Astrophysics and Astronomy Commons^™

Measurements Of The Branching Fractions Of The Semileptonic Decays Ξc0 → Ξ-ℓ+Νℓ And The Asymmetry Parameter Of Ξc0 → Ξ-Π+, Y. B. Li, C. P. Shen, I. Adachi, K. Adamczyk, H. Aihara, S. Al Said, D. M. Asner, T. Aushev, R. Ayad, V. Babu, P. Behera, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka, J. Biswal, G. Bonvicini, A. Bozek

Faculty and Student Publications

Using data samples of 89.5 and 711 fb-1 recorded at energies of s=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e+e- collider, we report measurements of branching fractions of semileptonic decays Ξc0→Ξ-ℓ+νℓ (ℓ=e or μ) and the CP-asymmetry parameter of Ξc0→Ξ-π+ decay. The branching fractions are measured to be B(Ξc0→Ξ-e+νe)=(1.31±0.04±0.07±0.38)% and B(Ξc0→Ξ-μ+νμ)=(1.27±0.06±0.10±0.37)%, and the decay parameter αΞπ is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξc0→Ξ-e+νe)/B(Ξc0→Ξ-μ+νμ) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter ACP=(αΞ-π++αΞ¯+π-)/(αΞ-π+-αΞ¯+π-)=0.024±0.052±0.014 is found …

Gw Ori: Circumtriple Rings And Planets, Jeremy L. Smallwood, Rebecca Nealon, Cheng Chen, Rebecca G. Martin, Jiaqing Bi, Ruobing Dong, Christophe Pinte

Physics & Astronomy Faculty Research

GW Ori is a hierarchical triple star system with a misaligned circumtriple protoplanetary disc. Recent Atacama Large Millimeter/submillimeter Array observations have identified three dust rings with a prominent gap at 100 au and misalignments between each of the rings. A break in the gas disc may be driven by the torque from either the triple star system or a planet that is massive enough to carve a gap in the disc. Once the disc is broken, the rings nodally precess on different time-scales and become misaligned. We investigate the origins of the dust rings by means of N-body integrations and …

Inelastic, Exchange, And Reactive Processes In Rovibrationally Excited Collisions Of Hd With H, Boyi Zhou, Benhui Yang, Balakrishnan Naduvalath, B. K. Kendrick, Maodu Chen, P. C. Stancil

Chemistry and Biochemistry Faculty Research

The HD molecule is an important coolant in early universe chemistry models and a tracer of H2 in star-forming regions. Rate coefficients for collisional excitation and de-excitation of HD rotational and vibrational levels form important ingredients in astrophysical models. While collisions with He, H2, and H are the most important, available data for H + HD collisions are largely limited to temperatures less than 1000 K for the vibrational ground state, low-lying rotational levels of the v = 1 HD vibrational level, or computed without reactive contributions. Here, through explicit quantum scattering calculations, we report extensive data for rovibrational transitions …

Ligo’S Quantum Response To Squeezed States, L. Mcculler, S. E. Dwyer, A. C. Green, Haocun Yu, K. Kuns, L. Barsotti, C. D. Blair, D. D. Brown, A. Effler, Karla E. Ramirez

Physics & Astronomy Faculty Publications

Gravitational wave interferometers achieve their profound sensitivity by combining a Michelson interferometer with optical cavities, suspended masses, and now, squeezed quantum states of light. These states modify the measurement process of the LIGO, VIRGO and GEO600 interferometers to reduce the quantum noise that masks astrophysical signals; thus, improvements to squeezing are essential to further expand our gravitational view of the Universe. Further reducing quantum noise will require both lowering decoherence from losses as well more sophisticated manipulations to counter the quantum back-action from radiation pressure. Both tasks require fully understanding the physical interactions between squeezed light and the many components …

