papers

Publications (27)

physics.flu-dyn2023

Flow characterisation and power consumption in an inline high shear rotor-stator mixer using CFD

Vipin Michael, Umair Ahmed, Mahmoud Assad +2

The aim of this paper is two-fold: (1) to provide a detailed investigation of the turbulent flow in an inline high-shear rotor stator mixer; (2) to provide a comparison of two diff…

astro-ph.SR2020

Coronal Dimming as a Proxy for Stellar Coronal Mass Ejections

Meng Jin, Mark C. M. Cheung, Marc L. DeRosa +6

Solar coronal dimmings have been observed extensively in the past two decades and are believed to have close association with coronal mass ejections (CMEs). Recent study found that…

astro-ph.IM2019

STROBE-X: X-ray Timing and Spectroscopy on Dynamical Timescales from Microseconds to Years

Paul S. Ray, Zaven Arzoumanian, David Ballantyne +155

We present the Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X), a probe-class mission concept selected for study by NASA. It combines huge collectin…

astro-ph.SR2023

Can Proton Beam Heating Flare Models Explain Sunquakes?

Viacheslav Sadykov, John Stefan, Alexander Kosovichev +4

SDO/HMI observations reveal a class of solar flares with substantial energy and momentum impacts in the photosphere, concurrent with white-light emission and helioseismic responses…

astro-ph.SR2025

Discovery of multi-temperature coronal mass ejection signatures from a young solar analogue

Kosuke Namekata, Kevin France, Jongchul Chae +14

Coronal mass ejections (CMEs) on the early Sun may have profoundly influenced the planetary atmospheres of early Solar System planets. Flaring young solar analogues serve as excell…

astro-ph.IM2022

Development of Integral Field Spectrographs to Revolutionize Spectroscopic Observations of Solar Flares and other Energetic Solar Eruptions

Haosheng Lin, Tetsu Anan, Gianna Cauzzi +9

The Sun's proximity offers us a unique opportunity to study in detail the physical processes on a star's surface; however, the highly dynamic nature of the stellar surface -- in pa…

astro-ph.EP2019

EUV influences on exoplanet atmospheric stability and evolution

Allison Youngblood, Kevin France, Tommi Koskinen +15

The planetary effective surface temperature alone is insufficient to characterize exoplanet atmospheres and their stability or evolution. Considering the star-planet system as a wh…

physics.flu-dyn2025

Predicting the distribution of yield-stress fluids in branched pipe manifolds

Elliott Sutton, Waldo Rosales Trujillo, Adam Kowalski +2

We develop a one-dimensional network model to predict the steady-state distribution of yield-stress fluids in branched pipe manifolds under wall-slip conditions. The model accounts…

astro-ph.EP2024

TOI-2015b: A Warm Neptune with Transit Timing Variations Orbiting an Active mid M Dwarf

Sinclaire E. Jones, Gudmundur Stefansson, Kento Masuda +29

We report the discovery of a close-in () warm Neptune with clear transit timing variations (TTVs) orbiting the nearby ($d=47.3\:\mathrm{pc}…

astro-ph.SR2024

Evolution of Flare Activity in GKM Stars Younger than 300 Myr over Five Years of TESS Observations

Adina D. Feinstein, Darryl Z. Seligman, Kevin France +2

Stellar flares are short-duration ( hours) bursts of radiation associated with surface magnetic reconnection events. Stellar magnetic activity generally decreases as a function…

astro-ph.SR2019

EUV observations of cool dwarf stars

Allison Youngblood, Jeremy Drake, James Mason +15

The EUV (100-912 Ã ) is a spectral region notoriously difficult to observe due to attenuation by neutral hydrogen gas in the interstellar medium. Despite this, hundreds to thousand…

astro-ph.SR2026

Spectroscopic analysis and RHD modeling of the first Ca II H and H-epsilon flare spectra from DKIST/ViSP

Cole Tamburri, Adam Kowalski, Gianna Cauzzi +7

We analyze decay phase observations of the GOES class C6.7 flare SOL2022-08-19T20:31 by the Visible Spectropolarimeter (ViSP) on the National Science Foundation's Daniel K. Inouye…

physics.flu-dyn2023

A comparison between the FENE-P and sPTT constitutive models in Large Amplitude Oscillatory Shear (LAOS)

Thomas P John, Robert J Poole, Adam Kowalski +1

The FENE-P and sPTT viscoelastic models are widely used for modelling of complex fluids. Although they are derived from distinct micro-structural theories, these models can become…

astro-ph.SR2017

Exploring impulsive solar magnetic energy release and particle acceleration with focused hard X-ray imaging spectroscopy

