Physical Sciences and Mathematics Commons^™

Pseudorapidity Distribution Of Charged Hadrons In Proton-Proton Collisions At Root S=13tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The pseudorapidity distribution of charged hadrons in pp collisions at √s=13TeVis measured using a data sample obtained with the CMS detector, operated at zero magnetic field, at the CERN LHC. The yield of primary charged long-lived hadrons produced in inelastic pp collisions is determined in the central region of the CMS pixel detector (|η| <2) using both hit pairs and reconstructed tracks. For central pseudorapidities (|η| <0.5), the charged-hadron multiplicity density is dNch/dη||η|<0.5=5.49 ±0.01 (stat)±0.17 (syst), a value obtained by combining the two methods. The result is compared to predictions from Monte Carlo event generators and to similar measurements made at lower collision energies.

Solvothermal Synthesis, Structure And Optical Property Of Nanosized Cosb3 Skutterudite, Latha Kumari, Wenzhi Li, Jianyu Huang, Paula P. Provencio

Department of Physics

Binary skutterudite CoSb₃ nanoparticles were synthesized by solvothermal method. The nanostructuring of CoSb₃ material was achieved by the inclusion of various kinds of additives. X-ray diffraction examination indicated the formation of the cubic phase of CoSb₃. Structural analysis by transmission electron microscopy analysis further confirmed the formation of crystalline CoSb₃ nanoparticles with high purity. With the assistance of additives, CoSb₃ nanoparticles with size as small as 10 nm were obtained. The effect of the nanostructure of CoSb₃ on the UV–visible absorption and luminescence was studied. The nanosized CoSb₃ skutterudite may find application …

Preface To Special Topic: Amyloid Aggregation: Characterization, Function And Molecular Mechanisms, Bernard S. Gerstman, Yifat Miller

Department of Physics

No abstract provided.

Search For Diphoton Resonances In The Mass Range From 150 To 850gev In Pp Collisions At √S=8 Tev, Cms Collaboration, Cern Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Results are presented of a search for heavy particles decaying into two photons. The analysis is based on a 19.7 fb−1sample of proton–proton collisions at √s=8 TeVcollected with the CMS detector at the CERN LHC. The diphoton mass spectrum from 150 to 850GeVis used to search for an excess of events over the background. The search is extended to new resonances with natural widths of up to 10% of the mass value. No evidence for new particle production is observed and limits at 95% confidence level on the production cross section times branching fraction to diphotons are determined. These limits …

Study Of W Boson Production In Ppb Collisions At √Snn=5.02tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The first study of W boson production in pPb collisions is presented, for bosons decaying to a muon or electron, and a neutrino. The measurements are based on a data sample corresponding to an integrated luminosity of 34.6nb−1at a nucleon–nucleon centre-of-mass energy of √sNN=5.02TeV, collected by the CMS experiment. The W boson differential cross sections, lepton charge asymmetry, and forward–backward asymmetries are measured for leptons of transverse momentum exceeding 25GeV/c, and as a function of the lepton pseudorapidity in the |ηlab| <2.4range. Deviations from the expectations based on currently available parton distribution functions are observed, showing the need for including W boson data in nuclear parton distribution global fits.

Assessing Student Reasoning In Upper-Division Electricity And Magnetism At Oregon State University, Justyna P. Zwolak, Corinne A. Manogue

Stem Transformation Institute

[This paper is part of the Focused Collection on Upper Division Physics Courses.] Standardized assessment tests that allow researchers to compare the performance of students under various curricula are highly desirable. There are several research-based conceptual tests that serve as instruments to assess and identify students’ difficulties in lower-division courses. At the upper-division level assessing students’ difficulties is a more challenging task. Although several research groups are currently working on such tests, their reliability and validity are still under investigation. We analyze the results of the Colorado Upper-Division Electrostatics diagnostic from Oregon State University and compare it with data from …