Hst Pancet Program: A Complete Near-Uv To Infrared Transmission Spectrum For The Hot Jupiter Wasp-79b, Alexander D. Rathcke, Ryan J. Macdonald, Joanna K. Barstow, Jayesh M. Goyal, Mercedes Lopez-Morales, João M. Mendonça, Jorge Sanz-Forcada, Gregory W. Henry, David K. Sing, Munazza K. Alam, Nikole K. Lewis, Katy L. Chubb, Jake Taylor, Nikolay Nikolov, Lars A. Buchhave

Information Systems and Engineering Management Research Publications

We present a new optical transmission spectrum of the hot Jupiter WASP-79b. We observed three transits with the STIS instrument mounted on the Hubble Space Telescope (HST), spanning 0.3–1.0 μm. Combining these transits with previous observations, we construct a complete 0.3–5.0 μm transmission spectrum of WASP-79b. Both HST and ground-based observations show decreasing transit depths toward blue wavelengths, contrary to expectations from Rayleigh scattering or hazes. We infer atmospheric and stellar properties from the full near-UV to infrared transmission spectrum of WASP-79b using three independent retrieval codes, all of which yield consistent results. Our retrievals confirm previous detections of H2O …

Erratum: Searches For Continuous Gravitational Waves From Nine Young Supernova Remnants (Apj (2015) 813 (39) Doi: 10.1088/0004-637x/813/1/39), J. Aasi, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, A. Ain, P. Ajith, Tiffany Z. Summerscales

Faculty Publications

Equation (7) of the published article (Aasi et al. 2015) is in error; it should read (Equation presented). The upper limits on ò presented in the published article are unaffected by this error. Equation (8) of the published article is in error; it should read (Equation presented) The upper limits on α presented in Figure 3 and Table 4 of the published article were computed incorrectly. The revised Figure 3 (bottom) shows the corrected upper limits on α for the G266.2-1.2 (Vela Jr.) wide search. The revised Table 4 is provided here. The correct lowest upper limit on α (quoted …

Strong Inclination Pacing Of Climate In Late Triassic Low Latitudes Revealed By The Earth-Saturn Tilt Cycle, Miranda Margulis-Ohnuma, Jessica Whiteside, Paul Olsen

The Yale Undergraduate Research Journal

Gravitational interactions among masses in the solar system are recorded in Earth’s paleoclimate history because variations in the geometry of Earth’s orbit and axial orientation modulate insolation. However, astronomical models are unreliable before ~50 Ma due to the chaotic nature of the solar system and therefore must be constrained using geological observations. Here, we use environmental proxies from paleo-tropical Late Triassic lake deposits of the Newark Rift Basin to identify and tune to previously undescribed strong variations in orbital inclination. Tuning to the 173 kyr Earth-Saturn inclination cycle, theoretically stable due to the high mass of Saturn, reveals both other …

Mapping The Gravitational-Wave Sky With Lisa: A Bayesian Spherical Harmonic Approach, Sharan Banagiri, Alexander Criswell, Tommy Kuan, Vuk Mandic, Joseph D. Romano, Stephen R. Taylor

Physics & Astronomy Faculty Publications

The millihertz gravitational-wave frequency band is expected to contain a rich symphony of signals with sources ranging from Galactic white dwarf binaries to extreme mass ratio inspirals. Many of these gravitational-wave signals will not be individually resolvable. Instead, they will incoherently add to produce stochastic gravitational-wave confusion noise whose frequency content will be governed by the dynamics of the sources. The angular structure of the power of the confusion noise will be modulated by the distribution of the sources across the sky. Measurement of this structure can yield important information about the distribution of sources on Galactic and extragalactic scales, …

Direct H-He Chemical Association In Superionic Feo2H2He At Deep-Earth Conditions, Jurong Zhang, Hanyu Liu, Yanming Ma, Changfeng Chen

Physics & Astronomy Faculty Research

Hydrogen and helium are known to play crucial roles in geological and astrophysical environments; however, they are inert toward each other across wide pressure-temperature (P-T) conditions. Given their prominent presence and influence on the formation and evolution of celestial bodies, it is of fundamental interest to explore the nature of interactions between hydrogen and helium. Using an advanced crystal structure search method, we have identified a quaternary compound FeO₂H₂He stabilized in a wide range of P-T conditions. Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO₂H₂He hosting liquid-like …

