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Stellar Nucleosynthesis: Direct Measurement Of The Neutron-Capture Cross Sections Of Stable Germanium Isotopes And Design Of A Next Generation Ion Trap For The Study Of Beta-Delayed Neutron Emission, Alexander Laminack 2020 Louisiana State University and Agricultural and Mechanical College

Stellar Nucleosynthesis: Direct Measurement Of The Neutron-Capture Cross Sections Of Stable Germanium Isotopes And Design Of A Next Generation Ion Trap For The Study Of Beta-Delayed Neutron Emission, Alexander Laminack

LSU Doctoral Dissertations

Knowledge of stellar nuclear reaction rates is critical to understanding the cosmic origins of the abundances of elements. In order to determine these reaction rates, accurate measurements of nuclear cross sections are needed. This thesis presents the results of an experiment to directly measure the neutron capture cross sections of 70-Ge, 72-Ge, 74-Ge, and 76-Ge. These measurements were performed at the Los Alamos Neutron Science CEnter (LANSCE) using the Detector for Advanced Neutron Capture Experiments (DANCE). This is the first direct measurement for many of these isotopes across the neutron energy spectrum of 10 eV to 1 MeV using the ...


Relation Between Gravitational Mass And Baryonic Mass For Non-Rotating And Rapidly Rotating Neutron Stars, He Gao, Shun-Ke Ai, Zhou-Jian Cao, Bing Zhang, Zhen-Yu Zhu, Ang Li, Nai-Bo Zhang, Andreas Bauswein 2020 Beijing Normal University

Relation Between Gravitational Mass And Baryonic Mass For Non-Rotating And Rapidly Rotating Neutron Stars, He Gao, Shun-Ke Ai, Zhou-Jian Cao, Bing Zhang, Zhen-Yu Zhu, Ang Li, Nai-Bo Zhang, Andreas Bauswein

Physics & Astronomy Faculty Publications

With a selected sample of neutron star (NS) equations of state (EOSs) that are consistent with the current observations and have a range of maximum masses, we investigate the relations between NS gravitational mass Mg and baryonic mass Mb, and the relations between the maximum NS mass supported through uniform rotation (Mmax) and that of nonrotating NSs (MTOV). We find that for an EOS-independent quadratic, universal transformation formula (Mb=Mg+A×M2g)(Mb=Mg+A×Mg2), the best-fit A value is 0.080 for non-rotating NSs, 0.064 for maximally rotating NSs, and 0.073 when NSs with arbitrary rotation ...


