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Methanol Masers In Star-Forming Regions, Nicolas Clarisse, Anuj P. Sarma 2019 DePaul University

Methanol Masers In Star-Forming Regions, Nicolas Clarisse, Anuj P. Sarma

DePaul Discoveries

Methanol molecules in star-forming regions emit detectable microwave radiation. In particular, the rotational energy state transitions of methanol are responsible for two types of masers: Class I and Class II, found in the bipolar outflows and accretion disks of star-forming regions, respectively. Masers, being intense point-like sources in our sky, serve as an excellent source of information in further understanding the environment of high-mass star-forming regions due to their intense luminosities. High-mass star formation is still not entirely understood and remains an observational challenge. We have compiled a list of all the methanol maser transitions observed in the literature, in ...


Hierarchical Structure Formation In The Sdss Eboss Ly-Alpha Forests, Devin Becker 2019 DePaul University

Hierarchical Structure Formation In The Sdss Eboss Ly-Alpha Forests, Devin Becker

DePaul Discoveries

In this study, we examine hierarchical structure at large redshifts utilizing Sloan Digital Sky Survey (SDSS) Lyman-alpha forest data. Lyman-alpha forests are absorption lines in the spectrum of quasars that serve as tracers for clouds of primordial hydrogen. These data serve as a 1-dimensional probe of the matter density field at high redshift. Using a measure sensitive to hierarchical structure formation assembled around a discrete wavelet transform, we were able to detect hierarchical structure formation in the spectrum of every quasar studied. The nature of the hierarchy seems to pertain to two forms: one that is constant across all scales ...


Phase Retrieval Using A Genetic Algorithm On The Systematic Image-Based Optical Alignment Test Bed, Jaime R. Taylor 2019 Marshall University

Phase Retrieval Using A Genetic Algorithm On The Systematic Image-Based Optical Alignment Test Bed, Jaime R. Taylor

Dr. Jaime R. Taylor

NASA’s Marshall Space Flight Center’s Systematic Image-Based Optical Alignment (SIBOA) Testbed was developed to test phase retrieval algorithms and hardware techniques. Individuals working with the facility developed the idea of implementing phase retrieval by breaking the determination of the tip/tilt of each mirror apart from the piston motion (or translation) of each mirror. Presented in this report is an algorithm that determines the optimal phase correction associated only with the piston motion of the mirrors.


New Tests Of General Relativity, Quentin Bailey 2019 Embry-Riddle Aeronautical University

New Tests Of General Relativity, Quentin Bailey

Quentin Bailey

The last decade has seen a rapid increase in the number of precision tests of relativity. This research has been motivated by the intriguing possibility that tiny deviations from relativity might arise in the underlying theory that is widely believed to successfully mesh General Relativity (GR) with quantum physics. Many of these tests have been analyzed within an effective field theory framework which generically describes possible deviations from exact relativity and contains some traditional test frameworks as limiting cases. One part of the activity has been a resurgence of interest in tests of relativity in the Minkowski-spacetime context, where Lorentz ...


What Do We Know About Lorentz Symmetry?, Q. G. Bailey 2019 Embry-Riddle Aeronautical University

What Do We Know About Lorentz Symmetry?, Q. G. Bailey

Quentin Bailey

Precision tests of Lorentz symmetry have become increasingly of interest to the broader gravitational and high-energy physics communities. In this talk, recent work on violations of local Lorentz invariance in gravity is discussed, including recent analysis constraining Lorentz violation in a variety of gravitational tests. The arena of short-range tests of gravity is highlighted, demonstrating that such tests are sensitive to a broad class of unexplored signals that depend on sidereal time and the geometry of the experiment.


Tests Of Lorentz Symmetry In The Gravitational Sector, Aurélien Hees, Quentin G. Bailey, Adrien Bourgoin, Hélène Pihan-Le Bars, Christine Guerlin, Christophe Le Poncin-Lafitte 2019 University of California, Los Angeles

Tests Of Lorentz Symmetry In The Gravitational Sector, Aurélien Hees, Quentin G. Bailey, Adrien Bourgoin, Hélène Pihan-Le Bars, Christine Guerlin, Christophe Le Poncin-Lafitte

Quentin Bailey

Lorentz symmetry is one of the pillars of both General Relativity and the Standard Model of particle physics. Motivated by ideas about quantum gravity, unification theories and violations of CPT symmetry, a significant effort has been put the last decades into testing Lorentz symmetry. This review focuses on Lorentz symmetry tests performed in the gravitational sector. We briefly review the basics of the pure gravitational sector of the Standard-Model Extension (SME) framework, a formalism developed in order to systematically parametrize hypothetical violations of the Lorentz invariance. Furthermore, we discuss the latest constraints obtained within this formalism including analyses of the ...


