Astrophysics and Astronomy Commons^™

The Pedagogical Representation Of Mass Functions With Lego And Their Origin, Stefan Kautsch

Chemistry and Physics Faculty Articles

We promote the teaching of mass functions as an integral part of an interdisciplinary science education. Mass functions characterize the frequency distributions of objects with different masses on all cosmic scales. We intend to enhance experiential learning of this concept with a creative LEGO brick experiment for a diverse student audience. To our surprise, the LEGO mass function is not only qualitatively but also quantitatively comparable to mass functions found across the universe. We also discuss the relation between gravitation and mass distributions as a possible explanation for the continuity of the universal mass function.

A Cautionary Tale In Fitting Galaxy Rotation Curves With Bayesian Techniques: Does Newton's Constant Vary From Galaxy To Galaxy?, Pengfei Li, Stacy Mcgaugh

Faculty Scholarship

The application of Bayesian techniques to astronomical data is generally non-trivial because the fitting parameters can be strongly degenerated and the formal uncertainties are themselves uncertain. An example is provided by the contradictory claims over the presence or absence of a universal acceleration scale (g†) in galaxies based on Bayesian fits to rotation curves. To illustrate this we present an analysis in which the Newtonian gravitational constant GN is allowed to vary from galaxy to galaxy when fitting rotation curves from the SPARC database, in analogy to g† in the recently debated Bayesian analyses. When imposing flat priors on GN, …

Speckle Imaging Characterization Of Radial Velocity Exoplanet Systems, Paul A. Dalba, Stephen R. Kane, Steve B. Howell, Elliott P. Horch, Zhexing Li, Lea A. Hirsch, Jennifer Burt, Timothy D. Brandt, Teo Močnik, Gregory W. Henry, Mark E. Everett, Lee J. Rosenthal, Andrew W. Howard

Information Systems and Engineering Management Research Publications

We conducted speckle imaging observations of 53 stellar systems that were members of long-term radial velocity (RV) monitoring campaigns and exhibited substantial accelerations indicative of planetary or stellar companions in wide orbits. Our observations were made with blue and red filters using the Differential Speckle Survey Instrument at Gemini-South and the NN-Explore Exoplanet Stellar Speckle Imager at the WIYN telescope. The speckle imaging identifies eight luminous companions within 2'' of the primary stars. In three of these systems—HD 1388, HD 87359, and HD 104304—the properties of the imaged companion are consistent with the RV measurements, suggesting that these companions may …

Constraining Protoplanetary Disc Accretion And Young Planets Using Alma Kinematic Observations, Ian Rabago, Zhaohuan Zhu

Physics & Astronomy Faculty Research

Recent ALMA molecular line observations have revealed 3D gas velocity structure in protoplanetary discs, shedding light on mechanisms of disc accretion and structure formation. (1) By carrying out viscous simulations, we confirm that the disc's velocity structure differs dramatically using vertical stress profiles from different accretion mechanisms. Thus, kinematic observations tracing flows at different disc heights can potentially distinguish different accretion mechanisms. On the other hand, the disc surface density evolution is mostly determined by the vertically integrated stress. The sharp disc outer edge constrained by recent kinematic observations can be caused by a radially varying alpha in the disc. …

Turbulent Gas In Lensed Planck-Selected Starbursts At Z ∼ 1-3.5, Kevin C. Harrington, Axel Weiss, Min S. Yun, Benjamin Magnelli, C. E. Sharon, T. K.D. Leung, A. Vishwas, Q. D. Wang, D. T. Frayer, E. F. Jiménez-Andrade, D. Liu, P. García, E. Romano-Díaz, B. L. Frye, S. Jarugula, T. Bǎdescu, D. Berman, H. Dannerbauer, A. Díaz-Sánchez, L. Grassitelli, P. Kamieneski, W. J. Kim, A. Kirkpatrick, J. D. Lowenthal, H. Messias, J. Puschnig, G. J. Stacey, P. Torne, F. Bertoldi

