Asteroid Belt Survival Through Stellar Evolution: Dependence On The Stellar Mass,
2020
University of Nevada, Las Vegas
Asteroid Belt Survival Through Stellar Evolution: Dependence On The Stellar Mass, Rebecca G. Martin, Mario Livio, Jeremy L. Smallwood, Cheng Chen
Physics & Astronomy Faculty Research
Polluted white dwarfs are generally accreting terrestrial-like material that may originate from a debris belt like the asteroid belt in the Solar system. ... See full text for complete abstract.
The Effects Of Disc Self-Gravity And Radiative Cooling On The Formation Of Gaps And Spirals By Young Planets,
2020
University of Nevada, Las Vegas
The Effects Of Disc Self-Gravity And Radiative Cooling On The Formation Of Gaps And Spirals By Young Planets, Shangjia Zhang, Zhaohuan Zhu
Physics & Astronomy Faculty Research
We have carried out 2D hydrodynamical simulations to study the effects of disc self-gravity and radiative cooling on the formation of gaps and spirals. (1) With disc self-gravity included, we find stronger, more tightly wound spirals and deeper gaps in more massive discs. The deeper gaps are due to the larger Angular Momentum Flux (AMF) of the waves excited in more massive discs, as expected from the linear theory. The position of the secondary gap does not change, provided that the disc is not extremely massive (Q ≳ 2). (2) With radiative cooling included, the excited spirals become monotonically more …
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,
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 …
There Is No Constant In Physics: A Neutrosophic Explanation,
2020
University of New Mexico
There Is No Constant In Physics: A Neutrosophic Explanation, Victor Christianto, Robert Neil Boyd, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
In Neutrosophic Logic, a basic assertion is that there are variations of about everything that we can measure; the variations surround three parameters called T,I,F (truth, indeterminacy, falsehood) which can take a range of values. Similarly, in this paper we consider NL applications in physics constants. Those constants actually all have a window of plus and minus values, relative to the average value of the constant. For example, speed of light, c, can vary in a window up to +/- 3000 m/s. Therefore it should be written: 300000 km/s +/- 3 km/s. We also discuss some implications of this new …
Searching For The Common Suprathermal Power Law Tail In Parker Solar Probe's Isois Data,
2020
University of New Hampshire, Durham
Searching For The Common Suprathermal Power Law Tail In Parker Solar Probe's Isois Data, Asher S. Merrill
Honors Theses and Capstones
Results from the Advanced Composition Explorer (ACE) and the Ulysses spacecraft suggested the existence of a pervasive power-law spectrum of suprathermal ions in the solar wind with a spectral index of -3/2. This distribution is of particular interest to humanity because the suprathermal ions it describes can serve as the seed population for large, destructive events that can harm ground- and air-based equipment. It has been suggested that various statistical mechanisms can produce the observed spectrum, however the underlying physical phenomena are not yet known. The spectrum of suprathermal ions is relatively unstudied closer to the Sun than 1 au. …
A Review On Superluminal Physics And Superluminal Communication In Light Of The Neutrosophic Logic Perspective,
2020
University of New Mexico
A Review On Superluminal Physics And Superluminal Communication In Light Of The Neutrosophic Logic Perspective, Victor Christianto, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
In a recent paper, we describe a model of quantum communication based on combining consciousness experiment and entanglement, which can serve as impetus to stop 5G-network-caused diseases. Therefore, in this paper we consider superluminal physics and superluminal communication as a bridge or intermediate way between subluminal physics and action-at-a-distance (AAAD) physics, especially from neutrosophic logic perspective. Although several ways have been proposed to bring such a superluminal communication into reality, such as Telluric wave or Telepathy analog of Horejev and Baburin, here we also review two possibilities: quaternion communication and also quantum communication based on quantum noise. Further research is …
New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug,
2019
University of New Mexico
New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd
Branch 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 …
Morphological Signatures Induced By Dust Back Reactions In Discs With An Embedded Planet,
2019
University of Nevada, Las Vegas
Morphological Signatures Induced By Dust Back Reactions In Discs With An Embedded Planet, Chao-Chin Yang, Zhaohuan Zhu
Physics & Astronomy Faculty Research
Recent observations have revealed a gallery of substructures in the dust component of nearby protoplanetary discs, including rings, gaps, spiral arms, and lopsided concentrations. One interpretation of these substructures is the existence of embedded planets. Not until recently, however, most of the modelling effort to interpret these observations ignored the dust back reaction to the gas. In this work, we conduct local-shearing-sheet simulations for an isothermal, inviscid, non-self-gravitating, razor-thin dusty disc with a planet on a fixed circular orbit. We systematically examine the parameter space spanned by planet mass (0.1Mth ≤ Mp ≤ 1Mth, where Mth is the thermal mass), …
