Astrophysics and Astronomy Commons^™

Taurus, Luis M. Torres Cantu

Natural Sciences Student Research Presentations

The purpose of this project was to gather information about the stars and objects in the constellation Taurus. This is a project for the Natural Sciences Poster Session at Parkland College.

Cygnus The Swan, Emily J. Oldham

Natural Sciences Student Research Presentations

The purpose of this project was to gather information about the stars and objects in the constellation Cygnus. This is a project for the Natural Sciences Poster Session at Parkland College.

Evidence Of Attenuation Of Vhe Blazar Spectra By Extragalactic Background Light, Cameron Allen

Physics

The spectrum of two blazar objects, 1ES 1959+650 and 1ES 2344+514, are analyzed for evidence of interactions with the Extragalactic Background Light (EBL), using combined data from the Very Energetic Radiation Imaging Telescope Array System and the Fermi Gamma-ray Space Telescope, By analyzing the distinct curvature across the combined spectrum, we infer that the very-high energy (VHE) gamma-rays must be attenuated by interactions with the EBL. We also find that the measured 1ES 1959+650 spectrum is sensitive to the intrinsic blazar model, with a preference for a power-law with an exponential cutoff (EPWL). The measured curvature is a combination of …

Lattice Study Of Quark And Glue Momenta And Angular Momenta In The Nucleon, M. Deka, T. Doi, Y. B. Yang, B. Chakraborty, S. J. Dong, Terrence Draper, M. Glatzmaier, M. Gong, H. W. Lin, Keh-Fei Liu, D. Mankame, N. Mathur, T. Streuer

Physics and Astronomy Faculty Publications

We report a complete calculation of the quark and glue momenta and angular momenta in the proton. These include the quark contributions from both the connected and disconnected insertions. The quark disconnected insertion loops are computed with Z₄ noise, and the signal-to-noise ratio is improved with unbiased subtractions. The glue operator is comprised of gauge-field tensors constructed from the overlap operator. The calculation is carried out on a 16³×24 quenched lattice at β=6.0 for Wilson fermions with κ=0.154, 0.155, and 0.1555, which correspond to pion masses at 650, 538, and 478 MeV, respectively. The chirally …

Kibble-Zurek Scaling In Holographic Quantum Quench: Backreaction, Sumit R. Das, Takeshi Morita

Physics and Astronomy Faculty Publications

We study gauge and gravity backreaction in a holographic model of quantum quench across a superfluid critical transition. The model involves a complex scalar field coupled to a gauge and gravity field in the bulk. In earlier work (arXiv:1211.7076) the scalar field had a strong self-coupling, in which case the backreaction on both the metric and the gauge field can be ignored. In this approximation, it was shown that when a time dependent source for the order parameter drives the system across the critical point at a rate slow compared to the initial gap, the dynamics in the critical region …

Note: Improved Line Strengths Of Rovibrational And Rotational Transitions Within The X3Σ⁻ Ground State Of Nh, James S.A. Brooke, Peter F. Bernath, Colin M. Western

Chemistry & Biochemistry Faculty Publications

Recently, a line list including positions and transition strengths was published for the NH X³Σ⁻ rovibrational and rotational transitions. The calculation of the transition strengths requires a conversion of transition matrix elements from Hund’s case (b) to (a). The method of this conversion has recently been improved during other work on the OH X²Π rovibrational transitions, by removing an approximation that was present previously. The adjusted method has been applied to the NH line list, resulting in more accurate transition strengths. An updated line list is presented that contains all possible transitions with v′ and …

Astronomy 102 Stars, Galaxies, The Universe Fall 2015, Erik Johnson

Astronomy Courses

No abstract provided.

Astronomy 102 Stars, Galaxies, The Universe Spring 2015, Erik Johnson

Astronomy Courses

No abstract provided.

Astronomy 101 Online The Solar System Summer 2015, Pam Friese, Katrina Wefel

Astronomy Courses

No abstract provided.