Astronomy: Faculty Publications

Dusty star-forming galaxies at high redshift (1 < z < 3) represent the most intense star-forming regions in the universe. Key aspects to these processes are the gas heating and cooling mechanisms, and although it is well known that these galaxies are gas-rich, little is known about the gas excitation conditions. Only a few detailed radiative transfer studies have been carried out owing to a lack of multiple line detections per galaxy. Here we examine these processes in a sample of 24 strongly lensed star-forming galaxies identified by the Planck satellite (LPs) at z ∼ 1.1-3.5. We analyze 162 CO rotational transitions (ranging from J up = 1 to 12) and 37 atomic carbon fine-structure lines ([C i]) in order to characterize the physical conditions of the gas in the sample of LPs. We simultaneously fit the CO and [C i] lines and the dust continuum emission, using two different non-LTE, radiative transfer models. The first model represents a two-component gas density, while the second assumes a turbulence-driven lognormal gas density distribution. These LPs are among the most gas-rich, IR-luminous galaxies ever observed (μL L IR(8-1000 μm) ∼ 1013-14.6 L⊙; «μLMISM» = (2.7 ± 1.2) × 1012 Mo˙ with μL ∼ 10-30 the average lens magnification factor). Our results suggest that the turbulent interstellar medium present in the LPs can be well characterized by a high turbulent velocity dispersion («ΔVturb» ∼ 100 km s-1) and ratios of gas kinetic temperature to dust temperature «T kin/T d» ∼ 2.5, sustained on scales larger than a few kiloparsecs. We speculate that the average surface density of the molecular gas mass and IR luminosity, Σ ∼ 103-4 M o˙ pc-2 and Σ ∼ 1011-12 L o˙ kpc-2, arise from both stellar mechanical feedback and a steady momentum injection from the accretion of intergalactic gas.

Measurement Of Time-Dependent Cp Violation Parameters In B0 → Ks0 Ks0 Ks0 Decays At Belle, K. H. Kang, H. Park, T. Higuchi, K. Miyabayashi, K. Sumisawa, I. Adachi, J. K. Ahn, H. Aihara, S. Al Said, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, A. M. Bakich, P. Behera, C. Beleño, J. Bennett

Faculty and Student Publications

We measure the time-dependent CP violation parameters in B0→KS0KS0KS0 decays using 772×106BB¯ pairs collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. The obtained mixing-induced and direct CP asymmetries are -0.71±0.23 (stat)±0.05 (syst) and 0.12±0.16 (stat)±0.05 (syst), respectively. These values are consistent with the Standard Model predictions. The significance of CP violation differs from zero by 2.5 standard deviations.

Non-Diffracting States At Exceptional Points, Cem Yuce, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

We propose to use exceptional points (EPs) to construct diffraction-free beam propagation and localized power oscillation in lattices. We specifically consider two systems to utilize EPs for diffraction-free beam propagation, one in synthetic gauge lattices and the other one, in unidirectionally coupled resonators where each resonator individually is capable of creating orbital angular momentum beams (OAM). In the second system, we introduce the concept of robust and tunable OAM beam propagation in discrete lattices. We show that one can create robust OAM beams in an arbitrary number of sites of a photonic lattice. Furthermore, we report power oscillation at the …

Extending The Frequency Reach Of Pulsar Timing Array Based Gravitational Wave Search Without High Cadence Observations, Yan Wang, Soumya Mohanty, Zhoujian Cao

Physics & Astronomy Faculty Publications

Gravitational wave (GW) searches using pulsar timing arrays (PTAs) are assumed to be limited by the typical average observational cadence of 1/(2 weeks) for a single pulsar to GW frequencies . 4 × 10−7 Hz. We show that this assumption is incorrect and that a PTA can detect signals with much higher frequencies, which are preserved in the data due to aliasing, by exploiting asynchronous observations from multiple pulsars. This allows an observation strategy that is scalable to future large-scale PTAs containing O(103) pulsars, enabled by the Five-hundred meter Aperture Spherical Telescope and the Square Kilometer Array, without requiring a …

Scalable, Cost-Efficient Synthesis And Properties Optimization Of Magnetoelectric Cobalt Ferrite/Barium Titanate Composites, Farnaz Safi Samghabadi, Long Chang, Mohammad Khodadadi, Karen S. Martirosyan, Dmitri Litvinov

Physics & Astronomy Faculty Publications

Cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) particulate composites exhibiting high magnetoelectric coefficients were synthesized from low-cost commercial precursors using mechanical ball milling followed by high-temperature annealing. CoFe2O4 (20 nm–50 nm) and either cubic or tetragonal BaTiO3 nanoparticle powders were used for the synthesis. It was found that utilizing a 50nm cubic BaTiO3 powder as a precursor results in a composite with a magnetoelectric coupling coefficient value as high as 4.3 mV/Oe cm, which is comparable to those of chemically synthesized core–shell CoFe2O4–BaTiO3 nanoparticles. The microstructure of these composites is dramatically different from the composite synthesized using 200nm tetragonal BaTiO3 powder. CoFe2O4 …