Angular Coefficients Of Z Bosons Produced In Pp Collisions At √S=8tevand Decaying To Μ+Μ−As A Function Of Transverse Momentum And Rapidity, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Measurements of the five most significant angular coefficients, A0through A4, for Z bosons produced in pp collisions at √s=8TeVand decaying to μ+μ−are presented as a function of the transverse momentum and rapidity of the Z boson. The integrated luminosity of the dataset collected with the CMS detector at the LHC corresponds to 19.7 fb−1. These measurements provide comprehensive information about the Z boson production mechanisms, and are compared to the QCD predictions at leading order, next-to-leading order, and next-to-next-to-leading order in perturbation theory.

First Measurement Of The Polarization Observable E In The P→(Γ→,Π+)N Reaction Up To 2.25 Gev, Clas Collaboration, R.A. Badui, Lei Guo

Department of Physics

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction γ p→π+n, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-Lmultipoles contribute. The data have been included in new multipole analyses …

Search For Resonant Pair Production Of Higgs Bosons Decaying To Two Bottom Quark–Antiquark Pairs In Proton–Proton Collisions At 8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A model-independent search for a narrow resonance produced in proton–proton collisions at √s=8TeVand decaying to a pair of 125GeV Higgs bosons that in turn each decays into a bottom quark–antiquark pair is performed by the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 17.9fb−1. No evidence for a signal is observed. Upper limits at a 95% confidence level on the production cross section for such a resonance, in the mass range from 270 to 1100GeV, are reported. Using these results, a radion with decay constant of 1TeV and mass from 300 to 1100GeV, and …

Measurement Of The Z Boson Differential Cross Section In Transverse Momentum And Rapidity In Proton–Proton Collisions At 8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

We present a measurement of the Z boson differential cross section in rapidity and transverse momentum using a data sample of pp collision events at a centre-of-mass energy √s=8TeV, corresponding to an integrated luminosity of 19.7fb−1. The Z boson is identified via its decay to a pair of muons. The measurement provides a precision test of quantum chromodynamics over a large region of phase space. In addition, due to the small experimental uncertainties in the measurement the data has the potential to constrain the gluon parton distribution function in the kinematic regime important for Higgs boson production via gluon fusion. …

Search For Lepton-Flavour-Violating Decays Of The Higgs Boson, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The first direct search for lepton-flavour-violating decays of the recently discovered Higgs boson (H) is described. The search is performed in the H →μτeand H →μτhchannels, where τeand τhare tau leptons reconstructed in the electronic and hadronic decay channels, respectively. The data sample used in this search was collected in pp collisions at a centre-of-mass energy of √s=8TeVwith the CMS experiment at the CERN LHC and corresponds to an integrated luminosity of 19.7fb−1. The sensitivity of the search is an order of magnitude better than the existing indirect limits. A slight excess of signal events with a significance of 2.4 …

Measurements Of The ϒ(1s), ϒ(2s), And ϒ(3s)Differential Cross Sections In Pp Collisions At √S=7 Tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Differential cross sections as a function of transverse momentum pTare presented for the production of ϒ(nS)(n=1, 2, 3) states decaying into a pair of muons. Data corresponding to an integrated luminosity of 4.9fb−1in pp collisions at √s=7 TeVwere collected with the CMS detector at the LHC. The analysis selects events with dimuon rapidity |y| <1.2and dimuon transverse momentum in the range 10

Search For Narrow High-Mass Resonances In Proton–Proton Collisions At √S=8tevdecaying To A Z And A Higgs Boson, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A search for a narrow, high-mass resonance decaying into Z and Higgs (H) bosons is presented. The final state studied consists of a merged jet pair and a τpair resulting from the decays of Z and Hbosons, respectively. The analysis is based on a data sample of proton–proton collisions at a center-of-mass energy of 8TeV, collected with the CMS experiment in 2012, and corresponding to an integrated luminosity of 19.7fb−1. In the resonance mass range of interest, which extends from 0.8 to 2.5TeV, the Z and H bosons are produced with large momenta, which implies that the final products of …

