Astrophysics and Astronomy Commons^™

Seeing And Hearing Parallel Computing, : Samuel Haileselassie, Ryan Vreeke, Joel C. Adams

Summer Research

Students can have a hard time understanding parallel computing and what is happening behind the scenes. TSGL is a C++ based, open-source graphic library that can visualize the concepts of multithreading and parallelization. Likewise, TSAL is an open-source audio library that can create sonification based on threaded programs. The visual and sound outputs helps to lower the learning curve for students when it comes to understanding parallel computing.

Fourier Transform Of The Continuous Gravitational Wave Signal, Sree Ram Valluri, V. Dergachev, X. Zhang, Farrukh Chishtie

Physics and Astronomy Publications

The direct detection of continuous gravitational waves from pulsars is a much anticipated discovery in the emerging field of multimessenger gravitational wave (GW) astronomy. Because putative pulsar signals are exceedingly weak large amounts of data need to be integrated to achieve desired sensitivity. Contemporary searches use ingenious ad hoc methods to reduce computational complexity. In this paper we provide analytical expressions for the Fourier transform of realistic pulsar signals. This provides description of the manifold of pulsar signals in the Fourier domain, used by many search methods. We analyze the shape of the Fourier transform and provide explicit formulas for …

Using Mesa To Test Our Theory Of Contact Binary Star Evolution, Lauren Henderson, Jenn Lau, Larry A. Molnar

Summer Research

A contact binary star system consists of two stars orbiting each other so closely that they share a common atmosphere. Nearly 1% of stars like our sun are contact binaries, yet there is not a comprehensive model of their lives. Our goal is to understand the formation, life, and explosive demise of these objects. This summer we did the first comprehensive calculations of contact binary lifetimes from when they first come into contact until they reach instability.

Toi-519 B: A Short-Period Substellar Object Around An M Dwarf Validated Using Multicolour Photometry And Phase Curve Analysis, H. Parviainen, E. Palle, M. R. Zapatero-Osorio, G. Nowak, A. Fukui, F. Murgas, N. Narita, K. G. Stassun, J. H. Livingston, K. A. Collins, D. Hidalgo Soto, V. J. S. Béjar, J. Korth, M. Monelli, P. Montanes Rodriguez, N. Casasayas-Barris, G. Chen, N. Crouzet, J. P. De Leon, A. Hernandez, K. Kawauchi, P. Klagyivik, N. Kusakabe, R. Luque, M. Mori, T. Nishiumi, J. Prieto-Arranz, M. Tamura, N. Watanabe, T. Gan, K. I. Collins, Eric L.N. Jensen, T. Barclay, J. P. Doty, J. M. Jenkins, D. W. Latham, M. Paegert, G. Ricker, D. R. Rodriguez, S. Seager, A. Shporer, R. Vanderspek, J. Villaseñor, J. N. Winn, B. Wohler, I. Wong

Physics & Astronomy Faculty Works

Context. We report the discovery of TOI-519 b (TIC 218795833), a transiting substellar object (R = 1.07 RJup) orbiting a faint M dwarf (V = 17.35) on a 1.26 d orbit. Brown dwarfs and massive planets orbiting M dwarfs on short-period orbits are rare, but more have already been discovered than expected from planet formation models. TOI-519 is a valuable addition to this group of unlikely systems, and it adds towards our understanding of the boundaries of planet formation. Aims. We set out to determine the nature of the Transiting Exoplanet Survey Satellite (TESS) object of interest TOI-519 b. Methods. …

Vetting Of 384 Tess Objects Of Interest With Triceratops And Statistical Validation Of 12 Planet Candidates, S. Giacalone, C. D. Dressing, Eric L.N. Jensen, K. A. Collins, G. R. Ricker, R. Vanderspek, S. Seager, J. N. Winn, J. M. Jenkins, T. Barclay, K. Barkaoui, C. Cadieux, D. Charbonneau, K. I. Collins, D. M. Conti, R. Doyon, P. Evans, M. Ghachoui, M. Gillon, N. M. Guerrero, R. Hart, E. Jehin, J. F. Kielkopf, B. Mclean, F. Murgas, E. Palle, H. Parviainen, F. J. Pozuelos, H. M. Relles, A. Shporer, Q. Socia, C. Stockdale, T.-G. Tan, G. Torres, J. D. Twicken, W. C. Waalkes, I. A. Waite

