to be operated at a hadron collider. It is similar to designs being pursued by the next generation of hadron collider experiments at the Large Hadron Collider (LHC). [Preview Abstract] |
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F1.00041: UNDERGRADUATE RESEARCH |
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F1.00042: Interpretation of Midlatitude Observations of Total Electron Content Graham Ostrander, Michael Bartels, Hugh Gallagher In October 2004, a Coherent Ionospheric Doppler Receiver (CIDR) was installed at SUNY Oneonta. The CIDR measures Doppler shifts on 150 MHz and 400 MHz signals from beacons on a series of low earth orbiting satellites as these signals transect the ionosphere. The integrated number of electrons between the satellite and the receiver (known as the total electron content, TEC) is derived from the difference in the Doppler shifts of the 150 MHz and 400 MHz signals. Observations of TEC as a function of satellite elevation angle are fit to a model of the ionosphere to infer the ionospheric electron density. In order to assess the efficacy of this technique, our results are compared to observations from the array of North American GPS receivers. The technique is then used to examine the dependence of properties of the midlatitude density trough on magnetic activity. [Preview Abstract] |
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F1.00043: Asymmetric ring currents during the recovery phase of magnetic storms Jessica Edwards, Ismael Diaz, Ramon Lopez In this study we are comparing magnetic storms in which there is a fast shut off of energy from the solar wind versus storms in which the solar wind energy is slowly shut off. We are testing the hypothesis by O'Brien et al (2002) that slow shut off storms have assymetric ring currents during the recovery phase, whereas fast shut off storms will have symmetric ring currents during the recovery phase. If there is a symmetric ring current then there will be a symmetric disturbance and the Dst as measured from mid-lattitude stations should be similar in all features including the recovery phase. If there is an asymmetric ring current then the Dst profiles will look different and there will be delays in the recovery phases of those stations that see the ring current. We detrended the raw data from mid-latitude stations, calculated the disturbance at each station and looked for local time assymetry in these disturbances. Our preliminary results agree with the hypothesis set forth by O'Brien et al (2002) and we do see an asymmetry in the recovery phase of slow shut off storms. [Preview Abstract] |
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F1.00044: Field Line Currents in the Polar Cap Kelly Hallman, Jason Seiler, Salvador Hernandez, Jorge Landivar, Ramon Lopez Using satellite data, we have been searching for evidence of field aligned current flow on open magnetic field lines (Earth field lines that are connected to the solar wind). We collect magnotometer data from the DMSP F13 satellite, which flys at low altitudes over the polar cap. We identify the polar cap boundaries from precipitating particle data. The magnotometer data allows us to determine where field aligned currents flow. We believe we have found several cases of current flow on open field lines when the solar wind electric field is large. We will discuss the implications of these observations. [Preview Abstract] |
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F1.00045: Saturation of the polar cap flux Jason Seiler, Kelly Hallman, Salvador Hernandez, Jorge Landivar, Ramon Lopez We are using Interplanetary Magnetic Field (IMF) data to investigate the correlation exists between the magnitude of the Y component of the solar wind electric field and the latitude of the Earth's polar cap boundary. The location of that boundary is an indicator of how much magnetic flux is connected to the IMF. It is well known that there is a correlation between the polar cap boundary and the solar wind Ey for moderate values of Ey. We are investigating if that correlation disappears during very large Ey, that is to say, we are investigating if the polar cap flux saturates for a given value of Ey. [Preview Abstract] |
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F1.00046: CISM{\_}DX OpenDX Tutorials with Self-Contained Instructions Stacy Irwin, Salvador Hernandez, Jorge Landivar, Ramon Lopez OpenDX is one program in the CISM{\_}DX software package that uses a Visual Program Editor (VPE) to create programs to visualize simulation data as part of the Center for Integrated Space Weather Modelling (CISM). We have developed two tutorials using OpenDX to teach beginning students to create visualizations. These tutorials assume a basic understanding of how to select, place, connect and configure VPE modules as well as basic navigation within OpenDX. Tutorial 1 teaches a user how to create a basic animation without external inputs. Tutorial 2 introduces data importation and visualization on a cut scalar plane. The advantage of these tutorials is the user's immediate involvement in creating programs without an external instruction manual. Both tutorials are designed specifically to introduce the Florida Tech CISM group's new members to the basics of OpenDX. [Preview Abstract] |
