Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris,
2012
University of Texas at El Paso
Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris, Jose Humberto Garcia
Open Access Theses & Dissertations
The discovery of water on the Moon raises the possibility that lava-water, or phreatomagmatic, interactions have occurred on the lunar surface in the past. Such interactions may have formed pseudocraters, crater-like landforms that result from steam explosions that occur when lava flows come in contact with surface or near-surface water or ice. We present a study of Mare Frigoris, a volcanic plain just north of the Mare Imbrium impact basin on the Moon. Clusters of irregular, circular features on the basaltic lava flows in this area resemble pseudocrater fields in Iceland, and they are located in a region with inferred …
The Agile Monitoring Of Cygnus X-3: Transient Gamma-Ray Emission And Spectral Constraints,
2012
INAF/IAPS Rome
The Agile Monitoring Of Cygnus X-3: Transient Gamma-Ray Emission And Spectral Constraints, Giovanni Piano, Diana Carina Hannikainen
Aerospace, Physics, and Space Science Faculty Publications
We present the AGILE-GRID (Astro-rivelatore Gamma a Immagini LEggero – Gamma-Ray Imaging Detector) monitoring of Cygnus X-3, during the period between November 2007 and July 2009. We report here the whole AGILE-GRID monitoring of Cygnus X-3 in the AGILE “pointing” mode data-taking, to confirm that the γ-ray activity coincides with the same repetitive pattern of multiwavelength emission and analyze in depth the overall γ-ray spectrum by assuming both leptonic and hadronic scenarios. Seven intense γ-ray events were detected in this period, with a typical event lasting one or two days. These durations are longer than the likely cooling times of …
The Evolution Of Ultracompact X-Ray Binaries,
2012
Radboud University Nijmegen
The Evolution Of Ultracompact X-Ray Binaries, Lennart M. Van Haaften, Gijs A. Nelemans, Rasmus Voss, Matt A. Wood, Jan Kuijpers
Aerospace, Physics, and Space Science Faculty Publications
Context. Ultracompact X-ray binaries (UCXBs) typically consist of a white dwarf donor and a neutron star or black hole accretor. The evolution of UCXBs and very low mass ratio binaries in general is poorly understood. In particular, the dynamical behavior of an accretion disk extending to a large radius (relative to the orbit) is unclear. Aims. We investigate the evolution of UCXBs in order to learn for which mass ratios and accretor types these systems can exist, and if they do, what are their orbital and neutron star spin periods, mass transfer rates and evolutionary timescales. Methods. We compute tracks …
A Deep Search For The Host Galaxies Of Gamma-Ray Bursts With No Detected Optical Afterglow,
2012
Thüringer Landessternwarte Tautenburg
A Deep Search For The Host Galaxies Of Gamma-Ray Bursts With No Detected Optical Afterglow, Andrea Rossi, E E. Gonsalves
Aerospace, Physics, and Space Science Faculty Publications
Context. Gamma-ray bursts (GRBs) can provide information about star formation at high redshifts. Even in the absence of a bright optical/near-infrared/radio afterglow, the high detection rate of X-ray afterglows by Swift/XRT and its localization precision of 2–3 arcsec facilitates the identification and the study of GRB host galaxies. Aims. We focus on the search for the host galaxies of 17 bursts with arcsec-sized XRT error circles but no detected long-wavelength afterglow, in spite of their deep and rapid follow-up observations. Three of these events can also be classified as truly dark bursts, i.e., the observed upper limit on the optical …
Agile Detection Of Cygnus X-3 Γ-Ray Active States During The Period Mid-2009/Mid-2010,
2012
Instituto Nazionale di Astrofisica (INAF) - Bologna
Agile Detection Of Cygnus X-3 Γ-Ray Active States During The Period Mid-2009/Mid-2010, A Bulgarelli, Diana C. Hannikainen
Aerospace, Physics, and Space Science Faculty Publications
Context. Cygnus X-3 (Cyg X-3) is a well-known microquasar producing variable emission at all wavelengths. Cyg X-3 is a prominent X-ray binary producing relativistic jets, and studying its high energy emission is crucial for the understanding of the fundamental acceleration processes in accreting compact objects. Aims. Our goal is to study extreme particle acceleration and γ-ray production above 100 MeV during special spectral states of Cyg X-3 usually characterized by a low hard X-ray flux and enhanced soft X-ray states. Methods. We observed Cyg X-3 with the AGILE satellite in extended time intervals from 2009 Jun.–Jul., and 2009 Nov.–2010 Jul. …
