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Design And Evaluation Of 3d-Printed Filar Micrometer, Emily Rull 2018 Olivet Nazarene University

Design And Evaluation Of 3d-Printed Filar Micrometer, Emily Rull

Scholar Week 2016 - present

This project sought to design and 3D-print a filar micrometer for double star measurements that amateur astronomers could produce cost effectively.

Double stars are celestial objects that allow the mass of stars to be calculated by assessing their orbits. Stellar mass affects every current model of stellar evolution, but the most accurate double star orbits can take decades to record. As a result of the long-term nature of such observations and lack of groundbreaking research in double star studies, professional astronomers are no longer focused on making these measurements. This allows amateur astronomers to pick up where professionals have left ...


The Subject Librarian Newsletter, Nanoscience, Fall 2016, Sandy Avila 2018 University of Central Florida

The Subject Librarian Newsletter, Nanoscience, Fall 2016, Sandy Avila

Sandy Avila

No abstract provided.


"Water Fountain" Masers In Proto-Planetary Nebulae, Patrick R. Latimer 2018 University of New Mexico

"Water Fountain" Masers In Proto-Planetary Nebulae, Patrick R. Latimer

Jim & Mary Lois Hulsman Undergraduate Library Research Award

No abstract provided.


Gravity Then And Now, Paul Ingraham 2018 Germanna Community College

Gravity Then And Now, Paul Ingraham

Student Writing

This paper discusses the theory of gravity from the time it was discovered by Sir Isaac Newton to present time with the discovery of gravitational waves by Albert Einstein, and the detection of gravitational waves. Stephen Hawking's and Leonard Mlodinow's recent book, The Grand Design, provides support for Edward Witten's M-theory. Gravity was the first of the four fundamental forces to be discovered, and that last to be detected. Einstein proposed that gravity was not only a force, but also could be characterized as a wave on the space-time continuum.


An Enigmatic Population Of Luminous Globular Clusters In A Galaxy Lacking Dark Matter, Pieter van Dokkum, Yotam Cohen, Shany Danieli, J. Diederik Kruijssen, Aaron Romanowsky, Allison Merritt, Roberto Abraham, Jean Brodie, Charlie Conroy, Deborah Lokhorst, Lamiya Mowla, Ewan O'Sullivan, Jielai Zhang 2018 Yale University

An Enigmatic Population Of Luminous Globular Clusters In A Galaxy Lacking Dark Matter, Pieter Van Dokkum, Yotam Cohen, Shany Danieli, J. Diederik Kruijssen, Aaron Romanowsky, Allison Merritt, Roberto Abraham, Jean Brodie, Charlie Conroy, Deborah Lokhorst, Lamiya Mowla, Ewan O'Sullivan, Jielai Zhang

Faculty Publications

We recently found an ultra diffuse galaxy (UDG) with a half-light radius of R e = 2.2 kpc and little or no dark matter. The total mass of NGC1052–DF2 was measured from the radial velocities of bright compact objects that are associated with the galaxy. Here, we analyze these objects using a combination of Hubble Space Telescope (HST) imaging and Keck spectroscopy. Their average size is pc and their average ellipticity is . From a stacked Keck spectrum we derive an age of 9 Gyr and a metallicity of [Fe/H] = −1.35 ± 0.12. Their properties are similar to ...


Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman 2018 International Islamic University - Malaysia

Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

Experiments on the relative merits and demerits of slotted wingtips mimicking a bird’s primary feathers have been performed. The real emargination length of feather tips, their flexibility and curved shapes during cruise are considered in the present study. The experiments were performed at a Reynolds number of 3.7 x 105 on a symmetric flat plate half wing of aspect ratio 3. Lift, drag and pitching moments were measured using a six component aerodynamic balance. Four different shapes inspired by bird primary feathers have been analysed. The rigid curved tip performed the best increasing the L/D ratio ...


Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna 2018 Wesleyan University

Multivariate Spectral Analysis Of Crism Data To Characterize The Composition Of Mawrth Vallis, Melissa Luna

Melissa Luna

No abstract provided.


Line Lists For Lif And Licl In The X1Σ+ Ground State, Dror M. Bittner, Peter F. Bernath 2018 Old Dominion University

Line Lists For Lif And Licl In The X1Σ+ Ground State, Dror M. Bittner, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Vibration–rotation line lists for 6LiF, 7LiF, 6Li35Cl, 6Li37Cl, 7Li35Cl, and 7Li37Cl in the X1Σ+ ground states have been prepared. The rovibrational energy levels have been calculated using potential energy surfaces determined by direct potential-fitting employing the rotational and rovibrational transition frequencies of all isotopologues, and required the inclusion of Born–Oppenheimer breakdown terms. Dipole moment functions calculated ab initio at the MRCI/aug-cc-pwCV5Z level have been used for line strength calculations. Partition functions for temperatures up to 5000 K have been calculated. LiF ...


