Physical Sciences and Mathematics Commons^™

Study Of W Boson Production In Pbpb And Pp Collisions At √Snn = 2.76 Tev, Ekaterina Avdeeva, Kenneth A. Bloom, S. S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

A measurement is presented of W-boson production in PbPb collisions carried out at a nucleon–nucleon (NN) centre-of-mass energy √s_NN of 2.76 TeV at the LHC using the CMS detector. In data corresponding to an integrated luminosity of 7.3 μb⁻¹, the number of W → μν_μ decays is extracted in the region of muon pseudorapidity |η^μ| < 2.1 and transverse momentum p^μ_T > 25 GeV/c. Yields of muons found per unit of pseudorapidity correspond to (159 ± 10(stat.) ± 12(syst.)) × 10⁻⁸ W⁺ and (154 ± 10(stat.) ± 12(syst.)) × 10⁻⁸ W⁻ bosons per …

Search For Large Extra Dimensions In Dimuon And Dielectron Events In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

Results are presented from a search for large, extra spatial dimensions in events with either two isolated muons or two isolated electrons. The data are from proton–proton interactions at √s = 7 TeV collected with the CMS detector at the LHC. The size of the data sample corresponds to an integrated luminosity of approximately 2 fb⁻¹. The observed dimuon and dielectron mass spectra are found to be consistent with standard-model expectations. Depending on the number of extra dimensions, the 95% confidence level limits from the combined μμ and ee channels range from M_s > 2.4 TeV to …

Search For The Standard Model Higgs Boson Decaying Into Two Photons In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a center-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 fb⁻¹. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at …

Observation Of A New Boson At A Mass Of 125 Gev With The Cms Experiment At The Lhc, Cms Collaboration, Garhan Attebury, Ekaterina Avdeeva, Kenneth A. Bloom, Brian Bockelman, S. Bose, Daniel R. Claes, Aaron Dominguez, Michael Eads, J. Keller, Ilya Kravchenko, J. Lazo-Flores, Carl Lundstedt, H. Malbouisson, Sudhir Malik, Gregory Snow, David R. Swanson

Kenneth Bloom Publications

Results are presented from searches for the standard model Higgs boson in proton–proton collisions at √s = 7 and 8 TeV in the Compact Muon Solenoid experiment at the LHC, using data samples corresponding to integrated luminosities of up to 5.1 fb⁻¹ at 7 TeV and 5.3 fb⁻¹ at 8 TeV. The search is performed in five decay modes: γγ, ZZ, W⁺W⁻, τ⁺τ⁻, and bb̅. An excess of events is observed above the expected background, with a local significance of 5.0 standard deviations, at a mass near 125 …

Spin Pumping In Lateral Double Quantum Dot Systems, Sabine S. Pelton

Electronic Theses and Dissertations

Electron transport in single lateral quantum dot (QD) and parallel lateral double quantum dot (DQD) systems is modeled using semiclassical rate equations. The Zeeman effect, in conjunction with resonant tunneling, is used to select the spin of electrons involved in transport. We show adiabatic spin pumping by periodic variation of the systems' confining parameters, namely the quantum point contacts (QPCs) dictating the boundaries of the dots, and the gate voltage applied to each dot. The limitations of adiabatic spin pumping are subsequently examined by counting the average spin pumped per cycle when frequency and interdot capacitance are adjusted.

Structural, Magnetic, And Electron Transport Properties Of Mnbi:Fe Thin Films, Parashu Kharel, X. Z. Li, V. R. Shah, N. Al-Aqtash, K. Tarawneh, Renat F. Sabirianov, R. Skomski, D. J. Sellmyer

Physics Faculty Publications

The structural, magnetic, and electron transport properties ofMn55=xFexBi45 (x¼0, 2, 4, 5, 8, 11, 13, 16) films prepared by multilayer deposition and annealing using e-beam evaporation have been investigated. Fe doping has produced a significant change in the magnetic properties of the samples including the decrease in saturation magnetization and magnetocrystalline anisotropy and increase in coercivity. Although the magnetization shows a smooth decrease with increasing Fe concentration, the coercivity jumps abruptly from 8.5 kOe to 22 kOe as Fe content changes from 4% to 5%, but the change in coercivity is small as the concentration goes beyond 5%. The temperature …

