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Articles 151 - 180 of 533

Full-Text Articles in Astrophysics and Astronomy

Gyrochronology Of Wide Binaries In The Kepler K2 Fields, Alexander Stone-Martinez, Gustavo Villarroel, Patrice Majewski, Tomomi Otani, Terry Oswalt, Andrew Mcnaughton Jan 2017

Gyrochronology Of Wide Binaries In The Kepler K2 Fields, Alexander Stone-Martinez, Gustavo Villarroel, Patrice Majewski, Tomomi Otani, Terry Oswalt, Andrew Mcnaughton

Publications

Gyrochronology is the method of determining a stars age based on its rotation period and mass. A cool main sequence star loses it's angular momentum as it ages, so the rotation rate slows down. Gyrochronology has been tested on star clusters in previous studies and now we are applying the theory to binary stars. Components of a binary should be the same age, so Gyrochronology should return the same age for both stars in binary systems. We examined the rotation periods for 290 wide binary main sequence stars in the Kepler K2 fields. These observations are part of a continuing …

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O-C Analysis Of The Pulsating Subdwarf B Star Pg 1219 + 534, Tomomi Otani, Terry Oswalt, Alexander Stone-Martinez, Dana Singh, Kenneth Sampson, Aliyah Khan, Austin Seepersad, Caila Deabreu, Adam Moss, Claudia Morello Jan 2017

O-C Analysis Of The Pulsating Subdwarf B Star Pg 1219 + 534, Tomomi Otani, Terry Oswalt, Alexander Stone-Martinez, Dana Singh, Kenneth Sampson, Aliyah Khan, Austin Seepersad, Caila Deabreu, Adam Moss, Claudia Morello

Publications

PG 1219 + 534 (KY Uma) is a subdwarf B pulsating star with multiple periodicities between 120 – 175 s. PG 1219 + 534 was monitored for 90 hours during 2010-1 and 2016 using the 0.9 m SARA-KP telescope at Kitt Peak National Observatory (KPNO) in Arizona and the 0.8m Ortega telescope at Florida Institute of Technology in Melbourne, Florida. So far, the most promising theory for the origin of subdwarf B (sdB) stars is that they result from binary mass transfer near the Helium Flash stage of evolution. The observations of PG 1219 + 534 reported here are part …

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Gyrochronology Of Wide Binaries In The Kepler K2 Campaign 5 Field, Terry D. Oswalt, Derek Buzasi, Tomomi Otani Jan 2017

Gyrochronology Of Wide Binaries In The Kepler K2 Campaign 5 Field, Terry D. Oswalt, Derek Buzasi, Tomomi Otani

Publications

We are determining rotation periods for an ensemble of over 100 wide non-interacting binary stars in the K2 Campaign 5 field that contain two main sequence dwarfs, as well as a smaller sample containing at least one white dwarf component. Observations of such coeval pairs provide the basis for our new investigation of rotation-based age determinations. Such “gyrochronology” ages can achieve a precision that exceeds most other current method of stellar age determination. Here we present a status report on our analysis of the light curves extracted from the K2 Campaign 5 field.

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Search For Binaries In The Kepler K2 Fields Using Pulsation Timing Method, Tomomi Otani, Terry Oswalt Jan 2017

Search For Binaries In The Kepler K2 Fields Using Pulsation Timing Method, Tomomi Otani, Terry Oswalt

Publications

Finding orbital solutions of binaries which have small mass ratios (50 days) is challenging using traditional techniques. The radial velocity method is a good way to detect such binary stars, however it requires large telescopes. Therefore, the search for binaries in those regions is still incomplete. For binaries in this regime with at least one component that pulsates, pulsation timing is a better approach. Orbital solutions for such systems can be obtained from the periodic change in pulse arrival times as the star’s reflex motion is manifested by the changing distance along the line of sight. We present a search …

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Testing The Stellar Rotation Vs. Age Paradigm Using Wide Binaries In The Kepler & K2 Fields, T. D. Oswalt, T. Otani, A. Stone-Martinez, P. Majewski, D. Buzasi Jan 2017

Testing The Stellar Rotation Vs. Age Paradigm Using Wide Binaries In The Kepler & K2 Fields, T. D. Oswalt, T. Otani, A. Stone-Martinez, P. Majewski, D. Buzasi

Publications

Essential to understanding the history of the Galaxy’s stellar populations, ages are among the most difficult to measure properties of stars. Accurate stellar ages would provide key leverage on problems ranging from the habitability of exoplanets to the Galaxy’s chemical evolution and age. Gyrochronology, the empirical relation between rotation and age, is believed to be among the best current methods of stellar age determination. Using several hundred wide non-interacting binaries identified in the Kepler mission “K2” extended mission fields we are testing this paradigm. Such wide pairs afford a unique opportunity to unravel and calibrate the effects of mass, rotation, …

