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Articles 5161 - 5190 of 8859

Full-Text Articles in Astrophysics and Astronomy

The 72-H Webt Microvariability Observation Of Blazar S5 0716+714 In 2009, G Bhatta, Stéphane Vennes Jan 2013

The 72-H Webt Microvariability Observation Of Blazar S5 0716+714 In 2009, G Bhatta, Stéphane Vennes

Aerospace, Physics, and Space Science Faculty Publications

Context. The international Whole Earth Blazar Telescope (WEBT) consortium planned and carried out three days of intensive micro-variability observations of S5 0716+714 from February 22, 2009 to February 25, 2009. This object was chosen due to its bright apparent magnitude range, its high declination, and its very large duty cycle for micro-variations. Aims. We report here on the long continuous optical micro-variability light curve of 0716+714 obtained during the multi-site observing campaign during which the Blazar showed almost constant variability over a 0.5 mag range. The resulting light curve is presented here for the first time. Observations from participating observatories …

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Compositional Diversity In The Atmospheres Of Hot Neptunes, With Application To Gj 436b, J. I. Moses, M. R. Line, Channon Visscher, M. R. Richardson, N. Nettleman, J. J. Fortney, T. S. Barman, K. B. Stevenson, N. Madhusudhan Jan 2013

Compositional Diversity In The Atmospheres Of Hot Neptunes, With Application To Gj 436b, J. I. Moses, M. R. Line, Channon Visscher, M. R. Richardson, N. Nettleman, J. J. Fortney, T. S. Barman, K. B. Stevenson, N. Madhusudhan

Faculty Work Comprehensive List

Neptune-sized extrasolar planets that orbit relatively close to their host stars—often called "hot Neptunes"—are common within the known population of exoplanets and planetary candidates. Similar to our own Uranus and Neptune, inefficient accretion of nebular gas is expected produce hot Neptunes whose masses are dominated by elements heavier than hydrogen and helium. At high atmospheric metallicities of 10-10,000 times solar, hot Neptunes will exhibit an interesting continuum of atmospheric compositions, ranging from more Neptune-like, H2-dominated atmospheres to more Venus-like, CO2-dominated atmospheres. We explore the predicted equilibrium and disequilibrium chemistry of generic hot Neptunes and find that …

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Chemistry Of Impact-Generated Silicate Melt-Vapor Debris Disks, Channon Visscher, Bruce Fegley Jr. Jan 2013

Chemistry Of Impact-Generated Silicate Melt-Vapor Debris Disks, Channon Visscher, Bruce Fegley Jr.

Faculty Work Comprehensive List

In the giant impact theory for lunar origin, the Moon forms from material ejected by the impact into an Earth-orbiting disk. Here we report the initial results from a silicate melt-vapor equilibrium chemistry model for such impact-generated planetary debris disks. In order to simulate the chemical behavior of a two-phase (melt+vapor) disk, we calculate the temperature-dependent pressure and chemical composition of vapor in equilibrium with molten silicate from 2000 to 4000 K. We consider the elements O, Na, K, Fe, Si, Mg, Ca, Al, Ti, and Zn for a range of bulk silicate compositions (Earth, Moon, Mars, eucrite parent body, …

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Unsolved Problems In Special And General Relativity, Florentin Smarandache, Fu Yuhua, Zhao Fengjuan Jan 2013

Unsolved Problems In Special And General Relativity, Florentin Smarandache, Fu Yuhua, Zhao Fengjuan

Branch Mathematics and Statistics Faculty and Staff Publications

This book includes 21 papers written by 23 authors and co-authors. All papers included herein are produced by scholars from People’s Republic of China, except two papers written by Prof. L. Sapogin, V. A. Dzhanibekov, Yu. A. Ryabov from Russia, and by Prof. Florentin Smarandache from USA. The editors hope that all these papers will contribute to the advance of scholarly research on several aspects of Special and General Relativity. This book is suitable for students and scholars interested in studies on physics. The first paper is written by Hua Di. He writes that Einstein’s general theory of relativity cannot …

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Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell Jan 2013

Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell

Dartmouth Scholarship

Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.