Full Orbital Solution For The Binary System In The Northern Galactic Disc Microlensing Event Gaia16aye, Ł. Wyrzykowski, P. Mróz, K. A. Rybicki, M. Gromadzki, Z. Kołaczkowski, M. Zieliński, P. Zieliński, N. Britavskiy, A. Gomboc, K. Sokolovsky, S. T. Hodgkin, L. Abe, G. F. Aldi, A. AlMannaei, G. Altavilla, A. Al Qasim, G. C. Anupama, S. Awiphan, E. Bachelet, V. Bakış, S. Baker, S. Bartlett, P. Bendjoya, K. Benson, I. F. Bikmaev, G. Birenbaum, N. Blagorodnova, S. Blanco-Cuaresma, S. Boeva, A. Z. Bonanos, V. Bozza, D. M. Bramich, I. Bruni, R. A. Burenin, U. Burgaz, T. Butterley, H. E. Caines, D. B. Caton, S. Calchi Novati, J. M. Carrasco, A. Cassan, V. Čepas, M. Cropper, M. Chruślińska, G. Clementini, A. Clerici, D. Conti, M. Conti, S. Cross, F. Cusano, G. Damljanovic, D. Dapergolas, G. D'Ago, J. H. J. de Bruijne, M. Dennefeld, V. S. Dhillon, M. Dominik, J. Dziedzic, O. Erece, M. V. Eselevich, H. Esenoglu, L. Eyer, R. Figuera Jaimes, S. J. Fossey, A. I. Galeev, S. A. Grebenev, A. C. Gupta, A. G. Gutaev, N. Hallakoun, A. Hamanowicz, C. Han, B. Hanzlik, J. B. Haislip, L. Hanlon, L. K. Hardy, D. L. Harrison, H. J. van Heerden, V. L. Hoette, K. Horne, R. Hudec, M. Hundertmark, N. Ihanec, E. N. Irtuganov, R. Itoh, P. Iwanek, M. D. Jovanovic, R. Janulis, M. Jelínek, E. L.N. Jensen, Z. Kaczmarek, D. Katz, I. M. Khamitov, Y. Kilic, J. Klencki, U. Kolb, G. Kopacki, V. V. Kouprianov, K. Kruszyńska, S. Kurowski, G. Latev, C.-H. Lee, S. Leonini, G. Leto, F. Lewis, Z. Li, A. Liakos, S. P. Littlefair, J. Lu, C. J. Manser, S. Mao, D. Maoz, A. Martin-Carrillo, J. P. Marais, M. Maskoliūnas, J. R. Maund, P. J. Meintjes, S. S. Melnikov, K. Ment, P. Mikołajczyk, M. Morrell, N. Mowlavi, D. Moździerski, D. Murphy, S. Nazarov, H. Netzel, R. Nesci, C.-C. Ngeow, A. J. Norton, E. O. Ofek, E. Pakštienė, L. Palaversa, A. Pandey, E. Paraskeva, M. Pawlek, M. T. Penny, B. E. Penprase, A. Piascik, J. L. Prieto, J. K. T. Qvam, C. Ranc, A. Rebassa-Mansergas, D. E. Reichert, P. Reig, L. Rhodes, J.-P. Rivet, G. Rixon, D. Roberts, P. Rosi, D. M. Russell, R. Zanmar Sanchez, G. Scarpetta, G. Seabroke, B. J. Shappee, R. Schmidt, Y. Shvartzvald, M. Sitek, J. Skowron, M. Śniegowska, C. Snodgrass, P. S. Soares, B. van Soelen, Z. T. Spetsieri, A. Stankevičiūtė, I. A. Steele, R. A. Street, J. Strobl, E. Strubble, H. Szegedi, L. M. Tinjava Ramirez, L. Tomasella, Y. Tsapras, D. Vernet, S. Villanueva Jr., O. Vince, J. Wambsganss, I. P. van der Westhuizen, K. Wiersema, D. Wium, R. W. Wilson, A. Yoldas, R. Ya. Zhuchkov, D. G. Zhukov, J. Zdanavičius, S. Zoła, A. Zubareva 2020 Swarthmore College

Full Orbital Solution For The Binary System In The Northern Galactic Disc Microlensing Event Gaia16aye, Ł. Wyrzykowski, P. Mróz, K. A. Rybicki, M. Gromadzki, Z. Kołaczkowski, M. Zieliński, P. Zieliński, N. Britavskiy, A. Gomboc, K. Sokolovsky, S. T. Hodgkin, L. Abe, G. F. Aldi, A. Almannaei, G. Altavilla, A. Al Qasim, G. C. Anupama, S. Awiphan, E. Bachelet, V. Bakış, S. Baker, S. Bartlett, P. Bendjoya, K. Benson, I. F. Bikmaev, G. Birenbaum, N. Blagorodnova, S. Blanco-Cuaresma, S. Boeva, A. Z. Bonanos, V. Bozza, D. M. Bramich, I. Bruni, R. A. Burenin, U. Burgaz, T. Butterley, H. E. Caines, D. B. Caton, S. Calchi Novati, J. M. Carrasco, A. Cassan, V. Čepas, M. Cropper, M. Chruślińska, G. Clementini, A. Clerici, D. Conti, M. Conti, S. Cross, F. Cusano, G. Damljanovic, D. Dapergolas, G. D'Ago, J. H. J. De Bruijne, M. Dennefeld, V. S. Dhillon, M. Dominik, J. Dziedzic, O. Erece, M. V. Eselevich, H. Esenoglu, L. Eyer, R. Figuera Jaimes, S. J. Fossey, A. I. Galeev, S. A. Grebenev, A. C. Gupta, A. G. Gutaev, N. Hallakoun, A. Hamanowicz, C. Han, B. Hanzlik, J. B. Haislip, L. Hanlon, L. K. Hardy, D. L. Harrison, H. J. Van Heerden, V. L. Hoette, K. Horne, R. Hudec, M. Hundertmark, N. Ihanec, E. N. Irtuganov, R. Itoh, P. Iwanek, M. D. Jovanovic, R. Janulis, M. Jelínek, E. L.N. Jensen, Z. Kaczmarek, D. Katz, I. M. Khamitov, Y. Kilic, J. Klencki, U. Kolb, G. Kopacki, V. V. Kouprianov, K. Kruszyńska, S. Kurowski, G. Latev, C.-H. Lee, S. Leonini, G. Leto, F. Lewis, Z. Li, A. Liakos, S. P. Littlefair, J. Lu, C. J. Manser, S. Mao, D. Maoz, A. Martin-Carrillo, J. P. Marais, M. Maskoliūnas, J. R. Maund, P. J. Meintjes, S. S. Melnikov, K. Ment, P. Mikołajczyk, M. Morrell, N. Mowlavi, D. Moździerski, D. Murphy, S. Nazarov, H. Netzel, R. Nesci, C.-C. Ngeow, A. J. Norton, E. O. Ofek, E. Pakštienė, L. Palaversa, A. Pandey, E. Paraskeva, M. Pawlek, M. T. Penny, B. E. Penprase, A. Piascik, J. L. Prieto, J. K. T. Qvam, C. Ranc, A. Rebassa-Mansergas, D. E. Reichert, P. Reig, L. Rhodes, J.-P. Rivet, G. Rixon, D. Roberts, P. Rosi, D. M. Russell, R. Zanmar Sanchez, G. Scarpetta, G. Seabroke, B. J. Shappee, R. Schmidt, Y. Shvartzvald, M. Sitek, J. Skowron, M. Śniegowska, C. Snodgrass, P. S. Soares, B. Van Soelen, Z. T. Spetsieri, A. Stankevičiūtė, I. A. Steele, R. A. Street, J. Strobl, E. Strubble, H. Szegedi, L. M. Tinjava Ramirez, L. Tomasella, Y. Tsapras, D. Vernet, S. Villanueva Jr., O. Vince, J. Wambsganss, I. P. Van Der Westhuizen, K. Wiersema, D. Wium, R. W. Wilson, A. Yoldas, R. Ya. Zhuchkov, D. G. Zhukov, J. Zdanavičius, S. Zoła, A. Zubareva