Characterization Of Ceramic Matrix Composite Materials Using Millimeter-Wave Techniques, Matthew Lee Bischoff

Browse all Theses and Dissertations

This thesis describes studies that were carried out on Ceramic Matrix Composite (CMC) materials. These materials were provided by the Air Force Research Laboratory for evaluation in the millimeter-wave frequency region with the goal of developing Non-Destructive Evaluation techniques. This thesis centers on describing the measured reflections from an Oxide/Oxide and SiC/SiNC CMC materials. Models were derived from the Fresnel equations to account for the reflected and transmitted waves in these materials. System models were developed to describe the power coupling of the spectra measured in three separate measurement systems. Using these models the complex index of refraction was determined …

The Mechanisms Of Luminescence From Zno Under Electron Irradiation, Devin Marlinjames Todd

Browse all Theses and Dissertations

Zinc Oxide has been utilized for centuries in a wide range of applications including medical, food, and materials. It is now that ZnO draws much attention to its potential as a high frequency semiconductor and UV laser. As a result, there has been much investigation into the properties of ZnO and many papers have been published in the area. Despite this fact, there is still much that is unknown about its electronic defect structure. This research investigates the broad region of the Zinc Oxide luminescence spectrum known as the green band, which lies roughly between 480 - 580 nm or …

Inclusive And Differential Measurements Of The Tt̅ Charge Asymmetry In Proton–Proton Collisions At √S= 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, J. Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

The tt̅ charge asymmetry is measured in events containing a charged lepton (electron or muon) and at least four jets, one of which is identified as originating from b-quark hadronization. The analyzed data set corresponds to an integrated luminosity of 5.0 fb⁻¹ collected with the CMS detector at the LHC. An inclusive and three differential measurements of the tt̅ charge asymmetry as a function of rapidity, transverse momentum, and invariant mass of the tt̅ system are presented. The measured inclusive tt̅ charge asymmetry is A_C = 0.004 ± 0.010 (stat.) ± 0.011 (syst.). This result and the three …

Jet Momentum Dependence Of Jet Quenching In Pbpb Collisions At √Snn = 2.76 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, J. Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, Jose Lazo-Flores, Helena Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

Dijet production in PbPb collisions at a nucleon–nucleon center-of-mass energy of 2.76 TeV is studied with the CMS detector at the LHC. A data sample corresponding to an integrated luminosity of 150 μb⁻¹ is analyzed. Jets are reconstructed using combined information from tracking and calorimetry, using the anti-k_T algorithm with R = 0.3. The dijet momentum balance and angular correlations are studied as a function of collision centrality and leading jet transverse momentum. For the most peripheral PbPb collisions, good agreement of the dijet momentum balance distributions with pp data and reference calculations at the same collision …

An Investigation Of Air Resistance On Projectile Motion From Aristotle To Euler, Michael Edward Clayton

Theses Digitization Project

From antiquity until today, mathematicians have tried to develop a theory of projectile motion. The development of a theory of projectile motion began with just a basic observation of motion by the great Greek mathematician Aristotle and has evolved to become more than conjecture or hypothesis, but a well developed science of prediciting the flight and accuracy of a projectile in motion. This thesis traces the development of the theory of projectile motion from Greek antiquity to about the mid 1700's.

A First Course In Loop Quantum Gravity, Seth Major

Articles

No abstract provided.

Plane Gravitational Waves And Loop Quantization, F. Hinterleitner, Seth Major

Articles

Starting from the polarized Gowdy model in Ashtekar variables, the Killing equations characteristic for plane-fronted parallel gravitational waves are introduced in part as a set of first-class constraints, in addition to the standard ones of General Relativity. These constraints are expressed in terms of quantities that have an operator equivalent in Loop Quantum Gravity, making plane wave space-times accessible to loop quantization techniques.

Quantum Geometry Phenomenology: Angle And Semiclassical States, Seth Major

Articles

The phenomenology for the deep spatial geometry of loop quantum gravity is discussed. In the context of a simple model of an atom of space, it is shown how purely combinatorial structures can affect observations. The angle operator is used to develop a model of angular corrections to local, continuum flat-space 3-geometries. The physical effects involve neither breaking of local Lorentz invariance nor Planck scale suppression, but rather only involve the combinatorics of SU(2) recoupling. Bhabha scattering is discussed as an example of how the effects might be observationally accessible.