Scalable, Cost-Efficient Synthesis And Properties Optimization Of Magnetoelectric Cobalt Ferrite/Barium Titanate Composites, Farnaz Safi Samghabadi, Long Chang, Mohammad Khodadadi, Karen S. Martirosyan, Dmitri Litvinov

Physics & Astronomy Faculty Publications

Cobalt ferrite (CoFe2O4)/barium titanate (BaTiO3) particulate composites exhibiting high magnetoelectric coefficients were synthesized from low-cost commercial precursors using mechanical ball milling followed by high-temperature annealing. CoFe2O4 (20 nm–50 nm) and either cubic or tetragonal BaTiO3 nanoparticle powders were used for the synthesis. It was found that utilizing a 50nm cubic BaTiO3 powder as a precursor results in a composite with a magnetoelectric coupling coefficient value as high as 4.3 mV/Oe cm, which is comparable to those of chemically synthesized core–shell CoFe2O4–BaTiO3 nanoparticles. The microstructure of these composites is dramatically different from the composite synthesized using 200nm tetragonal BaTiO3 powder. CoFe2O4 …

Observations Of Particle Loss Due To Injection-Associated Electromagnetic Ion Cyclotron Waves, Hyomin Kim, Quintin Schiller, Mark J. Engebretson, Sungjun Noh, Ilya Kuzichev, Louis J. Lanzerotti, Andrew J. Gerrard, Khan Hyuk Kim, Marc R. Lessard, Harlan E. Spence, Dae Young Lee, Jürgen Matzka, Tanja Fromm

Faculty Authored Articles

We report on observations of electromagnetic ion cyclotron (EMIC) waves and their interactions with injected ring current particles and high energy radiation belt electrons. The magnetic field experiment aboard the twin Van Allen Probes spacecraft measured EMIC waves near L = 5.5–6. Particle data from the spacecraft show that the waves were associated with particle injections. The wave activity was also observed by a ground-based magnetometer near the spacecraft geomagnetic footprint over a more extensive temporal range. Phase space density profiles, calculated from directional differential electron flux data from Van Allen Probes, show that there was a significant energy-dependent relativistic …

Anomalous Dimensions From Gauge Couplings In Smeft With Right-Handed Neutrinos, Alakabha Datta, Jacky Kumar, Hongkai Liu, Danny Marfatia

Faculty and Student Publications

Standard Model Neutrino Effective Field Theory (SMNEFT) is an effective theory with Standard Model (SM) gauge-invariant operators constructed only from SM and right-handed neutrino fields. For the full set of dimension-six SMNEFT operators, we present the gauge coupling terms of the one-loop anomalous dimension matrix for renormalization group evolution (RGE) of the Wilson coefficients between a new physics scale and the electroweak scale. We find that the SMNEFT operators can be divided into five subsets which are closed under RGE. Our results apply for both Dirac and Majorana neutrinos. We also discuss the operator mixing pattern numerically and comment on …

Observing The Changing Surface Structures Of The Active K Giant Σ Geminorum With Song★, Heidi Korhonen, Rachael M. Roettenbacher, Shenghong Gu, Frank Grundahl, Mads Fredslund Andersen, Gregory W. Henry, Jens Jessen-Hansen, Victoria L. Antoci, P. L. Pallé

Information Systems and Engineering Management Research Publications

Aims. We aim to study the spot evolution and differential rotation in the magnetically active cool K-type giant star σ Gem from broadband photometry and continuous spectroscopic observations that span 150 nights.

