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Articles 1021 - 1050 of 2945

Full-Text Articles in Astrophysics and Astronomy

The Limited Reign Of Saturn's Rings, Laurence A. Marschall Mar 2019

The Limited Reign Of Saturn's Rings, Laurence A. Marschall

Physics and Astronomy Faculty Publications

Saturn’s rings—stretching tens of thousands of miles above its equator but no more than a few hundred yards thick—mark an ancient debris field of orbiting ice shards, the remains of a moon-sized object that strayed too close and was torn to pieces by Saturn’s intense gravitation. Astronomers have debated when the rings formed and how long they will stay in orbit. Recent observations from large, land-based telescopes and orbiting spacecraft reveal that Saturn’s rings are remarkably young and are dissipating at a rapid rate. [excerpt]

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Taller In The Saddle: Constraining Cmb Physics Using Saddle Points, Jow L. Dylan, Dagoberto Contreras, Douglas Scott, Emory F. Bunn Mar 2019

Taller In The Saddle: Constraining Cmb Physics Using Saddle Points, Jow L. Dylan, Dagoberto Contreras, Douglas Scott, Emory F. Bunn

Physics Faculty Publications

The statistics of extremal points in the cosmic microwave background (CMB) temperature (hot and cold spots) have been well explored in the literature, and have been used to constrain models of the early Universe. Here, we extend the study of critical points in the CMB to the set that remains after removing extrema, namely the saddle points. We perform stacks of temperature and polarization about temperature saddle points in simulations of the CMB, as well as in data from the Plancksatellite. We then compute the theoretical profile of saddle-point stacks, given the underlying power spectra of the CMB. As an …

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Kondo Signatures Of A Quantum Magnetic Impurity In Topological Superconductors, Rui Wang, Wei-Yi Su, Jian-Xin Zhu, Chin-Sen Ting, Hai Li, Changfeng Chen, Baigeng Wang, Xiaoqun Wang Mar 2019

Kondo Signatures Of A Quantum Magnetic Impurity In Topological Superconductors, Rui Wang, Wei-Yi Su, Jian-Xin Zhu, Chin-Sen Ting, Hai Li, Changfeng Chen, Baigeng Wang, Xiaoqun Wang

Physics & Astronomy Faculty Research

We study the Kondo physics of a quantum magnetic impurity in two-dimensional topological superconductors (TSCs), either intrinsic or induced on the surface of a bulk topological insulator, using a numerical renormalization group technique. We show that, despite sharing the p+ip pairing symmetry, intrinsic and extrinsic TSCs host different physical processes that produce distinct Kondo signatures. Extrinsic TSCs harbor an unusual screening mechanism involving both electron and orbital degrees of freedom that produces rich and prominent Kondo phenomena, especially an intriguing pseudospin Kondo singlet state in the superconducting gap and a spatially anisotropic spin correlation. In sharp contrast, intrinsic TSCs support …

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Simulations Of Microscopic Propulsion Of Soft Elastic Bodies, David Urbanik, Shikhar Man Dwivedi, Colin Denniston Feb 2019

Simulations Of Microscopic Propulsion Of Soft Elastic Bodies, David Urbanik, Shikhar Man Dwivedi, Colin Denniston

Physics and Astronomy Publications

Using simulations that realistically model both hydrodynamic and elastic behavior, we study the motion of a microscopic, driven elastic sphere immersed in water. We first confirm the “jittery” relaxation recently predicted theoretically for an externally driven elastic sphere. The sphere is then divided in two and each section is driven internally with the two sections 180° out of phase. With periodic and perfectly symmetric driving, the elastic sphere spontaneously breaks symmetry and can attain macroscopic average swimming velocities to the right or left, the direction depending only on the initial state. With asymmetric driving the elastic sphere swims in one …

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A Concept Of Biopharmaceutical Nanosatellite, Jakub Mielczarek, Adam Zadrozny Feb 2019

A Concept Of Biopharmaceutical Nanosatellite, Jakub Mielczarek, Adam Zadrozny

Physics & Astronomy Faculty Publications

The article is a short overview of a proposal of a CubeSat type nanosatellite designed to conduct biopharmaceutical tests on the low earth orbit. Motivations behind the emerging demand for such solution nowadays and in the close future are emphasized. The possible objectives and challenges to be addressed in the planned biopharmaceutical CubeSat missions are discussed. In particular, it is hard to imagine progress of the space tourism and colonization of Mars without a wide-ranging development of pharmaceutics dedicated to be used in space. Finally, an exemplary layout of a 3U type CubeSat is presented. We stress that, thanks to …