Physics & Astronomy Faculty Works

Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I = 12 mag, and it was covered in great detail with almost 25 000 data points gathered by a network of telescopes. We present the photometric and spectroscopic follow-up covering 500 days of the event evolution. We employed a full Keplerian binary orbit microlensing model combined with the motion of Earth and Gaia around the Sun to ...


Extreme Ultraviolet Quasar Colours From Galex Observations Of The Sdss Dr14q Catalogue, Daniel E. Vanden Berk, Sarah C. Wesolowski, Mary J. Yeckley, Joseph M. Marcinik, Jean M. Quashnock, Lawrence M. Machia, Jian Wu 2020 Old Dominion University

Extreme Ultraviolet Quasar Colours From Galex Observations Of The Sdss Dr14q Catalogue, Daniel E. Vanden Berk, Sarah C. Wesolowski, Mary J. Yeckley, Joseph M. Marcinik, Jean M. Quashnock, Lawrence M. Machia, Jian Wu

Computer Science Faculty Publications

The rest-frame far to extreme ultraviolet (UV) colour–redshift relationship has been constructed from data on over 480,000 quasars carefully cross-matched between SDSS Data Release 14 and the final GALEX photometric catalogue. UV matching and detection probabilities are given for all the quasars, including dependencies on separation, optical brightness, and redshift. Detection limits are also provided for all objects. The UV colour distributions are skewed redward at virtually all redshifts, especially when detection limits are accounted for. The median GALEX far-UV minus near-UV (FUV − NUV) colour–redshift relation is reliably determined up to z ≈ 2.8, corresponding to rest-frame ...


Pb-Pb Dating Of Terrestrial And Extraterrestrial Samples Using Resonance Ionization Mass Spectrometry, F. Scott Anderson, Carolyn Crowe, Jonathan Levine, Tom J. Whitaker 2020 Colgate University Libraries

Pb-Pb Dating Of Terrestrial And Extraterrestrial Samples Using Resonance Ionization Mass Spectrometry, F. Scott Anderson, Carolyn Crowe, Jonathan Levine, Tom J. Whitaker

Physics and Astronomy Faculty Scholarship

We are developing an in-situ, rock-dating spectrometer for spaceflight called the Chemistry, Organics, and Dating EXperiment (CODEX). CODEX will measure Rb-Sr ages on the Moon or Mars, and can be augmented to obtain Pb-Pb ages. Coupling Rb-Sr and Pb-Pb measurements broadens the suite of samples that can be dated, and could provide tests of concordance. Here we assess whether geochronologically meaningful Pb-Pb data could be measured in situ by tuning the prototype CODEX to acquire Pb-Pb data from a suite of well-characterized specimens from the Earth, Moon, and Mars. For Keuhl Lake zircon 91500 our 207Pb/206Pb age of 1090 ...


