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Measurement Of The Double-Differential Muon-Neutrino Charged-Current Inclusive Cross Section In The Nova Near Detector, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, M. Baird, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, B. Behera, R. Bernstein, V. Bhatnagar, D. Bhattarai, B. Bhuyan, Roberto Petti, Et. Al. 2023 University of South Carolina

Measurement Of The Double-Differential Muon-Neutrino Charged-Current Inclusive Cross Section In The Nova Near Detector, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, M. Baird, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, B. Behera, R. Bernstein, V. Bhatnagar, D. Bhattarai, B. Bhuyan, Roberto Petti, Et. Al.

Faculty Publications

We report cross-section measurements of the final-state muon kinematics for νμ charged-current interactions in the NOvA near detector using an accumulated 8.09×1020 protons on target in the NuMI beam. We present the results as a double-differential cross section in the observed outgoing muon energy and angle, as well as single-differential cross sections in the derived neutrino energy, Eν, and square of the four-momentum transfer, Q2. We compare the results to inclusive cross-section predictions from various neutrino event generators via χ2 calculations using a covariance matrix that accounts for bin-to-bin correlations of systematic uncertainties. …


Estimating The Oblateness Of Dark Matter Halos Using Neutral Hydrogen Velocity Dispersion, Stacy S. McGaugh 2023 Case Western Reserve University

Estimating The Oblateness Of Dark Matter Halos Using Neutral Hydrogen Velocity Dispersion, Stacy S. Mcgaugh

Faculty Scholarship

We derive the oblateness parameter q of the dark matter halo of a sample of gas-rich, face-on disk galaxies. We have assumed that the halos are triaxial in shape but their axes in the disk plane (a and b) are equal, so that q = c/a measures the halo flattening. We have used the H i velocity dispersion, derived from the stacked H i emission lines and the disk surface density, determined from the H i flux distribution, to determine the disk potential and the halo shape at the R 25 and 1.5R 25 radii. We have applied our model …


The Quantitative Microanalysis Explorer: Introducing Web-Based Visualization For Optical, Electron, And Quantitative X-Ray Maps For Studying Lunar Samples, Angelina Minocha 2023 Washington University in St. Louis

The Quantitative Microanalysis Explorer: Introducing Web-Based Visualization For Optical, Electron, And Quantitative X-Ray Maps For Studying Lunar Samples, Angelina Minocha

Senior Honors Papers / Undergraduate Theses

Modern sample imaging techniques produce data in the form of large mosaics, wherein every pixel contains valuable mineralogical information. These heavy data files are challenging for most computers to load and process, furthermore access to lunar and other extraterrestrial samples is limited. We developed the QME Tool to display optical, electron, and quantitative x-ray maps in conjunction with one another to overcome these challenges and advance mineralogy data presentation and analysis. The images and quantitative data was collected using specialized techniques, followed by an extensive image co-registration process. The interface was developed using OpenSeadragon, “An open-source, web-based viewer for high-resolution …


Stellar Binaries And Post-Merger Evolution: A Framework For Stellar Evolution And Nucleosynthesis In R Coronae Borealis Stars, Bradley Munson 2023 Louisiana State University and Agricultural and Mechanical College

Stellar Binaries And Post-Merger Evolution: A Framework For Stellar Evolution And Nucleosynthesis In R Coronae Borealis Stars, Bradley Munson

LSU Doctoral Dissertations

We have developed a framework for simulating binary stars through all three relevant
timescales: the dynamical merger, thermal, and nuclear evolution. The framework begins by simulating a dynamical merger in a 3-dimensional hydrodynamics adaptive mesh refinement code, Octo-Tiger, and performing a spherical averaging calculation to map the post-merger remnant into the 1-dimensional stellar evolution code, MESA. In this work, we primarily utilize this framework for simulating double white dwarf mergers, which are believed to be the progenitor to R Coronae Borealis (RCB) stars. We evolve the post-merger in MESA and compare the computed surface abundances to those observed …


