An X-Rays Survey Of The Young Stellar Population Of The Lynds 1641 And Iota Orionis Regions, 2013 Harvard University
An X-Rays Survey Of The Young Stellar Population Of The Lynds 1641 And Iota Orionis Regions, I. Pillitteri, S. J. Wolk, S. T. Megeath, L. Allen, J. Bally, Marc Gagné, R. A. Gutermuth, L. Hartman, G. Micela, P. Myers, J. M. Oliveira, S. Sciortino, F. Walter, L. Rebull, J. Stauffer
Earth & Space Sciences Faculty Publications
We present an XMM-Newton survey of the part of Orion A cloud south of the Orion Nebula. This survey includes the Lynds 1641 (L1641) dark cloud, a region of the Orion A cloud with very few massive stars and hence a relatively low ambient UV flux, and the region around the O9 III star Orionis. In addition to proprietary data, we used archival XMM data of the Orion Nebula Cluster (ONC) to extend our analysis to a major fraction of the Orion A cloud. We have detected 1060 X-ray sources in L1641 and Ori region. About 94% of the sources …
A Biodistribution And Toxicity Study Of Cobalt Dichloride–Nacetyl Cysteine (C4) As An Implantable Mri Marker For Prostate Cancer Treatment, 2013 The University of Texas Rio Grande Valley
A Biodistribution And Toxicity Study Of Cobalt Dichloride–Nacetyl Cysteine (C4) As An Implantable Mri Marker For Prostate Cancer Treatment, Steven J. Frank, Mary J. Johansen, Karen S. Martirosyan, Mihai Gagea, Carolyn S. Van Pelt
Physics and Astronomy Faculty Publications and Presentations
Purpose—C4, a cobalt dichloride–N-acetyl cysteine complex, is being developed as a positivesignal magnetic resonance imaging (MRI) marker to localize implanted radioactive seeds in prostate brachytherapy. We evaluated the toxicity and biodistribution of C4 in rats with the goal of simulating systemic effects of potential leakage from C4 MRI markers within the prostate.
Methods—9 μl doses (equivalent to leakage from 120 markers in a human) of control (0.9% sodium chloride), 1% (proposed for clinical use) and 10% C4 solution were injected into the prostates of male Sprague-Dawley rats via laparotomy. Organ toxicity and cobalt disposition in plasma, tissues, feces …
The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, 2013 Tennessee State University
The Spectroscopic Orbits Of Five Solar-Type, Single-Lined Binaries, Francis C. Fekel, Samira Rajabi, Matthew W. Muterspaugh, Michael H. Williamson
Information Systems and Engineering Management Research Publications
We have determined spectroscopic orbits for five single-lined spectroscopic binaries, HD 100167, HD 135991, HD 140667, HD 158222, HD 217924. Their periods range from 60.6 to 2403 days and the eccentricities from 0.20 to 0.84. Our spectral classes for the stars confirm that they are of solar type, F9–G5, and all are dwarfs. Their [Fe/H] abundances, determined spectroscopically, are close to the solar value and on average are 0.12 greater than abundances from a photometric calibration. Four of the five stars are rotating faster than their predicted pseudosynchronous rotational velocities.
Quantum Man, 2013 Claremont Colleges
Quantum Man, Julian Voss-Andreae
The STEAM Journal
According to quantum physics, the world is fundamentally quite different than it seems. Drawing inspiration from the underlying nature of reality, former quantum physicist Julian Voss-Andreae created an image of a walking human as a quantum object. Made up of parallel sheets of steel, the sculpture is a metaphor for the counter-intuitive world of quantum physics. Symbolizing the dual nature of matter with the appearance of classical reality on the surface and cloudy quantum behavior underneath, the sculpture seems to consist of solid steel when seen from the front, but dissolves into almost nothing when seen from the side.