Methods. We use high-resolution, high signal-to-noise ratio spectra obtained with the Hertzsprung SONG telescope to reconstruct surface (photospheric) temperature maps with Doppler imaging techniques. The 303 observations span 150 nights and allow for a detailed analysis of the spot evolution and surface differential rotation. The Doppler imaging results are compared to simultaneous broadband photometry from the Tennessee State University T3 0.4 m Automated Photometric Telescope. The activity from …

Toi-954 B And K2-329 B: Short-Period Saturn-Mass Planets That Test Whether Irradiation Leads To Inflation, L. Sha, C. X. Huang, A. Shporer, J. E. Rodriguez, A. Vanderburg, R. Brahm, J. Hagelberg, E. C. Matthews, C. Ziegler, J. H. Livingston, K. G. Stassun, D. J. Wright, J. D. Crane, N. Espinoza, F. Bouchy, G. Á. Bakos, K. A. Collins, G. Zhou, A. Bieryla, J. D. Hartman, R. A. Wittenmyer, L. D. Nielsen, P. Plavchan, D. Bayliss, P. Sarkis, T.-G. Tan, R. Cloutier, L. Mancini, A. Jordán, S. Wang, T. Henning, N. Narita, K. Penev, J. K. Teske, S. R. Kane, A. W. Mann, B. C. Addison, M. Tamura, J. Horner, M. Barbieri, J. A. Burt, M. R. Díaz, I. J. M. Crossfield, D. Dragomir, H. Drass, A. D. Feinstein, H. Zhang, R. Hart, J. F. Kielkopf, Eric L.N. Jensen, B. T. Montet, G. Ottoni, R. P. Schwarz, F. Rojas, D. Nespral, P. Torres, M. W. Mengel, S. Udry, A. Zapata, E. Snoddy, J. Okumura, G. R. Ricker, R. K. Vanderspek, D. W. Latham, J. N. Winn, S. Seager, J. M. Jenkins, K. D. Colón, C. E. Henze, A. Krishnamurthy, E. B. Ting, M. Vezie, S. Villanueva

Physics & Astronomy Faculty Works

We report the discovery of two short-period Saturn-mass planets, one transiting the G subgiant TOI-954 (TIC 44792534, V = 10.343, T = 9.78) observed in TESS sectors 4 and 5 and one transiting the G dwarf K2-329 (EPIC 246193072, V = 12.70, K = 10.67) observed in K2 campaigns 12 and 19. We confirm and characterize these two planets with a variety of ground-based archival and follow-up observations, including photometry, reconnaissance spectroscopy, precise radial velocity, and high-resolution imaging. Combining all available data, we find that TOI-954 b has a radius of ${0.852}_{-0.062}^{+0.053}\,{R}_{{\rm{J}}}$and a mass of ${0.174}_{-0.017}^{+0.018}$MJ and is in a …

The Tess-Keck Survey. Ii. An Ultra-Short-Period Rocky Planet And Its Siblings Transiting The Galactic Thick-Disk Star Toi-561, L. M. Weiss, F. Dai, D. Huber, J. M. Brewer, K. A. Collins, D. R. Ciardi, E. C. Matthews, C. Ziegler, S. B. Howell, N. M. Batalha, I. J. M. Crossfield, C. Dressing, B. Fulton, A. W. Howard, H. Isaacson, S. R. Kane, E. A. Petigura, P. Robertson, A. Roy, R. A. Rubenzahl, J. D. Twicken, Z. R. Claytor, K. G. Stassun, M. G. Macdougall, A. Chontos, S. Giacalone, P. A. Dalba, T. Mocnik, M. L. Hill, C. Beard, J. M. Akana Murphy, L. J. Rosenthal, A. Behmard, J. Van Zandt, J. Lubin, M. R. Kosiarek, M. B. Lund, J. L. Christiansen, R. A. Matson, C. A. Beichman, J. E. Schlieder, E. J. Gonzales, C. Briceño, N. Law, A. W. Mann, K. I. Collins, P. Evans, A. Fukui, Eric L.N. Jensen, F. Murgas, N. Narita, E. Palle, H. Parviainen, R. P. Schwarz, T.-G. Tan, J. S. Acton, P. Eigmüller, J. Jenkins, G. Ricker, S. Seager, J. N. Winn

Physics & Astronomy Faculty Works

We report the discovery of TOI-561, a multiplanet system in the galactic thick disk that contains a rocky, ultra-short-period planet. This bright (V = 10.2) star hosts three small transiting planets identified in photometry from the NASA TESS mission: TOI-561 b (TOI-561.02, P = 0.44 days, Rp = 1.45 ± 0.11 R⊕), c (TOI-561.01, P = 10.8 days, Rp = 2.90 ± 0.13 R⊕), and d (TOI-561.03, P = 16.3 days, Rp = 2.32 ± 0.16 R⊕). The star is chemically ([Fe/H] = −0.41 ± 0.05, [α/Fe] = +0.23 ± 0.05) and kinematically consistent with the galactic thick-disk population, making …