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Single Spin Asymmetry An In Polarized Proton–Proton Elastic Scattering At √S = 200 Gev, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, J. Alford, C. D. Anson, D. Arkhipkin, E. Aschenauer, S. Bültmann, I. Koralt, D. Plyku Jan 2013

Single Spin Asymmetry An In Polarized Proton–Proton Elastic Scattering At √S = 200 Gev, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, J. Alford, C. D. Anson, D. Arkhipkin, E. Aschenauer, S. Bültmann, I. Koralt, D. Plyku

Physics Faculty Publications

We report a high precision measurement of the transverse single spin asymmetry AN at the center of mass energy √s = 200 GeV in elastic proton–proton scattering by the STAR experiment at RHIC. The AN was measured in the four-momentum transfer squared t range 0.003 ⩽ | t | ⩽ 0.035 ( GeV / c ) 2 , the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of AN and its t-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the …

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Practical Approach To Cosmological Perturbations In Modified Gravity, Alessandra Silvestri, Levon Pogosian, Roman V. Buniy Jan 2013

Practical Approach To Cosmological Perturbations In Modified Gravity, Alessandra Silvestri, Levon Pogosian, Roman V. Buniy

Mathematics, Physics, and Computer Science Faculty Articles and Research

The next generation of large scale surveys will not only measure cosmological parameters within the framework of general relativity, but will also allow for precision tests of the framework itself. At the order of linear perturbations, departures from the growth in the standard cosmological model can be quantified in terms of two functions of time and Fourier number k. We argue that in local theories of gravity, in the quasistatic approximation, these functions must be ratios of polynomials in k, with the numerator of one function being equal to the denominator of the other. Moreover, the polynomials are even and …

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Illuminating The Darkest Gamma-Ray Bursts With Radio Observations, B.A. Zauderer, E. Berger, R. Margutti, A.J. Levan, F. Olivares E., D.A. Perley, W. Fong, A. Horesh, Adria Updike, J. Greiner, N.R. Tanvir, T. Laskar, R. Chornock, A.M. Soderberg, K.M. Menten, E. Nakar, J. Carpenter, P. Chandra, A.J. Castro-Tirado, M. Bremer, J. Gorosabel, S. Guziy, D. P´Erez-Ram´Irez, J.M. Winters Jan 2013

Illuminating The Darkest Gamma-Ray Bursts With Radio Observations, B.A. Zauderer, E. Berger, R. Margutti, A.J. Levan, F. Olivares E., D.A. Perley, W. Fong, A. Horesh, Adria Updike, J. Greiner, N.R. Tanvir, T. Laskar, R. Chornock, A.M. Soderberg, K.M. Menten, E. Nakar, J. Carpenter, P. Chandra, A.J. Castro-Tirado, M. Bremer, J. Gorosabel, S. Guziy, D. P´Erez-Ram´Irez, J.M. Winters

Arts & Sciences Faculty Publications

No abstract provided.

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Challenges For Λcdm And Mond, Stacy S. Mcgaugh Jan 2013

Challenges For Λcdm And Mond, Stacy S. Mcgaugh

Faculty Scholarship

The Universe on large scales is well described by the ΛCDM cosmological model. There however remain some heavy clouds on our global understanding, especially on galaxy scales, which we review here. While some of these clouds might perhaps disappear through small compensatory adjustments of the model, such as changing the mass of the dark matter particles or accounting better for baryonic physics, others should rather be taken as strong indications that the physics of the dark sector is, at the very least, much richer and complex than currently assumed, and that our understanding of gravity and dynamics might also be …

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Bayesian Inference Of Polarized Cosmic Microwave Background Power Spectra From Interferometric Data, Ata Karakci, P. M. Sutter, Le Zhang, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt Jan 2013

Bayesian Inference Of Polarized Cosmic Microwave Background Power Spectra From Interferometric Data, Ata Karakci, P. M. Sutter, Le Zhang, Emory F. Bunn, Andrei Korotkov, Peter Timbie, Gregory S. Tucker, Benjamin D. Wandelt