Search For A Pseudoscalar Boson Decaying Into A Z Boson And The 125 Gev Higgs Boson In View The Mathml Sourceℓ+ℓ−Bb‾ Final States, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Results are reported on a search for decays of a pseudoscalar A boson into a Z boson and a light scalar h boson, where the Z boson decays into a pair of oppositely-charged electrons or muons, and the h boson decays into bb. The search is based on data from proton–proton collisions at a center-of-mass energy √s=8TeVcollected with the CMS detector, corresponding to an integrated luminosity of 19.7fb−1. The h boson is assumed to be the standard model-like Higgs boson with a mass of 125GeV. With no evidence for signal, upper limits are obtained on the product of the production …

Search For Heavy Majorana Neutrinos In Μ±Μ±+Jets Events Inproton–Proton Collisions At√S=8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A search is performed for heavy Majorana neutrinos (N) using an event signature defined by two muons of the same charge and two jets (μ±μ±jj). The data correspond to an integrated luminosity of 19.7fb−1of proton–proton collisions at a center-of-mass energy of 8TeV, collected with the CMS detector at the CERN LHC. No excess of events is observed beyond the expected standard model background and upper limits are set on |VμN|2as a function of Majorana neutrino mass mNfor masses in the range of 40–500GeV, where VμNis the mixing element of the heavy neutrino with the standard model muon neutrino. The limits …

Macular Pigment And Lens Optical Density Measurements-Evaluating A Flicker Machine With Novel Features, Anirbaan Mukherjee

FIU Electronic Theses and Dissertations

Age related macular degeneration (AMD) is one of the leading causes of blindness amongst the elderly. Macular pigment (MP) in the retina has been established to protect individuals against AMD. Improving levels of MP by diet or supplements is the constant quest of clinical practitioners and researchers, thus necessitating development of instruments capable of repeatable and reliable MP measurement. Cataract, a consequence of the rising opacity levels of the lens with age is one of the other major causes of blindness in the world. Mapcatsf, a LED-based microprocessor-controlled heterochromatic flicker photometer (HFP) using photopic vision is capable of measuring the …

A Charged Fusion Product Diagnostic For A Spherical Tokamak, Ramona V. Perez

FIU Electronic Theses and Dissertations

Designs for future nuclear fusion power reactors rely on the ability to create a stable plasma (hot ionized gas of hydrogen isotopes) as a medium with which to sustain nuclear fusion reactions. My dissertation work involves designing, constructing, testing, installing, operating, and validating a new diagnostic for spherical tokamaks, a type of reactor test facility. Through detecting charged particles emitted from the plasma, this instrument can be used to study fusion reaction rates within the plasma and how they are affected by plasma perturbations. Quantitatively assessing nuclear fusion reaction rates at specific locations inside the plasma and as a function …

Self-Assembly Dynamics For The Transition Of A Globular Aggregate To A Fibril Network Of Lysozyme Proteins Via A Coarse-Grained Monte Carlo Simulation, R. B. Pandey, B. L. Farmer, Bernard S. Gerstman

Department of Physics

The self-organizing dynamics of lysozymes (an amyloid protein with 148 residues) with different numbers of protein chains, Nc = 1,5,10, and 15 (concentration 0.004 – 0.063) is studied by a coarse-grained Monte Carlo simulation with knowledge-based residue-residue interactions. The dynamics of an isolated lysozyme (Nc = 1) is ultra-slow (quasi-static) at low temperatures and becomes diffusive asymptotically on raising the temperature. In contrast, the presence of interacting proteins leads to concentration induced protein diffusion at low temperatures and concentration-tempering sub-diffusion at high temperatures. Variation of the radius of gyration of the protein with temperature shows a systematic transition from a …