Physics & Astronomy Faculty Works

We present TRICERATOPS, a new Bayesian tool that can be used to vet and validate TESS Objects of Interest (TOIs). We test the tool on 68 TOIs that have been previously confirmed as planets or rejected as astrophysical false positives. By looking in the false-positive probability (FPP)−nearby false-positive probability (NFPP) plane, we define criteria that TOIs must meet to be classified as validated planets (FPP < 0.015 and NFPP < 10−3), likely planets (FPP < 0.5 and NFPP < 10−3), and likely nearby false positives (NFPP > 10−1). We apply this procedure on 384 unclassified TOIs and statistically validate 12, classify 125 as likely planets, and classify 52 as likely nearby false positives. Of the 12 statistically validated planets, 9 are newly …

A Planetary System With Two Transiting Mini-Neptunes Near The Radius Valley Transition Around The Bright M Dwarf Toi-776, R. Luque, L. M. Serrano, K. Molaverdikhani, M. C. Nixon, J. H. Livingston, E. W. Guenther, E. Pallé, N. Madhusudhan, G. Nowak, J. Korth, W. D. Cochran, T. Hirano, P. Chaturvedi, E. Goffo, S. Albrecht, O. Barragán, C. Briceño, J. Cabrera, D. Charbonneau, R. Cloutier, K. A. Collins, K. I. Collins, K. D. Colón, J. M. Crossfield, S. Csizmadia, F. Dai, H. J. Deeg, M. Esposito, M. Fridlund, D. Gandolfi, I. Georgieva, A. Glidden, R. F. Goeke, S. Grziwa, A. P. Hatzes, C. E. Henze, S. B. Howell, J. Irwin, J. M. Jenkins, Eric L.N. Jensen, P. Kábath, R. C. Kidwell Jr., J. F. Kielkopf, E. Knudstrup, K. W. F. Lam, D. W. Latham, J. J. Lissauer, A. W. Mann, E. C. Matthews, I. Mireles, N. Narita, M. Paegert, C. M. Persson, S. Redfield, G. R. Ricker, F. Rodler, J. E. Schlieder, N. J. Scott, S. Seager, J. Šubjak, T. G. Tan, E. B. Ting, R. Vanderspek, V. Van Eylen, J. N. Winn, C. Ziegler

Physics & Astronomy Faculty Works

We report the discovery and characterization of two transiting planets around the bright M1 V star LP 961-53 (TOI-776, J = 8.5 mag, M = 0.54 ± 0.03 M ⊙) detected during Sector 10 observations of the Transiting Exoplanet Survey Satellite (TESS). Combining the TESS photometry with HARPS radial velocities, as well as ground-based follow-up transit observations from the MEarth and LCOGT telescopes, for the inner planet, TOI-776 b, we measured a period of P b = 8.25 d, a radius of R b = 1.85 ± 0.13 R ⊕, and a mass of M b = 4.0 ± 0.9 …

Open Data From The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, Rich Abbott, Thomas D. Abbott, Amit Aich, Guldauren Bissenbayeva, Teviet Creighton, Mario C. Diaz, Malik Rakhmanov, Karla E. Ramirez, Palash K. Roy, Wenhui Wang, Adam Zadrozny

Physics & Astronomy Faculty Publications

Advanced LIGO and Advanced Virgo are monitoring the sky and collecting gravitational-wave strain data with sufficient sensitivity to detect signals routinely. In this paper we describe the data recorded by these instruments during their first and second observing runs. The main data products are gravitational-wave strain time series sampled at 16384 Hz. The datasets that include this strain measurement can be freely accessed through the Gravitational Wave Open Science Center at http://gw-openscience.org, together with data-quality information essential for the analysis of LIGO and Virgo data, documentation, tutorials, and supporting software.