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First Performance Results Of A New Field-Widened Spatial Heterodyne Spectrometer For Geocoronal Hα Research, D. D. Gardner, E. J. Mierkiewicz, F. L. Roesler, J. M. Harlander, K. P. Jaehnig, S. M. Nossal, L. M. Haffner Jan 2017

First Performance Results Of A New Field-Widened Spatial Heterodyne Spectrometer For Geocoronal Hα Research, D. D. Gardner, E. J. Mierkiewicz, F. L. Roesler, J. M. Harlander, K. P. Jaehnig, S. M. Nossal, L. M. Haffner

Publications

A new, high-resolution field-widened spatial heterodyne spectrometer (FW-SHS) designed to observe geocoronal Balmer α (Hα, 6563 Å) emission was installed at Pine Bluff Observatory (PBO) near Madison, Wisconsin. FW-SHS observations were compared with an already well-characterized dual-etalon Fabry-Perot Interferometer (PBO FPI) optimized for Hα, also at PBO. The FW-SHS is a robust Fourier transform instrument that combines a large throughput advantage with high spectral resolution and a relatively long spectral baseline (~10 times that of the PBO FPI) in a compact, versatile instrument with no moving parts.Coincident Hα observations by FW-SHS and PBO FPI were obtained over similar integration times, …

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The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Dec 2016

The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

A transient gravitational-wave signal, GW150914, was identified in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To assess the implications of this discovery, the detectors remained in operation with unchanged configurations over a period of 39 days around the time of the signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous two-detector observational data is estimated to have a false-alarm rate (FAR) of

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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 Dec 2016

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

Publications

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 …

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Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Dec 2016

Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in the range 2–600 Gpc−3 yr−1. Here we give details on our method and computations, including information about our search pipelines, a derivation of our likelihood function for the analysis, a description of the astrophysical search trigger distribution expected from merging BBHs, details on our computational methods, a description of the effects and our model for calibration uncertainty, …

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Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, Michele Zanolin, Et Al. Nov 2016

Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, Michele Zanolin, Et Al.

Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the S6 LIGO science run. The search was possible thanks to the computing power provided by the volunteers of the Einstein@Home distributed computing project.

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Improved Analysis Of Gw150914 Using A Fully Spin-Precessing Waveform Model, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Oct 2016

Improved Analysis Of Gw150914 Using A Fully Spin-Precessing Waveform Model, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 [Abbott et al. Phys. Rev. Lett. 116, 061102 (2016).]. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] presented parameter estimation of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and an 11-dimensional nonprecessing effective-one-body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here, we present new results that include a 15-dimensional precessing-spin waveform model (precessing EOBNR) developed within the EOB formalism. (See article for remainder of abstract.)

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Magnetic Reconnection With A Fast Perpendicular Sheared Flow, Xuanye Ma, Antonius Otto, Peter A. Delamere Oct 2016

Magnetic Reconnection With A Fast Perpendicular Sheared Flow, Xuanye Ma, Antonius Otto, Peter A. Delamere

Publications

Magnetic reconnection at the Earth's low‐latitude magnetopause near the flank region is likely associated with a large sheared flow, being frequently quasi‐perpendicular to the antiparallel magnetic field components. The magnitude of a fast sheared flow can be super‐Alfvénic and even overcome the local fast mode speed. A scaling analysis implies a contradiction between the Walén relation and the balance of the total pressure for magnetic reconnection with a supercritical perpendicular sheared flow. This study uses one‐ and two‐dimensional magnetohydrodynamic (MHD) simulations to demonstrate that the traditional reconnection layer violates the Walén relation but still maintains the total pressure balance in …

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Book Review: The International Atlas Of Mars Exploration: From Spirit To Curiosity: V.2: 2004 To 2014, T. D. Oswalt Oct 2016

Book Review: The International Atlas Of Mars Exploration: From Spirit To Curiosity: V.2: 2004 To 2014, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of The International Atlas of Mars Exploration: from Spirit to Curiosity : V.2: 2004 to 2014 by Philip J. Stooke. 444p bibl index, 9781107030930 $145.00, 9781139344470 LC Call Number: 1000

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Anisotropic Cubic Curvature Couplings, Quentin G. Bailey Sep 2016

Anisotropic Cubic Curvature Couplings, Quentin G. Bailey

Publications

To complement recent work on tests of spacetime symmetry in gravity, cubic curvature couplings are studied using an effective field theory description of spacetime-symmetry breaking. The associated mass-dimension-eight coefficients for Lorentz violation studied do not result in any linearized gravity modifications and instead are revealed in the first nonlinear terms in an expansion of spacetime around a flat background. We consider effects on gravitational radiation through the energy loss of a binary system and we study two-body orbital perturbations using the post-Newtonian metric. Some effects depend on the internal structure of the source and test bodies, thereby breaking the weak …