On X-Ray Pulsations In Beta Cephei-Type Variables, L. Oskinova, H. Todt, D. Huenemoerder, S. Hubrig, Richard Ignace, W.-R. Hamann, L. Balona

ETSU Faculty Works

Beta Cephei-type variables are early B-type stars that are characterized by oscillations observable in their optical light curves. At least one Beta Cep-variable also shows periodic variability in X-rays. Here we study the X-ray light curves in a sample of beta Cep-variables to investigate how common X-ray pulsations are for this type of stars. We searched the Chandra and XMM-Newton X-ray archives and selected stars that were observed by these telescopes for at least three optical pulsational periods. We retrieved and analyzed the X-ray data for kappa Sco, beta Cru, and alpha Vir. The X-ray light curves of these objects …

Identification Of Magnetite In Lunar Regolith Breccia 60016: Evidence For Oxidized Conditions At The Lunar Surface, Katherine H. Joy, Channon Visscher, Michael E. Zolensky, Takashi Mikouchi, Kenji Hagiya, Kazumasa Ohsumi, David A. Kring

Faculty Work Comprehensive List

Lunar regolith breccias are temporal archives of magmatic and impact bombardment processes on the Moon. Apollo 16 sample 60016 is an ‘ancient’ feldspathic regolith breccia that was converted from a soil to a rock at ~3.8 Ga. The breccia contains a small (70 × 50 μm) rock fragment composed dominantly of an Fe-oxide phase with disseminated domains of troilite. Fragments of plagioclase (An95-97), pyroxene (En74-75, Fs21-22,Wo3-4) and olivine (Fo66-67) are distributed in and adjacent to the Fe-oxide. The silicate minerals have lunar compositions that are similar to anorthosites. Mineral chemistry, synchrotron X-ray Absorption Near Edge Spectroscopy (XANES) and X-ray Diffraction …

Human Behavior During Spaceflight - Evidence From An Analog Environment, Kenny M. Arnaldi, Guy Smith, Jennifer E. Thropp

Journal of Aviation/Aerospace Education & Research

Spaceflight offers a multitude of stressors to humans living and working in space, originating from the external space environment and the life-support system. Future space participants may be ordinary people with different medical and psychosocial backgrounds who may not receive the intense spaceflight preparation of astronauts. Consequently, during a mission, a space participant’s mood and behavior could differ from a trained astronaut. This study was an exploratory research project that used an artificial habitat to replicate an orbital environment and the activities performed by humans in space. The study evaluated whether the type of environment affects mood and temperament. Two …

Interdisciplinary Connections Between Science & Theatre, Jessica N. Dotson

Theses and Dissertations

Abstract

INTERDISCIPLINARY CONNECTIONS BETWEEN SCIENCE & THEATRE

Jessica Nicole Dotson

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Fine Arts at Virginia Commonwealth University.

Virginia Commonwealth University, 2015.

Major Director: Dr. Noreen C. Barnes, Director of Graduate Studies, Associate Professor of Theatre

In the 1990s, astronomer Peter Usher was searching for new ways to teach his introductory astronomy class at Pennsylvania State University. He began to engage his students by searching for astronomical connections from other disciplines. His focus was turned to the arts, especially the works of William Shakespeare. Usher found, while …

An Economic Analysis Of Mars Exploration And Colonization, Clayton Knappenberger 15

Honor Scholar Theses

No abstract provided.