Microbially Induced Sedimentary Structures In Clastic Deposits: Implication For The Prospection For Fossil Life On Mars, Nora Noffke

OES Faculty Publications

Abundant and well-preserved fossil microbenthos occurs in siliciclastic deposits of all Earth ages, from the early Archean to today. Studies in modern settings show how microbenthos responds to sediment dynamics by baffling and trapping, binding, biostabilization, and growth. Results of this microbial-sediment interaction are microbially induced sedimentary structures (MISS). Successful prospection for rich MISS occurrences in the terrestrial lithological record requires unraveling genesis and taphonomy of MISS, both of which are defined only by a narrow range of specific conditions. These conditions have to coincide with high detectability which is a function of outcrop quality, bedding character, and rock type. …

Investigating The Agn-Merger Connection Using Close Galaxy Pairs In The Candels Fields, Sean L. Dougherty

Honors Theses

Galaxy mergers are catastrophic events in that they greatly change the properties of the galaxies involved. Observations of the nearby universe suggest that they may also be able to trigger active galactic nuclei (AGN) even prior to the final coalescence, though there is much controversy surrounding this belief, particularly at high redshifts. In order to address this question, we have assembled a large sample of photometric galaxy pairs within the GDS and EGS fields of the CANDELS survey. We use photometric redshift probability distribution functions and the combined redshift probability function to assign probabilities for each projected pair. We incorporate …

Gemini Planet Imager Spectroscopy Of The Dusty Substellar Companion Hd 206893 B, Kimberly Ward-Duong, J. Patience, K. Follette, R. J.De Rosa, J. Rameau, M. Marley, D. Saumon, E. L. Nielsen, A. Rajan, A. Z. Greenbaum, J. Lee, J. J. Wang, I. Czekala, G. Duch Ne, B. Macintosh, S. Mark Ammons, V. P. Bailey, T. Barman, J. Bulger, C. Chen, J. Chilcote, T. Cotten, R. Doyon, T. M. Esposito, M. P. Fitzgerald, B. L. Gerard, S. J. Goodsell, J. R. Graham, P. Hibon, J. Hom, L. W. Hung, P. Ingraham

Astronomy: Faculty Publications

We present new near-infrared Gemini Planet Imager (GPI) spectroscopy of HD 206893 B, a substellar companion orbiting within the debris disk of its F5V star. The J, H, K1, and K2 spectra from GPI demonstrate the extraordinarily red colors of the object, confirming it as the reddest substellar object observed to date. The significant flux increase throughout the infrared presents a challenging atmosphere to model with existing grids. Best-fit values vary from 1200 to 1800 K for effective temperature and from 3.0 to 5.0 for log(g), depending on which individual wavelength band is fit and which model suite is applied. …

Toward Assembling A Comprehensive Database Of Substellar Accretion Rates, Beck Dacus, Cailin Plunkett, Huichen Wang, Katherine B. Follette, Sarah Betti, Anne Peck, Connor Robinson, Kimberly Ward-Duong

Astronomy: Faculty Publications

The relationship between mass and mass accretion rate in young objects is a powerful tool for interrogating formation and evolution. We analyze a comprehensive database of published accretion diagnostics for ∼400 objects (0.005–2 M⊙), including 64 brown dwarfs. To eliminate systematics between studies as the source of the four orders of magnitude of observed scatter, we uniformly re-estimate masses and accretion rates from direct observables (e.g., spectral types, line luminosities). In particular, we adopt a single grid of evolutionary models to estimate masses, a single family of scaling relations to estimate accretion luminosity, and update line luminosities using Gaia DR2 …

Building Mass Functions And Estimating Merger Rates For Calculations Of Cosmic Confusion Noise, Lena Janssen