Tess Discovery Of A Super-Earth And Three Sub-Neptunes Hosted By The Bright, Sun-Like Star Hd 108236, T. Daylan, K. Pinglé, J. Wright, M. N. Günther, K. G. Stassun, S. R. Kane, A. Vanderburg, D. Jontof-Hutter, J. E. Rodriguez, A. Shporer, C. X. Huang, T. Mikal-Evans, M. Badenas-Agusti, K. A. Collins, B. V. Rackham, S. N. Quinn, R. Cloutier, K. I. Collins, P. Guerra, Eric L.N. Jensen, J. F. Kielkopf, B. Massey, R. P. Schwarz, D. Charbonneau, J. J. Lissauer, J. M. Irwin, Ö Baştürk, B. Fulton, A. Soubkiou, B. Zouhair, S. B. Howell, C. Ziegler, C. Briceño, N. Law, A. W. Mann, N. Scott, E. Furlan, D. R. Ciardi, R. Matson, C. Hellier, D. R. Anderson, R. P. Butler, J. D. Crane, J. K. Teske, S. A. Shectman, M. H. Kristiansen, I. A. Terentev, H. M. Schwengeler, G. R. Ricker, R. Vanderspek, S. Seager, J. N. Winn, J. M. Jenkins, Z. K. Berta-Thompson, L. G. Bouma, W. Fong, G. Furesz, C. E. Henze, E. H. Morgan, E. Quintana, E. B. Ting, J. D. Twicken

Physics & Astronomy Faculty Works

We report the discovery and validation of four extrasolar planets hosted by the nearby, bright, Sun-like (G3V) star HD 108236 using data from the Transiting Exoplanet Survey Satellite (TESS). We present transit photometry, reconnaissance, and precise Doppler spectroscopy, as well as high-resolution imaging, to validate the planetary nature of the objects transiting HD 108236, also known as the TESS Object of Interest (TOI) 1233. The innermost planet is a possibly rocky super-Earth with a period of ${3.79523}_{-0.00044}^{+0.00047}$days and has a radius of 1.586 ± 0.098 R⊕. The outer planets are sub-Neptunes, with potential gaseous envelopes, having radii of ${2.068}_{-0.091}^{+0.10}$R⊕, 2.72 …

Tess Hunt For Young And Maturing Exoplanets (Thyme). Iv. Three Small Planets Orbiting A 120 Myr Old Star In The Pisces–Eridanus Stream, E. R. Newton, A. W. Mann, A. L. Kraus, J. H. Livingston, A. Vanderburg, J. L. Curtis, P. C. Thao, K. Hawkins, M. L. Wood, A. C. Rizzuto, A. Soubkiou, B. M. Tofflemire, G. Zhou, I. J. M. Crossfield, L. A. Pearce, K. A. Collins, D. M. Conti, T.-G. Tan, S. Villanueva, A. Spencer, D. Dragomir, S. M. Quinn, Eric L.N. Jensen, K. I. Collins, C. Stockdale, R. Cloutier, C. Hellier, Z. Benkhaldoun, C. Ziegler, C. Briceño, N. Law, B. Benneke, J. L. Christiansen, V. Gorjian, S. R. Kane, L. Kreidberg, F. Y. Morales, M. W. Werner, J. D. Twicken, A. M. Levine, D. R. Ciardi, N. M. Guerrero, K. Hesse, E. V. Quintana, B. Shiao, J. C. Smith, G. Torres, G. R. Ricker, R. Vanderspek, S. Seager, J. N. Winn, J. M. Jenkins, D. W. Latham

Physics & Astronomy Faculty Works

Young exoplanets can offer insight into the evolution of planetary atmospheres, compositions, and architectures. We present the discovery of the young planetary system TOI 451 (TIC 257605131, Gaia DR2 4844691297067063424). TOI 451 is a member of the 120 Myr old Pisces–Eridanus stream (Psc–Eri). We confirm membership in the stream with its kinematics, its lithium abundance, and the rotation and UV excesses of both TOI 451 and its wide-binary companion, TOI 451 B (itself likely an M-dwarf binary). We identified three candidate planets transiting in the Transiting Exoplanet Survey Satellite data and followed up the signals with photometry from Spitzer and …