Long-Range Electroweak Amplitudes Of Single Hadrons From Euclidean Finite-Volume Correlation Functions, Raúl A. Briceño, Zohreh Davoudi, Maxwell T. Hansen, Matthias R. Schindler, Alessandro Baroni 2020 Old Dominion University

Long-Range Electroweak Amplitudes Of Single Hadrons From Euclidean Finite-Volume Correlation Functions, Raúl A. Briceño, Zohreh Davoudi, Maxwell T. Hansen, Matthias R. Schindler, Alessandro Baroni

Physics Faculty Publications

A relation is presented between single-hadron long-range matrix elements defined in a finite Euclidean spacetime and the corresponding infinite-volume Minkowski amplitudes. This relation is valid in the kinematic region where any number of two-hadron states can simultaneously go on shell, so that the effects of strongly coupled intermediate channels are included. These channels can consist of nonidentical particles with arbitrary intrinsic spins. The result accommodates general Lorentz structures as well as nonzero momentum transfer for the two external currents inserted between the single-hadron states. The formalism, therefore, generalizes the work by Christ et al. [Phys. Rev. D 91, 114510 (2015 ...


A Guide To Ligo–Virgo Detector Noise And Extraction Of Transient Gravitational-Wave Signals, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, M. Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny 2020 The University of Texas Rio Grande Valley

A Guide To Ligo–Virgo Detector Noise And Extraction Of Transient Gravitational-Wave Signals, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, M. Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny

Physics and Astronomy Faculty Publications and Presentations

The LIGO Scientific Collaboration and the Virgo Collaboration have cataloged eleven confidently detected gravitational-wave events during the first two observing runs of the advanced detector era. All eleven events were consistent with being from well-modeled mergers between compact stellar-mass objects: black holes or neutron stars. The data around the time of each of these events have been made publicly available through the gravitational-wave open science center. The entirety of the gravitational-wave strain data from the first and second observing runs have also now been made publicly available. There is considerable interest among the broad scientific community in understanding the data ...


Astro2020 Apc White Paper. 2020 Vision: Towards A Sustainable Oir System, Sally Oey, Terry D. Oswalt, Tom Maccarone, Fred Walter, Charles Bailyn, Jay Gallagher, Todd Henry, Derek Buzasi, J. Allyn Smith, Rachael Beaton, Jim Webb, Brad Barlow, Misty Bentz, Leslie Hebb, Patrick Kelly, Jedidah Isler, Michael Meyer, John Salzer, Simone Scaringi 2020 University of Michigan

Astro2020 Apc White Paper. 2020 Vision: Towards A Sustainable Oir System, Sally Oey, Terry D. Oswalt, Tom Maccarone, Fred Walter, Charles Bailyn, Jay Gallagher, Todd Henry, Derek Buzasi, J. Allyn Smith, Rachael Beaton, Jim Webb, Brad Barlow, Misty Bentz, Leslie Hebb, Patrick Kelly, Jedidah Isler, Michael Meyer, John Salzer, Simone Scaringi

Publications

Open-access telescopes of all apertures are needed to operate a competitive and efficient national science program. While larger facilities contribute light-gathering power and angular resolution, smaller ones dominate for field of view, time-resolution, and especially, total available observing time, thereby enabling our entire, diversely-expert community. Smaller aperture telescopes therefore play a critical and indispensable role in advancing science. Thus, the divestment of NSF support for modest-aperture (1 – 4 m) public telescopes poses a serious threat to U.S. scientific leadership, which is compounded by the unknown consequences of the shift from observations driven by individual investigators to survey-driven science. Given ...


Model Comparison From Ligo–Virgo Data On Gw170817’S Binary Components And Consequences For The Merger Remnant, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, M. Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny 2020 The University of Texas Rio Grande Valley

Model Comparison From Ligo–Virgo Data On Gw170817’S Binary Components And Consequences For The Merger Remnant, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, M. Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny

Physics and Astronomy Faculty Publications and Presentations

GW170817 is the very first observation of gravitational waves originating from the coalescence of two compact objects in the mass range of neutron stars, accompanied by electromagnetic counterparts, and offers an opportunity to directly probe the internal structure of neutron stars. We perform Bayesian model selection on a wide range of theoretical predictions for the neutron star equation of state. For the binary neutron star hypothesis, we find that we cannot rule out the majority of theoretical models considered. In addition, the gravitational-wave data alone does not rule out the possibility that one or both objects were low-mass black holes ...