Physics Faculty Publications

Detection of B-mode polarization of the cosmic microwave background (CMB) radiation is one of the frontiers of observational cosmology. Because they are an order of magnitude fainter than E-modes, it is quite a challenge to detect B-modes. Having more manageable systematics, interferometers prove to have a substantial advantage over imagers in detecting such faint signals. Here, we present a method for Bayesian inference of power spectra and signal reconstruction from interferometric data of the CMB polarization signal by using the technique of Gibbs sampling. We demonstrate the validity of the method in the flat-sky approximation for a simulation of an …

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A Study In Merger Induced Galaxy Evolution Through Post-Starburst Systems, Zachary Dean Griffith Jan 2013

A Study In Merger Induced Galaxy Evolution Through Post-Starburst Systems, Zachary Dean Griffith

Honors Program Theses

We discuss an optical study of a triple galaxy system at a redshift of 0.06. In optical images from Data Release 7 of the Sloan Digital Sky Survey (SDSS), the system consists of a close pair plus another galaxy at a projected distance of 35 kpc. Tidal features extending at least 30 kpc are visible to the southeast of both the galaxy pair and the third member of the system, suggesting significant interaction. One of the the pair and the more isolated galaxy are low-luminosity radio sources. The lone galaxy appears extended in a radio map from the FIRST survey. …

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Galaxy Zoo : A Catalog Of Overlapping Galaxy Pairs For Dust Studies., William C. Keel, Anna M. Manning, Benne W. Holwerda, Massimo Mezzoprete, Chris J. Lintott, Kevin Schawinski, Pamela Gay, Karen L. Masters Jan 2013

Galaxy Zoo : A Catalog Of Overlapping Galaxy Pairs For Dust Studies., William C. Keel, Anna M. Manning, Benne W. Holwerda, Massimo Mezzoprete, Chris J. Lintott, Kevin Schawinski, Pamela Gay, Karen L. Masters

Faculty and Staff Scholarship

Analysis of galaxies with overlapping images offers a direct way to probe the distribution of dust extinction and its effects on the background light. We present a catalog of 1990 such galaxy pairs selected from the Sloan Digital Sky Survey (SDSS) by volunteers of the Galaxy Zoo project. We highlight subsamples which are particularly useful for retrieving such properties of the dust distribution as UV extinction, the extent perpendicular to the disk plane, and extinction in the inner parts of disks. The sample spans wide ranges of morphology and surface brightness, opening up the possibility of using this technique to …

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Effective Field Theory Approach To Gravitationally Induced Decoherence, M. P. Blencowe Jan 2013

Effective Field Theory Approach To Gravitationally Induced Decoherence, M. P. Blencowe

Dartmouth Scholarship

Adopting the viewpoint that the standard perturbative quantization of general relativity provides an effective description of quantum gravity that is valid at ordinary energies, we show that gravity as an environment induces the rapid decoherence of stationary matter superposition states when the energy differences in the superposition exceed the Planck energy scale.

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Book Review: Weird Worlds: Bizarre Bodies Of The Solar System And Beyond, T. D. Oswalt Jan 2013

Book Review: Weird Worlds: Bizarre Bodies Of The Solar System And Beyond, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Weird Worlds : Bizarre Bodies of the Solar System and Beyond by David A. J. Seargent. Springer, 2013 309p, 1461470633 $34.95, 9781461470632 $34.95.

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Heteroclinic And Homoclinic Connections Between The Sun-Earth Triangular Points And Quasi-Satellite Orbits For Solar Observations, Pedro J. Llanos, Gerald R. Hintz, Martin W. Lo, James K. Miller Jan 2013

Heteroclinic And Homoclinic Connections Between The Sun-Earth Triangular Points And Quasi-Satellite Orbits For Solar Observations, Pedro J. Llanos, Gerald R. Hintz, Martin W. Lo, James K. Miller

Publications

Investigation of new orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space weather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to monitor solar activity such as a sub-solar orbit or quasi-satellite orbit and short and long heteroclinic and homoclinic connections between the triangular points L4 and L5 and the collinear point L3 of the CRTBP (circular restricted three-body problem) in the Sun-Earth system. These trajectories could serve as channels through where material can be transported from L5 to L3 by performing small maneuvers at the departure of the Trojan orbit. …

