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Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan 2013 University of Arkansas, Fayetteville

Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan

Theses and Dissertations

This study looks at two iron-rich phyllosilicates, which may be present on Mars. The minerals, greenalite and hisingerite, are rich in iron-II and iron-III, respectively. Small samples (~0.40 grams) of each mineral were crushed and heated in a Lindberg Tube Oven for approximately twenty-four hours at temperatures selected to mimic lava flows and impact events. Following heating, each sample was placed in a Fourier Transform Infrared (FT-IR) spectrometer to collect the near- and mid-infrared spectra. The spectra allowed for these terrestrial analogs to be analyzed with regards to how their structure breaks down with increasing temperature. The samples' colors ...


Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha 2013 University of Arkansas, Fayetteville

Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha

Theses and Dissertations

The search for past or present life on Mars is, for now, limited to surface environments. An often neglected surface environment that could have served as an abode for life and could presently preserve evidence of that life is that of rock coatings. Rock coatings are mineral accretions on rock surfaces. On Earth, they are widespread and occur with considerable chemical diversity. There is growing evidence for a biotic role in their formation on Earth, particularly with respect to rock varnish. As a result, rock varnish has become a target of astrobiological interest on Mars, where varnish-like coatings have been ...


Spectral Energy Distributions Of Type 1 Agn In Xmm-Cosmos – Ii. Shape Evolution, Heng Hao, Martin Elvis, Francesca Civano, Gianni Zamorani 2013 Harvard–Smithsonian Center for Astrophysics

Spectral Energy Distributions Of Type 1 Agn In Xmm-Cosmos – Ii. Shape Evolution, Heng Hao, Martin Elvis, Francesca Civano, Gianni Zamorani

Dartmouth Scholarship

The mid-infrared to ultraviolet (0.1 -- 10 μm) spectral energy distribution (SED) shapes of 407 X-ray-selected radio-quiet type 1 AGN in the wide-field ``Cosmic Evolution Survey" (COSMOS) have been studied for signs of evolution. For a sub-sample of 200 radio-quiet quasars with black hole mass estimates and host galaxy corrections, we studied their mean SEDs as a function of a broad range of redshift, bolometric luminosity, black hole mass and Eddington ratio, and compared them with the Elvis et al. (1994, E94) type 1 AGN mean SED. We found that the mean SEDs in each bin are closely similar to ...


The Xmm-Newton Spectrum Of A Candidate Recoiling Supermassive Black Hole: An Elusive Inverted P-Cygni Profile, G. Lanzuisi, F. Civano, S. Marchesi, A. Comastri 2013 Dartmouth College

The Xmm-Newton Spectrum Of A Candidate Recoiling Supermassive Black Hole: An Elusive Inverted P-Cygni Profile, G. Lanzuisi, F. Civano, S. Marchesi, A. Comastri

Dartmouth Scholarship

We present a detailed spectral analysis of new XMM-Newton data of the source CXOC J100043.1+020637, also known as CID-42, detected in the COSMOS survey at z = 0.359. Previous works suggested that CID-42 is a candidate recoiling supermassive black hole (SMBH) showing also an inverted P-Cygni profile in the X-ray spectra at ~6 keV (rest) with an iron emission line plus a redshifted absorption line (detected at 3σ in previous XMM-Newton and Chandra observations). Detailed analysis of the absorption line suggested the presence of ionized material flowing into the black hole at high velocity. In the ...


Molecular Gas In The Circumstellar Environment Of Unusual Evolved Stars, Sarah E. Malek 2013 The University of Western Ontario

Molecular Gas In The Circumstellar Environment Of Unusual Evolved Stars, Sarah E. Malek

Electronic Thesis and Dissertation Repository

As low- and intermediate mass stars (with masses up to 8-9 solar masses) age, they experience a series of evolutionary changes which culminate in the removal of nearly their entire envelope through extensive mass loss. The ejected material cools down, which allows for the formation of molecules and the nucleation of dust grains in the circumstellar environment (CSE) of the star. Much about the properties and composition of the gas and dust in these CSEs is not well understood.

Here, we study the rich CSEs of two unusual evolved stars by analyzing spectral observations in the infrared and using molecular ...


