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Full-Text Articles in Physics

P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales Oct 2019

P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales

Celebration of Research and Creative Scholarship

The LIGO and Virgo detectors have made a total of 11 confirmed measurements of gravitational waves, the faint ripples in the fabric of spacetime predicted by Einstein’s theory of general relativity. Ten of these gravitational wave events were caused by the inspiral, collision, and merging of a pair of black holes and the remaining event by a pair of neutron stars. These measurements have helped us learn about the objects that produced the gravitational waves. Regular candidate detections are now shared in real time with both astronomers and the public.


P-43 Doing Astronomy With Gravitational Waves, Tiffany Summerscales Oct 2018

P-43 Doing Astronomy With Gravitational Waves, Tiffany Summerscales

Celebration of Research and Creative Scholarship

With the first detection of gravitational waves on September 14, 2015, the new era of gravitational wave astronomy began. Gravitational wave detections, along with observations made by optical telescopes, have given us new information about the universe. This includes new estimates of the numbers of black holes in the universe and their properties, as well as confirming theories about the sources of some gamma ray bursts and how those sources produce heavy elements.


Growth And Magnetooptical Properties Of Anisotropic Tbf3 Single Crystals, Uygun V. Valiev, Denis N. Karimov, Gary W. Burdick, Rakhim Rakhimov, Vasiliy O. Pelenovich, Dejun Fu Jun 2017

Growth And Magnetooptical Properties Of Anisotropic Tbf3 Single Crystals, Uygun V. Valiev, Denis N. Karimov, Gary W. Burdick, Rakhim Rakhimov, Vasiliy O. Pelenovich, Dejun Fu

Faculty Publications

The present paper investigates the Faraday effect and absorption and luminescence spectra of single-crystal TbF3 measured at 90 K and 300 K. The optical-quality single-phase TbF3 crystals (structural type β-YF3) were grown by the Bridgman technique. Faraday rotation angles were measured at remagnetization along the [100] crystallographic axis. Low temperature optical measurements were carried out along the [100] axis. “Quasi-doublet” sublevels with energy at 0 cm-1, 65 cm-1 and 190 cm-1, and also a singlet sublevel with energy at 114 cm-1 located in the ground 7F6 multiplet were determined from the low temperature ...


Searching For The Origins Of Matter, Joshua L. Barrow May 2017

Searching For The Origins Of Matter, Joshua L. Barrow

Andrews Research Conference

The big bang and inflation are experimentally confirmed by multitudes of astronomical observations, yet theoretical tension still exists upon a very important question: why is there something rather than nothing? In other words, why are there unequal amounts of matter and antimatter? Why did a supposedly initially symmetric state not annihilate perfectly?

The breaking of this symmetry has allowed for all of material existence--also known as baryogenesis, the prevalence of matter over antimatter--and yields the theoretical possibility of direct detection by observation of baryon number violating mechanisms, which have previously never been observed.

One such plausible mechanism can be found ...


Graphene Kirigami And Its Use In Biocompatible Strain Sensor, Erik Vyhmeister Dec 2016

Graphene Kirigami And Its Use In Biocompatible Strain Sensor, Erik Vyhmeister

Honors Theses

Graphene's large fracture strain (>30%), chemical inertness, and piezoresistive nature make it well suited for use as a biocompatible strain sensor. A rectangular multilayer strucutre with graphene as its operative component was designed. It consists of a bottom layer of SU-8, a center layer of graphene, and a top layer of SU-8 and gold, with gold acting as the electrical contact. Kirigami-style patterning is applied via photolithography and oxygen plasma etching, allowing for a greater fracture strain. Additionally, the kirigami affects the stress concentraton in the graphene, affecting its piezoresistive gauge factor. The complete (patterned) structure exhibited a fracture ...


Furthering Sustainable Energy: Lauber Martins Joins The Physics Faculty Aug 2016

Furthering Sustainable Energy: Lauber Martins Joins The Physics Faculty

Andrews Agenda: Campus News

This article introduces Lauber De Souza Martins, who joined Andrews University’s Department of Physics as an assistant professor in January 2016. He specializes in thermodynamics and sustainable energy. He is researching "how to use fuel cells as a backup system for stationary applications, like schools or hospitals".