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Wallaby Early Science – Ii. The Ngc 7232 Galaxy Group, K. Lee-Waddell, Bärbel S. Koribalski, Tobias Westmeier, A. Elagali, B-Q For, D. Kleiner, Juan P. Madrid, A. Popping, T. N. Reynolds, J. Rhee Jan 2019

Wallaby Early Science – Ii. The Ngc 7232 Galaxy Group, K. Lee-Waddell, Bärbel S. Koribalski, Tobias Westmeier, A. Elagali, B-Q For, D. Kleiner, Juan P. Madrid, A. Popping, T. N. Reynolds, J. Rhee

Physics & Astronomy Faculty Publications

We report on neutral hydrogen (H I) observations of the NGC 7232 group with the Australian Square Kilometre Array Pathfinder (ASKAP). These observations were conducted as part of the Wide-field ASKAP L-Band Legacy All-sky Blind surveY (WALLABY) Early Science program with an array of 12 ASKAP antennas equipped with Phased Array Feeds, which were used to form 36 beams to map a field of view of 30 deg2. Analysing a subregion of the central beams, we detect 17 H I sources. Eleven of these detections are identified as galaxies and have stellar counterparts, of which five are newly resolved H …

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Results From The Cuore Experiment †, Alessio Caminata, Douglas Adams, Chris Alduino, Krystal Alfonso, Frank Avignone Iii, Oscar Azzolini, Giacomo Bari, Fabio Bellini, Giovanni Benato, Andrea Bersani, Matteo Biassoni, Antonio Branca, Chiara Brofferio, Carlo Bucci, Alice Campani, Lucia Canonica, Xi-Guang Cao, Silvia Capelli, Luigi Cappelli, Laura Cardani, Paolo Carniti, Et. Al. Jan 2019

Results From The Cuore Experiment †, Alessio Caminata, Douglas Adams, Chris Alduino, Krystal Alfonso, Frank Avignone Iii, Oscar Azzolini, Giacomo Bari, Fabio Bellini, Giovanni Benato, Andrea Bersani, Matteo Biassoni, Antonio Branca, Chiara Brofferio, Carlo Bucci, Alice Campani, Lucia Canonica, Xi-Guang Cao, Silvia Capelli, Luigi Cappelli, Laura Cardani, Paolo Carniti, Et. Al.

Faculty Publications

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers, each of them made of 52 crystals. The construction of the experiment was completed in August 2016 and the data taking started in spring 2017 after a period of commissioning and tests. In this work we present the neutrinoless double beta decay results of CUORE from examining a total TeO2 exposure …

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Analytic Modeling Of Eccentric Binary Black Holes : From Inspiral To Merger, Dillon Paige Buskirk Jan 2019

Analytic Modeling Of Eccentric Binary Black Holes : From Inspiral To Merger, Dillon Paige Buskirk

Theses, Dissertations and Capstones

The orbital evolution of black hole binaries is described by two main phases: the inspiral and the merger. Using the post-Newtonian (PN) theory for the inspiral phase of the binary, we build up a Mathematica script to obtain strain waveforms for the inspiral. We expand our previous inspiral formulation to include eccentric orbits, which greatly complicates the calculations. Since this model breaks down as the two bodies approach merger, a separate model for the merger and ring-down is required. This part of the evolution is highly non-linear and numerical relativity (NR) is required to simulate this problem. However, this is …

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Ua66/11/1 Ogden College Of Science & Engineering Physics & Astronomy Publications, Wku Archives Jan 2019

Ua66/11/1 Ogden College Of Science & Engineering Physics & Astronomy Publications, Wku Archives

WKU Archives Collection Inventories

Publications by and about the Department of Physics and Astronomy.