Powerful Radio Sources In The Southern Sky. I. Optical Identifications, Francesco Massaro, S. V. White, A. García-Pérez, A. Jimenez-Gallardo, A. Capetti, C. C. Cheung, W. R. Forman, C. Mazzucchelli, A. Paggi, Juan P. Madrid 2023 The University of Texas Rio Grande Valley

Powerful Radio Sources In The Southern Sky. I. Optical Identifications, Francesco Massaro, S. V. White, A. García-Pérez, A. Jimenez-Gallardo, A. Capetti, C. C. Cheung, W. R. Forman, C. Mazzucchelli, A. Paggi, Juan P. Madrid

Physics & Astronomy Faculty Publications

Since the early sixties, our view of radio galaxies and quasars has been drastically shaped by discoveries made thanks to observations of radio sources listed in the Third Cambridge Catalog and its revised version (3CR). However, the largest fraction of data collected to date on 3CR sources was performed with relatively old instruments, rarely repeated and/or updated. Importantly, the 3CR contains only objects located in the Northern Hemisphere, thus having limited access to new and innovative astronomical facilities. To mitigate these limitations, we present a new catalog of powerful radio sources visible from the Southern Hemisphere, extracted from the GLEAM …


The Puzzle Of The Formation Of T8 Dwarf Ross 458c, Josefine Gaarn, Ben Burningham, Jacqueline K. Faherty, Channon Visscher, Mark S. Marley, Eileen C. Gonzales, Emily Calamari, Daniella Bardalez Gagliuffi, Roxana Lupu, Richard Freedman 2023 Dordt University

The Puzzle Of The Formation Of T8 Dwarf Ross 458c, Josefine Gaarn, Ben Burningham, Jacqueline K. Faherty, Channon Visscher, Mark S. Marley, Eileen C. Gonzales, Emily Calamari, Daniella Bardalez Gagliuffi, Roxana Lupu, Richard Freedman

Faculty Work Comprehensive List

At the lowest masses, the distinction between brown dwarfs and giant exoplanets is often blurred and literature classifications rarely reflect the deuterium burning boundary. Atmospheric characterization may reveal the extent to which planetary formation pathways contribute to the population of very low mass brown dwarfs, by revealing whether their abundance distributions differ from those of the local field population or, in the case of companions, their primary stars. The T8 dwarf Ross 458c is a possible planetary-mass companion to a pair of M dwarfs, and previous work suggests that it is cloudy. We here present the results of the retrieval …


A Candidate Magnetic Helium-Core White Dwarf In The Globular Cluster Ngc 6397, Manuel Pichardo Marcano, Liliana E. Rivera Sandoval, Thomas J. Maccarone, Rene D. Rohrmann, Craig O. Heinke, Diogo Belloni, Leandro G. Althaus, Arash Bahramian 2023 The University of Texas Rio Grande Valley

A Candidate Magnetic Helium-Core White Dwarf In The Globular Cluster Ngc 6397, Manuel Pichardo Marcano, Liliana E. Rivera Sandoval, Thomas J. Maccarone, Rene D. Rohrmann, Craig O. Heinke, Diogo Belloni, Leandro G. Althaus, Arash Bahramian

Physics & Astronomy Faculty Publications

We report a peculiar variable blue star in the globular cluster (GC) NGC 6397, using Hubble Space Telescope optical imaging. Its position in the colour–magnitude diagrams and its spectrum are consistent with this star being a helium-core white dwarf (He WD) in a binary system. The optical light curve shows a periodicity at 18.5 h. We argue that this periodicity is due to the rotation of the WD and possibly due to magnetic spots on the surface of the WD. This would make this object the first candidate magnetic He WD in any GC, and the first candidate magnetic WD …