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Directly Comparing Gw150914 With Numerical Solutions Of Einstein's Equations For Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Sep 2016

Directly Comparing Gw150914 With Numerical Solutions Of Einstein's Equations For Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We compare GW150914 directly to simulations of coalescing binary black holes in full general relativity, including several performed specifically to reproduce this event. Our calculations go beyond existing semianalytic models, because for all simulations—including sources with two independent, precessing spins—we perform comparisons which account for all the spin-weighted quadrupolar modes, and separately which account for all the quadrupolar and octopolar modes. Consistent with the posterior distributions reported by Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016)] (at the 90% credible level), we find the data are compatible with a wide range of nonprecessing and precessing simulations. Follow-up simulations performed …

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Bayesian Analysis Of Two Stellar Populations In Galactic Globular Clusters – Iii. Analysis Of 30 Clusters, R. Wagner-Kaiser, D. C. Stenning, A Sarajedini, Ted Von Hippel, D. A. Van Dyk, E. Robinson, W. H. Jefferys Sep 2016

Bayesian Analysis Of Two Stellar Populations In Galactic Globular Clusters – Iii. Analysis Of 30 Clusters, R. Wagner-Kaiser, D. C. Stenning, A Sarajedini, Ted Von Hippel, D. A. Van Dyk, E. Robinson, W. H. Jefferys

Publications

We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACS Treasury observations of 30 Galactic globular clusters to characterize two distinct stellar populations. A sophisticated Bayesian technique is employed to simultaneously sample the joint posterior distribution of age, distance, and extinction for each cluster, as well as unique helium values for two populations within each cluster and the relative proportion of those populations. We find the helium differences among the two populations in the clusters fall in the range of ∼0.04 to 0.11. Because adequate models varying in carbon, nitrogen, and oxygen are not presently available, we …

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Book Review: How Do You Find An Exoplanet?, T. D. Oswalt Sep 2016

Book Review: How Do You Find An Exoplanet?, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of How Do You Find an Exoplanet? by John Asher Johnson. Princeton, 2016 178p bibl index afp, 9780691156811 $35.00, 9781400873999

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New Halo White Dwarf Candidates In The Sloan Digital Sky Survey, Kyra Dame, A. Gianninas, Mukremin Kilic, Jeffrey A. Munn, Warren R. Brown, Kurtis A. Williams, Ted Von Hippel, Hugh C. Harris Aug 2016

New Halo White Dwarf Candidates In The Sloan Digital Sky Survey, Kyra Dame, A. Gianninas, Mukremin Kilic, Jeffrey A. Munn, Warren R. Brown, Kurtis A. Williams, Ted Von Hippel, Hugh C. Harris

Publications

We present optical spectroscopy and near-infrared photometry of 57 faint (g = 19–22) high proper motion white dwarfs identified through repeat imaging of ≈3100 deg2 of the Sloan Digital Sky Survey footprint by Munn et al. We use ugriz and JHphotometry to perform a model atmosphere analysis, and identify 10 ultracool white dwarfs with Teff < 4000 K, including the coolest pure H atmosphere white dwarf currently known, J1657+2638, with Teff = 3550 ± 100 K. The majority of the objects with cooling ages larger than 9 Gyr display thick disc kinematics and constrain the age of the thick disc to ≥11 Gyr. There are four white dwarfs in our sample with …

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Combined Search For Lorentz Violation In Short-Range Gravity, Cheng-Gang Shao, Yu-Jie Tan, Wen-Hai Tan, Shan-Qing Yang, Jun Luo, Michael Edmund Tobar, Quentin G. Bailey, Et Al. Aug 2016

Combined Search For Lorentz Violation In Short-Range Gravity, Cheng-Gang Shao, Yu-Jie Tan, Wen-Hai Tan, Shan-Qing Yang, Jun Luo, Michael Edmund Tobar, Quentin G. Bailey, Et Al.

Publications

Short-range experiments testing the gravitational inverse-square law at the submillimeter scale offer uniquely sensitive probes of Lorentz invariance. (See article for remainder of abstract.)