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Principal Component Analysis Of The Magnetic Transition In The Three-Dimensional Fermi-Hubbard Model, Ehsan Khatami Jan 2019

Principal Component Analysis Of The Magnetic Transition In The Three-Dimensional Fermi-Hubbard Model, Ehsan Khatami

Faculty Publications

Machine learning techniques have been widely used in the study of strongly correlated systems in recent years. Here, we review some applications to classical and quantum many-body systems and present results from an unsupervised machine learning technique, the principal component analysis, employed to identify the finite-temperature phase transition of the three-dimensional Fermi-Hubbard model to the antiferromagnetically ordered state. We find that this linear method can capture the phase transition as well as other more complicated and nonlinear counterparts.

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Spacetime Groups, Ian M. Anderson, Charles G. Torre Jan 2019

Spacetime Groups, Ian M. Anderson, Charles G. Torre

Publications

A spacetime group is a connected 4-dimensional Lie group G endowed with a left invariant Lorentz metric h and such that the connected component of the isometry group of h is G itself. The Newman-Penrose formalism is used to give an algebraic classification of spacetime groups, that is, we determine a complete list of inequivalent spacetime Lie algebras, which are pairs (g,η), with g being a 4-dimensional Lie algebra and η being a Lorentzian inner product on g. A full analysis of the equivalence problem for spacetime Lie algebras is given which leads to a completely algorithmic solution to the …

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Ua66/11/3 Ogden College Of Science & Engineering Physics & Astronomy Student Organizations, Wku Archives Jan 2019

Ua66/11/3 Ogden College Of Science & Engineering Physics & Astronomy Student Organizations, Wku Archives

WKU Archives Collection Inventories

Records created by and about student organizations associated with the Physics and Astronomy.

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Ua66/11/2 Ogden College Of Science & Engineering Physics & Astronomy Administration, Wku Archives Jan 2019

Ua66/11/2 Ogden College Of Science & Engineering Physics & Astronomy Administration, Wku Archives

WKU Archives Collection Inventories

Records created by and about the administration of Physics and Astronomy.

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Electrical Detection Of Current Generated Spin In Topological Insulator Surface States: Role Of Interface Resistance, C. H. Li, O. M. J. Van ‘T Erve, C. Yan, L. Li., B. T. Jonker Jan 2019

Electrical Detection Of Current Generated Spin In Topological Insulator Surface States: Role Of Interface Resistance, C. H. Li, O. M. J. Van ‘T Erve, C. Yan, L. Li., B. T. Jonker

Faculty & Staff Scholarship

Current generated spin polarization in topological insulator (TI) surface states due to spin-momentum locking has been detected recently using ferromagnet/tunnel barrier contacts, where the projection of the TI spin onto the magnetization of the ferromagnet is measured as a voltage. However, opposing signs of the spin voltage have been reported, which had been tentatively attributed to the coexistence of trivial two-dimensional electron gas states on the TI surface which may exhibit opposite currentinduced polarization than that of the TI Dirac surface states. Models based on electrochemical potential have been presented to determine the sign of the spin voltage expected for …

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Reply To: “On The Understanding Of Current-Induced Spin Polarization Of Three-Dimensional Topological Insulators”, C. H. Li, O. M. J. Van ‘T Erve, S. Rajput, L. Li, B. T. Jonker Jan 2019

Reply To: “On The Understanding Of Current-Induced Spin Polarization Of Three-Dimensional Topological Insulators”, C. H. Li, O. M. J. Van ‘T Erve, S. Rajput, L. Li, B. T. Jonker

Faculty & Staff Scholarship

No abstract provided.

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Exploring The Structure Of Misconceptions In The Force Concept Inventory With Modified Module Analysis, James Wells, Rachel Henderson, John Stewart, Gay Stewart, Jie Yang, Adrienne Traxler Jan 2019

Exploring The Structure Of Misconceptions In The Force Concept Inventory With Modified Module Analysis, James Wells, Rachel Henderson, John Stewart, Gay Stewart, Jie Yang, Adrienne Traxler

Faculty & Staff Scholarship

Module analysis for multiple-choice responses (MAMCR) was applied to a large sample of Force Concept Inventory (FCI) pretest and post-test responses (Npre ¼ 4509 and Npost ¼ 4716) to replicate the results of the original MAMCR study and to understand the origins of the gender differences reported in a previous study of this dataset. When the results of MAMCR could not be replicated, a modification of the method was introduced, modified module analysis (MMA). MMA was productive in understanding the structure of the incorrect answers in the FCI, identifying 9 groups of incorrect answers on the pretest and 11 groups …