International Observational Campaigns Of The Last Two Eclipses In Ee Cephei: 2003 And 2008/9,
2012
Nicolaus Copernicus University of Torun
International Observational Campaigns Of The Last Two Eclipses In Ee Cephei: 2003 And 2008/9, Cezary Galan, Peter Németh
Aerospace, Physics, and Space Science Faculty Publications
Context. EE Cep is an unusual long-period (5.6 yr) eclipsing binary discovered during the mid-twentieth century. It undergoes almost-grey eclipses that vary in terms of both depth and duration at different epochs. The system consists of a Be type star and a dark dusty disk around an invisible companion. EE Cep together with the widely studied ε Aur are the only two known cases of long-period eclipsing binaries with a dark, dusty disk component responsible for periodic obscurations. Aims. Two observational campaigns were carried out during the eclipses of EE Cep in 2003 and 2008/9 to verify whether the eclipsing …
Deviation From Quark Number Scaling Of The Anisotropy Parameter V₂ Of Pions, Kaons, And Protons In Au+Au Collisions At √S Nn=200 Gev,
2012
University of Colorado, Boulder
Deviation From Quark Number Scaling Of The Anisotropy Parameter V₂ Of Pions, Kaons, And Protons In Au+Au Collisions At √S Nn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Marcus Hohlmann, Phenix Collaboration
Aerospace, Physics, and Space Science Faculty Publications
Measurements of the anisotropy parameter v₂ of identified hadrons (pions, kaons, and protons) as a function of centrality, transverse momentum pT, and transverse kinetic energy KET at midrapidity (|η|<0.35) in Au+Au collisions at √sNN=200 GeV are presented. Pions and protons are identified up to pT= 6 GeV/c, and kaons up to pT= 4 GeV/c, by combining information from time-of-flight and aerogel Čerenkov detectors in the PHENIX Experiment. The scaling of v₂ with the number of valence quarks (nq) has been studied in different centrality bins as a function of transverse momentum and transverse kinetic energy. A deviation from previously observed quark-number scaling is observed at large values of KET/nq in noncentral Au+Au collisions (20-60%), but this scaling remains valid in central collisions (0-10%).
Forty-Year Calibrated Record Of Earth-Reflected Radiance From Landsat: A Review,
2012
National Aeronautics and Space Administration, Biospheric Sciences Laboratory
Forty-Year Calibrated Record Of Earth-Reflected Radiance From Landsat: A Review, Brian L. Markham, Dennis L. Helder
United States National Aeronautics and Space Administration: Publications
Sensors on Landsat satellites have been collecting images of the Earth's surface for nearly 40 years. These images have been invaluable for characterizing and detecting changes in the land cover and land use of the world. Although initially conceived as primarily picture generating sensors, even the early sensors were radiometrically calibrated and spectrally characterized prior to launch and incorporated some capabilities to monitor their radiometric calibration once on orbit. Recently, as the focus of studies has shifted to monitoring Earth surface parameters over significant periods of time, serious attention has been focused toward bringing the data from all these sensors …
The Venus "Shell-Over-Star" Hieroglyph And Maya Warfare: An Examination Of The Interpretation Of A Mayan Symbol,
2012
Wayne State University
The Venus "Shell-Over-Star" Hieroglyph And Maya Warfare: An Examination Of The Interpretation Of A Mayan Symbol, Claudia Ann Voit
Wayne State University Theses
For decades, Maya scholars have associated the Mayan ―Shell-Star‖ (also referred to as ―Star-War‖) hieroglyph with Maya warfare. Put forward by scholars such as Floyd Lounsbury and David Kelley, and later advanced by Linda Schele, David Freidel, Ian Graham, Peter Matthews, Anthony Aveni and others, there are now dozens of published articles and chapters relating the hieroglyph to Venus and warfare. Venus is one of the most notable celestial objects outside of the Sun and Moon and was highly visible to the inhabitants of the Maya world. The Dresden Codex (an astronomical almanac) contains important information about the planet Venus, …