Battery Energy Storage System In Solar Power Generation, 2013 Rajasthan Technical University Kota
Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er., Deepa Sharma
Radhey Shyam Meena
Grid-connected solar PV dramatically changes the load profile of an electric utility customer. The expected widespread adoption of solar generation by customers on the distribution system poses significant challenges to system operators both in transient and steady state operation, from issues including voltage swings, sudden weather-induced changes in generation, and legacy protective devices designed with one-way power flow in mind
Radiative Cooling In Collisionally Ionized And Photoionized Plasmas, 2013 University of Kentucky
Radiative Cooling In Collisionally Ionized And Photoionized Plasmas, Matt Lykins, Gary J. Ferland, Ryan L. Porter, Peter A. M. Van Hoof, R. J. R. Williams, Orly Gnat
Physics and Astronomy Faculty Publications
We discuss recent improvements in the calculation of the radiative cooling in both collisionally ionized and photoionized plasmas. We are extending the spectral simulation code CLOUDY so that as much as possible of the underlying atomic data are taken from external data bases, some created by others and some developed by the CLOUDY team. This paper focuses on recent changes in the treatment of many stages of ionization of iron, and discusses its extensions to other elements. The H- and He-like ions are treated in the isoelectronic approach described previously. Fe II is a special case treated with a large …
Asymmetry Of Magnetosheath Flows And Magnetopause Shape During Low Alfvén Mach Number Solar Wind, 2013 Universite de Toulouse
Asymmetry Of Magnetosheath Flows And Magnetopause Shape During Low Alfvén Mach Number Solar Wind, B. Lavraud, E. Larroque, E. Budnik, V. Génot, J. E. Borovsky, M. W. Dunlop, K. Nykyri, Et Al.
Publications
Previous works have emphasized the significant influence of the solar wind Alfvén Mach number (MA) on magnetospheric dynamics. Here we report statistical, observational results that pertain to changes in the magnetosheath flow distribution and magnetopause shape as a function of solar wind MA and interplanetary magnetic field (IMF) clock angle orientation. We use all Cluster 1 data in the magnetosheath during the period 2001–2010, using an appropriate spatial superposition procedure, to produce magnetosheath flow distributions as a function of location in themagnetosheath relative to the IMF and other parameters. The results demonstrate that enhanced flows in the magnetosheath are expected …
Quantifying Night Sky Fluctuations: Striving For A Multi-Messenger Astronomy, 2013 Utah State University
Quantifying Night Sky Fluctuations: Striving For A Multi-Messenger Astronomy, Rachel K. Nydegger, Shane L. Larson Ph.D.
Rachel Nydegger Rozum
With LIGO coming back online soon, astronomers are attempting to solve the problems involved with coupling gravitational observations with electromagnetic telescope observations. To do this, my project aims to create all-sky surveys to characterize natural variability to reduce "false-alarm" rates in detections of gravitational emissions.
Quantifying Night Sky Fluctuations: Striving For A Multi-Messenger Astronomy, 2013 Utah State University
Quantifying Night Sky Fluctuations: Striving For A Multi-Messenger Astronomy, Rachel K. Nydegger, Shane L. Larson Ph.D.
Browse All Undergraduate research
With LIGO coming back online soon, astronomers are attempting to solve the problems involved with coupling gravitational observations with electromagnetic telescope observations. To do this, my project aims to create all-sky surveys to characterize natural variability to reduce "false-alarm" rates in detections of gravitational emissions.
Effects Of Different Geomagnetic Storm Drivers On The Ring Current: Crcm Results, 2013 Trinity University
Effects Of Different Geomagnetic Storm Drivers On The Ring Current: Crcm Results, W D. Cramer, Niescja E. Turner, M C. Fok, N Y. Buzulukova
Physics and Astronomy Faculty Research
The storm-time magnetic disturbance at the Earth's equator, as commonly measured by the Dst index, is induced by currents in the near-Earth magnetosphere. The ring current is generally considered the most important contributor, but other magnetospheric currents have also been found to have significant effects. Of the two main types of solar geomagnetic storm drivers, Coronal Mass Ejections (CMEs) tend to have a much greater impact on Dst than Corotating Interaction Regions (CIRs). Ring current models have been found to underestimate Dst, particularly during storms driven by CIRs. One possible explanation is that the models neglect to handle some aspect …
How To Find Killing Vectors, 2013 Utah State University
How To Find Killing Vectors, Charles G. Torre
How to... in 10 minutes or less
We show how to compute the Lie algebra of Killing vector fields of a metric in Maple using the commands KillingVectors and LieAlgebraData. A Maple worksheet and a PDF version can be found below.