Undergraduate Research Journal

Compact objects such as white dwarfs, neutron stars, and low mass black holes captured by supermassive black holes, which sit at the center of galaxies with masses over 106 solar masses or greater, generate a background noise in gravitational waves that affects the Laser Interferometer Space Antenna (LISA) and Laser Interferometer Gravitational-Wave Observatory (LIGO) observations. We discuss a way to describe the capture rates by supermassive black holes in an attempt to describe the gravitational waves that will be detected as this background noise in the universe. In order to do this, we calculate the number of black holes in …

Exploring Mesoscale Structures Using Chord Occultations Of Saturn's Rings, Lamia Benyamine

Honors Undergraduate Theses

The Cassini spacecraft orbited Saturn for over 13 years and collected stellar occultations using an Ultraviolet Imaging Spectrograph (UVIS). Chord occultations were analyzed using autocorrelations at minimum ring plane radius to visualize the structure and correlation in the azimuthal direction. These particle tracking occultations cut a chord across the rings in the path of the star. By taking the autocorrelation of these chord occultations, 8 out of the 66 showed clumping within the first 3.0 km in azimuth, representing signs of a structure. Six of those occultations could be moonlets or propellers as their minimum ring plane radii are in …

Simulating Systematic Errors In Exoplanetary Transits For The James Webb Space Telescope, David C. Wright Iii

Honors Undergraduate Theses

The James Webb Space Telescope (JWST) is a next-generation space telescope that will be capable of making transformative observations of planetary transits. As its launch date grows ever closer, it becomes imperative that astronomers have access to accurate simulations of JWST observations in order to best plan observations and devise data analysis pipelines. Unfortunately, available simulation tools do not provide the most accurate or realistic simulations, including noise and systematic errors. In this thesis, I present an open-source time-domain simulator of planetary transits that is capable of accurately modeling these effects in observations made by JWST.

Proton Aurora At Mars: Assessing The Characteristics, Variability, And Driving Mechanisms Of A Newly Discovered Phenomenon, Andréa C.G. Hughes

Doctoral Dissertations and Master's Theses

The purpose of this doctoral research dissertation is to develop a deeper understanding of the phenomenology, variability and driving processes of proton aurora at Mars. Proton aurora are the most recently discovered of the three types of Martian aurora. Due to Mars’ lack of a global dipole magnetic field, the formation processes of Martian proton aurora are uniquely different than aurora on Earth. Martian proton aurora are expected to form on the planet’s dayside via electron stripping/charge exchange processes between solar wind protons and the neutral hydrogen corona. Herein, I present the results of a study of proton aurora at …

Exclusion Statistics For Particles With A Discrete Spectrum, Stéphane Ouvry, Alexios P. Polychronakos

Publications and Research

We formulate and study the microscopic statistical mechanics of systems of particles with exclusion statistics in a discrete one-body spectrum. The statistical mechanics of these systems can be expressed in terms of effective single-level grand partition functions obeying a generalization of the standard thermodynamic exclusion statistics equation of state. We derive explicit expressions for the thermodynamic potential in terms of microscopic cluster coefficients and show that the mean occupation numbers of levels satisfy a nesting relation involving a number of adjacent levels determined by the exclusion parameter. We apply the formalism to the harmonic Calogero model and point out a …

Searching Harder, Localizing Better, Classifying Faster: Optimizing Fast Radio Burst Detection And Analysis, Kshitij Aggarwal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fast Radio Bursts (or FRBs) are millisecond-duration transients of extragalactic origin. They exhibit dispersion caused by propagation through an ionized medium, and quantified by Dispersion Measure (DM). Around 800 FRBs (24 repeaters) have been discovered; so far, 24 FRBs have been confidently associated with a host galaxy. In this thesis, we discuss multiple new FRB search and analysis techniques and the corresponding tools that enable us to search for FRBs harder, localize them better, and classify candidates faster.