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Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics – Ii. Clues To The Origins Of S0 Galaxies, A. Cortesi, M. R. Merrifield, L. Coccato, M. Arnaboldi, O. Gerhard, Aaron J. Romanowsky, N. G. Douglass, K. Kuiijken, M. Capaccioli, K. C. Freeman, K. Saha, A. L. Chies-Santos Jan 2013

Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics – Ii. Clues To The Origins Of S0 Galaxies, A. Cortesi, M. R. Merrifield, L. Coccato, M. Arnaboldi, O. Gerhard, Aaron J. Romanowsky, N. G. Douglass, K. Kuiijken, M. Capaccioli, K. C. Freeman, K. Saha, A. L. Chies-Santos

Faculty Publications

The stellar kinematics of the spheroids and discs of S0 galaxies contain clues to their formation histories. Unfortunately, it is difficult to disentangle the two components and to recover their stellar kinematics in the faint outer parts of the galaxies using conventional absorption line spectroscopy. This paper therefore presents the stellar kinematics of six S0 galaxies derived from observations of planetary nebulae, obtained using the Planetary Nebula Spectrograph. To separate the kinematics of the two components, we use a maximum-likelihood method that combines the discrete kinematic data with a photometric component decomposition. The results of this analysis reveal that: the …

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The Densest Galaxy, J. Strader, A. C. Seth, J. P. Brodie, D. A. Forbes, G. Fabbiano, Aaron J. Romanowsky, C. Conroy, N. Caldwell, V. Pota, C. Usher, J. A. Arnold Jan 2013

The Densest Galaxy, J. Strader, A. C. Seth, J. P. Brodie, D. A. Forbes, G. Fabbiano, Aaron J. Romanowsky, C. Conroy, N. Caldwell, V. Pota, C. Usher, J. A. Arnold

Faculty Publications

We report the discovery of a remarkable ultra-compact dwarf galaxy around the massive Virgo elliptical galaxy NGC 4649 (M60), which we call M60-UCD1. With a dynamical mass of 2.0 × 108 M ☉ but a half-light radius of only ~24 pc, M60-UCD1 is more massive than any ultra-compact dwarfs of comparable size, and is arguably the densest galaxy known in the local universe. It has a two-component structure well fit by a sum of Sérsic functions, with an elliptical, compact (rh = 14 pc; n ~ 3.3) inner component and a round, exponential, extended (rh = 49 pc) outer component. …

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The Paucity Of Globular Clusters Around The Field Elliptical Ngc 7507, J. P. Caso, T. Richtler, L. P. Bassino, R. Salinas, R. R. Lane, Aaron J. Romanowsky Jan 2013

The Paucity Of Globular Clusters Around The Field Elliptical Ngc 7507, J. P. Caso, T. Richtler, L. P. Bassino, R. Salinas, R. R. Lane, Aaron J. Romanowsky

Faculty Publications

There is strong evidence that globular cluster systems (GCSs) of massive galaxies are largely assembled by infall/accretion processes. Therefore, we expect the GCSs of isolated elliptical galaxies to be poor. Alhough not completely isolated, NGC 7507 is a massive field elliptical galaxy with an apparently very low dark matter content. Aims: We determine the richness, the colour distribution, and the structural properties of the GCS of NGC 7507. Methods: We perform wide-field Washington photometry with data obtained with the MOSAIC II camera at the 4m-Blanco telescope, CTIO. Results: The GCS is very poor with S_N ~ 0.6. We identify three …

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Angular Momentum And Galaxy Formation Revisited: Effects Of Variable Mass-To-Light Ratios, S. M. Fall, Aaron J. Romanowsky Jan 2013

Angular Momentum And Galaxy Formation Revisited: Effects Of Variable Mass-To-Light Ratios, S. M. Fall, Aaron J. Romanowsky

Faculty Publications

We rederive the relation between the specific angular momentum j sstarf and the mass M sstarf of the stellar matter in galaxies of different morphological types. This is a revision of the j sstarf-M sstarf diagram presented in our recent comprehensive study of galactic angular momentum. In that work, we estimated j sstarf from kinematic and photometric data that extended to large radii and M sstarf from near-infrared luminosities LK with an assumed universal mass-to-light ratio M sstarf/LK . However, recent stellar population models show large variations in M sstarf/LK correlated with B – V color. In the present work, …