Detection Of Temporal Changes In Vegetative Cover On South Padre Island, Texas Using Image Classifications Derived From Aerial Color-Infrared Photographs, Ruben A. Mazariegos, Kenneth R. Summy, Frank W. Judd, Robert I. Lonard, James H. Everitt

Physics & Astronomy Faculty Publications

Supervised image classifications developed from 23 x 23 cm aerial color-infrared aerial photographs (1:5,000 scale) were used to evaluate temporal changes in vegetative cover occurring within three 150 x 300-m research sites on South Padre Island, Texas. Use of high-resolution digitized imagery (ground pixel resolution of ca. 0.1 m) and survey-grade GPS for positional measurements of ground control points (20-25 1.0m2 targets within each research site) resulted in consistently high levels of geometric accuracy, with root mean square errors (RMSEs) ranging between 0.397 – 2.867. Similarly, use of relatively simple information categories (dry and wet sand, live and dead vegetative …

Instrument For Precision Long-Term Ss-Decay Rate Measurements, M. J. Ware, Scott D. Bergeson, J. E. Ellsworth, M. Groesbeck, J. E. Hansen, D. Pace, J. Peatross

Faculty Publications

We describe an experimental setup for making precision measurements of relative ß-decay rates of ²²Na, ³⁶Cl, ⁵⁴Mn, ⁶⁰Co, ⁹⁰Sr, ¹³³Ba, ¹³⁷Cs, ¹⁵²Eu, and ¹⁵⁴Eu. The radioactive samples are mounted in two automated sample changers that sequentially position the samples with high spatial precision in front of sets of detectors. The set of detectors for one sample changer consists of four Geiger-Müller (GM) tubes and the other set of detectors consists of two NaI scintillators. The statistical uncertainty in the count rate is few times 0.01% per day for the GM …

Spectral Study Of Asteroids And Laboratory Simulation Of Asteroid Organics, Kelsey Hargrove

Electronic Theses and Dissertations

We investigate the spectra of asteroids at near- and mid-infrared wavelengths. In 2010 and 2011 we reported the detection of 3 ?m and 3.2-3.6 ?m signatures on (24) Themis and (65) Cybele indicative of water-ice and complex organics [1] [2] [3]. We further probed other primitive asteroids in the Cybele dynamical group and Themis family, finding diversity in the shape of their 3 ?m [4] [5] [6] and 10 ?m spectral features [4]. These differences indicated mineralogical and compositional variations within these asteroid populations. Also in the mid-infrared region we studied a larger population of asteroids belonging to the Bus …

A Method For Determining The Mass Composition Of Ultra-High Energy Cosmic Rays By Predicting The Depth Of First Interaction Of Individual Extensive Air Showers, Tolga Yapici

Dissertations, Master's Theses and Master's Reports - Open

Particle accelerators have been used to characterize the properties of particle and subatomic particles. The most advanced particle accelerators built, LHC, can run at 1017 eV. It is not possible with current technology to accelerate particle to the energies that can be detected by cosmic ray observatories.

In the past, by the direct measurements of cosmic rays, scientists discovered sub-atomic particles. Being accelerated to energies higher than 1018 eV, cosmic rays carry important information for particle physics. We have developed a method, which is a combination of Artificial Neural Networks and simple algebraic method that uses parameters from the extensive …

The Mass Profile And Shape Of Bars In The Spitzer Survey Of Stellar Structure In Galaxies (S4g) : Search For An Age Indicator For Bars., Taehyun Kim, Kartik Sheth, Dimitri A. Gadotti, Myung Gyoon Lee, Dennis Zaritsky, Bruce G. Elmegreen, E. Athanassoula, Albert Bosma, Benne W. Holwerda, Luis C. Ho, Sebastien Comeron, Johan H. Knapen, Joannah Hinz, Juan Carlos Munoz-Mateos, Santiago Erroz-Ferrer, Ronald J. Buta, Minjin Kim, Eija Laurikainen, Heikki Salo, Barry F. Madore, Jarkko Laine, Karin Menendez-Delmestre, Michael Regan, Bonita De Swardt, Armando Gil De Paz, Mark Seibert, Trisha Mizusawa