Measurement Of The Masses And Widths Of The Σc (2455)+ And Σc (2520)+ Baryons, J. Yelton, I. Adachi, J. K. Ahn, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka

Faculty and Student Publications

Using 980 fb-1 of data collected with the Belle detector operating at the KEKB asymmetric-energy e+e- collider, we report the measurements of the masses, and the first measurements of the instrinsic widths, of the ςc(2455)+ and ςc(2520)+ charmed baryons. We find M(ςc(2455)+)-M(Λc+)=166.17±0.05-0.07+0.16 MeV/c2, Γ(ςc(2455)+)=2.3±0.3±0.3 MeV/c2, M(ςc(2520)+)-M(Λc+)=230.9±0.5-0.1+0.5 MeV/c2, and Γ(ςc(2520)+)=17.2-2.1-0.7+2.3+3.1 MeV/c2, where the uncertainties are statistical and systematic, respectively. These measurements can be used to test models of the underlying quark structure of the ςc states.

Measurement Of Branching Fractions And Search For Cp Violation In D 0 → Π + Π − Η, D 0 → K + K − Η, And D 0 → Φη At Belle, L. K. Li, A. J. Schwartz, K. Kinoshita, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, J. Bennett, M. Bessner, T. Bilka, J. Biswal, A. Bobrov

Faculty and Student Publications

We measure the branching fractions and CP asymmetries for the singly Cabibbo-suppressed decays D0 → π+π−η, D0 → K+K−η, and D0 → ϕη, using 980 fb−1 of data from the Belle experiment at the KEKB e+e− collider. We obtainB(D0→π+π−η)=[1.22±0.02(stat)±0.02(syst)±0.03(Bref)]×10−3,B(D0→K+K−η)=[1.80−0.06+0.07(stat)±0.04(syst)±0.05(Bref)]×10−4,B(D0→ϕη)=[1.84±0.09(stat)±0.06(syst)±0.05(Bref)]×10−4, where the third uncertainty (Bref) is from the uncertainty in the branching fraction of the reference mode D0 → K−π+η. The color-suppressed decay D0 → ϕη is observed for the first time, with very high significance. The results for the CP asymmetries areACP(D0π+π−η)=[0.9±1.2(stat)±0.5(syst)]%,ACP(D0→K+K−η)=[−1.4±3.3(stat)±1.1(syst)]%,ACP(D0→ϕη)=[−1.9±4.4(stat)±0.6(syst)]%. The results for D0 → π+π−η are a significant improvement over previous results. The branching fraction and ACP …

Axionlike Particles Resolve The B →Πk And G-2 Anomalies, Bhubanjyoti Bhattacharya, Alakabha Datta, Danny Marfatia, Soumitra Nandi, John Waite

Faculty and Student Publications

We offer a new solution to an old puzzle in the penguin-dominated B→πK decays. The puzzle is the inconsistency among the measurements of the branching ratios and CP asymmetries of the four B→πK decays: B+→π+K0, B+→π0K+, Bd0→π-K+, Bd0→π0K0. We solve the B→πK puzzle by considering the effect of an axionlike particle (ALP) that mixes with the π0 and has mass close to the π0 mass. We show that the ALP can also explain the anomalies in the electron and muon anomalous magnetic moments.