Evaluating The Efficacy Of Educational Games In Promoting Interest And Understanding Of Gravitational Wave Physics, Jonathan Wheeler Mar 2016

Evaluating The Efficacy Of Educational Games In Promoting Interest And Understanding Of Gravitational Wave Physics, Jonathan Wheeler

Honors Theses

The LIGO Scientific Collaboration Education and Public Outreach group seeks to ameliorate the lack of public understanding of gravitational wave physics. One such effort is Black Hole Pong, a remake of the 1972 arcade classic developed by researchers at University of Birmingham, UK. Black Hole Pong differs from other educational games in that it stretches the laws of physics to make the user experience more exciting. Another effort has been my own work in developing a game called Chickens in Space where players can create mass, which coalesces and eventually forms black holes, which serve as obstacles to the players ...


Evaluating The Efficacy Of Gravitational Wave Games In Arousing Interest And Promoting Understanding Of Gravitational Wave Research, Jonathan Wheeler Feb 2016

Evaluating The Efficacy Of Gravitational Wave Games In Arousing Interest And Promoting Understanding Of Gravitational Wave Research, Jonathan Wheeler

Posters, Presentations, and Papers

The LIGO Scientific Collaboration’s Education and Public Outreach Group seeks to ameliorate the lack of public understanding of gravitational wave physics. I present the results of a set of pre-tests and post-tests from a public high school which measures Black Hole Pong’s effectiveness in teaching the concepts and benefits of gravitational wave astronomy. Results of this test can be used in the development of other outreach games, such as Black Hole Master and Chickens in Space.


Physics Major Scores Highest Possible On Gre: Robbie Polski Credits Internship, Good Prep, Professors, Samuel Fry Nov 2015

Physics Major Scores Highest Possible On Gre: Robbie Polski Credits Internship, Good Prep, Professors, Samuel Fry

Andrews Agenda: Campus News

"Robbie Polski, physics major at Andrews University, achieved the highest possible score on his GRE Physics Subject Test—an exam intended to measure the extent of an examinee’s mastery of the fundamental principles of physics."


Will We Find Gravity Waves?: Physics Professor Involved In Ground-Breaking Research, Danni Francis Nov 2015

Will We Find Gravity Waves?: Physics Professor Involved In Ground-Breaking Research, Danni Francis

Andrews Agenda: Campus News

"The world of science is effectively on the edge of its seat as researchers are close to making revolutionary discoveries in the area of gravity and gravitational waves. Tiffany Summerscales, associate professor of physics at Andrews University, is an active researcher with the Laser Interferometer Gravitational-Wave Observatory (LIGO) collaboration."


Locating Gravitational Waves With Bayeswave, Belinda Cheeseboro, Tiffany Summerscales Mar 2015

Locating Gravitational Waves With Bayeswave, Belinda Cheeseboro, Tiffany Summerscales

Posters, Presentations, and Papers

LIGO is the Laser Interferometer Gravitational Wave Observatory. Its mission is to detect gravitational waves that could be caused by the interaction of massive gravitating bodies such as coalescing black holes, inspiraling neutron stars, etc. BayesWave is an algorithm that can analyze possible gravitational wave event data and determine the properties of candidate events such as sky location. This algorithm uses a combination of Bayesian probability theory and the Reverse Jump Markov chain Monte Carlo (RJMcMC) method to accomplish this goal. BayesWave is able to simultaneously model the gravitational wave signal the noise by using multi-component models. It uses the ...


Accessing Information Using Lvalert And Python, Belinda Cheeseboro, Tiffany Summerscales Ph.D. Jul 2014

Accessing Information Using Lvalert And Python, Belinda Cheeseboro, Tiffany Summerscales Ph.D.

Posters, Presentations, and Papers

GraCEDb is a database that stores events that could possibly produce gravitational waves. By using the notification system, LVAlert, we can develop a program in python to extract necessary information from that event and store it in a usable data structure. That data can then be analyzed by our algorithms to extract gravitational waveform data from the detectors.


Measurement Of D^*\Pm Production In Deep Inelastic Scattering At Hera, Margarita C. K. Mattingly, Zeus Collaboration Jan 2014

Measurement Of D^*\Pm Production In Deep Inelastic Scattering At Hera, Margarita C. K. Mattingly, Zeus Collaboration

Faculty Publications

The production of D∗± mesons in deep inelastic ep scattering has been measured for exchanged photon virtualities 5 < Q2<1000GeV2, using an integrated luminosity of 363 pb−1 with the ZEUS detector at HERA. Differential cross sectionshave been measured and compared to next-to-leading-order QC D calculations. The cross-sections are used to extract the charm contribution to the protonstructure functions, expressed in terms of the reduced charm cro ss section, σc̄cred. Theoretical calculations based on fits to inclusive HERA data are compared to the results.