Monitoring Of The Radio Galaxy M 87 During A Low-Emission State From 2012 To 2015 With Magic, Juan P. Madrid 2020 The University of Texas Rio Grande Valley

Monitoring Of The Radio Galaxy M 87 During A Low-Emission State From 2012 To 2015 With Magic, Juan P. Madrid

Physics and Astronomy Faculty Publications and Presentations

M87 is one of the closest (z = 0.004 36) extragalactic sources emitting at very high energies (VHE, E > 100 GeV). The aim of this work is to locate the region of the VHE gamma-ray emission and to describe the observed broad-band spectral energy distribution (SED) during the low VHE gamma-ray state. The data fromM87 collected between 2012 and 2015 as part of aMAGIC monitoring programme are analysed and combined with multiwavelength data from Fermi-LAT, Chandra, HST, EVN, VLBA, and the Liverpool Telescope. The averaged VHE gamma-ray spectrum can be fitted from ∼100 GeV to ∼10 TeV with a simple ...


Toros Optical Follow-Up Of The Advanced Ligo–Virgo O2 Second Observational Campaign, Rodolfo Artola, Martin Beroiz, Juan Cabral, R. Camuccio, Moises Castillo, Mario C. Diaz, Aldo Fonrouge, Alejandro F. Hinojosa, Andrea Hinojosa, Americo F. Hinojosa, Wendy Mendoza, Victor Perez, Tania Penuela, Wahltyn Rattray, Ervin Vilchis, Adam Zadrozny 2020 The University of Texas Rio Grande Valley

Toros Optical Follow-Up Of The Advanced Ligo–Virgo O2 Second Observational Campaign, Rodolfo Artola, Martin Beroiz, Juan Cabral, R. Camuccio, Moises Castillo, Mario C. Diaz, Aldo Fonrouge, Alejandro F. Hinojosa, Andrea Hinojosa, Americo F. Hinojosa, Wendy Mendoza, Victor Perez, Tania Penuela, Wahltyn Rattray, Ervin Vilchis, Adam Zadrozny

Physics and Astronomy Faculty Publications and Presentations

We present themethods and results of the optical follow-up, conducted by the Transient Optical Robotic Observatory of the South Collaboration, of gravitational wave events detected during the Advanced LIGO–Virgo second observing run (2016 November–2017 August). Given the limited field of view (∼100 arcmin) of our observational instrumentation, we targeted galaxies within the area of high localization probability that were observable from our sites. We analysed the observations using difference imaging, followed by a random forest algorithm to discriminate between real and spurious transients. Our observations were conducted using telescopes at Estacion Astrofısica de Bosque Alegre, Cerro Tololo Inter-American ...


Cosmic-Ray Acceleration In The Cygnus Ob2 Stellar Association, Binita Hona 2020 Michigan Technological University

Cosmic-Ray Acceleration In The Cygnus Ob2 Stellar Association, Binita Hona

Dissertations, Master's Theses and Master's Reports

The Cygnus region of our Galaxy consists of an active star forming region and a wealth of various astrophysical sources such as pulsar wind nebulae (PWN), supernova remnants (SNRs), and massive star clusters. Massive stellar clusters and associations have been postulated as possible sources of cosmic rays (CRs) in our Galaxy. One example of a gamma-ray source associated with a stellar association lies in the Cygnus region known as the "Cygnus Cocoon". It is an extended region of gamma-ray emission in the Cygnus X region and attributed to a possible superbubble with freshly accelerated CRs which are hypothesized to produce ...


Exoplanets: Correlated Noise And Cautionary Tales, Ryan Challener 2020 University of Central Florida

Exoplanets: Correlated Noise And Cautionary Tales, Ryan Challener

Electronic Theses and Dissertations, 2020-

Transiting exoplanets provide the best opportunity for planetary characterization, and thus the search for life outside the Solar System. These planets orbit such that they pass in front ("transit'') and behind ("eclipse'') their host star, and a spectrum of the lost flux constrains the atmospheric properties of the planet. In transits, the flux modulation scales with the cross-sectional area of the planet, and the spectrum includes signatures of molecules in the upper atmosphere of the planet's terminator, which the host star's light passes through on the way to the observer. With eclipses, the lost flux is the direct ...