The Influence Of Soft Spectral Components On The Structure And Stability Of Warm Absorbers In Active Galactic Nuclei,
2012
IUCAA, India
The Influence Of Soft Spectral Components On The Structure And Stability Of Warm Absorbers In Active Galactic Nuclei, Susmita Chakravorty, Ranjeev Misra, Martin Elvis, Ajit K. Kembhavi, Gary J. Ferland
Physics and Astronomy Faculty Publications
The radiation from the central regions of active galactic nuclei, including that from the accretion disc surrounding the black hole, is likely to peak in the extreme-ultraviolet ∼13–100 eV. However, due to Galactic absorption, we are limited to constrain the physical properties, i.e. the black hole mass and the accretion rate, from what observations we have below ∼10 eV or above ∼100 eV. In this paper, we predict the thermal and ionization states of warm absorbers as a function of the shape of the unobservable continuum. In particular we model an accretion disc at kTin∼ 10 eV and …
Herschel Observations Of Extended Atomic Gas In The Core Of The Perseus Cluster,
2012
Rochester Institute of Technology
Herschel Observations Of Extended Atomic Gas In The Core Of The Perseus Cluster, R. Mittal, J. B. R. Oonk, Gary J. Ferland, A. C. Edge, C. P. O'Dea, S. A. Baum, J. T. Whelan, R. M. Johnstone, F. Combes, P. Salomé, A. C. Fabian, G. R. Tremblay, M. Donahue, Russell H. H.
Physics and Astronomy Faculty Publications
We present Herschel observations of the core of the Perseus cluster of galaxies. Especially intriguing is the network of filaments that surround the brightest cluster galaxy, NGC 1275, previously imaged extensively in Hα and CO. In this work, we report detections of far-infrared (FIR) lines, in particular, [C II] 158, [O I] 63, [N II] 122, [O IB] 145 and [O III] 88 μm, withHerschel. All lines are spatially extended, except [O III], with the [C II] line emission extending up to 25 kpc from the core. [C II] emission is found to be co-spatial with Hα and …
Multiphase Signatures Of Active Galactic Nucleus Feedback In Abell 2597,
2012
European Southern Observatory, Germany
Multiphase Signatures Of Active Galactic Nucleus Feedback In Abell 2597, G. R. Tremblay, C. P. O'Dea, S. A. Baum, T. E. Clarke, C. L. Sarazin, J. N. Bregman, F. Combes, M. Donahue, A. C. Edge, A. C. Fabian, Gary J. Ferland, B. R. Mcnamara, R. Mittal, J. B. R. Oonk, A. C. Quillen, H. R. Russell, J. S. Sanders, P. Salomé, G. M. Voit, R. J. Wilman, M. W. Wise
Physics and Astronomy Faculty Publications
We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool-core cluster Abell 2597 (z= 0.0821). The data reveal an extensive kpc-scale X-ray cavity network as well as a 15-kpc filament of soft-excess gas exhibiting strong spatial correlation with archival Very Large Array radio data. In addition to several possible scenarios, multiwavelength evidence may suggest that the filament is associated with multiphase (103–107 K) gas that has been entrained and dredged-up by the propagating radio source. Stemming from a full spectral analysis, we also present profiles and 2D spectral maps of …
Thermal Effects In The Input Optics Of The Enhanced Laser Interferometer Gravitational-Wave Observatory Interferometers,
2012
The University of Texas Rio Grande Valley
Thermal Effects In The Input Optics Of The Enhanced Laser Interferometer Gravitational-Wave Observatory Interferometers, K. L. Dooley, M. A. Arain, D. Fieldbaum, Volker Quetschke
Physics & Astronomy Faculty Publications
We present the design and performance of the LIGO Input Optics subsystem as implemented for the sixth science run of the LIGO interferometers. The Initial LIGO Input Optics experienced thermal side effects when operating with 7 W input power. We designed, built, and implemented improved versions of the Input Optics for Enhanced LIGO, an incremental upgrade to the Initial LIGO interferometers, designed to run with 30 W input power. At four times the power of Initial LIGO, the Enhanced LIGO Input Optics demonstrated improved performance including better optical isolation, less thermal drift, minimal thermal lensing, and higher optical efficiency. The …
Table Of Contents,
2012
University of South Carolina
Table Of Contents
Journal of the South Carolina Academy of Science
No abstract provided.