Nnetfix: An Artificial Neural Network-Based Denoising Engine For Gravitational-Wave Signals, Kentaro Mogushi, Ryan Quitzow-James, Marco Cavaglià, Sumeet Kulkarni, Fergus Hayes

Faculty and Student Publications

Instrumental and environmental transient noise bursts in gravitational-wave (GW) detectors, or glitches, may impair astrophysical observations by adversely affecting the sky localization and the parameter estimation of GW signals. Denoising of detector data is especially relevant during low-latency operations because electromagnetic follow-up of candidate detections requires accurate, rapid sky localization and inference of astrophysical sources. NNETFIX is a machine learning, artificial neural network-based algorithm designed to estimate the data containing a transient GW signal with an overlapping glitch as though the glitch was absent. The sky localization calculated from the denoised data may be significantly more accurate than the sky …

Toi-674b: An Oasis In The Desert Of Exo-Neptunes Transiting A Nearby M Dwarf, F. Murgas, N. Astudillo-Defru, X. Bonfils, I. Crossfield, J. M. Almenara, J. Livingston, K. G. Stassun, J. Korth, J. Orell-Miquel, G. Morello, J. D. Eastman, J. J. Lissauer, S. R. Kane, F. Y. Morales, M. W. Werner, V. Gorjian, B. Benneke, D. Dragomir, E. C. Matthews, S. B. Howell, D. Ciardi, E. Gonzales, R. Matson, C. Beichman, J. Schlieder, K. A. Collins, K. I. Collins, Eric L.N. Jensen, P. Evans, F. J. Pozuelos, M. Gillon, E. Jehin, K. Barkaoui, E. Artigau, F. Bouchy, D. Charbonneau, X. Delfosse, R. F. Díaz, R. Doyon, P. Figueira, T. Forveille, C. Lovis, C. Melo, G. Gaisné, F. Pepe, N. C. Santos, D. Ségransan, S. Udry, R. F. Goeke, A. M. Levine, E. V. Quintana, N. M. Guerrero, I. Mireles, D. A. Caldwell, P. Tenenbaum, C. E. Brasseur, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. Winn, J. M. Jenkins

Physics & Astronomy Faculty Works

Context. The NASA mission TESS is currently doing an all-sky survey from space to detect transiting planets around bright stars. As part of the validation process, the most promising planet candidates need to be confirmed and characterized using follow-up observations. Aims. In this article, our aim is to confirm the planetary nature of the transiting planet candidate TOI-674b using spectroscopic and photometric observations. Methods. We use TESS, Spitzer, ground-based light curves, and HARPS spectrograph radial velocity measurements to establish the physical properties of the transiting exoplanet candidate TOI-674b. We perform a joint fit of the light …

The X-Rays Wind Connection In Pg 2112+059, C. Saez, W. N. Brandt, F. E. Bauer, G. Chartas, T. Misawa, F. Hamann, Sarah C. Gallagher

Physics and Astronomy Publications

We study the connection between the X-ray and ultraviolet (UV) properties of the broad absorption line (BAL) wind in the highly X-ray variable quasar PG 2112+059 by comparing Chandra-ACIS data with contemporaneous UV HST/STIS spectra in three different epochs. We observe a correlation whereby an increase in the equivalent widths (EWs) of the BALs is accompanied by a redder UV spectrum. The growth in the BAL EWs is also accompanied by a significant dimming in soft X-ray emission (≳2, keV), consistent with increased absorption. Variations in the hard X-ray emission (≳2, keV) are only accompanied by minor spectral variations of …

Toi-1231 B: A Temperate, Neptune-Sized Planet Transiting The Nearby M3 Dwarf Nltt 24399, J. A. Burt, D. Dragomir, P. Mollière, A. Youngblood, A. García Muñoz, J. Mccann, L. Kreidberg, C. X. Huang, K. A. Collins, J. D. Eastman, L. Abe, J. M. Almenara, I. J. M. Crossfield, C. Ziegler, J. E. Rodriguez, E. E. Mamajek, K. G. Stassun, S. P. Halverson, S. Villanueva Jr., R. P. Butler, S. X. Wang, R. P. Schwarz, G. R. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, A. Agabi, X. Bonfils, D. Ciardi, M. Cointepas, J. D. Crane, N. Crouzet, G. Dransfield, F. Feng, E. Furlan, T. Guillot, A. F. Gupta, S. B. Howell, Eric L.N. Jensen, N. Law, A. W. Mann, W. Marie-Sainte, R. A. Matson, E. C. Matthews, D. Mékarnia, J. Pepper, N. Scott, S. A. Shectman, J. E. Schlieder, F.-X. Schmider, D. J. Stevens, J. K. Teske, A. H. M. J. Triaud, D. Charbonneau, Z. K. Berta-Thompson, C. J. Burke, T. Daylan, T. Barclay, B. Wohler, C. E. Brasseur