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The Undeniable Attraction Of Lunar Swirls, Dany Waller Jan 2019

The Undeniable Attraction Of Lunar Swirls, Dany Waller

Posters-at-the-Capitol Presentations

Lunar swirls are complex patterns on the Moon with distinct brightness signatures and magnetic characteristics. Current research has suggested that the formation of lunar swirls relies on local magnetic fields to shield impinging solar wind, based on a shift in electromagnetic wavelength peaks related to solar radiation and space weathering. Our research combined recent models and methods to characterize these anomalies at the surface of the Moon, exploring the effects of field strength and position. We have produced a high resolution map of a famous swirl named Reiner Gamma using magnetic dipole modeling. These maps and models are considered when …

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Tuning The Reactivity Of Nanoenergetic Gas Generators Based On Bismuth And Iodine Oxidizers, Mkhitar A. Hobosyan, Karen S. Martirosyan Jan 2019

Tuning The Reactivity Of Nanoenergetic Gas Generators Based On Bismuth And Iodine Oxidizers, Mkhitar A. Hobosyan, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

There is a growing interest on novel energetic materials called Nanoenergetic Gas- Generators (NGGs) which are potential alternatives to traditional energetic materials including pyrotechnics, propellants, primers and solid rocket fuels. NGGs are formulations that utilize metal powders as a fuel and oxides or hydroxides as oxidizers that can rapidly release large amount of heat and gaseous products to generate shock waves. The heat and pressure discharge, impact sensitivity, long term stability and other critical properties depend on the particle size and shape, as well as assembling procedure and intermixing degree between the components. The extremely high energy density and the …

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Determination Of Multi-Messenger Signals From Matter Outflows Of Merger Systems, Ronny Nguyen Jan 2019

Determination Of Multi-Messenger Signals From Matter Outflows Of Merger Systems, Ronny Nguyen

Honors Theses and Capstones

In 2017, LIGO detected gravitational waves from GW170817. This presented for the first time, gravitational waves originating from a neutron star - neutron star merger. Studies of neutron star mergers are significant because the multi-messenger signals in the form of gravitational waves and electromagnetic waves can inform us on the nuclear physics of neutron stars and the creation of heavy elements in the universe. Matter is ejected in the merging process and forms the outflow which provides a neutron-rich environment for rapid neutron capture (r-process) to occur leading to the nucleosynthesis of heavy elements. What we detect on Earth are …

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Asteroid Surfaces: The Importance Of Cohesive Forces, Keanna Jardine Jan 2019

Asteroid Surfaces: The Importance Of Cohesive Forces, Keanna Jardine

Electronic Theses and Dissertations

Adhesive forces play a significant role on airless bodies due to their weak gravities. Investigating adhesion at the surface of asteroids and their constituent components is vital to understanding their formation and evolution. Previous research has been done to understand the interaction of micron-sized spheres to planar surfaces and sphere-to-sphere interactions, which have been used to develop models of asteroid surfaces. Our investigation experimentally investigates adhesion through atomic force microscopy (AFM) measurements between JSC-1 simulant particles and several AFM tips, including a typical pyramidal gold tip and microspheres of sizes 2 μm and 15 μm. The samples of JSC-1 consist …

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Application Of Wavelet Analysis On Transient Rlectivity In Ultra-Thin Films, S. Yousefi Saraf, R. Trappen, S. Kumari, G. Bhandari, N. Mottaghi, C. Y. Huang, G. B. Cabrera, A. D. Bristow, M. B. Holcomb Jan 2019

Application Of Wavelet Analysis On Transient Rlectivity In Ultra-Thin Films, S. Yousefi Saraf, R. Trappen, S. Kumari, G. Bhandari, N. Mottaghi, C. Y. Huang, G. B. Cabrera, A. D. Bristow, M. B. Holcomb

Faculty & Staff Scholarship

Applications of wavelet analysis in ultra-thin film transient reflectivity (TR) measurements have been investigated. Advantages of utilizing different localized wavelet bases, in position and time, have been addressed on the residual TR signals. Morse wavelets have been used to obtain information from the abrupt oscillatory modes in the signal, which are not distinguishable with conventional methods such as Fourier transforms. These abrupt oscillatory modes are caused by the surface, interface, or any short-lived oscillatory modes which are suppressed in the TR signal in ultra-thin films. It is demonstrated that by choosing different Morse wavelets, information regarding different oscillatory modes in …