Measurement Of Charm Fragmentation Fractions In Photoproduction At Hera, Margarita C. K. Mattingly, Zeus Collaboration Jun 2013

Measurement Of Charm Fragmentation Fractions In Photoproduction At Hera, Margarita C. K. Mattingly, Zeus Collaboration

Faculty Publications

The production of D^0, D^*+, D^+, D_s+ and Lambda_c^+ charm hadrons and their antiparticles in ep scattering at HERA has been studied with the ZEUS detector, using a total integrated luminosity of 372 pb^-1. The fractions of charm quarks hadronising into a particular charm hadron were derived. In addition, the ratio of neutral to charged D-meson production rates, the fraction of charged D mesons produced in a vector state, and the stangeness-suppression factor have been determined. The measurements have been performed in the photoproduction regime. The charm hadrons were reconstructed in the range of transverse momentum p_T >3 ...


Measurement Of D^\Pm Production In Deep Inelastic Ep Scattering With The Zeus Detector At Hera, Margarita C. K. Mattingly, Zeus Collaboration Feb 2013

Measurement Of D^\Pm Production In Deep Inelastic Ep Scattering With The Zeus Detector At Hera, Margarita C. K. Mattingly, Zeus Collaboration

Faculty Publications

Charm production in deep inelastic ep scattering was measured with the ZEUS detector using an integrated luminosity of 354 pb^{-1}. Charm quarks were identified by reconstructing D^{+} mesons in the D^{+} -> K^{-} pi^{+} pi^{+} decay channel. Lifetime information was used to reduce combinatorial background substantially. Differential cross sections were measured in the kinematic region 5 < Q^{2} < 1000 GeV^{2}, 0.02 < y < 0.7, 1.5 < p_{T}(D^{+}) < 15 GeV and |eta(D^{+})| < 1.6, where Q^{2} is the photon virtuality, y is the inelasticity, and p_{T}(D^{+}) and eta(D^{+}) are the transverse momentum and the pseudorapidity of the D^{+} meson, respectively. Next-to-leading-order QCD predictions are compared to the data. The charm contribution, F_{2}^{cc}, to the proton structure-function F_{2} was extracted.


Production Of Z 0 Bosons In Elastic And Quasi-Elastic Ep Collisions At Hera, Margarita C. K. Mattingly Oct 2012

Production Of Z 0 Bosons In Elastic And Quasi-Elastic Ep Collisions At Hera, Margarita C. K. Mattingly

Faculty Publications

The production of Z0 bosons in the reaction ep -> eZ0p*, where p* stands for a proton or a low-mass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb-1 of integrated luminosity. The Z0 was measured in the hadronic decay mode. The elasticity of the events was ensured by a cut on eta_max < 3.0, where eta_max is the maximum pseudorapidity of energy deposits in the calorimeter defined with respect to the proton beam direction. A signal was observed at the Z0 mass. The cross section of the reaction ep -> eZ0p* was measured to be sigma(ep -> eZ0p*) = 0.13 +/- 0.06 (stat.) +/- 0.01 (syst.) pb, in agreement with the Standard Model prediction of 0 ...


Combination And Qcd Analysis Of Charm Production Cross Section Measurements In Deep-Inelastic Ep Scattering At Hera, Margarita C. K. Mattingly, Zeus Collaboration, H1 Collaboration Oct 2012

Combination And Qcd Analysis Of Charm Production Cross Section Measurements In Deep-Inelastic Ep Scattering At Hera, Margarita C. K. Mattingly, Zeus Collaboration, H1 Collaboration

Faculty Publications

Measurements of open charm production cross sections in deep-inelastic ep scattering at HERA from the H1 and ZEUS Collaborations are combined. Reduced cross sections sigma_red^{c\bar{c}} for charm production are obtained in the kinematic range of photon virtuality 2.5


Analysis Of The Spectra Of Trivalent Erbium In Multiple Sites Of Hexagonal Aluminum Nitride, John B. Gruber, Ulrich Vetter, Gary W. Burdick, Zachery D. Fleishman, Larry D. Merkle, Takashi Taniguchi, Yuan Xiaoli, Takashi Sekiguchi, Daniel Jurgens, Hans Hofsass Sep 2012