Modeling Spiral Galaxy Surface Luminosity To Explain Non-Uniform Inclination Distributions, 2013 Utah State University
Modeling Spiral Galaxy Surface Luminosity To Explain Non-Uniform Inclination Distributions, Jordan C. Rozum, Shane L. Larson
Jordan Rozum
The distribution of spiral and bar galaxy inclination angles is expected to be uniform. However, analysis of several major galaxy catalogs shows this is not the case; galaxies oriented near edge-on are significantly more common in these catalogs. In an attempt to explain this discrepancy, we have developed a galaxy simulation code to compute the appearance of a spiral type galaxy as a function of its morphological parameters. We examine the dependence of observed brightness upon inclination angle by using smooth luminous mass density and ISM density distributions. The luminous component is integrated along a particular line of sight, thus …
A Short Introduction To Numerical Linked-Cluster Expansions, 2013 The Pennsylvania State University
A Short Introduction To Numerical Linked-Cluster Expansions, Baoming Tang, Ehsan Khatami, Marcos Rigol
Faculty Publications
We provide a pedagogical introduction to numerical linked-cluster expansions (NLCEs). We sketch the algorithm for generic Hamiltonians that only connect nearest-neighbor sites in a finite cluster with open boundary conditions. We then compare results for a specific model, the Heisenberg model, in each order of the NLCE with the ones for the finite cluster calculated directly by means of full exact diagonalization. We discuss how to reduce the computational cost of the NLCE calculations by taking into account symmetries and topologies of the linked clusters. Finally, we generalize the algorithm to the thermodynamic limit, and discuss several numerical resummation techniques …
Prospects For Observing Ultracompact Binaries With Space-Based Gravitational Wave Interferometers And Optical Telescopes., 2013 Maryland Center for Fundamental Physics, Department of Physics, University of Maryland
Prospects For Observing Ultracompact Binaries With Space-Based Gravitational Wave Interferometers And Optical Telescopes., T. B. Littenberg, Shane L. Larson, G. Nelemans Department Of Astrophysics, Radboud University Nijmegen, N. J. Cornish
All Physics Faculty Publications
Space-based gravitational wave interferometers are sensitive to the galactic population of ultra-compact binaries. An important subset of the ultra-compact binary popula- tion are those stars that can be individually resolved by both gravitational wave in- terferometers and electromagnetic telescopes. The aim of this paper is to quantify the multi-messenger potential of space-based interferometers with arm-lengths between 1 and 5 Gm. The Fisher Information Matrix is used to estimate the number of binaries from a model of the Milky Way which are localized on the sky by the gravitational wave detector to within 1 and 10 deg2 and bright enough to …
The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, 2013 Tennessee State University
The Spectroscopic Orbit Of The K-Giant Binary Γ Canis Minoris, Francis C. Fekel, Michael H. Williamson, Michael Weber, Klaus G. Strassmeier, Dimitri Pourbaix
Information Systems and Engineering Management Research Publications
We have determined an improved orbit for the bright, evolved, double lined binary γ Canis Minoris. The system has an orbital period of 389.31 days and an eccentricity of 0.2586. We have revised the secondary to primary mass ratio to 0.987. The spectral types of the primary and secondary are K4 III and K1: III, respectively, and the components have a V magnitude difference of 2.2. Orbital fits to the Hipparcos astrometry are not definitive, but they suggest an orbital inclination of ∼ 66°, which produces masses of 1.88 and 1.85 M⊙ for the components. A comparison with evolutionary tracks …
Thin-Shell Mixing In Radiative Wind-Shocks And The L-X Similar To L-Bol Scaling Of O-Star X-Rays, 2013 Swarthmore College
Thin-Shell Mixing In Radiative Wind-Shocks And The L-X Similar To L-Bol Scaling Of O-Star X-Rays, S. P. Owocki, J. O. Sundqvist, David H. Cohen, K. G. Gayley
Physics & Astronomy Faculty Works