Identification Of A Local Sample Of Gamma-Ray Bursts Consistent With A Magnetar Giant Flare Origin, E. Burns, D. Svinkin, K Hurley, Z. Wadiasingh, M. Negro, G. Younes, R. Hamburg, A. Ridnaia, D. Cook, S. B. Cenko, R. Aloisi, G. Ashton, M. Baring, M. S. Briggs, N. Christensen, D. Frederiks, A. Goldstein, C. M. Hui, D. L. Kaplan, M. M. Kasliwal, D. Kocevski, O. J. Roberts, V. Savchenko, A. Tohuvavohu, P. Veres, C. A. Wilson-Hodge

Faculty Publications

Cosmological gamma-ray bursts (GRBs) are known to arise from distinct progenitor channels: short GRBs mostly from neutron star mergers and long GRBs from a rare type of core-collapse supernova (CCSN) called collapsars. Highly magnetized neutron stars called magnetars also generate energetic, short-duration gamma-ray transients called magnetar giant flares (MGFs). Three have been observed from the Milky Way and its satellite galaxies, and they have long been suspected to constitute a third class of extragalactic GRBs. We report the unambiguous identification of a distinct population of four local (<5 Mpc) short GRBs, adding GRB 070222 to previously discussed events. While identified solely based on alignment with nearby star-forming galaxies, their rise time and isotropic energy release are independently inconsistent with the larger short GRB population at >99.9% confidence. These properties, the host galaxies, and nondetection in gravitational waves …

Carbon Combustion Synthesis Of Janus-Like Particles Of Magnetoelectric Cobalt Ferrite And Barium Titanate, Carlos Trevino De Leo, Gamage Chamath Dannangoda, Mkhitar A. Hobosyan, J. T. Held, F. Safi Samghabadi, Mohammad Khodadadi, Dmitri Litvinov, K. A. Mkhoyan, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

Carbon combustion synthesis of oxides was applied for quick and energy efficient production of multiferroic composite of cobalt ferrite and barium titanate to form Janus-like particles matrix structure. The exothermic oxidation of carbon nanoparticles with an average size of 5 nm and a specific surface area of 110 m2/g generates a self-propagating thermal wave with peak temperature of up to 1000 °C. The thermal front rapidly propagates through the mixture of solid reactants (magnetic- CoFe2O4 and ferroelectric-BaTiO3) and results in localized hot-spot sintering of magneto-electric phases to form a nanocomposite structure. Carbon is not incorporated in the product and is …

Anomalous Stellar Populations In Low-Surface-Brightness Galaxies, Stacy S. Mcgaugh

Faculty Scholarship

We present new Hubble Space Telescope WFC3 near-IR observations of the color-magnitude diagrams (CMDs) in two low-surface-brightness galaxies, F575-3 and F615-1, notable for having no current star formation based on a lack of Ha emission. Key features of the near-IR CMDs are resolved, such as the red giant branch (RGB), the asymptotic giant branch (AGB) region, and the top of the blue main sequence. F575-3 has the bluest RGB of any CMD in the literature, indicating an extremely low mean metallicity. F615-1 has unusually wide RGB and AGB sequences, suggesting multiple episodes of star formation from metal-poor gas, and possibly …

Kozai–Lidov Oscillations Triggered By A Tilt Instability Of Detached Circumplanetary Discs, Rebecca G. Martin, Zhaohuan Zhu, Philip J. Armitage, Chao-Chin Yang, Hans Baehr

Physics & Astronomy Faculty Research

Circumplanetary discs can be linearly unstable to the growth of disc tilt in the tidal potential of the star–planet system. We use 3D hydrodynamical simulations to characterize the disc conditions needed for instability, together with its long-term evolution. Tilt growth occurs for disc aspect ratios, evaluated near the disc outer edge, of H/r ≳ 0.05, with a weak dependence on viscosity in the wave-like regime of warp propagation. Lower mass giant planets are more likely to have circumplanetary discs that satisfy the conditions for instability. We show that the tilt instability can excite the inclination to above the threshold where …

Beam Spin Asymmetry In Semi-Inclusive Electroproduction Of Hadron Pairs, M. Mirazita, H. Avakian, A. Courtoy, S. Pisano, S. Pisano, S. Adhikari, M. J. Amaryan, Giovanni Angelini, H. Atac, N. A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, Fatiha Benmokhtar, A. Bianconi, A. S. Biselli, F. Bossù, S. Boiarinov, W. J. Briscoe, W. K. Brooks, Steffen Strauch, Et. Al.