We discuss five open-source software suites that can be used in FRB analysis. These suites are used to distinguish between FRBs and …

Near-Infrared And Visible Opacities Of S-Type Stars: The B¹Π—X¹Σ⁺ Band System Of Zro, Jason J. Sorensen, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

The ZrO B¹Π—X¹Σ⁺ transition is an important opacity source in the near-infrared and optical spectrum of S-type stars. The 0–0, 0–1, 0–2, 1–0, 1–2, 1–3, 2–0, 2–1, 2–3, 2–4, 3–1, 3–4, and 4–2 bands of the ⁹⁰Zr¹⁶O B¹Π—X¹Σ⁺ transition are reanalyzed using a high-temperature (2390 K) high-resolution (0.04 cm−1) emission spectrum collected at the National Solar Observatory (Kitt Peak). A modern spectroscopic analysis was performed using the PGOPHER program to provide updated spectroscopic constants and to produce a high-precision line list with line strengths based on an …

Open Data From The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, R. Abbott, T. D. Abbott, S. Abraham, Fausto Acernese, Teviet Creighton, Mario C. Diaz, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, Palash K. Roy, Wenhui Wang, Adam Zadrozny

Physics & Astronomy Faculty Publications

Advanced LIGO and Advanced Virgo are monitoring the sky and collecting gravitational-wave strain data with sufficient sensitivity to detect signals routinely. In this paper we describe the data recorded by these instruments during their first and second observing runs. The main data products are gravitational-wave strain time series sampled at 16384 Hz. The datasets that include this strain measurement can be freely accessed through the Gravitational Wave Open Science Center at http://gw-openscience.org, together with data-quality information essential for the analysis of LIGO and Virgo data, documentation, tutorials, and supporting software.

Line-Of-Sight Winds And Doppler Effect Smearing In Ace-Fts Solar Occultation Measurements, Chris D. Boone, Johnathen Steffen, Jeff Crouse, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Line-of-sight wind profiles are derived from Doppler shifts in infrared solar occultation measurements from the Atmospheric Chemistry Experiment Fourier transform spectrometers (ACE-FTS), the primary instrument on SCISAT, a satellite-based mission for monitoring the Earth’s atmosphere. Comparisons suggest a possible eastward bias from 20 m/s to 30 m/s in ACE-FTS results above 80 km relative to some datasets but no persistent bias relative to other datasets. For instruments operating in a limb geometry, looking through a wide range of altitudes, smearing of the Doppler effect along the line of sight can impact the measured signal, particularly for saturated absorption lines. Implications …

Monitoring Agns With H-Beta Asymmetry: Markarian 841, Samuel J. Schonsberg

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Quasars are among the most luminous objects in the Universe, and the mechanism behind their luminosity was shrouded in mystery decades after their discovery. Since then, we have found that these objects are active galactic nuclei (AGN), which are powered by actively-feeding super massive black holes at the center of a galaxy. But we still know fairly little about the structure and motion of the material surrounding active super massive black holes, and most of these objects are not resolvable by conventional observations. We use a technique called reverberation mapping, which is traditionally used only as a mass determination …

Hunting For Isolated Warm Gas Clouds In The Virgo Cluster Of Galaxies, Nichelle Grabowski

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Studying The Properties Of Massive Elliptical Galaxy Ngc 5044, Huan Le

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

The Nanograv 12.5 Yr Data Set: Wideband Timing Of 47 Millisecond Pulsars, Md F. Alam, Zaven Arzoumanian, Paul T. Baker, Harsha Blumer, Keith E. Bohler, Keeisi Caballero, Richard S. Camuccio, Yhamil Garcia, Jing Luo

Physics & Astronomy Faculty Publications

We present a new analysis of the profile data from the 47 millisecond pulsars comprising the 12.5 yr data set of the North American Nanohertz Observatory for Gravitational Waves, which is presented in a parallel paper (Alam et al., hereafter NG12.5). Our reprocessing is performed using “wideband” timing methods, which use frequency-dependent template profiles, simultaneous time-of-arrival (TOA) and dispersion measure (DM) measurements from broadband observations, and novel analysis techniques. In particular, the wideband DM measurements are used to constrain the DM portion of the timing model. We compare the ensemble timing results to those in NG12.5 by examining the …

Agn Jets And A Fanciful Trio Of Black Holes In The Abell 85 Brightest Cluster Galaxy, Juan P. Madrid