Prospects For Sme Tests With Experiments At Syrte And Lkb, C. Guerlin, H. Pihan-Le Bars, Q. G. Bailey, P. Wolf 2019 ENS-PSL Research University

Prospects For Sme Tests With Experiments At Syrte And Lkb, C. Guerlin, H. Pihan-Le Bars, Q. G. Bailey, P. Wolf

Quentin Bailey

Preliminary work has been done in order to assess the perspectives of metrology and fundamental physics atomic experiments at SYRTE and LKB in the search for physics beyond the Standard Model and General Relativity. The first studies we identified are currently ongoing with the Microscope mission and with a Cs fountain clock. The latter brings significant improvement on the proton-sector coefficient cTT down to the 10−17 GeV level.


Improved Tests Of Lorentz Invariance In The Matter Sector Using Atomic Clocks, H. Pihan-Le Bars, C. Guerlin, Q. G. Bailey, S. Bize, P. Wolf 2019 SYRTE

Improved Tests Of Lorentz Invariance In The Matter Sector Using Atomic Clocks, H. Pihan-Le Bars, C. Guerlin, Q. G. Bailey, S. Bize, P. Wolf

Quentin Bailey

For the purpose of searching for Lorentz-invariance violation in the minimal Standard-Model Extension, we perfom a reanalysis of data obtained from the 133Cs fountain clock operating at SYRTE. The previous study led to new limits on eight components of the ˜cµν tensor, which quantifies the anisotropy of the proton’s kinetic energy. We recently derived an advanced model for the frequency shift of hyperfine Zeeman transition due to Lorentz violation and became able to constrain the ninth component, the isotropic coefficient c˜TT, which is the least well-constrained coefficient of ˜cµν. This model is based on a second-order boost Lorentz ...


Lorentz-Violating Electromagnetostatics, Quentin G. Bailey 2019 Indiana University - Bloomington

Lorentz-Violating Electromagnetostatics, Quentin G. Bailey

Quentin Bailey

In this talk, the stationary limit of Lorentz-violating electrodynamics is discussed. As illustrated by some simple examples, the general solution includes unconventional mixing of electrostatic and magnetostatic effects. I discuss a high-sensitivity null-type measurement, exploiting Lorentz-violating electromagnetostatic effects, that could improve existing limits on parity-odd coefficients for Lorentz violation in the photon sector.


Constraints On Sme Coefficients From Lunar Laser Ranging, Very Long Baseline Interferometry, And Asteroid Orbital Dynamics, C. Le Poncin-Lafitte, A. Bourgoin, A. Hees, S. Bouquillon, S. Lambert, Q. G. Bailey, et al. 2019 SYRTE

Constraints On Sme Coefficients From Lunar Laser Ranging, Very Long Baseline Interferometry, And Asteroid Orbital Dynamics, C. Le Poncin-Lafitte, A. Bourgoin, A. Hees, S. Bouquillon, S. Lambert, Q. G. Bailey, Et Al.

Quentin Bailey

Lorentz symmetry violations can be parametrized by an effective field theory framework that contains both General Relativity and the Standard Model of particle physics, called the Standard-Model Extension or SME. We consider in this work only the pure gravitational sector of the minimal SME. We present new constraints on the SME coefficients obtained from lunar laser ranging, very long baseline interferometry, and planetary motions.


Gravity Sector Of The Sme, Q. G. Bailey 2019 Embry-Riddle Aeronautical University

Gravity Sector Of The Sme, Q. G. Bailey

Quentin Bailey

In this talk, the gravity sector of the effective field theory description of local Lorentz violation is discussed, including minimal and nonminimal curvature couplings. Also, recent experimental and observational analyses including solar-system ephemeris and short-range gravity tests are reviewed.


Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 4: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 4: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 1: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 1: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 7: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 7: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


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