Stellar Atmosphere Models For Select Veritas Stellar Intensity Interferometry Targets, Jackson Ladd Sackrider, Jason P. Aufdenberg, Katelyn Sonnen 2023 Embry-Riddle Aeronautical University

Stellar Atmosphere Models For Select Veritas Stellar Intensity Interferometry Targets, Jackson Ladd Sackrider, Jason P. Aufdenberg, Katelyn Sonnen

Beyond: Undergraduate Research Journal

Since 2020 the Very Energetic Radiation Imaging Telescope Array System (VERITAS) has observed 48 stellar targets using the technique of Stellar Intensity Interferometry (SII). Angular diameter measurements by VERITAS SII (VSII) in a waveband near 400 nm complement existing angular diameter measurements in the near-infrared. VSII observations will test fundamental predictions of stellar atmosphere models and should be more sensitive to limb darkening and gravity darkening effects than measurements in the near-IR, however, the magnitude of this difference has not been systematically explored in the literature. In order to investigate the synthetic interferometric (as well as spectroscopic) appearance of stars …


Wallaby Pilot Survey: Hydra Cluster Galaxies Uv And H I Morphometrics, Benne W. Holwerda, Frank Bigiel, Albert Bosma, Helene M. Courtois, Nathan Deg, Helga Dénes, Ahmed Elagali, Bi-Qing For, Baerbel Koribalski, Denis A. Leahy, Karen Lee-Waddell, Ángel R. López-Sánchez, Se-Heon Oh, Tristan N. Reynolds, Jonghwan Rhee, Kristine Spekkens, Jing Wang, Tobias Westmeier, O Ivy Wong 2023 University of Louisville

Wallaby Pilot Survey: Hydra Cluster Galaxies Uv And H I Morphometrics, Benne W. Holwerda, Frank Bigiel, Albert Bosma, Helene M. Courtois, Nathan Deg, Helga Dénes, Ahmed Elagali, Bi-Qing For, Baerbel Koribalski, Denis A. Leahy, Karen Lee-Waddell, Ángel R. López-Sánchez, Se-Heon Oh, Tristan N. Reynolds, Jonghwan Rhee, Kristine Spekkens, Jing Wang, Tobias Westmeier, O Ivy Wong

Faculty and Staff Scholarship

Galaxy morphology in atomic hydrogen (H I) and in the ultraviolet (UV) are closely linked. This has motivated their combined use to quantify morphology over the full H I disc for both H I and UV imaging. We apply galaxy morphometrics: concentration, asymmetry, gini, M20 and multimode-intensity-deviation statistics to the first moment-0 maps of the WALLABY Survey of galaxies in the hydra cluster centre. Taking advantage of this new H I survey, we apply the same morphometrics over the full H I extent on archival GALEX FUV and NUV data to explore how well H I truncated, extended ultraviolet …


Characterization Of A Set Of Small Planets With Tess And Cheops And An Analysis Of Photometric Performance, D. Oddo, D. Dragomir, A. Brandeker, H. P. Osborn, K. Collins, K. G. Stassun, N. Astudillo-Defru, A. Bieryla, S. B. Howell, D. R. Ciardi, S. Quinn, J. M. Almenara, C. Briceño, K. I. Collins, K. D. Colón, D. M. Conti, N. Crouzet, E. Furlan, T. Gan, C. L. Gnilka, R. F. Goeke, E. Gonzales, M. Harris, J. M. Jenkins, Eric L.N. Jensen, D. Latham, N. Law, M. B. Lund, A. W. Mann, B. Massey, F. Murgas, G. Ricker, H. M. Relles, P. Rowden, R. P. Schwarz, J. Schlieder, A. Shporer, S. Seager, G. Srdoc, G. Torres, J. D. Twicken, R. Vanderspek, J. N. Winn, C. Ziegler 2023 Swarthmore College