Physics & Astronomy Faculty Publications

A new radio map of the Abell 85 Brightest Cluster Galaxy (BCG) was obtained with the Karl G. Jansky Very Large Array. With a resolution of 002, this radio image shows two kiloparsec-scale bipolar active galactic nucleus jets emanating from the active galactic nucleus of the A85 BCG. The galaxy core appears as a single entity on the new radio map. It has been assumed that the A85 BCG contained a binary black hole in its core. However, Chandra X-ray data and the new high-resolution radio map show no evidence that the A85 BCG harbors a binary black hole. The …

Ligo Detector Characterization In The Second And Third Observing Runs, D. Davis, J. S. Areeda, B. K. Berger, R. Bruntz, A. Effler, R. C. Essick, R. P. Fisher, B. Martinez, Karla E. Ramirez, P. Godwin

Physics & Astronomy Faculty Publications

The characterization of the Advanced LIGO detectors in the second and third observing runs has increased the sensitivity of the instruments, allowing for a higher number of detectable gravitational-wave signals, and provided confirmation of all observed gravitational-wave events. In this work, we present the methods used to characterize the LIGO detectors and curate the publicly available datasets, including the LIGO strain data and data quality products. We describe the essential role of these datasets in LIGO–Virgo Collaboration analyses of gravitational-waves from both transient and persistent sources and include details on the provenance of these datasets in order to support analyses …

A Detailed X-Ray Analysis Of The Cold Front In Relics Cluster A2163, Anne Poy

CMC Senior Theses

Galaxy clusters are the largest gravitationally bound objects in the Universe. Studying them can teach us about how they merge and grow, which in turn provides unparalleled information about the history of the evolution of the Universe. X-ray observations of galaxy clusters have uncovered substructure in the hot, X-ray emitting gas known as the intracluster mediums (ICM). Substructure indicates that the ICM has been churned up, possibly by a significant off-axis merger event. This substructure includes cold fronts, sloshing spirals, and shocks. We present deep Chandra observations of the merging cluster Abell 2163. We investigate the global spectrum and find …

Simulating Ejecta Blown Off The Lunar Surface Due To Landing Spacecraft Using The Mercury N-Body Integrator, Isabel Rivera

Electronic Theses and Dissertations, 2020-2023

The experiences of the Apollo lunar landings revealed the danger lunar dust can pose to surrounding hardware, outposts, and orbiting spacecraft. Future lunar missions such as the Artemis program will require more information about the trajectories of ejecta blown by landers to protect orbiting spacecraft such as the Lunar Gateway. In this paper, we simulate lunar lander ejecta trajectories using the Mercury N-body integrator. We placed cones of test particles on the Moon at the North Pole, South Pole, and Equator with various ejection speeds and angles. The results show that particles ejected at speeds near the Moon's escape velocity …

Development Of Eccentric Black Hole Binary Searches In The Ligo And Pta Regimes, Belinda D. Cheeseboro

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the past several years, a plethora of gravitational wave events have been detected leading to better understanding of binary black holes, binary neutron stars, and neutron star black hole binaries. All of these transient detections have helped us better understand the dynamics of these systems as well as the populations of these objects, but each of these sources was detected with models that neglected eccentricity. Eccentricity is one of several potential markers for determining the formation of binary systems. Detecting gravitational waves from eccentric sources can better our understanding of such systems and help constrain theories about their formation. …

Pulsar Noise Processes And Emission Physics, Brent Jacob Shapiro-Albert

Graduate Theses, Dissertations, and Problem Reports (ETD)

Precision pulsar timing can be used to study many different astrophysically interesting phenomena, from the emission mechanism of pulsars to the detection of nanohertz gravitational waves. These analyses span topics such as studying the single pulses of pulsars and analyzing years of pulsar timing data from pulsar timing arrays (PTAs). Single-pulse studies allow us to glean information on the emission physics of pulsars on their shortest timescales, while PTA observations of millisecond pulsars (MSPs) allow us to not only study the pulsars themselves, but also probe the interstellar medium (ISM) and constrain the noise in the data for precision pulsar …