Steven Christe, Samuel Krucker, Lindsay Glesener +37

How impulsive magnetic energy release leads to solar eruptions and how those eruptions are energized and evolve are vital unsolved problems in Heliophysics. The standard model for…

astro-ph.IM2009

LSST Science Book, Version 2.0

LSST Science Collaboration, Paul A. Abell, Julius Allison +245

A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade.…

cs.LG2024

Integrating knowledge-guided symbolic regression and model-based design of experiments to automate process flow diagram development

Alexander W. Rogers, Amanda Lane, Cesar Mendoza +4

New products must be formulated rapidly to succeed in the global formulated product market; however, key product indicators (KPIs) can be complex, poorly understood functions of th…

astro-ph.EP2023

NEID Reveals that The Young Warm Neptune TOI-2076 b Has a Low Obliquity

Robert C. Frazier, Gudmundur Stefansson, Suvrath Mahadevan +27

TOI-2076 b is a sub-Neptune-sized planet () that transits a young () bright () K-dwarf hosting a system of three transiting…

astro-ph.SR2023

The F-CHROMA grid of 1D RADYN flare models

Mats Carlsson, Lyndsay Fletcher, Joel Allred +6

Context: Solar flares are the result of the sudden release of magnetic energy in the corona. Much of this energy goes into accelerating charged particles to high velocity. These pa…

astro-ph.EP2021

Non-detection of Helium in the upper atmospheres of TRAPPIST-1b, e and f

Vigneshwaran Krishnamurthy, Teruyuki Hirano, Guðmundur Stefánsson +37

We obtained high-resolution spectra of the ultra-cool M-dwarf TRAPPIST-1 during the transit of its planet `b' using two high dispersion near-infrared spectrographs, IRD instrument…

astro-ph.SR2021

The Mega-MUSCLES Spectral Energy Distribution Of TRAPPIST-1

David J. Wilson, Cynthia S. Froning, Girish M. Duvvuri +19

We present a 5A-100um Spectral Energy Distribution (SED) of the ultracool dwarf star TRAPPIST-1, obtained as part of the Mega-MUSCLES Treasury Survey. The SED combines ultraviolet…

astro-ph.SR2026

Enigmatic Line Broadening During Solar Flares: Magnetic Field Broadening?

Thomas Gomez, Adam Kowalski, Cole Tamburri +2

The origin of the extreme broadening observed in chromospheric metal lines during solar and stellar flares, particularly Mg II h&k and Ca II H&K, remains poorly understood. These l…

astro-ph.SR2017

The MUSCLES Treasury Survey IV: Scaling Relations for Ultraviolet, Ca II K, and Energetic Particle Fluxes from M Dwarfs

Allison Youngblood, Kevin France, R. O. Parke Loyd +18

Characterizing the UV spectral energy distribution (SED) of an exoplanet host star is critically important for assessing its planet's potential habitability, particularly for M dwa…

astro-ph.SR2020

Spectral signatures of chromospheric condensation in a major solar flare

David R. Graham, Gianna Cauzzi, Luca Zangrilli +3

We study the evolution of chromospheric line and continuum emission during the impulsive phase of the X-class SOL2014-09-10T17:45 solar flare. We extend previous analyses of this f…

astro-ph.IM2023

The Focusing Optics X-ray Solar Imager (FOXSI)

Steven Christe, Meriem Alaoui, Joel Allred +26

FOXSI is a direct-imaging, hard X-ray (HXR) telescope optimized for solar flare observations. It detects hot plasma and energetic electrons in and near energy release sites in the…

astro-ph.SR2012

DRAFTS: A Deep, Rapid Archival Flare Transient Search in the Galactic Bulge

Rachel A. Osten, Adam Kowalski, Kailash Sahu +1

We utilize the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) HST/ACS dataset for a Deep Rapid Archival Flare Transient Search (DRAFTS) to constrain the flare rate…

astro-ph.SR2016

A Very Bright, Very Hot, and Very Long Flaring Event from the M Dwarf Binary System DG CVn

Rachel A. Osten, Adam Kowalski, Stephen A. Drake +10

On April 23, 2014, the Swift satellite responded to a hard X-ray transient detected by its Burst Alert Telescope, which turned out to be a stellar flare from a nearby, young M dwar…

cond-mat.mtrl-sci2014

Ab initio calculation of anisotropic interfacial excess free energies

Axel van de Walle, Chirranjeevi Balaji Gopal, Steve Demers +5

We describe a simple method to determine, from ab initio calculations, the complete orientation-dependence of interfacial free energies in solid-state crystalline systems. We illus…