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Parameter Estimation For Compact Binary Coalescence Signals With The First Generation Gravitational-Wave Detector Network, J. Aasi, J. Abadie, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Robert Stone, Cristina V. Torres Jan 2013

Parameter Estimation For Compact Binary Coalescence Signals With The First Generation Gravitational-Wave Detector Network, J. Aasi, J. Abadie, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Robert Stone, Cristina V. Torres

Physics & Astronomy Faculty Publications

Compact binary systems with neutron stars or black holes are one of the most promising sources for ground-based gravitational-wave detectors. Gravitational radiation encodes rich information about source physics; thus parameter estimation and model selection are crucial analysis steps for any detection candidate events. Detailed models of the anticipated waveforms enable inference on several parameters, such as component masses, spins, sky location and distance, that are essential for new astrophysical studies of these sources. However, accurate measurements of these parameters and discrimination of models describing the underlying physics are complicated by artifacts in the data, uncertainties in the waveform models and …

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Study Of Dynamic Features Of Highly Energetic Reactions By Dsc And High-Speed Temperature Scanner (Hsts), Mkhitar Hobosyan, Kh. G. Kirakosyan, S. L. Kharatyan, Karen S. Martirosyan Jan 2013

Study Of Dynamic Features Of Highly Energetic Reactions By Dsc And High-Speed Temperature Scanner (Hsts), Mkhitar Hobosyan, Kh. G. Kirakosyan, S. L. Kharatyan, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The dynamic features of Al2O3 - polytetrafluoroethylene (PTFE) and Al - PTFE reactions in non-isothermal conditions are presented. The Differential Scanning Calorimetry (DSC) and High-Speed Temperature Scanner (HSTS) were used to characterize the Al2O3/Al – PTFE reactions at different heating rates. The study shows that the HSTS instrument can give more information about the reaction mechanism and kinetics than the conventional DSC measurements. In this work we show that high heating rates may reveal exothermic reaction between Al2O3 and PTFE that were previously unidentified. The PTFE can potentially remove the oxide layer from aluminum in the initial period of the …

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Analysis Of Mathematical Descriptions Of Gravitational Microlensing, Sarah Michelle Pearce Jan 2013

Analysis Of Mathematical Descriptions Of Gravitational Microlensing, Sarah Michelle Pearce

Honors Program Theses

This thesis will provide an analysis of some aspects of gravitational microlensing and the quantitative descriptions used to model the astrophysical systems involved. One aspect of the mathematical description of micro lensing events that is investigated in this thesis is the evolution of micro lensing equations from the formalism of general relativity. The derivation of these equations from those governing general relativity and the bending of light rays in geometric optics is explicitly determined. The relationship between the equations used to model events and the light curves produced is investigated. The effect of degeneracies in the mathematical equations used to …

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Visualizing And Understanding Tectonism And Volcanism On Earth And Other Terrestrial Bodies, Mladen M. Dordevic Jan 2013

Visualizing And Understanding Tectonism And Volcanism On Earth And Other Terrestrial Bodies, Mladen M. Dordevic

Physics Theses & Dissertations

This dissertation presents new methods of visualizing, teaching, assessing, modeling, and understanding tectonics on Earth and other celestial bodies. Tectonics is the study of planetary lithospheres and includes impact, plate, plume, cryo- and gravitational mechanisms. This dissertation is concerned with plate tectonics and plate/mantle plume interactions. Plate tectonics describes the mainly horizontal motion of lithospheric plates over the asthenosphere. Lithosphere is created at ridges and consumed at subduction zones. In addition to the plate tectonic system, mantle plumes also contribute to mass motions in the subsurface Earth. Both plate tectonics and plume upwelling processes help shape the present form of …

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Fundamental Limits Of Detection In The Near And Mid Infrared, Nathan Lenssen Jan 2013

Fundamental Limits Of Detection In The Near And Mid Infrared, Nathan Lenssen

CMC Senior Theses

The construction of the James Webb Space Telescope has brought attention to infrared astronomy and cosmology. The potential information about our universe to be gained by this mission and future infrared telescopes is staggering, but infrared observation faces many obstacles. These telescopes face large amounts of noise by many phenomena, from emission off of the mirrors to the cosmic infrared background. Infrared telescopes need to be designed in such a way that noise is minimized to achieve sufficient signal to noise ratio on high redshift objects. We will investigate current and planned space and ground based telescopes, model the noise …