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Multidimensional Item Response Theory And The Force And Motion Conceptual Evaluation, Jie Yang, Cabot Zabriskie, John Stewart Jan 2019

Multidimensional Item Response Theory And The Force And Motion Conceptual Evaluation, Jie Yang, Cabot Zabriskie, John Stewart

Faculty & Staff Scholarship

Many studies have examined the structure and properties of the Force Concept Inventory (FCI); however, far less research has investigated the Force and Motion Conceptual Evaluation (FMCE). This study applied Multidimensional Item Response Theory (MIRT) to a sample of N ¼ 4528 FMCE post-test responses. Exploratory factor analysis showed that 5, 9, and 10-factor models optimized some fit statistics. The FMCE uses extensive blocking of items into groups with a common stem; these blocks factored together in most models. A confirmatory analysis, which constrained the MIRT models to a theoretical model constructed from expert solutions, produced a model requiring only …

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Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott Jan 2019

Testing For Directionality In The Planck Polarization And Lensing Data, Majd Ghrear, Emory F. Bunn, Dagoberto Contreras, Douglas Scott

Physics Faculty Publications

In order to better analyse the polarization of the cosmic microwave background (CMB), which is dominated by emission from our Galaxy, we need tools that can detect residual foregrounds in cleaned CMB maps. Galactic foregrounds introduce statistical anisotropy and directionality to the polarization pseudo-vectors of the CMB, which can be investigated by using the D statistic of Bunn and Scott. This statistic is rapidly computable and capable of investigating a broad range of data products for directionality. We demonstrate the application of this statistic to detecting foregrounds in polarization maps by analysing the uncleaned Planck 2018 frequency maps. For the …

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Multidimensional Item Response Theory And The Conceptual Survey Of Electricity And Magnetism, Cabot Zabriskie, John Stewart Jan 2019

Multidimensional Item Response Theory And The Conceptual Survey Of Electricity And Magnetism, Cabot Zabriskie, John Stewart

Faculty & Staff Scholarship

This paper is part of the Focused Collection on Quantitative Methods in PER: A Critical Examination.] While many studies have examined the structure, validity, and reliability of the Force Concept Inventory, far less research has been performed on other conceptual instruments in widespread use in physics education research. This study performs a confirmatory analysis of the Conceptual Survey of Electricity and Magnetism (CSEM) guided by a theoretical model of expert understanding of electricity and magnetism. Multidimensional Item Response Theory (MIRT) with the discrimination matrix constrained to the theoretical model was used to investigate two large datasets (N1=2014 and N2=2657) from …

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Partitioning The Gender Gap In Physics Conceptual Inventories: Force Concept Inventory, Force And Motion Conceptual Evaluation, And Conceptual Survey Of Electricity And Magnetism, Rachel Henderson, John Stewart, Adrienne Traxler Jan 2019

Partitioning The Gender Gap In Physics Conceptual Inventories: Force Concept Inventory, Force And Motion Conceptual Evaluation, And Conceptual Survey Of Electricity And Magnetism, Rachel Henderson, John Stewart, Adrienne Traxler

Faculty & Staff Scholarship

Over the last decade, the “gender gap” in physics conceptual inventory scores has been extensively studied by the physics education research community. Researchers have identified many factors that influence the overall differences in post-test scores between men and women. More recently, it has been shown that the Force Concept Inventory (FCI) contains eight items that are substantially unfair; six are unfair to women, two are unfair to men. The Force and Motion Conceptual Evaluation (FMCE) and the Conceptual Survey of Electricity and Magnetism (CSEM), however, contain fewer unfair items. In this work, results from prior studies are used to further …

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Interface Engineered Room‐Temperature Ferromagnetic Insulating State In Ultrathin Manganite Films, Weiwei Li, Bonan Zhu, Qian He, Albina Y. Borisevich, Chao Yun, Rui Wu, Ping Lu, Zhimin Qi, Qiang Wang, Aiping Chen, Haiyan Wang, Stuart A. Cavill, Kelvin H.L. Zhang, Judith L. Macmanus-Driscoll Jan 2019