Scas Officers And Council Members 2011 - 2012,
2012
University of South Carolina
Scas Officers And Council Members 2011 - 2012
Journal of the South Carolina Academy of Science
No abstract provided.
Stellar Astrophysics With Undergraduate Students,
2012
University of South Carolina
Stellar Astrophysics With Undergraduate Students, Saul J. Adelman
Journal of the South Carolina Academy of Science
No abstract provided.
The Allen Telescope Array Search For Electrostatic Discharges On Mars,
2012
University of California, Berkley
The Allen Telescope Array Search For Electrostatic Discharges On Mars, Marin M. Anderson, Andrew P.V. Siemion, William C. Barott, Geoffery C. Bower, Gregory T. Delory, Imke De Pater, Dan Werthimer
Department of Electrical Engineering and Computer Science - Daytona Beach
The Allen Telescope Array was used to monitor Mars between 2010 March 9 and June 2, over a total of approximately 30 hr, for radio emission indicative of electrostatic discharge. The search was motivated by the report from Ruf et al. of the detection of non-thermal microwave radiation from Mars characterized by peaks in the power spectrum of the kurtosis, or kurtstrum, at 10 Hz, coinciding with a large dust storm event on 2006 June 8. For these observations, we developed a wideband signal processor at the Center for Astronomy Signal Processing and Electronics Research. This 1024 channel spectrometer calculates …
Interacting Dark Energy Models And The Cosmic Coincidence Problem,
2012
Arkansas Tech University
Interacting Dark Energy Models And The Cosmic Coincidence Problem, H. Shojaei, C. Smith, D. Waters
Journal of the Arkansas Academy of Science
Interacting dark energy models have been employed to study the behavior of dark energy and matter in the presence of an interaction between the two. One of the successful aspects of these models is how they explain the cosmic coincidence problem. In this work we consider a specific interaction to study the behavior of dark energy and matter through the history of evolution.
Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations,
2012
University of Texas at El Paso
Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations, Jaclyn Danielle Clark
Open Access Theses & Dissertations
Many small, lobate scarps, interpreted to be the surface traces of thrust faults, have been found all over Earth's moon by previous researchers. Fault dynamical calculations, assuming an initially completely molten Moon, have shown that these scarps can form due to compressional stresses that accumulate over time as the result of large-scale contraction of the Moon as it cooled. With high-resolution images from the Lunar Reconnaissance Orbiter Camera (LROC), previously undetected lobate scarps can be found globally and viewed at high resolution. By investigating these fault scarps, we can determine better constraints on the amount of crustal shortening and improve …
A Reverberation Lag For The High-Ionization Component Of The Broad-Line Region In The Narrow-Line Seyfert 1 Mrk 335,
2012
The Ohio State University
A Reverberation Lag For The High-Ionization Component Of The Broad-Line Region In The Narrow-Line Seyfert 1 Mrk 335, C. J. Grier, B. M. Peterson, R. W. Pogge, K. D. Denney, M. C. Bentz, Paul Martini, S. G. Sergeev, S. Kaspi, Y. Zu, C. S. Kochanek, B. J. Shappee, C. Araya Salvo, T G. Beatty, J. C. Bird, D. J. Bord, G. A. Borman, X. Che, C. Chen
Dartmouth Scholarship
We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335, collected over a 120 day span in the fall of 2010. From these data we measure the lag in the He ii λ 4686 broad emission line relative to the optical continuum to be 2.7 °æ 0.6 days and the lag in the Hβλ 4861 broad emission line to be 13.9 °æ 0.9 days. Combined with the line width, the He ii lag yields a black hole mass MBH = (2. 6 °æ 0. 8) °ø 107M …