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Testing Diagnostics Of Nuclear Activity And Star Formation In Galaxies At Z > 1, Jonathan R. Trump, Nicholas P. Konidaris, Guillermo Barro, David C. Koo, Dale D. Kocevski, Stéphanie Juneau, Benjamin J. Weiner, S. M. Faber, Ian S. Mclean, Renbin Yan, Pablo G. Pérez-González, Victor Villar Dec 2012

Testing Diagnostics Of Nuclear Activity And Star Formation In Galaxies At Z > 1, Jonathan R. Trump, Nicholas P. Konidaris, Guillermo Barro, David C. Koo, Dale D. Kocevski, Stéphanie Juneau, Benjamin J. Weiner, S. M. Faber, Ian S. Mclean, Renbin Yan, Pablo G. Pérez-González, Victor Villar

Physics and Astronomy Faculty Publications

We present some of the first science data with the new Keck/MOSFIRE instrument to test the effectiveness of different AGN/SF diagnostics at z ~ 1.5. MOSFIRE spectra were obtained in three H-band multi-slit masks in the GOODS-S field, resulting in 2 hr exposures of 36 emission-line galaxies. We compare X-ray data with the traditional emission-line ratio diagnostics and the alternative mass-excitation and color-excitation diagrams, combining new MOSFIRE infrared data with previous HST/WFC3 infrared spectra (from the 3D-HST survey) and multiwavelength photometry. We demonstrate that a high [O III]/Hβ ratio is insufficient as an active galactic nucleus (AGN) indicator …

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The Central Molecular Gas Structure In Liners With Low-Luminosity Active Galactic Nuclei: Evidence For Gradual Disappearance Of The Torus, F. Müller-Sánchez, M. A. Prieto, M. Mezcua, R. I. Davies, M. A. Malkan, Moshe Elitzur Dec 2012

The Central Molecular Gas Structure In Liners With Low-Luminosity Active Galactic Nuclei: Evidence For Gradual Disappearance Of The Torus, F. Müller-Sánchez, M. A. Prieto, M. Mezcua, R. I. Davies, M. A. Malkan, Moshe Elitzur

Physics and Astronomy Faculty Publications

We present observations of the molecular gas in the nuclear environment of three prototypical low-luminosity active galactic nuclei (LLAGNs), based on VLT/SINFONI AO-assisted integral-field spectroscopy of H2 1-0 S(1) emission at angular resolutions of ~0.''17. On scales of 50-150 pc, the spatial distribution and kinematics of the molecular gas are consistent with a rotating thin disk, where the ratio of rotation (V) to dispersion (σ) exceeds unity. However, in the central 50 pc, the observations reveal a geometrically and optically thick structure of molecular gas (V/σ < 1 and N H > 1023 cm–2 …

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Kelt-1b: A Strongly Irradiated, Highly Inflated, Short Period, 27 Jupiter-Mass Companion Transiting A Mid-F Star, R. J. Siverd, T. G. Beatty, J. Pepper, J. D. Eastman, K. Collins, A. Bieryla, D. W. Latham, L. A. Buchhave, Eric L.N. Jensen, J. R. Crepp, R. Street, K. G. Stassun, B. S. Gaudi, P. Berlind, M. L. Calkins, D. L. Depoy, G. A. Esquerdo, B. J. Fulton, G. Fürész, J. C. Geary, A. Gould, L. Hebb, J. F. Kielkopf, J. L. Marshall, R. Pogge, K. Z. Stanek, R. P. Stefanik, A. H. Szentgyorgyi, M. Trueblood, P. Trueblood, A. M. Stutz, J. L. Van Saders Dec 2012