Faculty Publications

A first measurement of the longitudinal beam spin asymmetry 𝐴_𝐿⁢𝑈 in the semi-inclusive electroproduction of pairs of charged pions is reported. 𝐴_𝐿⁢𝑈 is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function 𝑒⁡(𝑥). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the 𝐴^{sin⁡𝜙𝑅} _LU moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production …

Galaxy And Mass Assembly: Group And Field Galaxy Morphologies In The Star-Formation Rate - Stellar Mass Plane, W. J. Pearson, L. Wang, S. Brough, Benne Holwerda, A. M. Hopkins, J. Loveday

Faculty and Staff Scholarship

Aims. We study the environment in which a galaxy lies (i.e. field or group) and its connection with the morphology of the galaxy. This is done by examining the distribution of parametric and non-parametric statistics across the star-formation rate (SFR) - stellar mass (M?) plane and studying how these distributions change with the environment in the local universe (z < 0.15). Methods. We determine the concentration (C), Gini, M20, asymmetry, Gini-M20 bulge statistic (GMB), 50% light radius (r50), total Sérsic index, and bulge Sérsic index (nBulge) for galaxies from the Galaxy and Mass Assembly (GAMA) survey using optical images from the Kilo Degree Survey. We determine the galaxy environment using the GAMA group catalogue and split the galaxies into field or group galaxies. The group galaxies are further divided by the group halo mass (Mh) - 11 ≤ log(Mh /M*) < 12, 12 ≤ log(Mh /M*) < 13, and 13 ≤ log(Mh /M*) < 14 - and into central and satellite galaxies. The galaxies in each of these samples are then placed onto the SFR-M? plane, and each parameter is used as a third dimension. We fit the resulting distributions for each parameter in each sample using two two-dimensional Gaussian distributions: one for star-forming galaxies and one for quiescent galaxies. The coefficients of these Gaussian fits are then compared between environments. Results. Using C and r50, we find that galaxies typically become larger as the group mass increases. This change is greater for larger galaxies. There is no indication that galaxies are typically more or less clumpy as the environment changes. Using GMB and nBulge , we see that the star-forming galaxies do not become more bulge or disk dominated as the group mass changes. Asymmetry does not appear to be greatly influenced by environment.

Evidence Of The Four-Quark Nature Of F0 (980) And F0 (500), N. N. Achasov, J. V. Bennett, A. V. Kiselev, E. A. Kozyrev, G. N. Shestakov

Faculty and Student Publications

There exists a great deal of concrete evidence in favor of the exotic four-quark nature of light scalars. At the same time, the further expansion of the area of the q2q¯2 model validity for light scalars on ever new processes seems extremely interesting and important. We analyze the BESIII data on the decay J/ψ→γπ0π0 and show that the results of this high-statistics experiment can be interpreted in favor of the four-quark nature of light scalar mesons f0(980) and f0(500).

Concentrated Lunar Resources: Imminent Implications For Governance And Justice, Martin Elvis, Alanna Krolikowski, Tony Milligan

History and Political Science Faculty Research & Creative Works

Numerous missions planned for the next decade are likely to target a handful of small sites of interest on the Moon's surface, creating risks of crowding and interference at these locations. The Moon presents finite and scarce areas with rare topography or concentrations of resources of special value. Locations of interest to science, notably for astronomy, include the Peaks of Eternal Light, the coldest of the cold traps and smooth areas on the far side. Regions richest in physical resources could also be uniquely suited to settlement and commerce. Such sites of interest are both few and small. Typically, there …

Search For Slow Magnetic Monopoles With The Nova Detector On The Surface, M. A. Acero, P. Adamson, L. Aliaga, T. Alion, V. Allakhverdian, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, C. Backhouse, M. Biard, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, S. Bending, R. Bernstein, Roberto Petti, Sanjib R. Mishra Ph.D., Et. Al.

Faculty Publications

We report a search for a magnetic monopole component of the cosmic-ray flux in a 95-day exposure of the NOvA experiment’s Far Detector, a 14 kt segmented liquid scintillator detector designed primarily to observe GeV-scale electron neutrinos. No events consistent with monopoles were observed, setting an upper limit on the flux of 2 × 10⁻¹⁴ cm⁻² s⁻¹ sr⁻¹ at 90% C.L. for monopole speed 6 × 10⁻⁴ < β < 5 × 10⁻³ and mass greater than 5 × 10⁸ GeV. Because of NOvA’s small overburden of 3 meters-water equivalent, this constraint covers a previously unexplored low-mass region.