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Cytoplasmic Dynein Binding, Run Length, And Velocity Are Guided By Long-Range Electrostatic Interactions, Lin Li, Joshua Alper, Emil Alexov Aug 2016

Cytoplasmic Dynein Binding, Run Length, And Velocity Are Guided By Long-Range Electrostatic Interactions, Lin Li, Joshua Alper, Emil Alexov

Publications

Dyneins are important molecular motors involved in many essential biological processes, including cargo transport along microtubules, mitosis, and in cilia. Dynein motility involves the coupling of microtubule binding and unbinding to a change in the configuration of the linker domain induced by ATP hydrolysis, which occur some 25 nm apart. This leaves the accuracy of dynein stepping relatively inaccurate and susceptible to thermal noise. Using multi-scale modeling with a computational focusing technique, we demonstrate that the microtubule forms an electrostatic funnel that guides the dynein’s microtubule binding domain (MTBD) as it finally docks to the precise, keyed binding location on …

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Current Sheet Flapping Motions In The Tailwind Flow Of Magnetic Reconnection, Mingyu Wu, Quanming Lu, Martin Volwerk, Zoltán Vörös, Xuanye Ma, Shui Wang Aug 2016

Current Sheet Flapping Motions In The Tailwind Flow Of Magnetic Reconnection, Mingyu Wu, Quanming Lu, Martin Volwerk, Zoltán Vörös, Xuanye Ma, Shui Wang

Publications

The feature and origin of current sheet flapping motions are one of most interesting issues of magnetospheric dynamics. In this paper we report the flapping motion of the current sheet detected in the tailward flow of a magnetic reconnection event on 7 February 2009. This flapping motion with frequency about 12 mHz was accompanied by magnetic turbulence. The observations by the tail‐elongated fleet of five Time History of Events and Macroscale Interactions during Substorms probes indicate that these flapping oscillations were rather confined within the tailward flow than were due to a global process. This flapping motion could be due …

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Completeness Of The Nearby White Dwarf Sample: Let Us Count The Ways, Terry D. Oswalt, Jay Holberg, Edward M. Sion Jul 2016

Completeness Of The Nearby White Dwarf Sample: Let Us Count The Ways, Terry D. Oswalt, Jay Holberg, Edward M. Sion

Publications

We have recently extended our ongoing survey of the local white dwarf population, effectively doubling the sample volume. Based upon the latest distance determinations, Holberg et al. (2016) estimated the present 20 pc and 25 pc samples were about 86 and 68 percent complete, respectively. Here we examine how the completeness of the 25 pc sample depends upon other observables such as apparent magnitude, proper motion, photometric color index, etc. The results may provide additional clues to why “Sirius-Like systems” are underrepresented in the extended 25 pc sample and how additional nearby single white dwarf stars may be found.

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Plasma Transport Driven By The Rayleigh-Taylor Instability, X. Ma, P. A. Delamere, A. Otto Jun 2016

Plasma Transport Driven By The Rayleigh-Taylor Instability, X. Ma, P. A. Delamere, A. Otto

Publications

Two important differences between the giant magnetospheres (i.e., Jupiter's and Saturn's magnetospheres) and the terrestrial magnetosphere are the internal plasma sources and the fast planetary rotation. Thus, there must be a radially outward flow to transport the plasma to avoid infinite accumulation of plasma. This radial outflow also carries the magnetic flux away from the inner magnetosphere due to the frozen‐in condition. As such, there also must be a radial inward flow to refill the magnetic flux in the inner magnetosphere. Due to the similarity between Rayleigh‐Taylor (RT) instability and the centrifugal instability, we use a three‐dimensional RT instability to …

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Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5 σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 …

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Observing Gravitational-Wave Transient Gw150914 With Minimal Assumptions, B. P. Abbott, K. Gill, B. Hughey, M. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Observing Gravitational-Wave Transient Gw150914 With Minimal Assumptions, B. P. Abbott, K. Gill, B. Hughey, M. Szczepańczyk, M. Zanolin, Et Al.

Publications

The gravitational-wave signal GW150914 was first identified on September 14, 2015, by searches for short-duration gravitational-wave transients. These searches identify time-correlated transients in multiple detectors with minimal assumptions about the signal morphology, allowing them to be sensitive to gravitational waves emitted by a wide range of sources including binary black hole mergers. Over the observational period from September 12 to October 20, 2015, these transient searches were sensitive to binary black hole mergers similar to GW150914 to an average distance of ∼600  Mpc. In this paper, we describe the analyses that first detected GW150914 as well as the parameter estimation …

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Characterization Of Transient Noise In Advanced Ligo Relevant To Gravitational Wave Signal Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Characterization Of Transient Noise In Advanced Ligo Relevant To Gravitational Wave Signal Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

On September 14, 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal.

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Gravity Sector Of The Sme, Q. G. Bailey Jun 2016

Gravity Sector Of The Sme, Q. G. Bailey

Publications

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.

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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 Jun 2016

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

Publications

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 transformation from …

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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. Jun 2016

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.

Publications

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.

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Prospects For Sme Tests With Experiments At Syrte And Lkb, C. Guerlin, H. Pihan-Le Bars, Q. G. Bailey, P. Wolf Jun 2016

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

Publications

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.

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