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F1.00047: Disposable electrolytic hydraulic microfluidic pump (EHMFP) for point-of-care pathogenic detection system Alhaji Cherif, Scott Stelick, Nathaniel C. Cady, Carl A. Batt We report an electrolytic hydraulic pump consisting of electrolytic, hydraulic and fluidic chambers. We present a novel prototype and optimized microfluidic pumps that separate the hydraulic fluid from the carrier fluid and are capable of producing high pressure (7-16psi) with low power consumption (10-72mW), low current (2-11mA) and voltage requirements (5-12V). A lithographically fabricated poly(dimenthylsiloxane) pump was created which can be easily integrated into $\mu $-TAS devices. We examined the pumps fabricated with 1:1 and 1:2 fluidic-hydraulic chamber ratio, and observed a consistent flow rate versus voltage. For the range of 5-12V, flow rates of 8-27$\mu $l/min and 7-30$\mu $l/min were measured for 1:1 and 1:2 designs (max. volume of 150-300$\mu $l). Optimum results were obtained for 1:1 design for both prototype and optimized devices under the application of 9V with rates of 17$\mu $l/min and 21$\mu $l/min, respectively. The flow rate of the optimized 1:1 design is within that of $\sim $23$\mu $l/min (SD 3.85) of the prototype 1:2 design. Armed with the improved device design, the effect of concentration of the electrolyte, rate of electrolysis, and electrode choice on the flow rate of the pumping fluid can be explored. [Preview Abstract] |
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F1.00048: Setting limits on a new parameter outside of Standard Model muon decay. Kristen Williams This work is a response to predictions concerning a new tensor interaction which is outside of the Michel local interactions of Standard Model muon decay. This interaction is assumed to be parameterized by the addition of a new variable, $\kappa $, to the differential decay probability spectrum. The \textit{TWIST} experiment is measuring the Michel parameters $\rho $, $P_{\mu }\xi $, and $\delta $ in muon decay to search for deviations from the Standard Model. Our analysis was of the approximate contribution that $\kappa $ would make to the \textit{TWIST} measurements and the sensitivity of this contribution to the fitted momentum range. Efforts were made to set a limit on $\kappa $ in accordance with both past \textit{TWIST} fit ranges and assumed future ones. [Preview Abstract] |
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F1.00049: In-beam gamma-ray spectroscopy of 172Os K. Aleksandrova, P. Manchev, M.S. Fetea, A. Heinz, G. Gurdal, R. Casperson, R.F. Casten, M. Chamberlain, E.A. McCutchan, J. Qian, N.J. Thompson, V. Werner, R. Winkler A 30Si beam was used for a test experiment at the WNSL facility. The production of the compound nucleus 174Os was achieved through complete fusion in a 100 ug/cm2 144Sm target at beam energy of 134MeV. Gamma-rays from residual nuclei were detected with the YRAST ball array consisting of 7 Compton-suppressed clover detectors. A number of Os isotopes, in particular 172Os were also detected. While the main goal of the experiment was the commissioning of a gas-filled detector, we present here data from in-beam gamma-ray spectroscopy. [Preview Abstract] |
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F1.00050: Describing Nuclei on the Alhassid-Whelan Arc of Regularity in a SU(3) Basis P. Manchev, M.S. Fetea, R.F. Casten, S. Eckel Until fairly recently, it was thought that most nuclei lie on or near the perimeter of the Casten triangle. It is now known this is not the case; in fact, most nuclei inhabit the interior of the Casten triangle. More than a decade ago Alhassid and Whelan discovered a striking benchmark. They identified an interior path connecting the U(5) and SU(3) vertices of the Casten triangle which unlike most of the rest of the interior does not exhibit chaos but rather preserves regularity. Jolie et al. [1] found 12 nuclei whose parameters lie along this regularity. They also identified an almost one-to-one correspondence between the near degeneracy of the gamma band head and the K=0 2+ band head for those nuclei. Most of the calculations involving the IBA are done in a U(5) basis. Wave functions of the nuclei on the arc of regularity are complicated when expressed in a U(5) basis but may be easier to work with in a SU(3) basis. Our goal is to determine features of nuclei on or close to the Arc based on the SU(3) description of their wave functions. Preliminary results will be presented. References: [1] J. Jolie et al., Phys. Rev. Lett. 93, 132501 (2004). [Preview Abstract] |
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