Improved Ultraviolet And Infrared Oscillator Strengths For Oh+, James N. Hodges, Dror M. Bittner, Peter F. Bernath 2018 Old Dominion University

Improved Ultraviolet And Infrared Oscillator Strengths For Oh+, James N. Hodges, Dror M. Bittner, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Molecular ions are key reaction intermediates in the interstellar medium. OH+ plays a central role in the formation of more complex chemical species and for estimating the cosmic ray ionization rate in astrophysical environments. Here, we use a recent analysis of a laboratory spectrum in conjunction with ab initio methods to calculate infrared and ultraviolet oscillator strengths. These new oscillator strengths include branch dependent intensity corrections, arising from the Herman–Wallis effect, that have not been included before. We estimate 10% total uncertainty in the UV and 6% total uncertainty in the IR for the oscillator strengths.


All-Sky Search For Long-Duration Gravitational Wave Transients In The First Advanced Ligo Observing Run, B. P. Abbott, K. Gill, B. Hughey, J. W. W. Pratt, E. Rhoades, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, et al. 2018 California Institute of Technology

All-Sky Search For Long-Duration Gravitational Wave Transients In The First Advanced Ligo Observing Run, B. P. Abbott, K. Gill, B. Hughey, J. W. W. Pratt, E. Rhoades, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present the results of a search for long-duration gravitational wave transients in the data of the LIGO Hanford and LIGO Livingston second generation detectors between and , with a total observational time of . The search targets gravitational wave transients of 10–500 s duration in a frequency band of 24–2048 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. No significant events were observed. As a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. We also show that the ...


Effects Of Data Quality Vetoes On A Search For Compact Binary Coalescences In Advanced Ligo's First Observing Run, B. P. Abbott, K. Gill, B. Hughey, J. Pratt, M. J. Szczepańczyk, M. Zanolin, et al. 2018 California Institute of Technology

Effects Of Data Quality Vetoes On A Search For Compact Binary Coalescences In Advanced Ligo's First Observing Run, B. P. Abbott, K. Gill, B. Hughey, J. Pratt, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

The first observing run of Advanced LIGO spanned 4 months, from 12 September 2015 to 19 January 2016, during which gravitational waves were directly detected from two binary black hole systems, namely GW150914 and GW151226. Confident detection of gravitational waves requires an understanding of instrumental transients and artifacts that can reduce the sensitivity of a search. Studies of the quality of the detector data yield insights into the cause of instrumental artifacts and data quality vetoes specific to a search are produced to mitigate the effects of problematic data. In this paper, the systematic removal of noisy data from analysis ...


Scientometric Study Of Research Productivity Of Aries, Nainital, Satish Kumar 2018 Bharathiar University, Coimbatore & IIT(ISM), Dhanbad

Scientometric Study Of Research Productivity Of Aries, Nainital, Satish Kumar

Library Philosophy and Practice (e-journal)

This paper describes scientometric study of research productivity of Scientists of Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital. The purpose of this study is to evaluate the research performance of ARIES, Nainital. For this study, the data is collected from Web of Science (WoS) bibliographical database for the period of 15 years from 2001-2015 and analyzed. 574 research paper has been published over 15 years of time in which 510 research publications are in referred journals and 64 research publications are in conferences, symposiums, bulletins etc. This paper identifies the scientists of ARIES those are active; the areas in ...


The Prospect Of Human Spiritual Unity Through The Cosmic Story, Philip Novak 2018 Department of Religion and Philosophy, Dominican University of California

The Prospect Of Human Spiritual Unity Through The Cosmic Story, Philip Novak

Collected Faculty and Staff Scholarship

Thomas Berry and Brian Swimme have noted that, “we seem to be moving beyond any religious expression so far known to the human into a meta-religious age that seems to be a new comprehensive context for all religions.” That “new comprehensive context” is of course now known as Big History -- a.k.a. the Evolutionary Epic, Universe Story, or New Cosmic Story—the astonishing contemporary synthesis of modern sciences that tells a coherent story of the evolution of the universe from the Big Bang 13.7 billion years ago to the present.

Yet with the notable exception of the writings ...


Metallic Mxenes: A New Family Of Materials For Flexible Triboelectric Nanogenerators, Yongchang Dong, Sai Sunil Kumar Mallineni, Kathleen Maleski, Herbert Behlow, Vadym N. Mochalin, Apparao M. Rao, Yury Gogosti, Ramakrishna Podila 2018 Clemson University

Metallic Mxenes: A New Family Of Materials For Flexible Triboelectric Nanogenerators, Yongchang Dong, Sai Sunil Kumar Mallineni, Kathleen Maleski, Herbert Behlow, Vadym N. Mochalin, Apparao M. Rao, Yury Gogosti, Ramakrishna Podila

Publications

Wearable and flexible electronics warrant the development of self-powered devices to circumvent the limitations imposed by traditional energy storage devices. Triboelectric nanogenerators (TENGs) that convert waste mechanical energy from human motion into electric power offer a solution. Highly electronegative and conducting TENG materials that support the generation of both large potential differences and high currents are imperative for effectively harvesting electric power from human muscle movements. Here, we demonstrate that two-dimensional MXenes (e.g., titanium carbide Ti3C2Tx, where Tx stands for surface functional groups such as -O, -OH, and -F) are a family of electrically conducting materials that are triboelectrically ...