Kelt-1b: A Strongly Irradiated, Highly Inflated, Short Period, 27 Jupiter-Mass Companion Transiting A Mid-F Star, R. J. Siverd, T. G. Beatty, J. Pepper, J. D. Eastman, K. Collins, A. Bieryla, D. W. Latham, L. A. Buchhave, Eric L.N. Jensen, J. R. Crepp, R. Street, K. G. Stassun, B. S. Gaudi, P. Berlind, M. L. Calkins, D. L. Depoy, G. A. Esquerdo, B. J. Fulton, G. Fürész, J. C. Geary, A. Gould, L. Hebb, J. F. Kielkopf, J. L. Marshall, R. Pogge, K. Z. Stanek, R. P. Stefanik, A. H. Szentgyorgyi, M. Trueblood, P. Trueblood, A. M. Stutz, J. L. Van Saders

Physics & Astronomy Faculty Works

We present the discovery of KELT-1b, the first transiting low-mass companion from the wide-field Kilodegree Extremely Little Telescope-North (KELT-North) transit survey. A joint analysis of the spectroscopic, radial velocity, and photometric data indicates that the V = 10.7 primary is a mildly evolved mid-F star with T-eff = 6516 +/- 49 K, log g = 4.228(-0.021)(+0.014), and [Fe/H] = 0.052 +/- 0.079, with an inferred mass M* = 1.335 +/- 0.063M(circle dot) and radius R* = 1.471(-0.035)(+0.045) R-circle dot. The companion is a low-mass brown dwarf or a super-massive planet with mass M-P = 27.38 +/- 0.93 M-Jup and radius …

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Tuning Of Alternative Splicing - Switch From Proto-Oncogene To Tumor Suppressor, Aleksandra Shchelkunova, Boris Ermolinsky, Meghan Boyle, Ivan Mendez, Michael Lehker, Karen S. Martirosyan, Alexander V. Kazansky Dec 2012

Tuning Of Alternative Splicing - Switch From Proto-Oncogene To Tumor Suppressor, Aleksandra Shchelkunova, Boris Ermolinsky, Meghan Boyle, Ivan Mendez, Michael Lehker, Karen S. Martirosyan, Alexander V. Kazansky

Physics & Astronomy Faculty Publications

STAT5B, a specific member of the ST AT family, is intimately associated with prostate tumor progression. While the full form of STAT5B is thought to promote tumor progression, a naturally occurring truncated isoform acts as a tumor suppressor. We previously demonstrated that truncated STAT5 is generated by insertion of an alternatively spliced exon and results in the introduction of an early termination codon. Present approaches targeting ST AT proteins based on inhibition of functional domains of STAT's, such as DNA-binding, cooperative binding (protein-protein interaction), dimerization and phosphorylation will halt the action of the entire gene, both the proto-oncogenic and tumor …

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Investigation Of Low-Stress Silicon Nitride As A Replacement Material For Beryllium X-Ray Windows, David B. Brough Dec 2012

Investigation Of Low-Stress Silicon Nitride As A Replacement Material For Beryllium X-Ray Windows, David B. Brough

Theses and Dissertations

The material properties of low stress silicon nitride make it a possible replacement material for beryllium in X-ray windows. In this study, X-ray windows made of LPCVD deposited low stress silicon nitride are fabricated and characterized. The Young's modulus of the LPCVD low stress silicon nitride are characterized and found to be 226±23 GPa. The residual stress is characterized using two different methods and is found to be 127±25 MPa and 141±0.28 MPa. Two support structure geometries for the low stress silicon nitride X-ray windows are used. X-ray windows with thicknesses of 100 nm and 200 nm are suspended on …

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Thin Films Of Carbon Nanotubes And Nanotube/Polymer Composites, Anthony D. Willey Dec 2012

Thin Films Of Carbon Nanotubes And Nanotube/Polymer Composites, Anthony D. Willey

Theses and Dissertations

A method is described for ultrasonically spraying thin films of carbon nanotubes that have been suspended in organic solvents. Nanotubes were sonicated in N-Methyl-2-pyrrolidone or N-Cyclohexyl-2-pyrrolidone and then sprayed onto a heated substrate using an ultrasonic spray nozzle. The solvent quickly evaporated, leaving a thin film of randomly oriented nanotubes. Film thickness was controlled by the spray time and ranged between 200-500 nm, with RMS roughness of about 40 nm. Also described is a method for creating thin (300 nm) conductive freestanding nanotube/polymer composite films by infiltrating sprayed nanotube films with polyimide.

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