Measurement Of The Cross Section Ratio Σttbb/Σttjjin Ppcollisions At√S=8tev, Cms Collaboration, Cern Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The first measurement of the cross section ratio σttbb/σttjjis presented using a data sample corresponding to an integrated luminosity of 19.6fb−1collected in pp collisions at √s=8TeVwith the CMS detector at the LHC. Events with two leptons (eor μ) and four reconstructed jets, including two identified as b quark jets, in the final state are selected. The ratio is determined for a minimum jet transverse momentum pTof both 20 and 40GeV/c. The measured ratio is 0.022 ±0.003 (stat) ±0.005 (syst)for pT>20GeV/c. The absolute cross sections σttbband σttjjare also measured. The measured ratio for pT>40GeV/cis compatible with a theoretical quantum …

Search For Quark Contact Interactions And Extra Spatial Dimensions Using Dijet Angular Distributions In Proton–Proton Collisions At √S=8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A search is presented for quark contact interactions and extra spatial dimensions in proton–proton collisions at √s=8TeVusing dijet angular distributions. The search is based on a data set corresponding to an integrated luminosity of 19.7fb−1collected by the CMS detector at the CERN LHC. Dijet angular distributions are found to be in agreement with the perturbative QCD predictions that include electroweak corrections. Limits on the contact interaction scale from a variety of models at next-to-leading order in QCD corrections are obtained. A benchmark model in which only left-handed quarks participate is excluded up to a scale of 9.0 (11.7)TeV for destructive …

Search For Pair-Produced Resonances Decaying To Jet Pairs In Proton–Proton Collisions At √S=8tev, Cms Collaboration, Cern Switzerland, Samantha Hewamanage, Stephan Linn, Pete Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Results are reported of a general search for pair production of heavy resonances decaying to pairs of hadronic jets in events with at least four jets. The study is based on up to 19.4fb−1of integrated luminosity from proton–proton collisions at a center-of-mass energy of 8TeV, recorded with the CMS detector at the LHC. Limits are determined on the production of scalar top quarks (top squarks) in the framework of R-parity violating supersymmetry and on the production of color-octet vector bosons (colorons). First limits at the LHC are placed on top squark production for two scenarios. The first assumes decay to …

Search For A Standard Model-Like Higgs Boson In The Μ+Μ−And E+E−Decay Channels At The Lhc, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A search is presented for a standard model-like Higgs boson decaying to the μ+μ−or e+e−final states based on proton–proton collisions recorded by the CMS experiment at the CERN LHC. The data correspond to integrated luminosities of 5.0fb−1at a centre-of-mass energy of 7TeV and 19.7fb−1at 8TeV for the μ+μ−search, and of 19.7fb−1at 8TeV for the e+e−search. Upper limits on the production cross section times branching fraction at the 95% confidence level are reported for Higgs boson masses in the range from 120 to 150GeV. For a Higgs boson with a mass of 125GeV decaying to μ+μ−, the observed (expected) upper limit …

Present-Day Pattern Variations In The Central And Eastern Pacific El Nino, Szandra Peter

Undergraduate Research at FIU (URFIU) Conference

El Niño and the Southern Oscillation (ENSO) is a cycle that is initiated in the equatorial Pacific Ocean and is recognized on interannual timescales by oscillating patterns in tropical Pacific sea surface temperatures (SST) and atmospheric circulations. Using correlation and regression analysis of datasets that include SST’s and other interdependent variables including precipitation, surface winds, sea level pressure, this research seeks to quantify recent changes in ENSO behavior. Specifically, the amplitude, frequency of occurrence, and spatial characteristics (i.e. events with maximum amplitude in the Central Pacific versus the Eastern Pacific) are investigated.