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopologues: 1. Comparison Between Models And Observations, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Debra Wunch, Vanessa Sherlock, Nicholas Deutscher, David Griffith, Paul O. Wennberg, Kimberly Strong, Dan Smale, Emmanuel Mahieu, Sabine Barthlott, Frank Hase, Omaira García, Justus Notholt, Thorsten Warneke, Geoffrey Toon, David Sayres, Sandrine Bony, Jeonghoon Lee, Derek Brown, Ryu Uemura, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

The goal of this study is to determine how H₂O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H₂O characteristics that are robust across data sets and that can be used to evaluate …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopic Observations: 2. Using Isotopic Diagnostics To Understand The Mid And Upper Tropospheric Moist Bias In The Tropics And Subtropics, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Sandrine Bony, Jeonghoon Lee, Derek Brown, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

Evaluating the representation of processes controlling tropical and subtropical tropospheric relative humidity (RH) in atmospheric general circulation models (GCMs) is crucial to assess the credibility of predicted climate changes. GCMs have long exhibited a moist bias in the tropical and subtropical mid and upper troposphere, which could be due to the mis-representation of cloud processes or of the large-scale circulation, or to excessive diffusion during water vapor transport. The goal of this study is to use observations of the water vapor isotopic ratio to understand the cause of this bias. We compare the three-dimensional distribution of the water vapor isotopic …

Spatial Ability And Achievement In High School Physics, Michael Shawn Liner

LSU Master's Theses

This study investigates the relationship between a student’s spatial abilities and their success in high school physics. First, I investigate whether the success of students in high school physics class correlates with their spatial abilities before taking the class. Second, I investigate whether taking high school physics has an effect on student’s spatial abilities. No direct intervention was given to any of the students. Three instruments were administered to determine the student’s spatial abilities, The Perspective Taking/Spatial Orientation Test (Hegarty & Waller, 2004), The Mental Rotation Test (Peters & Laeng, 1995), and The Paper Folding Test (Ekstrom, French, Harmon, & …

Advances In Quantum Optical Metrology And The Establishment Of An Invisible Quantum Tripwire, Steven Blane Mccracken

LSU Doctoral Dissertations

This thesis presents a summary of the foundation and background of the field of quantum optics, and an analysis of some recent discoveries in various fields of which I have aided in furthering investigative research and advancement through publications. Such topics include numerical optimization of generalized quantum states used in phase sensitive quantum metrology, an analysis of object detection through the use of quantum interferometry in the presence of lossy conditions, and the use of the latter technique to propose an invisible quantum tripwire. First is a collaborative effort to numerically optimize quantum optical states for quantum metrological applications. We …

Realization Of Random-Field Ising Ferromagnetism In A Molecular Magnet, Bo Wen, P Subedi, Lin Bo, Y Yeshurun, M P. Sarachik, A D. Kent, A J. Millis, Christos Lampropoulos, G Christou

Christos Lampropoulos

The longitudinal magnetic susceptibility of single crystals of the molecular magnet Mn12-acetate obeys a Curie-Weiss law, indicating a transition to a ferromagnetic phase at ∼0.9 K. With increasing magnetic field applied transverse to the easy axis, a marked change is observed in the temperature dependence of the susceptibility, and the suppression of ferromagnetism is considerably more rapid than predicted by mean-field theory for an ordered single crystal. Our results can instead be fit by a Hamiltonian for a random-field Ising ferromagnet in a transverse magnetic field, where the randomness derives from the intrinsic distribution of locally tilted magnetic easy axes …

Experimental Determination Of The Weiss Temperature Of Mn12-Ac And Mn12-Ac-Meoh, Christos Lampropoulos, Shiqi Li, Lin Bo, Bo Wen, M P. Sarachik, P Subedi, A D. Kent, Y Yeshurun, A J. Millis, S Mukherjee, G Christou