Characterization Of A Set Of Small Planets With Tess And Cheops And An Analysis Of Photometric Performance, D. Oddo, D. Dragomir, A. Brandeker, H. P. Osborn, K. Collins, K. G. Stassun, N. Astudillo-Defru, A. Bieryla, S. B. Howell, D. R. Ciardi, S. Quinn, J. M. Almenara, C. Briceño, K. I. Collins, K. D. Colón, D. M. Conti, N. Crouzet, E. Furlan, T. Gan, C. L. Gnilka, R. F. Goeke, E. Gonzales, M. Harris, J. M. Jenkins, Eric L.N. Jensen, D. Latham, N. Law, M. B. Lund, A. W. Mann, B. Massey, F. Murgas, G. Ricker, H. M. Relles, P. Rowden, R. P. Schwarz, J. Schlieder, A. Shporer, S. Seager, G. Srdoc, G. Torres, J. D. Twicken, R. Vanderspek, J. N. Winn, C. Ziegler

Physics & Astronomy Faculty Works

The radius valley carries implications for how the atmospheres of small planets form and evolve, but this feature is visible only with highly precise characterizations of many small planets. We present the characterization of nine planets and one planet candidate with both NASA TESS and ESA CHEOPS observations, which adds to the overall population of planets bordering the radius valley. While five of our planets—TOI 118 b, TOI 262 b, TOI 455 b, TOI 560 b, and TOI 562 b—have already been published, we vet and validate transit signals as planetary using follow-up observations for four new TESS planets, including …


Tess Discovery Of Twin Planets Near 2:1 Resonance Around Early M Dwarf Toi 4342, E. Tey, C. X. Huang, M. Kunimoto, A. Vanderburg, A. Shporer, S. N. Quinn, G. Zhou, K. A. Collins, K. I. Collins, Eric L.N. Jensen, R. P. Schwarz, R. Sefako, T. Gan, E. Furlan, C. L. Gnilka, S. B. Howell, K. V. Lester, C. Ziegler, C. Briceño, N. Law, A. W. Mann, G. R. Ricker, R. K. Vanderspek, D. W. Latham, S. Seager, J. M. Jenkins, J. N. Winn, D. A. Caldwell, D. Charbonneau, C. J. Burke, Z. Essack 2023 Swarthmore College

Tess Discovery Of Twin Planets Near 2:1 Resonance Around Early M Dwarf Toi 4342, E. Tey, C. X. Huang, M. Kunimoto, A. Vanderburg, A. Shporer, S. N. Quinn, G. Zhou, K. A. Collins, K. I. Collins, Eric L.N. Jensen, R. P. Schwarz, R. Sefako, T. Gan, E. Furlan, C. L. Gnilka, S. B. Howell, K. V. Lester, C. Ziegler, C. Briceño, N. Law, A. W. Mann, G. R. Ricker, R. K. Vanderspek, D. W. Latham, S. Seager, J. M. Jenkins, J. N. Winn, D. A. Caldwell, D. Charbonneau, C. J. Burke, Z. Essack

Physics & Astronomy Faculty Works

With data from the Transiting Exoplanet Survey Satellite (TESS), we showcase improvements to the MIT Quick Look Pipeline (QLP) through the discovery and validation of a multiplanet system around M dwarf TOI 4342 (Tmag = 11.032, M⋆ = 0.63 M⊙, R⋆ = 0.60 R⊙, Teff = 3900 K, d = 61.54 pc). With updates to QLP, including a new multiplanet search, as well as faster cadence data from TESS's First Extended Mission, we discovered two sub-Neptunes (Rb = 2.266 (+0.038)/(-0.038) R⊕ and Rc = 2.415 (+0.043)/(-0.040) R …