Faculty and Staff Scholarship

We have measured the radial light profiles and global shapes of bars using two-dimensional 3.6μm image decompositions for 144 face-on barred galaxies from the Spitzer Survey of Stellar Structure in Galaxies. The bar surface brightness profile is correlated with the stellar mass and bulge-to-total (B/T) ratio of their host galaxies. Bars in massive and bulge-dominated galaxies (B/T > 0.2) show a flat profile, while bars in less massive, disk-dominated galaxies (B/T ∼ 0) show an exponential, disk-like profile with a wider spread in the radial profile than in the bulge-dominated galaxies. The global two-dimensional shapes of bars, however, are rectangular/boxy, independent …

Question 1: Star Speeds; Question 2: Slurping Gasoline, Larry Weinstein

Physics Faculty Publications

One piece of evidence that the center of our galaxy contains a super-massive black hole came from measuring the speed of a star orbiting that black hole. What is the maximum speed of that star?

If instead of carrying their gas in fuel tanks, cars “slurped up” a stream of gas as they drove, how thick a stream of gas would each car need?

Spectroscopic Confirmation Of The Existence Of Large, Diffuse Galaxies In The Coma Cluster, Pieter Van Dokkum, Aaron Romanowsky, Roberto Abraham, Jean Brodie, Charlie Conroy, Marla Geha, Allison Merritt, Alexa Villaume, Jielai Zhang

Faculty Publications

No abstract provided.

Spectral Results For The Blue Plume Stars In Canis Major Overdensity, Mirza Sharoz Rafiul Islam

Theses and Dissertations--Physics and Astronomy

We present distances and kinematics and look at the possible populations for the blue plume (BP) stars in the Canis Major Overdensity (CMa). We conducted a medium resolution spectral survey on the BP stars (N=303) in CMa (centered at l = 238° ; b = -8°) using the data from AAOmega Spectrograph. We used a modified version of the Statistics-sensitive Non-linear Iterative Peak-clipping (SNIP) algorithm to normalize our fluxed absorption spectra. After determining the radial velocities from measurements of strong absorption features for the stars we use a Bayesian analysis of spectral feature strengths and photometric colors to determine Teff, …

Characterizing The Nearest Young Moving Groups, Kyle Mccarthy

Theses and Dissertations--Physics and Astronomy

Moving groups are associations of stars which originated from the same star forming region. These groups are typically young (< 200 Myr) since they have not dissipated into the galactic field population. Over the last 15 years, roughly 10 such moving groups have been found with distances < 150 pc (7 with distances < 100 pc), each with a unique velocity and position.

This work first investigates the likelihood to resolve star from two moving groups (AB Doradus and Beta Pictoris) using high spacial resolution optical interferrometry and found 5 AB Doradus stars and 1 Beta Pictoris star with declinations > -30 could be spacially resolved.

To more deeply characterize individual groups, we used the 2.7m telescope at the McDonald Observatory to observe 10 proposed AB Doradus stars and 5 proposed Octans-Near stars (3 probable members, 2 possible) with high resolution (R ~60,000) optical …

Feldspathic Rocks On Mars: Compositional Constraints From Infrared Spectroscopy And Possible Formation Mechanisms, Deanne Rogers, Hanna Nekvasil

Department of Geosciences Faculty Publications

Rare feldspar-dominated surfaces on Mars were previously reported based on near-infrared (NIR) spectral data and were interpreted to consist of anorthosite or felsic rocks. Using thermal infrared (TIR) data over the feldspar detections with the largest areal extent in Nili Patera and Noachis Terra, we rule out felsic interpretations. Basaltic or anorthositic compositions are consistent with TIR measurements, but the geologic contexts for these regions do not support a plutonic origin. Laboratory NIR spectral measurements demonstrate that large plagioclase crystals (>~840 μm) can be detected in mixtures with as much as 50 vol % mafics, which is higher than …

First Measurement Of The Polarization Observable E In The P→ (Ɣ→, Π+) In Reaction Up To 2.25 Gev, S. Strauch, W. J. Briscoe, M. Döring, E. Klempt, V. A. Nikonov, E. Pasyuk, D. Rönchen, A.V. Sarantsev, I. Strakovsky, R. Workman, K. P. Adhikari, D. Adikaram, L. El Fassi