X-ray satellites since Einstein have empirically established that the X-ray luminosity from single O-stars scales linearly with bolometric luminosity, L-x similar to 10(-7)L(bol). But straightforward forms of the most favoured model, in which X-rays arise from instability-generated shocks embedded in the stellar wind, predict a steeper scaling, either with mass-loss rate L-x similar to(M)over dot similar to L-bol(1.7) if the shocks are radiative or with L-x similar to (M)over dot(2) similar to L-bol(3.4) if they are adiabatic. This paper presents a generalized formalism that bridges these radiative versus adiabatic limits in terms of the ratio of the shock cooling length …
Faraday Rotation Distributions From Stellar Magnetism In Wind-Blown Bubbles., 2013 East Tennessee State University
Faraday Rotation Distributions From Stellar Magnetism In Wind-Blown Bubbles., Richard Ignace, N. Pingel
ETSU Faculty Works
Faraday rotation is a valuable tool for detecting magnetic fields. Here, the technique is considered in relation to wind-blown bubbles. In the context of spherical winds with azimuthal or split monopole stellar magnetic field geometries, we derive maps of the distribution of position angle (P.A.) rotation of linearly polarized radiation across projected bubbles. We show that the morphology of maps for split monopole fields are distinct from those produced by the toroidal field topology; however, the toroidal case is the one most likely to be detectable because of its slower decline in field strength with distance from the star. We …
The Opacity Of Spiral Galaxy Disks : Ix. Dust And Gas Surface Densities., 2013 University of Louisville
The Opacity Of Spiral Galaxy Disks : Ix. Dust And Gas Surface Densities., Benne W. Holwerda, R. J. Allen, W. J. G. De Blok, A. Bouchard, R. A. Gonzalez-Lopezlira, P. C. Van Der Kruit, A. Leroy
Faculty Scholarship
Our aim is to explore the relation between gas, atomic and molecular, and dust in spiral galaxies. Gas surface densities are from atomic hydrogen and CO line emission maps. To estimate the dust content, we use the disk opacity as inferred from the number of distant galaxies identified in twelve HST/WFPC2 fields of ten nearby spiral galaxies. The observed number of distant galaxies is calibrated for source confusion and crowding with artificial galaxy counts and here we verify our results with sub-mm surface brightnesses from archival Herschel-SPIRE data. We find that the opacity of the spiral disk does not correlate …
Faraday Rotation Distributions From Stellar Magnetism In Wind-Blown Bubbles., 2013 East Tennessee State University
Faraday Rotation Distributions From Stellar Magnetism In Wind-Blown Bubbles., R. Ignace, N. M. Pingel
Richard Ignace
Faraday rotation is a valuable tool for detecting magnetic fields. Here, the technique is considered in relation to wind-blown bubbles. In the context of spherical winds with azimuthal or split monopole stellar magnetic field geometries, we derive maps of the distribution of position angle (P.A.) rotation of linearly polarized radiation across projected bubbles. We show that the morphology of maps for split monopole fields are distinct from those produced by the toroidal field topology; however, the toroidal case is the one most likely to be detectable because of its slower decline in field strength with distance from the star. We …
Studies Of Ngc 6720 With Calibrated Hst/Wfc3 Emission-Line Filter Images. I. Structure And Evolution, 2013 Vanderbilt University
Studies Of Ngc 6720 With Calibrated Hst/Wfc3 Emission-Line Filter Images. I. Structure And Evolution, C. R. O'Dell, Gary J. Ferland, W. J. Henney, M. Peimbert
Physics and Astronomy Faculty Publications
We have performed a detailed analysis of the Ring Nebula (NGC 6720) using Hubble Space Telescope WFC3 images and derived a new three-dimensional model. Existing high spectral resolution spectra played an important supplementary role in our modeling. It is shown that the Main Ring of the nebula is an ionization-bounded irregular non-symmetric disk with a central cavity and perpendicular extended lobes pointed almost toward the observer. The faint outer halos are determined to be fossil radiation, i.e., radiation from gas ionized in an earlier stage of the nebula when it was not ionization bounded. The narrowband WFC3 filters that isolate …