Interface Engineered Room‐Temperature Ferromagnetic Insulating State In Ultrathin Manganite Films, Weiwei Li, Bonan Zhu, Qian He, Albina Y. Borisevich, Chao Yun, Rui Wu, Ping Lu, Zhimin Qi, Qiang Wang, Aiping Chen, Haiyan Wang, Stuart A. Cavill, Kelvin H.L. Zhang, Judith L. Macmanus-Driscoll

Faculty & Staff Scholarship

emperatures near room temperature are critically needed for use in dissipationless quantum computation and spintronic devices. However, such materials are extremely rare. Here, a room‐temperature FMI is achieved in ultrathin La0.9Ba0.1MnO3 films grown on SrTiO3 substrates via an interface proximity effect. Detailed scanning transmission electron microscopy images clearly demonstrate that MnO6 octahedral rotations in La0.9Ba0.1MnO3 close to the interface are strongly suppressed. As determined from in situ X‐ray photoemission spectroscopy, O K‐edge X‐ray absorption spectroscopy, and density functional theory, the realization of the FMI state arises from a reduction of Mn eg bandwidth caused by the quenched MnO6 octahedral …

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Automated Polarization-Dependent Multidimensional Coherent Spectroscopy Phased Using Transient Absorption, J. K. Wahlstrand, G. M. Wernsing, J. Paul, A. D. Bristow Jan 2019

Automated Polarization-Dependent Multidimensional Coherent Spectroscopy Phased Using Transient Absorption, J. K. Wahlstrand, G. M. Wernsing, J. Paul, A. D. Bristow

Faculty & Staff Scholarship

: An experimental apparatus is described for multidimensional optical spectroscopy with fully automated polarization control, based on liquid crystal variable retarders. Polarization dependence of rephasing two-dimensional coherent spectra are measured in a single scan, with absolute phasing performed for all polarization configurations through a single automated auxiliary measurement at the beginning of the scan. A factor of three improvement in acquisition time is demonstrated, compared to the apparatus without automated polarization control. Results are presented for a GaAs quantum well sample and an InGaAs quantum well embedded in a microcavity

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Micro/Nanofabrication And Characterization Of Advanced Materials And Devices, Yanxi Li, Liang He, Mengyu Yan, Zhengjun Wang Jan 2019

Micro/Nanofabrication And Characterization Of Advanced Materials And Devices, Yanxi Li, Liang He, Mengyu Yan, Zhengjun Wang

Faculty & Staff Scholarship

No abstract provided.

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All-Sky Search For Long-Duration Gravitational-Wave Transients In The Second Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny Jan 2019

All-Sky Search For Long-Duration Gravitational-Wave Transients In The Second Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny

Physics & Astronomy Faculty Publications

We present the results of a search for long-duration gravitational-wave transients in the data from the Advanced LIGO second observation run; we search for gravitational-wave transients of 2–500 s duration in the 24–2048 Hz frequency band with minimal assumptions about signal properties such as waveform morphologies, polarization, sky location or time of occurrence. Signal families covered by these search algorithms include fallback accretion onto neutron stars, broadband chirps from innermost stable circular orbit waves around rotating black holes, eccentric inspiral-merger-ringdown compact binary coalescence waveforms, and other models. The second observation run totals about 118.3 days of coincident data between November …

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Narrow-Band Search For Gravitational Waves From Known Pulsars Using The Second Ligo Observing Run, B. P. Abbott, B. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, A. K. Zadrozny Jan 2019

Narrow-Band Search For Gravitational Waves From Known Pulsars Using The Second Ligo Observing Run, B. P. Abbott, B. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, A. K. Zadrozny

Physics & Astronomy Faculty Publications

Isolated spinning neutron stars, asymmetric with respect to their rotation axis, are expected to be sources of continuous gravitational waves. The most sensitive searches for these sources are based on accurate matched filtering techniques that assume the continuous wave to be phase locked with the pulsar beamed emission. While matched filtering maximizes the search sensitivity, a significant signal-to-noise ratio loss will happen in the case of a mismatch between the assumed and the true signal phase evolution. Narrowband algorithms allow for a small mismatch in the frequency and spin-down values of the pulsar while coherently integrating the entire dataset. In …

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