The Study Of Nuclear Structure Of Neutron-Rich 81ge And Its Contribution In The R-Process Via The Neutron Transfer Reaction 80ge(D,P), Sunghoon Ahn 2013 University of Tennessee - Knoxville

The Study Of Nuclear Structure Of Neutron-Rich 81ge And Its Contribution In The R-Process Via The Neutron Transfer Reaction 80ge(D,P), Sunghoon Ahn

Doctoral Dissertations

The study of low-lying levels of nuclei near closed shells not only elucidates the evolution of nuclear shell structure far from stability, but also affects estimates of heavy element nucleosynthesis in supernova explosions. Especially, the properties of the low-lying levels in 81Ge[Germanium 81] are important because the sensitivity study of the r-process pointed out that the properties of the nucleus can affect the final bundance pattern. Also, the spins and parities measurements of the states are essential to understand the shape coexistence in odd-mass N = 49 isotones.

This work describes the study of the odd-mass N = 49 ...


Discovery Of A Massive Young Stellar Object In G10.47+0.27 By Way Of Meta Analysis Of Previously Published Data., Hontas F. Farmer 2013 DePaul University

Discovery Of A Massive Young Stellar Object In G10.47+0.27 By Way Of Meta Analysis Of Previously Published Data., Hontas F. Farmer

Hontas F Farmer

We report the finding of a previously unidentified candidate massive young stellar object at the precise coordinates right ascension 18 08 38.2 and declination -19 51 50 in the region G10.47+0.27. This object was found by correlation of previously published data. At these coordinates the following key tracers of massive star formation are in a compact area; 4.5 micrometer infrared, a Class II methanol maser, two ionized hydrogen regions and three water masers. We also present a physical model of the disk and outflow in this region based on the morphology and kinematics of the ...


Determining The Location Of The Coronal Line Region Within Local Active Galactic Nuclei Using [Fe Vii] Emission Line Properties, Charles Grant Showley 2013 California Polytechnic State University - San Luis Obispo

Determining The Location Of The Coronal Line Region Within Local Active Galactic Nuclei Using [Fe Vii] Emission Line Properties, Charles Grant Showley

Physics

Given a sample of 99 local AGNs, we study the characteristics of the forbidden [Fe VII] coronal line for the purpose of determining the location of the coronal line region (CLR) within the AGN. We calculate the velocity of the clouds emitting [Fe VII] using the width of the [Fe VII] emission lines compared to [O II] emission lines to establish whether the clouds are inflowing or outflowing. We plot the [Fe VII] and [O II] flux ratios against the AGNs' known black hole masses and stellar velocity dispersions in order to see if there are any correlations between them ...


Martian Dune Fields: Aeolian Activity, Morphology, Sediment Pathways, And Provenance, Matthew Chojnacki 2013 University of Tennessee, Knoxville

Martian Dune Fields: Aeolian Activity, Morphology, Sediment Pathways, And Provenance, Matthew Chojnacki

Doctoral Dissertations

Wind has likely been the dominant geologic agent for most of Mars’ history. The wide-spread nature of sand dunes there shows that near-surface winds have commonly interacted with plentiful mobile sediments. Early studies of these dunes suggested minimal activity, dominantly unidirectional simple dune morphologies, and little variations in basaltic sand compositions. This dissertation examines martian sand dunes and aeolian systems, in terms of their activity, morphologies, thermophysical properties, sand compositions, geologic contexts, and source-lithologies using new higher-resolution orbital data. Although previous evidence for contemporary dune activity has been limited, results presented in Chapter II show substantial activity in Endeavour Crater ...


Modeling The Spectral Energy Distribution Of Mrk 421, Randall L. Oglesby 2013 California Polytechnic State University - San Luis Obispo

Modeling The Spectral Energy Distribution Of Mrk 421, Randall L. Oglesby

Physics

Blazars are astronomical objects thought to be powered by the release of gravitational energy by accretion of material into a supermassive black hole located in the central region of the host galaxy. Some AGN present strong relativistic outflows in the form of jets, with blazars being the particular subset whose jets are aligned with our line of sight. Even though blazars account for only a small fraction of all AGN, they are the dominant class source in the high-energy sky. In this thesis we study the spectral energy distribution of Mrk 421, a prototypical blazar. Using publicly available numerical code ...


Active Galactic Nuclei Mergers And Outflows: Observations From Optical And Ultraviolet Emission Lines, Robert Scott Barrows 2013 University of Arkansas, Fayetteville

Active Galactic Nuclei Mergers And Outflows: Observations From Optical And Ultraviolet Emission Lines, Robert Scott Barrows

Theses and Dissertations

I have investigated the nature of a subset of active galactic nuclei (AGN) which show double peaks in their characteristic optical and ultraviolet emission lines. I have performed this investigation through studies of the broad emission line regions (BLRs), which are produced less than 1 pc from the central supermassive black hole (SMBH), and the narrow emission line regions (NLRs), which originate at larger (kpc) distances. The BLR studies consist of detailed line modeling of two individual quasars with double-peaked broad emission line profiles. The modeling suggests there are two primary interpretations of the complex broad line profiles. The first ...