The research is based on the question; “Are …

Search For Stealth Supersymmetry In Events With Jets, Either Photons Or Leptons, And Low Missing Transverse Momentum In Pp Collisions At 8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

The results of a search for new physics in final states with jets, either photons or leptons, and low missing transverse momentum are reported. The study is based on a sample of proton–proton collisions collected at a center-of-mass energy √s=8TeVwith the CMS detector in 2012. The integrated luminosity of the sample is 19.7fb−1. Many models of new physics predict the production of events with jets, electroweak gauge bosons, and little or no missing transverse momentum. Examples include stealth models of supersymmetry (SUSY), which predict a hidden sector at the electroweak energy scale in which SUSY is approximately conserved. The data …

Functional Connectivity Modeling Of Consistent Cortico-Striatal Degeneration In Huntington3s Disease, Imis Dogan, Claudia R. Eickhoff, Peter T. Fox, Angela Laird, Jörg B. Schulz, Simon B. Eickhoff, Kathrin Reetz

Department of Physics

Huntington3s disease (HD) is a progressive neurodegenerative disorder characterized by a complex neuropsychiatric phenotype. In a recent meta-analysis we identified core regions of consistent neurodegeneration in premanifest HD in the striatum and middle occipital gyrus (MOG). For early manifest HD convergent evidence of atrophy was most prominent in the striatum, motor cortex (M1) and inferior frontal junction (IFJ). The aim of the present study was to functionally characterize this topography of brain atrophy and to investigate differential connectivity patterns formed by consistent cortico-striatal atrophy regions in HD. Using areas of striatal and cortical atrophy at different disease stages as seeds, …

Multimode Analysis Of Nanoscale Biomolecular Interactions, Purushottam Babu Tiwari

FIU Electronic Theses and Dissertations

Biomolecular interactions, including protein-protein, protein-DNA, and protein-ligand interactions, are of special importance in all biological systems. These interactions may occer during the loading of biomolecules to interfaces, the translocation of biomolecules through transmembrane protein pores, and the movement of biomolecules in a crowded intracellular environment. The molecular interaction of a protein with its binding partners is crucial in fundamental biological processes such as electron transfer, intracellular signal transmission and regulation, neuroprotective mechanisms, and regulation of DNA topology. In this dissertation, a customized surface plasmon resonance (SPR) has been optimized and new theoretical and label free experimental methods with related analytical …

Measurement Of The Production Cross Section Ratio Σ(Χb2(1p))/Σ(Χb1(1p))In Pp Collisions At √S=8tev, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

A measurement of the production cross section ratio σ(χb2(1P))/σ(χb1(1P))is presented. The χb1(1P)and χb2(1P)bottomonium states, promptly produced in pp collisions at √s=8TeV, are detected by the CMS experiment at the CERN LHC through their radiative decays χb1,2(1P) →ϒ(1S) +γ. The emitted photons are measured through their conversion to e+e−pairs, whose reconstruction allows the two states to be resolved. The ϒ(1S)is measured through its decay to two muons. An event sample corresponding to an integrated luminosity of 20.7fb−1is used to measure the cross section ratio in a phase-space region defined by the photon pseudorapidity, |ηγ| <1.0; the ϒ(1S)rapidity, |yϒ| <1.5; and the ϒ(1S)transverse momentum, 7

Long-Range Two-Particle Correlations Of Strange Hadrons With Charged Particles In Ppb And Pbpb Collisions At Lhc Energies, Cms Collaboration, Cern, Switzerland, Samantha Hewamanage, Stephan Linn, Pete E. Markowitz, German Martinez, Jorge Luis Rodriguez

Department of Physics

Measurements of two-particle angular correlations between an identified strange hadron (K0Sor Λ/Λ) and a charged particle, emitted in pPb collisions, are presented over a wide range in pseudorapidity and full azimuth. The data, corresponding to an integrated luminosity of approximately 35nb−1, were collected at a nucleon–nucleon center-of-mass energy (√sNN) of 5.02TeV with the CMS detector at the LHC. The results are compared to semi-peripheral PbPb collision data at √sNN=2.76TeV, covering similar charged-particle multiplicities in the events. The observed azimuthal correlations at large relative pseudorapidity are used to extract the second-order (v2) and third-order (v3) anisotropy harmonics of K0Sand Λ/Λparticles. These …