Nonideal Mhd Simulation Of Hl Tau Disk: Formation Of Rings,
2019
University of Nevada, Las Vegas
Nonideal Mhd Simulation Of Hl Tau Disk: Formation Of Rings, Xiao Hu, Zhaohuan Zhu, Satoshi Okuzumi, Xue-Ning Bai, Lile Wang, Kengo Tomida, James M. Stone
Physics & Astronomy Faculty Research
Recent high-resolution observations unveil ring structures in circumstellar disks. The origin of these rings has been widely investigated under various theoretical scenarios. In this work we perform global 3D nonideal MHD simulations including effects from both ohmic resistivity and ambipolar diffusion (AD) to model the HL Tau disk. The nonideal MHD diffusion profiles are calculated based on the global dust evolution calculation including sintering effects. Disk ionization structure changes dramatically across the snow line due to the change of dust size distribution close to the snow line of major volatiles. We find that accretion is mainly driven by disk wind. …
The Frb 121102 Host Is Atypical Among Nearby Fast Radio Bursts,
2019
Peking University
The Frb 121102 Host Is Atypical Among Nearby Fast Radio Bursts, Ye Li, Bing Zhang, Kentaro Nagamine, Jingjing Shi
Physics & Astronomy Faculty Research
We search for host galaxy candidates of nearby fast radio bursts (FRBs), FRB 180729.J1316+55, FRB 171020, FRB 171213, FRB 180810.J1159+83, and FRB 180814.J0422+73 (the second repeating FRB). We compare the absolute magnitudes and the expected host dispersion measure DMhost of these candidates with that of the first repeating FRB, FRB 121102, as well as those of long gamma-ray bursts (LGRBs) and superluminous supernovae (SLSNe), the proposed progenitor systems of FRB 121102. We find that while the FRB 121102 host is consistent with those of LGRBs and SLSNe, the nearby FRB host candidates, at least for FRB 180729.J1316+55, FRB 171020, and …
A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes,
2019
Centro de Astrobiologia
A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga
Physics & Astronomy Faculty Research
Context. Understanding the physics and geometry of accretion and ejection around super massive black holes (SMBHs) is important to understand the evolution of active galactic nuclei (AGN) and therefore of the large scale structures of the Universe. Aims. We aim at providing a simple, coherent, and global view of the sub-parsec accretion and ejection flow in AGN with varying Eddington ratio, ṁ, and black hole mass, MBH. Methods. We made use of theoretical insights, results of numerical simulations, as well as UV and X-ray observations to review the inner regions of AGN by including different accretion and ejection modes, with …
Preparing A Database Of Extremely High Velocity Outflows In Quasars,
2019
Humboldt State University
Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo
IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt
No abstract provided.
The Frequency Of Kozai–Lidov Disc Oscillation Driven Giant Outbursts In Be/X-Ray Binaries,
2019
University of Nevada, Las Vegas
The Frequency Of Kozai–Lidov Disc Oscillation Driven Giant Outbursts In Be/X-Ray Binaries, Rebecca G. Martin, Alessia Franchini
Physics & Astronomy Faculty Research
Giant outbursts of Be/X-ray binaries may occur when a Be-star disc undergoes strong eccentricity growth due to the Kozai–Lidov (KL) mechanism. The KL effect acts on a disc that is highly inclined to the binary orbital plane provided that the disc aspect ratio is sufficiently small. The eccentric disc overflows its Roche lobe and material flows from the Be star disc over to the companion neutron star causing X-ray activity. With N-body simulations and steady state decretion disc models we explore system parameters for which a disc in the Be/X-ray binary 4U 0115+634 is KL unstable and the resulting time-scale …
The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement,
2019
University of Arkansas, Fayetteville
The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement, Michael S. Fusco
Graduate Theses and Dissertations
This dissertation pertains to the geometric structure of late type (spiral) galaxies, specifically on the relation between the logarithmic spiral pitch angle of the galactic spiral arms with other properties of the galaxy, such as central Supermassive Black Hole (SMBH) mass. Our work continues a study of the Black Hole Mass Function (BHMF) in local galaxies by recording the pitch angles of spiral galaxies with lower surface brightness than were previously included. We also conduct a case study on the structure of an interestingly shaped galaxy, UGC 4599. Previous studies on the topic of spiral arm pitch angles have measured …
One-Note-Samba Approach To Cosmology,
2019
University of New Mexico
One-Note-Samba Approach To Cosmology, Florentin Smarandache, Victor Christianto
Branch Mathematics and Statistics Faculty and Staff Publications
Inspired by One Note Samba, a standard jazz repertoire, we present an outline of Bose-Einstein Condensate Cosmology. Although this approach seems awkward and a bit off the wall at first glance, it is not impossible to connect altogether BEC, Scalar Field Cosmology and Feshbach Resonance with Ermakov-Pinney equation. We also briefly discuss possible link with our previous paper which describes Newtonian Universe with Vortex in terms of Ermakov equation.