A Variability Study Of The Typical Red Supergiant Antares A, Teznie J D Pugh 2013 The University of Western Ontario

A Variability Study Of The Typical Red Supergiant Antares A, Teznie J D Pugh

Electronic Thesis and Dissertation Repository

Red giants and red supergiants have long been known to be variable. In the last 40 years many of the features of this variability have been associated with large convective cells. Unfortunately, due to the long timescales of these variations they are not well studied, with the exception of the bright M-class supergiant Betelgeuse (α Orionis, M2 Iab). Betelgeuse has been well studied both observationally and theoretically, and has many features that are well described by models of convection. It was these studies of Betelgeuse that provided the main motivation for this thesis. We ask if the dramatic motions seen ...


A Multispectral Assessment Of Complex Impact Craters On The Lunar Farside, Bhairavi Shankar 2013 The University of Western Ontario

A Multispectral Assessment Of Complex Impact Craters On The Lunar Farside, Bhairavi Shankar

Electronic Thesis and Dissertation Repository

Hypervelocity collisions of asteroids onto planetary bodies have catastrophic effects on the target rocks through the process of shock metamorphism. The resulting features, impact craters, are circular depressions with a sharp rim surrounded by an ejecta blanket of variably shocked rocks. With increasing impact energy, the inner crater cavity can preserve complex morphologies including terraced walls, central uplifts, and melted rocks. The lack of erosion due to the absence of water or an atmosphere makes the Moon the perfect target to study impact crater processes, in particular the distribution of highly shocked materials within impact craters of different sizes. This ...


Measurements Of Nh3 Linestrengths And Collisional Broadening Coefficients In N2, O2, Co2, And H2o Near 1103.46 Cm−1, Kyle Owen, Et-touhami Es-sebbar, Aamir Farooq 2013 KAUST

Measurements Of Nh3 Linestrengths And Collisional Broadening Coefficients In N2, O2, Co2, And H2o Near 1103.46 Cm−1, Kyle Owen, Et-Touhami Es-Sebbar, Aamir Farooq

Dr. Et-touhami Es-sebbar

Laser-based ammonia gas sensors have useful applications in many fields including combustion, atmospheric monitoring, and medical diagnostics. Calibration-free trace gas sensors require the spectroscopic parameters including linestrengths and collisional broadening coefficients to be known. Ammonia's strong ν2 vibrational band between View the MathML source has the high absorption strength needed for sensing small concentrations. Within this band, the 1103.46 cm−1 feature is one of the strongest and has minimal interference from CO2 and H2O. However, the six rotational transitions that make up this feature have not been studied previously with absorption spectroscopy due to their small line ...


Effects Of N2o And O2 Addition To Nitrogen Townsend Dielectric Barrier Discharges At Atmospheric Pressure On The Absolute Ground-State Atomic Nitrogen Density, Et. Es-sebbar, N. Gherardi, F. Massines 2013 Paul Scherrer Institute (PSI)

Effects Of N2o And O2 Addition To Nitrogen Townsend Dielectric Barrier Discharges At Atmospheric Pressure On The Absolute Ground-State Atomic Nitrogen Density, Et. Es-Sebbar, N. Gherardi, F. Massines

Dr. Et-touhami Es-sebbar

Absolute ground-state density of nitrogen atoms N (2p3 4S3/2) in non-equilibrium Townsend dielectric barrier discharges (TDBDs) at atmospheric pressure sustained in N2/N2O and N2/O2 gas mixtures has been measured using Two-photon absorption laser-induced fluorescence (TALIF) spectroscopy. The quantitative measurements have been obtained by TALIF calibration using krypton as a reference gas. We previously reported that the maximum of N (2p3 4S3/2) atom density is around 3 × 1014 cm−3 in pure nitrogen TDBD, and that this maximum depends strongly on the mean energy dissipated in the gas. In the two gas mixtures studied here, results show ...