Christos Lampropoulos

We report measurements of the susceptibility in the temperature range from 3.5 to 6.0 K of a series of Mn12-ac and Mn12-ac-MeOH samples in the shape of rectangular prisms of length lc and square cross section of side la. The susceptibility obeys a Curie-Weiss law, χ=C/(T−θ), where θ varies systematically with sample aspect ratio. Using published demagnetization factors, we obtain θ for an infinitely long sample corresponding to intrinsic ordering temperatures Tc≈0.85 K and ≈0.74 K for Mn12-ac and Mn12-ac-MeOH, respectively. The difference in Tc for two materials that have nearly identical unit cell volumes and lattice constant ratios suggests …

Water Ice Films In Cryogenic Vacuum Chambers, Jesse Michael Labello

Doctoral Dissertations

The space simulation chambers at Arnold Engineering Development Complex (AEDC) allow for the testing and calibration of seeker sensors in cryogenic, high vacuum environments. During operation of these chambers, contaminant films can form on the components in the chamber and disrupt operation. Although these contaminant films can be composed of many molecular species, depending on the species outgassed by warm chamber components and any leaks or virtual leaks (pockets of gas trapped within a vacuum chamber) that may be present, water vapor is most common, and it will be the focus of this dissertation. In this dissertation, some properties of …

Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2 - 20 x 10^-50 strain² Hz^-1 and 5 - 35 x 10^-49 strain²Hz^-1sr^-1 for pointlike and extended sources, respectively. The latter result is the …

Particle Transport And Stochastic Acceleration In The Giant Lobes Of Centaurus A, Stephen O'Sullivan

Conference papers

The conditions within the giant lobes of Centaurus A are reviewed in light of recent radio and γ‐ray observations. Data from WMAP and ground‐based telescopes in conjunction with measurements from Fermi‐LAT constrain the characteristic field strength and the maximum electron energy. The implications for the transport of energetic particles are discussed in terms of residence times and cooling times within the lobes. Acceleration of electrons and UHECR via the second order Fermi mechanism is discussed.

New Limit On Time-Reversal Violation In Beta Decay, H. P. Mumm, T. E. Chupp, R. L. Cooper, K. P. Coulter, S. J. Freedman, B. K. Fujikawa, A. Garcia, Gordon L. Jones, J. S. Nico, A. K. Thompson, C. A. Trull, J. F. Wilderson, F. E. Wietfeldt

Articles

We report the results of an improved determination of the triple correlation DP . (p(e) x p(v)) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the standard model. Our result is D = [-0.96 +/- 1.89(stat) +/- 1.01(sys)] x 10(-4). The corresponding phase between g(A) and g(V) is phi(AV) = 180.013 degrees +/- 0.028 degrees (68% confidence level). This result represents the most sensitive measurement of D in nuclear beta decay.

Time Reversal Invariance Violating And Parity Conserving Effects In Neutron-Deuteron Scattering, Young-Ho Song, Rimantas Lazauskas, Vladimir Gudkov

Faculty Publications

Time reversal invariance violating and parity conserving effects for low-energy elastic neutron-deuteronscattering are calculated for meson exchange and effective field theory type potentials in a distorted wave-bornapproximation using realistic hadronic wave functions, obtained by solving three-body Faddeev equations inconfiguration space.

Fall 2010 Sci 2130: Quantum Physics: Information About Course: Learning Objectives, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Course Materials: Homework Overview, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Course Materials: Assignments, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

Fall 2010 Sci 2130: Quantum Physics: Information About Course: Course Syllabus, Stephen Holt

Stephen Holt

Modern Physics is based upon a few fundamental ideas that allow the explanation of phenomena that seem to defy consistency with traditional (Newtonian) physics. The most important of these (in the context of engineering applications) are the principles of quantum mechanics and statistical mechanics. This course will introduce the basic concepts of Modern Physics, with particular application to atoms, molecules and the materials utilized in modern electronics.

An Examination Of The Yang-Baxter Equation, Alexandru Cibotarica

Master's Theses

The Yang-Baxter equation has been extensively studied due to its application in numerous fields of mathematics and physics. This thesis sets out to analyze the equation from the viewpoint of the algebraic product of matrices, i.e., the composition of linear maps, with the intent of characterizing the solutions of the Yang-Baxter equation.

We begin by examining the simple case of 22 matrices where it is possible to fully characterize the solutions. We connect the Yang-Baxter equation to the Cecioni-Frobenius Theorem and focus on obtaining solutions to the Yang-Baxter equation for special matrices where solutions are more easily found. Finally, …