First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, K. AultONeal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, et al. 2018 California Institute of Technology

First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present results from the first directed search for nontensorial gravitational waves. While general relativity allows for tensorial (plus and cross) modes only, a generic metric theory may, in principle, predict waves with up to six different polarizations. This analysis is sensitive to continuous signals of scalar, vector, or tensor polarizations, and does not rely on any specific theory of gravity. After searching data from the first observation run of the advanced LIGO detectors for signals at twice the rotational frequency of 200 known pulsars, we find no evidence of gravitational waves of any polarization. We report the first upper ...


Experiments With The Gravitational Constant, Vildyan Yanbikov 2018 Yanbikov Vildyan Shavkyatovich

Experiments With The Gravitational Constant, Vildyan Yanbikov

Vildyan Yanbikov

Описание эксперимента определяющий зависимость гравитационной постоянной массы, центра тяжести и расстояние до этого центра


On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan Forbes, Aaron Romanowsky, Joachim Janz, Christopher Dixon 2018 Swinburne University of Technology

On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan Forbes, Aaron Romanowsky, Joachim Janz, Christopher Dixon

Faculty Publications

In order to investigate the formation mechanisms of the rare compact elliptical (cE) galaxies, we have compiled a sample of 25 cEs with good SDSS spectra, covering a range of stellar masses, sizes and environments. They have been visually classified according to the interaction with their host, representing different evolutionary stages. We have included clearly disrupted galaxies, galaxies that despite not showing signs of interaction are located close to a massive neighbour (thus are good candidates for a stripping process), and cEs with no host nearby. For the latter, tidal stripping is less likely to have happened and instead they ...


On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan A. Forbes, Aaron J. Romanowsky, Joachim Janz, Christopher Dixon 2018 Swinburne University of Technology

On The Formation Mechanisms Of Compact Elliptical Galaxies, Anna Ferré-Mateu, Duncan A. Forbes, Aaron J. Romanowsky, Joachim Janz, Christopher Dixon

Aaron J. Romanowsky

In order to investigate the formation mechanisms of the rare compact elliptical (cE) galaxies, we have compiled a sample of 25 cEs with good SDSS spectra, covering a range of stellar masses, sizes and environments. They have been visually classified according to the interaction with their host, representing different evolutionary stages. We have included clearly disrupted galaxies, galaxies that despite not showing signs of interaction are located close to a massive neighbour (thus are good candidates for a stripping process), and cEs with no host nearby. For the latter, tidal stripping is less likely to have happened and instead they ...


Sdss-Iv Manga: Uncovering The Angular Momentum Content Of Central And Satellite Early-Type Galaxies, J. E. Greene, A. Leauthaud, E. Emsellem, J. Ge, A. Aragón-Salamanca, J. Greco, Y. -T. Lin, S. Mao, K. Masters, M. Merrifield, S. More, N. Okabe, D. P. Schneider, D. Thomas, D. A. Wake, K. Pan, D. Bizyaev, D. Oravetz, A. Simmons, Renbin Yan, F. van den Bosch 2018 Princeton University

Sdss-Iv Manga: Uncovering The Angular Momentum Content Of Central And Satellite Early-Type Galaxies, J. E. Greene, A. Leauthaud, E. Emsellem, J. Ge, A. Aragón-Salamanca, J. Greco, Y. -T. Lin, S. Mao, K. Masters, M. Merrifield, S. More, N. Okabe, D. P. Schneider, D. Thomas, D. A. Wake, K. Pan, D. Bizyaev, D. Oravetz, A. Simmons, Renbin Yan, F. Van Den Bosch

Physics and Astronomy Faculty Publications

We study 379 central and 159 satellite early-type galaxies with two-dimensional kinematics from the integral-field survey Mapping Nearby Galaxies at APO (MaNGA) to determine how their angular momentum content depends on stellar and halo mass. Using the Yang et al. group catalog, we identify central and satellite galaxies in groups with halo masses in the range 1012.5 h-1 M < M200b < 1015 h-1 M. As in previous work, we see a sharp dependence on stellar mass, in the sense that ~70% of galaxies with stellar mass M* > 1011 h-2 M tend to have ...


Integrated Multi-Terminal Devices Consisting Of Carbon Nanotube, Few-Layer Graphene Nanogaps And Few-Layer Graphene Nanoribbons Having Crystallographically Controlled Interfaces, Douglas R. Strachan, David P. Hunley 2018 University of Kentucky

Integrated Multi-Terminal Devices Consisting Of Carbon Nanotube, Few-Layer Graphene Nanogaps And Few-Layer Graphene Nanoribbons Having Crystallographically Controlled Interfaces, Douglas R. Strachan, David P. Hunley

Physics and Astronomy Faculty Patents

The present invention relates to atomically-thin channel materials with crystallographically uniform interfaces to atomically-thin commensurate graphene electrodes and/or nanoribbons separated by nanogaps that allow for nanoelectronics based on quantum transport effects and having significantly improved contact resistances.


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