Temperature-Dependent Absorption Cross-Section Measurements Of 1-Butene (1-C4h8) In Vuv And Ir, Et-touhami Es-sebbar, Yves Benilan, Aamir Farooq 2012 Paul Scherrer Institute (PSI)

Temperature-Dependent Absorption Cross-Section Measurements Of 1-Butene (1-C4h8) In Vuv And Ir, Et-Touhami Es-Sebbar, Yves Benilan, Aamir Farooq

Dr. Et-touhami Es-sebbar

Vacuum ultraviolet (VUV) and infrared (IR) absorption cross-section measurements of 1-butene (1-C4H8; CH2=CHCH2CH3; Butylene) are reported over the temperature range of 296–529 K. The VUV measurements are performed between 115 and 205 nm using synchrotron radiation as a tunable VUV light source. Fourier Transform Infrared (FTIR) spectroscopy is employed to measure absorption cross-section and band strengths in the IR region between 1.54 and 25 μm (∼6500–400 cm−1). The measured room-temperature VUV and IR absorption cross-sections are compared with available literature data and are found to be in good agreement. The oscillator strength for the electronic ...


Supernova Resonance-Scattering Line Profiles In The Absence Of A Photosphere, Brian Friesen, E. Baron, David Branch, Bin Chen, Jerod T. Parrent, R. C. Thomas 2012 University of Oklahoma

Supernova Resonance-Scattering Line Profiles In The Absence Of A Photosphere, Brian Friesen, E. Baron, David Branch, Bin Chen, Jerod T. Parrent, R. C. Thomas

Dartmouth Scholarship

In supernova (SN) spectroscopy relatively little attention has been given to the properties of optically thick spectral lines in epochs following the photosphere's recession. Most treatments and analyses of post-photospheric optical spectra of SNe assume that forbidden-line emission comprises most if not all spectral features. However, evidence exists that suggests that some spectra exhibit line profiles formed via optically thick resonance-scattering even months or years after the SN explosion. To explore this possibility, we present a geometrical approach to SN spectrum formation based on the "Elementary Supernova" model, wherein we investigate the characteristics of resonance-scattering in optically thick lines ...


Energetic Galaxy-Wide Outflows In High-Redshift Ultraluminous Infrared Galaxies Hosting Agn Activity, C. M. Harrison, D. M. Alexander, A. M. Swinbank, Ian Smail, S. Alaghband-Zadeh, F. E. Bauer, S. C. Chapman, A. Del Moro, R. C. Hickox 2012 Durham University

Energetic Galaxy-Wide Outflows In High-Redshift Ultraluminous Infrared Galaxies Hosting Agn Activity, C. M. Harrison, D. M. Alexander, A. M. Swinbank, Ian Smail, S. Alaghband-Zadeh, F. E. Bauer, S. C. Chapman, A. Del Moro, R. C. Hickox

Dartmouth Scholarship

We present integral field spectroscopy observations, covering the [O III]4959,5007 emission-line doublet of eight high-redshift (z=1.4-3.4) ultra-luminous infrared galaxies (ULIRGs) that host Active Galactic Nuclei (AGN) activity, including known sub-millimetre luminous galaxies (SMGs). The targets have moderate radio luminosities that are typical of high-redshift ULIRGs (L(1.4GHz)=10^(24)-10^(25)W/Hz) and therefore are not radio-loud AGN. We de-couple kinematic components due to the galaxy dynamics and mergers from those due to outflows. We find evidence in the four most luminous systems (L([O III])>~10^(43)erg/s) for the signatures ...


Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank 2012 Michigan Technological University

Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank

STAR Program Research Presentations

Jupiter’s satellite Europa, whose surface is composed of ice with a possible water ocean beneath, could conceivably serve as an abode for extraterrestrial life. This and other icy celestial bodies may contain organic macromolecular solid material that is produced when surface ices are exposed to ultraviolet radiation and/or electrical energy. Tidal and tectonic stresses or meteorite impacts in icy crusts may produce electrical discharges, which would provide the energy for in-situ synthesis of the organic solids. This electrical energy can be provided by positive hole charge carrier activation. Positive holes exhibit properties such as the ability to flow ...


Stability Of Phyllosilicates On Mars, Patricia Gavin 2012 University of Arkansas, Fayetteville

Stability Of Phyllosilicates On Mars, Patricia Gavin

Theses and Dissertations

This study investigates the stability of phyllosilicates on the surface of Mars through laboratory experiments and analysis of terrestrial analogs. Phyllosilicates are mostly found in the oldest Noachian terrains on Mars and hence hold clues to the planet's earliest aqueous and geologic history. Phyllosilicates relevant to Mars were heated up to ~1100°C for up to 24 hours and impacted with projectile velocities up to ~4.5 km/s. Heated samples were analyzed using x-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy in the near- (NIR, 1.0-2.5 µm) and mid-infrared (MIR, 5.0-15.0 µm) ranges ...


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