Analysis Of The Spectra Of Trivalent Erbium In Multiple Sites Of Hexagonal Aluminum Nitride, John B. Gruber, Ulrich Vetter, Gary W. Burdick, Zachery D. Fleishman, Larry D. Merkle, Takashi Taniguchi, Yuan Xiaoli, Takashi Sekiguchi, Daniel Jurgens, Hans Hofsass

Faculty Publications

The 12 K cathodoluminescence spectra of Er3+ doped into single crystals of aluminum nitride (2H-AlN) in the hexagonal phase are reported between 320 nm and 775 nm. The emission spectra represent transitions from the lower Stark level of 2P(3/2) to the Stark levels of the 4I(15/2), 4I(13/2), 4I(11/2), 4I(9/2), 4F(9/2), and 4S(3/2) multiplet manifolds of Er3+(4f(11)). Emission spectra from 4S(3/2) to 4I(15/2) are also reported. All observed strong line emission are accounted for in terms of two principle sites, denoted ...


Crystal Field And Zeeman Splittings For Energy Levels Of Nd3+ In Hexagonal Aln, John B. Gruber, Gary W. Burdick, Ulrich Vetter, Brandon Mitchell, Volkmar Dierolf, Hans Hofsass Sep 2012

Crystal Field And Zeeman Splittings For Energy Levels Of Nd3+ In Hexagonal Aln, John B. Gruber, Gary W. Burdick, Ulrich Vetter, Brandon Mitchell, Volkmar Dierolf, Hans Hofsass

Faculty Publications

The crystal-field and Zeeman splittings of the energy levels of Nd3+(4f3) 2S+1LJ in hexagonal phase AlN have been investigated. The multiplet manifolds of Nd3+(4f3) analyzed include the ground state, 4I9/2, and excited states 4I11/2, 4I13/2, 4F3/2, 4F5/2, 2H(2)9/2, 4F7/2, 4S3/2, 4G5/2, and 2G7/2. Experimental energy levels were obtained from analyses of the 12 K cathodoluminescence spectra from Nd3+-implanted films of AlN, and from the 15 K photoluminescence excitation spectra and the site-selective combined excitation-emission spectra (CEES) recently reported for in situ Nd-doped hexagonal AlN ...


Measurement Of High-Q2 Neutral Current Deep Inelastic E+P Scattering Cross Sections With A Longitudinally Polarised Positron Beam At Hera, Margarita Mattingly, Zeus Collaboration Aug 2012

Measurement Of High-Q2 Neutral Current Deep Inelastic E+P Scattering Cross Sections With A Longitudinally Polarised Positron Beam At Hera, Margarita Mattingly, Zeus Collaboration

Faculty Publications

Measurements of neutral current cross sections for deep inelastic scattering in e+p collisions at HERA with a longitudinally polarised positron beam are presented. The single-differential cross-sections dσ/dQ2, dσ/dx and dσ/dy and the reduced cross-section ˜σ were measured in the kinematic region Q2 > 185GeV2 and y < 0.9, where Q2 is the four-momentum transfer squared, x the Bjorken scaling variable, and y the inelasticity of the interaction. The measurements were performed separately for positively and negatively polarised positron beams. The measurements are based on an integrated luminosity of 135.5 pb−1 collected with the ZEUS detector in 2006 and 2007 at a centre-of-mass energy of 318GeV. The structure functions F˜3 and F Z 3 were determined by combining the e+p results presented in this paper with previously published e−p neutral current results. The asymmetry parameter A+ is used to demonstrate the parity violation predicted in electroweak interactions. The measurements are well described by the predictions of the Standard Model.


A Dialogue Between Contemporary Perspectives And Ellen White On Divine Action And Quantum Physics, Michael F. Younker Jan 2012

A Dialogue Between Contemporary Perspectives And Ellen White On Divine Action And Quantum Physics, Michael F. Younker

Journal of the Adventist Theological Society

No abstract provided.


New Physics Professor Returns To Alma Mater, Bjorn Karlman Oct 2006

New Physics Professor Returns To Alma Mater, Bjorn Karlman

Lake Union Herald

No abstract provided.


Teacher In The Spotlight, Aaron Beaumont Dec 2004

Teacher In The Spotlight, Aaron Beaumont

Lake Union Herald

No abstract provided.


Smartlabs Provides Hands-On Physics Experience, Erin Heldstab Aug 2004

Smartlabs Provides Hands-On Physics Experience, Erin Heldstab

Lake Union Herald

No abstract provided.