The Hubble Pancet Program: A Metal-Rich Atmosphere For The Inflated Hot Jupiter Hat-P-41b, Kyle B. Sheppard, Luis Welbanks, Avi M. Mandell, Nikku Madhusudhan, Nikolay Nikolov, Drake Deming, Gregory W. Henry, Michael H. Williamson, David K. Sing, Mercedes López-Morales, Jegug Ih, Jorge Sanz-Forcada, Panayotis Lavvas, Gilda E. Ballester, Thomas M. Evans, Antonio García Muñoz, Leonardo A. Dos Santos

Information Systems and Engineering Management Research Publications

We present a comprehensive analysis of the 0.3–5 μm transit spectrum for the inflated hot Jupiter HAT-P-41b. The planet was observed in transit with Hubble STIS and WFC3 as part of the Hubble Panchromatic Comparative Exoplanet Treasury (PanCET) program, and we combine those data with warm Spitzer transit observations. We extract transit depths from each of the data sets, presenting the STIS transit spectrum (0.29–0.93 μm) for the first time. We retrieve the transit spectrum both with a free-chemistry retrieval suite (AURA) and a complementary chemical equilibrium retrieval suite (PLATON) to constrain the atmospheric properties at the day–night terminator. Both …

Analysis Of Bending Waves In Saturn's Rings, Claudia Denise Orozco Vega

Honors Undergraduate Theses

Saturn's rings are a complex, dynamic system that can provide unique insight into the structure and features of the planet and surrounding system. We use stellar occultation data of Saturn's rings collected from the Cassini Ultraviolet Imaging Spectrograph to visualize and analyze bending waves present within the rings. Analysis of the propagation of these waves gives insight into the surface mass density of the local ring region and can be used to further our understanding of ring dynamics and ring formation. Our analysis of the Mimas 7:4 bending wave estimated a surface mass density between 30 g cm^-2 and …

Toi 122b And Toi 237b: Two Small Warm Planets Orbiting Inactive M Dwarfs Found By Tess, W. C. Waalkes, Z. K. Berta-Thompson, K. A. Collins, A. D. Feinstein, B. M. Tofflemire, B. Rojas-Ayala, M. L. Silverstein, E. Newton, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, J. Christiansen, R. F. Goeke, A. M. Levine, H. P. Osborn, S. A. Rinehart, M. E. Rose, E. B. Ting, J. D. Twicken, K. Barkaoui, J. L. Bean, C. Briceño, D. R. Ciardi, K. I. Collins, D. Conti, T. Gan, M. Gillon, G. Isopi, E. Jehin, Eric L.N. Jensen, J. F. Kielkopf, N. Law, F. Mallia, A. W. Mann, B. T. Montet, F. J. Pozuelos, H. Relles, J. E. Libby-Roberts, C. Ziegler

Physics & Astronomy Faculty Works

We report the discovery and validation of TOI 122b and TOI 237b, two warm planets transiting inactive M dwarfs observed by the Transiting Exoplanet Survey Satellite (TESS). Our analysis shows that TOI 122b has a radius of 2.72 ± 0.18 R⊕ and receives 8.8 ± 1.0 times Earth's bolometric insolation, and TOI 237b has a radius of 1.44±0.12 R⊕ and receives 3.7 ± 0.5 times Earth's insolation, straddling the 6.7 × Earth insolation that Mercury receives from the Sun. This makes these two of the cooler planets yet discovered by TESS, even on their 5.08 and 5.43 day orbits. Together, …

Spectral Properties Of Lunar Impact Melt Deposits From Moon Mineralogy Mapper (M3) Data, Catherine Neish, Kevin Cannon, Livio Tornabene, Roberta Flemming, Michael Zanetti, Eric Pilles

Earth Sciences Publications

Lunar impact melt deposits have unusual surface properties, unlike any measured terrestrial lava flow. Radar observations suggest that they are incredibly rough at decimeter scales, but they appear smooth in high-resolution, meter-scale optical images. The cause of their unusual surface roughness is unknown. In this work, we investigate the properties of impact melt deposits from seven lunar craters, ranging in size from 7.5 to 96 km in diameter, in an effort to understand the cause of their unique surface texture. We use data from the Lunar Reconnaissance Orbiter’s (LRO) Mini-RF instrument to characterize the small-scale roughness of the deposits, data …