Experimental And Numerical Investigations Of Granular Dynamics In Microgravity, Stephanie Jarmak 2020 University of Central Florida

Experimental And Numerical Investigations Of Granular Dynamics In Microgravity, Stephanie Jarmak

Electronic Theses and Dissertations, 2020-

During the first stages of planet formation small particles (~0.1 – 1 µm) in the protoplanetary disk collide at low relative velocities (less than 1 m/s) and tend to aggregate into cm-size "pebbles" through a combination of electrostatic interactions and gravitational streaming instabilities. Particles in this size regime also compose a layer of regolith on small, airless bodies that evolves under conditions very different than those on Earth. Characterizing the response of regolith to low-energy impacts in a microgravity environment is therefore critical to our understanding of the processes that lead to the formation of these objects and our ...


Investigation Of Small-Scale Energy Release And Transfer Processes In The Solar Atmosphere With High-Resolution Observations In Infrared, Xu Yang 2019 New Jersey Institute of Technology

Investigation Of Small-Scale Energy Release And Transfer Processes In The Solar Atmosphere With High-Resolution Observations In Infrared, Xu Yang

Dissertations

Solar spectrum in the infrared (IR) contains abundant information of solar activities, however, it has not spectral lines in the solar IR spectrum provide different tools to probe the solar atmosphere in various heights. This radiation band in such relatively long wavelength includes various atom and molecule spectral lines that are generated by relatively small energy level transitions. The temperature-sensitive and highly dynamic spectral lines could reveal the energy transmission process more easily than those in the visible wavelength of solar emission. Moreover, the better magnetic sensitivities for the infrared lines resulting from their longer wavelength make them detect the ...


Direct Observation Of Atomic Exchange During Surface Self-Diffusion, Matthew Aaron Koppa 2019 University of New Mexico

Direct Observation Of Atomic Exchange During Surface Self-Diffusion, Matthew Aaron Koppa

Physics & Astronomy ETDs

The diffusion of adatoms across the (100) plane of iridium has been previously inferred to occur by an exchange mechanism based on site mapping. This study provides the first direct observation that surface self-diffusion can occur by exchange. Iridium enriched to ≥93% 191Ir was deposited onto an atomically clean and smooth Ir(100) plane as observed in an atom probe field ion microscope. Following thermally activated surface self-diffusion the adatom was field desorbed and mass analyzed. Observation of the 193Ir isotope in one-half of the cases demonstrates conclusively that atomic exchange can occur during surface self-diffusion.


Stellar Chromospheric Activity And Age Relation From Open Clusters In The Lamost Survey, Jiajun Zhang, Terry Oswalt, Jingkun Zhao, Xiangsong Fang, Gang Zhao, Xilong Liang, Xianhao Ye, Jing Zhong 2019 University of Chinese Academy of Sciences,

Stellar Chromospheric Activity And Age Relation From Open Clusters In The Lamost Survey, Jiajun Zhang, Terry Oswalt, Jingkun Zhao, Xiangsong Fang, Gang Zhao, Xilong Liang, Xianhao Ye, Jing Zhong

Publications

No abstract provided.


Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde 2019 The University of Western Ontario

Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde

Electronic Thesis and Dissertation Repository

Volcanism has played a significant role throughout Mars’ geologic history. Extensive lava flows are widely spread across Mars’ equatorial region, shaping the surface in a very distinct way. In radar images (at the decimeter scale), these flows are bright, which is a typical characteristic of extremely rough, blocky lavas flows seen on Earth. Although the source of the extreme roughness of Martian lava flows is unknown, their surface roughness parameters can be constrained to 1) gain information about Mars’ interior processes, 2) find appropriate analogues on other planetary bodies, and 3) ideally infer the emplacement style of such lavas. Here ...


New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd 2019 University of New Mexico

New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Mathematics and Statistics Faculty and Staff Publications

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was "to get rid of the infinities in the calculations. The infinities are still there, but now they can ...


An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port 2019 University of Arkansas, Fayetteville

An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port

Theses and Dissertations

Since its detection in the 1960s the source of the unusual radar emissivity signal seen on several highlands on Venus has long eluded researchers. Researchers have determined that a mineral with a high dielectric constant could explain the signal. Using a Venus simulation chamber, we experimentally investigated this enigma to build upon the candidate mineral list that has been compiled over the last several decades. We tested the stability of 8 different minerals and elements at two to three different temperature/pressure regimes in three different gas mixtures meant to simulate the conditions found on Venus for a period of ...


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