Physics Faculty Publications

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction ɣ^→p^→→π+n, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. 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-L multipoles contribute. The data have been …

Prospects For Detection Of Extragalactic Stellar Black Hole Binaries In The Nearby Universe, Matthew Benacquista, Jesus Hinojosa, Alberto Mata, Krzysztof Belczynski

Physics & Astronomy Faculty Publications

Stellar mass black hole binaries have individual masses between 10-80 solar masses. These systems may emit gravitational waves at frequencies detectable at Megaparsec distances by space-based gravitational wave observatories. In a previous study, we determined the selection effects of observing these systems with detectors similar to the Laser Interferometer Space Antenna by using a generated population of binary black holes that covered a reasonable parameter space and calculating their signal-to-noise ratio. We further our study by populating the galaxies in our nearby (less than 30 Mpc) universe with binary black hole systems drawn from a distribution found in the Synthetic …

Precision Measurements Of Aⁿ1 In The Deep Inelastic Regime, D. S. Parno, D. Flay, M. Posik, M. Canan, C. Hyde, The Jefferson Lab Hall A Collaboration

Physics Faculty Publications

We have performed precision measurements of the double-spin virtual-photon asymmetry A₁ on the neutron in the deep inelastic scattering regime, using an open-geometry, large-acceptance spectrometer and a longitudinally and transversely polarized ³He target. Our data cover a wide kinematic range 0.277 <= x <= 0.548 at an average Q² value of 3.078(GeV/c)², doubling the available high-precision neutron data in this xrange. We have combined our results with world data on proton targets to make a leading-order extraction of the ratio of polarized-to-unpolarized parton distribution functions for up quarks and for down quarks in the same kinematic range. Our data are consistent with …

Evidence For Transverse-Momentum- And Pseudorapidity-Dependent Event-Plane Fluctuations In Pbpb And P Pb Collisions, Vardan Khachatryan, Vallary Bhopatkar, Marcus Hohlmann, H. Kalakhety, D. Mareskas-Palcek, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A systematic study of the factorization of long-range azimuthal two-particle correlations into a product of single-particle anisotropies is presented as a function of pT and η of both particles and as a function of the particle multiplicity in PbPb and pPb collisions. The data were taken with the CMS detector for PbPb collisions at sNN=2.76 TeV and pPb collisions at sNN=5.02 TeV, covering a very wide range of multiplicity. Factorization is observed to be broken as a function of both particle pT and η. When measured with particles of different pT, the magnitude of the factorization breakdown for the second …

Search For Dark Photons From Neutral Meson Decays In P+P And D+ Au Collisions At √Snn =200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The standard model (SM) of particle physics is spectacularly successful, yet the measured value of the muon anomalous magnetic moment (g-2)μ deviates from SM calculations by 3.6σ. Several theoretical models attribute this to the existence of a "dark photon," an additional U(1) gauge boson, which is weakly coupled to ordinary photons. The PHENIX experiment at the Relativistic Heavy Ion Collider has searched for a dark photon, U, in π0,η→γe+e- decays and obtained upper limits of O(2×10‐⁶) U-γ mixing at 90% C.L. for the mass range 30< mᵤ < 90 MeV/c². Combined with other experimental limits, the remaining region in the U-γ mixing parameter space that can explain the (g-2)ᵤ deviation from its SM value is nearly completely excluded at the 90% confidence level, with only a small region of 29

Systematic Study Of Azimuthal Anisotropy In Cu + Cu And Au + Au Collisions At √Snn =62.4 And 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

We have studied the dependence of azimuthal anisotropy v₂ for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v₂ as a function of transverse momentum pT and centrality in Au+Au collisions at sNN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v₂ values as the collision energy is reduced from 200 to 62.4 GeV. The decrease is larger in the more peripheral collisions. By examining both Au+Au and Cu+Cu collisions we find that v₂ depends both on eccentricity and the …