The Jwst Early-Release Science Program For Direct Observations Of Exoplanetary Systems Ii: A 1 To 20 Μm Spectrum Of The Planetary-Mass Companion Vhs 1256-1257 B, Brittany E. Miles, Beth A. Biller, Polychronis Patapis, Kadin Worthen, Emily Rickman, Kielan K.W. Hoch, Andrew Skemer, Marshall D. Perrin, Niall Whiteford, Christine H. Chen, B. Sargent, Sagnick Mukherjee, Caroline V. Morley, Sarah E. Moran, Mickael Bonnefoy, Simon Petrus, Aarynn L. Carter, Elodie Choquet, Sasha Hinkley, Kimberly Ward-Duong, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Laurent Pueyo, Shrishmoy Ray, Steph Sallum, Karl R. Stapelfeldt, Jordan M. Stone, Jason J. Wang, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita 2023 University of California, Santa Cruz

The Jwst Early-Release Science Program For Direct Observations Of Exoplanetary Systems Ii: A 1 To 20 Μm Spectrum Of The Planetary-Mass Companion Vhs 1256-1257 B, Brittany E. Miles, Beth A. Biller, Polychronis Patapis, Kadin Worthen, Emily Rickman, Kielan K.W. Hoch, Andrew Skemer, Marshall D. Perrin, Niall Whiteford, Christine H. Chen, B. Sargent, Sagnick Mukherjee, Caroline V. Morley, Sarah E. Moran, Mickael Bonnefoy, Simon Petrus, Aarynn L. Carter, Elodie Choquet, Sasha Hinkley, Kimberly Ward-Duong, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Laurent Pueyo, Shrishmoy Ray, Steph Sallum, Karl R. Stapelfeldt, Jordan M. Stone, Jason J. Wang, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita

Astronomy: Faculty Publications

We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a (∼8″, a = 150 au), young, planetary-mass companion that shares photometric colors and spectroscopic features with the directly imaged exoplanets HR 8799c, d, and e. As an L-to-T transition object, VHS 1256 b exists along the region of the color-magnitude diagram where substellar atmospheres transition from cloudy to clear. We observed VHS 1256 b with JWST's NIRSpec IFU and MIRI MRS modes for coverage from 1 to 20 μm at resolutions of ∼1000-3700. Water, methane, carbon monoxide, carbon dioxide, sodium, and potassium are …


The Tess Grand Unified Hot Jupiter Survey. Ii. Twenty New Giant Planets, S. W. Yee, J. N. Winn, J. D. Hartman, L. G. Bouma, G. Zhou, S. N. Quinn, D. W. Latham, A. Bieryla, J. E. Rodriguez, K. A. Collins, O. Alfaro, K. Barkaoui, C. Beard, A. A. Belinski, Z. Benkhaldoun, P. Benni, K. Bernacki, A. W. Boyle, R. P. Butler, D. A. Caldwell, A. Chontos, J. L. Christiansen, D. R. Ciardi, K. I. Collins, D. M. Conti, J. D. Crane, T. Daylan, C. D. Dressing, J. D. Eastman, Z. Essack, P. Evans, M. E. Everett, S. Fajardo-Acosta, R. Forés-Toribio, E. Furlan, M. Ghachoui, M. Gillon, C. Hellier, I. Helm, A. W. Howard, S. B. Howell, H. Isaacson, E. Jehin, J. M. Jenkins, Eric L.N. Jensen, J. F. Kielkopf, D. Laloum, N. Leonhardes-Barboza, P. Lewin, S. E. Logsdon, J. Lubin, M. B. Lund, M. G. MacDougall, A. W. Mann, N. A. Maslennikova, B. Massey, K. K. McLeod, J. A. Muñoz, P. Newman, V. Orlov, P. Plavchan, A. Popowicz, F. J. Pozuelos, T. A. Pritchard, D. J. Radford, M. Reefe, G. R. Ricker, A. Rudat, B. S. Safonov, R. P. Schwarz, H. Schweiker, N. J. Scott, S. Seager, S. A. Shectman, C. Stockdale, T.-G. Tan, J. K. Teske, N. B. Thomas, M. Timmermans, R. Vanderspek, D. Vermilion, D. Watanabe, L. M. Weiss, R. G. West, J. Van Zandt, M. Zejmo, C. Ziegler 2023 Swarthmore College