Physics & Astronomy Faculty Works

We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby (d = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite and followed up with observations from the Las Cumbres Observatory and the Antarctica Search for Transiting ExoPlanets program. Combining the photometric data sets, we find that the newly discovered planet has a radius of 3.65 (+0.16)/(-0.15) R_⊕ and an orbital period of 24.246 days. Radial velocity measurements obtained with the Planet Finder Spectrograph on the Magellan Clay telescope confirm …

Directly Determined Properties Of Hd 97658 From Interferometric Observations, Tyler G. Ellis, Tabetha Boyajian, Kaspar Von Braun, Roxanne Ligi, Denis Mourard, Diana Dragomir, Gail H. Schaefer, Christopher D. Farrington

Faculty Publications

We conducted interferometric observations with the CHARA Array of transiting super-Earth host HD 97658 and measured its limb-darkened angular diameter to be theta(LD) = 0.314 +/- 0.004 mas. The combination of the angular diameter with the Gaia EDR3 parallax value with zero-point correction (pi = 46.412 +/- 0.022 mas, d =21.546 +/- 0.011 pc) yields a physical radius of R-star = 0.728 +/- 0.008 R-circle dot. We also measured the bolometric flux of the star to be F-bol = 2.42 +/- 0.05 x 10(-8) erg s(-1) cm(-2), which, together with angular size, allows a measurement of the effective temperature T-eff …

A Unified Approach To M Dwarf Ages, Rocio Kiman

Dissertations, Theses, and Capstone Projects

Estimating ages of M dwarfs, the lowest mass stars in the Galaxy, is a current unresolved problem in Astrophysics. This dissertation focuses on developing a method to estimate ages for M dwarfs. This method consists of combining different age indicators in a Bayesian framework to achieve a precise age measurement. The age indicators I use are: 1) position in the color-magnitude diagram which is a proxy for effective temperature and luminosity, 2) movement of the stars in the Galaxy, or its 3D kinematics, 3) magnetic activity, measured by the Halpha emission line of the spectrum. In this dissertation I analyze …

Galaxy And Mass Assembly (Gama), U. Sureshkumar, A. Durkalec, A. Pollo, M. Bilicki, J. Loveday, D. J. Farrow, Benne Holwerda, A. M. Hopkins, J. Liske, K. A. Pimbblet, E. N. Taylor, A. H. Wright

Faculty and Staff Scholarship

Context. Galaxies are biased tracers of the underlying network of dark matter. The strength of this bias depends on various galaxy properties and on redshift. One of the methods used to study these dependences of the bias is measurement of galaxy clustering. Such studies are made using galaxy samples from various catalogues, which frequently bear their own problems related to sample selection methods. It is therefore crucial to understand how sample choice influences clustering measurements and which galaxy property is the most direct tracer of the galaxy environment.

Aims. We investigate how different galaxy properties, such as luminosities in the …

Solar Flares As Observed In The Low Frequency Microwave Gyrosynchrotron Emission, Shaheda Begum Shaik

Dissertations

Solar flares involve the sudden catastrophic release of magnetic energy stored in the Sun’s corona. This dissertation focuses on investigating the low frequency, optically-thick gyrosynchrotron emission during solar flares for its spatial and spectral dynamics, characteristics, and role in the flare process.

The first part of this dissertation first addresses the spectral dynamics and characteristics of the source morphology. The high-resolution spectra of a set of microwave bursts observed by the Expanded Owens Valley Solar Array (EOVSA) during its commissioning phase in the 2.5-18 GHz frequency range with 1-s time resolution are presented here. Out of the 12 events analyzed …