Circumbinary Disk Inner Radius As A Diagnostic For Disk–Binary Misalignment,
2019
University of Nevada, Las Vegas
Circumbinary Disk Inner Radius As A Diagnostic For Disk–Binary Misalignment, Alessia Franchini, Stephen H. Lubow, Rebecca G. Martin
Physics & Astronomy Faculty Research
We investigate the misalignment of the circumbinary disk around the binary HD 98800 BaBb with eccentricity e sime 0.8. Kennedy et al. observed the disk to be either at an inclination of 48° or polar aligned to the binary orbital plane. Their simulations showed that alignment from 48° to a polar configuration can take place on a shorter timescale than the age of this system. We perform hydrodynamical numerical simulations in order to estimate the cavity size carved by the eccentric binary for different disk inclinations as an independent check of polar alignment. Resonance theory suggests that torques on the …
Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data,
2019
California Polytechnic State University, San Luis Obispo
Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data, Matthew Aaron Salinas
Physics
Brightest Cluster Galaxies (BCGs), the brightest galaxy in a cluster of hundreds to thousands of galaxies, are some of the biggest, brightest, and most massive galaxies in the universe. Characterizing a BCG can help discover more about galaxy evolution - the aging, changing, and possible merging (collisions) of galaxies. This project involves determining the separation of the peak of x-ray emission of the galaxy cluster, and the peak of visible emission of the BCG to characterize the system as being disturbed or undisturbed that can then lead to discoveries about its formation and evolution. We have found that 17.4% of …
A Tight Relation Between Spiral Arm Pitch Angle And Protplanetary Disk Mass,
2019
Peking University
A Tight Relation Between Spiral Arm Pitch Angle And Protplanetary Disk Mass, Si-Yue Yu, Luis C. Ho, Zhaohuan Zhu
Physics & Astronomy Faculty Research
We use two-dimensional Fourier transformation to measure the pitch angle () of the dominant spiral Fourier mode of well-defined spiral arms in 13 protoplanetary disks, making use of near-infrared scattered-light images of AB Aur, SAO 206462, MWC 758, V1247 Ori, HD 142527, DZ Cha, LkHα 330, and HD 100453, and ALMA millimeter continuum images of Elias 2-27, IM Lup, AS 205, and HT Lup. We find that the measured pitch angle correlates strongly with disk mass (M D ), such that more massive protoplanetary disks have smaller pitch angles, following . Interestingly, four disks with a known companion (HD 142527, …
Induced Magnetic Dipole On Jupiter’S Moon Europa,
2019
Embry-Riddle Aeronautical University
Induced Magnetic Dipole On Jupiter’S Moon Europa, Luke Francis, Michele Zanolin
Student Works
Physics can have some of the most unique and extraordinary applications of basic principles applied on a larger scale. This paper will explore the properties of induced magnetic dipoles and will examine this phenomenon directly from Jupiter's moon, Europa. These properties will be used to determine if there is liquid water beneath its icy surface and how this conclusion was verified. This will be accomplished using the concepts of magnetic dipoles and induced currents. Recent missions have also revealed estimates of the depth of Europa's subsurface ocean. There have been many measurements taken of Europa's magnetic field, and they are …
Alignment Of A Circumbinary Disc Around An Eccentric Binary With Application To Kh 15d,
2019
University of Nevada, Las Vegas
Alignment Of A Circumbinary Disc Around An Eccentric Binary With Application To Kh 15d, Jeremy L. Smallwood, Stephen H. Lubow, Alessia Franchini, Rebecca G. Martin
Physics & Astronomy Faculty Research
We analyse the evolution of a mildly inclined circumbinary disc that orbits an eccentric orbit binary by means of smoothed particle hydrodynamics (SPH) simulations and linear theory. We show that the alignment process of an initially misaligned circumbinary disc around an eccentric orbit binary is significantly different than around a circular orbit binary and involves tilt oscillations. The more eccentric the binary, the larger the tilt oscillations and the longer it takes to damp these oscillations. A circumbinary disc that is only mildly inclined may increase its inclination by a factor of a few before it moves towards alignment. The …