The Tess Grand Unified Hot Jupiter Survey. Ii. Twenty New Giant Planets, S. W. Yee, J. N. Winn, J. D. Hartman, L. G. Bouma, G. Zhou, S. N. Quinn, D. W. Latham, A. Bieryla, J. E. Rodriguez, K. A. Collins, O. Alfaro, K. Barkaoui, C. Beard, A. A. Belinski, Z. Benkhaldoun, P. Benni, K. Bernacki, A. W. Boyle, R. P. Butler, D. A. Caldwell, A. Chontos, J. L. Christiansen, D. R. Ciardi, K. I. Collins, D. M. Conti, J. D. Crane, T. Daylan, C. D. Dressing, J. D. Eastman, Z. Essack, P. Evans, M. E. Everett, S. Fajardo-Acosta, R. Forés-Toribio, E. Furlan, M. Ghachoui, M. Gillon, C. Hellier, I. Helm, A. W. Howard, S. B. Howell, H. Isaacson, E. Jehin, J. M. Jenkins, Eric L.N. Jensen, J. F. Kielkopf, D. Laloum, N. Leonhardes-Barboza, P. Lewin, S. E. Logsdon, J. Lubin, M. B. Lund, M. G. Macdougall, A. W. Mann, N. A. Maslennikova, B. Massey, K. K. Mcleod, J. A. Muñoz, P. Newman, V. Orlov, P. Plavchan, A. Popowicz, F. J. Pozuelos, T. A. Pritchard, D. J. Radford, M. Reefe, G. R. Ricker, A. Rudat, B. S. Safonov, R. P. Schwarz, H. Schweiker, N. J. Scott, S. Seager, S. A. Shectman, C. Stockdale, T.-G. Tan, J. K. Teske, N. B. Thomas, M. Timmermans, R. Vanderspek, D. Vermilion, D. Watanabe, L. M. Weiss, R. G. West, J. Van Zandt, M. Zejmo, C. Ziegler

Physics & Astronomy Faculty Works

NASA's Transiting Exoplanet Survey Satellite (TESS) mission promises to improve our understanding of hot Jupiters by providing an all-sky, magnitude-limited sample of transiting hot Jupiters suitable for population studies. Assembling such a sample requires confirming hundreds of planet candidates with additional follow-up observations. Here we present 20 hot Jupiters that were detected using TESS data and confirmed to be planets through photometric, spectroscopic, and imaging observations coordinated by the TESS Follow-up Observing Program. These 20 planets have orbital periods shorter than 7 days and orbit relatively bright FGK stars (10.9 < G < 13.0). Most of the planets are comparable in mass to Jupiter, although there are four planets with masses less than that of Saturn. TOI-3976b, the longest-period planet in our sample (P = 6.6 days), may be on a moderately eccentric orbit (e = 0.18 ± 0.06), while observations of the other …


Calculating MBh Scaling Relations For Agns Using 2d Galaxy Decomposition Software To Analyse Hst Images, Jewel A. Capili 2023 California Polytechnic State University, San Luis Obispo

Calculating MBh Scaling Relations For Agns Using 2d Galaxy Decomposition Software To Analyse Hst Images, Jewel A. Capili

Physics

This study uses the 2D galaxy decomposition software GALFIT developed by Dr. Chien Peng to analyse Hubble Space Telescope images of 14 Active Galactic Nuclei (AGNs) and obtain their M_BH-spheroid luminosity scaling relations for comparison with previous studies.


Aggregate Effects Of Proliferating Low-Earth-Orbit Objects And Implications For Astronomical Data Lost In The Noise, John C. Barentine, Aparna Venkatesan, Jessica Heim, James Lowenthal, Miroslav Kocifaj, Salvador Bará 2023 LLC

Aggregate Effects Of Proliferating Low-Earth-Orbit Objects And Implications For Astronomical Data Lost In The Noise, John C. Barentine, Aparna Venkatesan, Jessica Heim, James Lowenthal, Miroslav Kocifaj, Salvador Bará

Astronomy: Faculty Publications

The rising population of artificial satellites and associated debris in low-altitude orbits is increasing the overall brightness of the night sky, threatening ground-based astronomy as well as a diversity of stakeholders and ecosystems reliant on dark skies. We present calculations of the potentially large rise in global sky brightness from space objects in low Earth orbit, including qualitative and quantitative assessments of how professional astronomy may be affected. Debris proliferation is of special concern: we calculate that all log-decades in debris size contribute approximately the same amount of night sky radiance, so debris-generating events are expected to lead to a …


Correlating Changes In Spot Filling Factors With Stellar Rotation: The Case Of Lkca 4, Facundo Pérez Paolino, Jeffrey S. Bary, Michael S. Petersen, Kimberly Ward-Duong, Benjamin M. Tofflemire, Katherine B. Follette, Heidi Mach 2023 Colgate University

Correlating Changes In Spot Filling Factors With Stellar Rotation: The Case Of Lkca 4, Facundo Pérez Paolino, Jeffrey S. Bary, Michael S. Petersen, Kimberly Ward-Duong, Benjamin M. Tofflemire, Katherine B. Follette, Heidi Mach

Astronomy: Faculty Publications

We present a multi-epoch spectroscopic study of LkCa 4, a heavily spotted non-accreting T Tauri star. Using SpeX at NASA’s Infrared Telescope Facility (IRTF), 12 spectra were collected over five consecutive nights, spanning ≈1.5 stellar rotations. Using the IRTF SpeX Spectral Library, we constructed empirical composite models of spotted stars by combining a warmer (photosphere) standard star spectrum with a cooler (spot) standard weighted by the spot filling factor, f spot. The best-fit models spanned two photospheric component temperatures, T phot = 4100 K (K7V) and 4400 K (K5V), and one spot component temperature, T spot = 3060 K (M5V) …


Direct Discovery Of The Inner Exoplanet In The Hd 206893 System: Evidence For Deuterium Burning In A Planetary-Mass Companion, S. Hinkley, S. Lacour, G. D. Marleau, A. M. Lagrange, J. J. Wang, J. Kammerer, A. Cumming, M. Nowak, L. Rodet, T. Stolker, W. O. Balmer, S. Ray, M. Bonnefoy, P. Mollière, C. Lazzoni, G. Kennedy, C. Mordasini, R. Abuter, S. Aigrain, A. Amorim, R. Asensio-Torres, C. Babusiaux, M. Benisty, J. P. Berger, H. Beust, S. Blunt, A. Boccaletti, Kimberly Ward-Huong, et al 2023 University of Exeter

Direct Discovery Of The Inner Exoplanet In The Hd 206893 System: Evidence For Deuterium Burning In A Planetary-Mass Companion, S. Hinkley, S. Lacour, G. D. Marleau, A. M. Lagrange, J. J. Wang, J. Kammerer, A. Cumming, M. Nowak, L. Rodet, T. Stolker, W. O. Balmer, S. Ray, M. Bonnefoy, P. Mollière, C. Lazzoni, G. Kennedy, C. Mordasini, R. Abuter, S. Aigrain, A. Amorim, R. Asensio-Torres, C. Babusiaux, M. Benisty, J. P. Berger, H. Beust, S. Blunt, A. Boccaletti, Kimberly Ward-Huong, Et Al

Astronomy: Faculty Publications

Aims. HD 206893 is a nearby debris disk star that hosts a previously identified brown dwarf companion with an orbital separation of ~ 10 au. Long-Term precise radial velocity (RV) monitoring, as well as anomalies in the system proper motion, has suggested the presence of an additional, inner companion in the system. Methods. Using information from ongoing precision RV measurements with the HARPS spectrograph, as well as Gaia host star astrometry, we have undertaken a multi-epoch search for the purported additional planet using the VLTI/GRAVITY instrument. Results. We report a high-significance detection over three epochs of the companion HD 206893c, …


Merging Black Holes: Assessing The Performance Of Two Analytic Gravitational Waves Models, Dillon Buskirk, Maria Babiuc-Hamilton 2023 Marshall University

Merging Black Holes: Assessing The Performance Of Two Analytic Gravitational Waves Models, Dillon Buskirk, Maria Babiuc-Hamilton

Physics Faculty Research

Merging black holes produce the loudest signal in the detectors. However, this is the most difficult signal to accurately predict with analytical techniques. Only computer simulations can account for the nonlinear physics during the collision, but they are inherently complex, costly, and affected by numerical errors. In order to bypass this problem, two analytical models for the merger have been developed: the Implicit Rotating Source (IRS) and the newer Backwards one Body (BoB). In this work, we assess the performance of the BoB model by comparing it with the older IRS model and with the numerical data, identifying its strengths …


Evolution Of Coronal Magnetic Field Parameters During X5.4 Solar Flare, Seth H. Garland, Benjamin F. Akers, Vasyl B. Yurchyshyn, Robert D. Loper, Daniel J. Emmons 2023 Air Force Institute of Technology

Evolution Of Coronal Magnetic Field Parameters During X5.4 Solar Flare, Seth H. Garland, Benjamin F. Akers, Vasyl B. Yurchyshyn, Robert D. Loper, Daniel J. Emmons

Faculty Publications

The coronal magnetic field over NOAA Active Region 11,429 during a X5.4 solar flare on 7 March 2012 is modeled using optimization based Non-Linear Force-Free Field extrapolation. Specifically, 3D magnetic fields were modeled for 11 timesteps using the 12-min cadence Solar Dynamics Observatory (SDO) Helioseismic and Magnetic Imager photospheric vector magnetic field data, spanning a time period of 1 hour before through 1 hour after the start of the flare. Using the modeled coronal magnetic field data, seven different magnetic field parameters were calculated for 3 separate regions: areas with surface |Bz| ≥ 300 G, areas of flare brightening seen …


Clumpy Wind Studies And The Nondetection Of A Cyclotron Line In Oao 1657–415, Pragati Pradhan, Carlo Ferrigno, Biswajit Paul, Enrico Bozzo, Ileyk El Mellah, David P. Huenemoerder, James F. Steiner, Victoria Grinberg, Felix Furst, Chandreyee Maitra, Patrizia Romano, Peter Kretschmar, Jamie Kennea, Deepto Chakrabarty 2023 Embry-Riddle Aeronautical University

Clumpy Wind Studies And The Nondetection Of A Cyclotron Line In Oao 1657–415, Pragati Pradhan, Carlo Ferrigno, Biswajit Paul, Enrico Bozzo, Ileyk El Mellah, David P. Huenemoerder, James F. Steiner, Victoria Grinberg, Felix Furst, Chandreyee Maitra, Patrizia Romano, Peter Kretschmar, Jamie Kennea, Deepto Chakrabarty

Publications

Winds of massive stars are suspected to be inhomogeneous (or clumpy), which biases the measures of their mass-loss rates. In high-mass X-ray binaries (HMXBs), the compact object can be used as an orbiting X-ray point source to probe the wind and constrain its clumpiness. We perform a spectrotiming analysis of the HMXB OAO 1657–415 with nonsimultaneous NuSTAR and NICER observations. We compute the hardness ratio from the energy-resolved light curves, and, using an adaptive rebinning technique, we thus select appropriate time segments to search for rapid spectral variations on timescales of a few hundred to thousands of seconds. The column …


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