Scholarly Work - Physics
Recent Submissions
-
Confident detection of doubly ionized thorium in the extreme Ap star CPD-62° 2717
(Oxford University Press, 2023-05)Despite the Universe containing primordial thorium (Th) of sufficient abundance to appear in stellar spectra, detection of Th has to date been tentative and based on just a few weak and blended lines. Here, we present ... -
The Role of Magnetic Shear in Reconnection-Driven Flare Energy Release
(Cornell University, 2023-08)Using observations from the Solar Dynamics Observatory's Atmosphere Imaging Assembly and the Ramaty High Energy Solar Spectroscopic Imager, we present novel measurements of the shear of post-reconnection flare loops (PRFLs) ... -
Origins of the Evil Eye: M64's Stellar Halo Reveals the Recent Accretion of an SMC-mass Satellite
(American Astronomical Society, 2023-06)M64, often called the "Evil Eye" galaxy, is unique among local galaxies. Beyond its dramatic, dusty nucleus, it also hosts an outer gas disk that counter-rotates relative to its stars. The mass of this outer disk is ... -
JWST’s PEARLS: TN J1338–1942 – I. Extreme jet-triggered star formation in a z = 4.11 luminous radio galaxy
(Oxford University Press, 2023-04)We present the first JWST observations of the z = 4.11 luminous radio galaxy TN J1338–1942, obtained as part of the ‘Prime Extragalactic Areas for Reionization and Lensing Science’ (‘PEARLS’) project. Our NIRCam observations, ... -
Structure of the Plasma near the Heliospheric Current Sheet as Seen by WISPR/Parker Solar Probe from inside the Streamer Belt
(IOP Publising, 2023-05)Parker Solar Probe (PSP) crossed the heliospheric current sheet (HCS) near the perihelion on encounters E8 and E11, enabling the Wide-field Imager for Solar Probe (WISPR) to image the streamer belt plasma in high resolution ... -
The Imprint of Clump Formation at High Redshift. II. The Chemistry of the Bulge
(American Astronomical Society, 2023-04)In Paper I, we showed that clumps in high-redshift galaxies, having a high star formation rate density (ΣSFR), produce disks with two tracks in the [Fe/H]–[α/Fe] chemical space, similar to that of the Milky Way's (MW's) ... -
Ambipolar Heating of Magnetars
(American Astronomical Society, 2023-03)Magnetars, neutron stars thought to be with ultrastrong magnetic fields of 1014–15 G, are observed to be much hotter than ordinary pulsars with ∼1012 G, and additional heating sources are required. One possibility is heating ... -
NuSTAR Observations of a Heavily X-Ray-obscured AGN in the Dwarf Galaxy J144013+024744
(American Astronomical Society, 2023-01)We present a multiwavelength analysis of the dwarf Seyfert 2 galaxy J144013+024744, a candidate obscured active galactic nucleus (AGN) thought to be powered by an intermediate-mass black hole (IMBH, M • ≈ 104−106 M ⊙) of ... -
Multiwavelength scrutiny of X-ray sources in dwarf galaxies: ULXs versus AGNs
(Oxford University Press, 2023-01)Owing to their quiet evolutionary histories, nearby dwarf galaxies (stellar masses M⋆≲3×109M⊙) have the potential to teach us about the mechanism(s) that ‘seeded’ the growth of supermassive black holes, and also how the ... -
Auger electron spectroscopy mapping of lithium niobate ferroelectric domains with nano-scale resolution
(Optica Publishing Group, 2022-12)The +/−Z ferroelectric domains in periodically poled lithium niobate are characterized with Auger electron spectroscopy. The -Z domains have a higher Auger O-KLL transition amplitude than the +Z domains. Based on this, ... -
First Flight of the EUV Snapshot Imaging Spectrograph (ESIS)
(American Astronomical Society, 2022-10)The Extreme-ultraviolet Snapshot Imaging Spectrograph (ESIS) launched on a sounding rocket from White Sands Missile Range on 2019 September 30. ESIS is a computed tomography imaging spectrograph (CTIS) designed to map ... -
Intermediate-mass black holes and the Fundamental Plane of black hole accretion
(Oxford University Press, 2022-09)We present new 5 GHz Very Large Array observations of a sample of eight active intermediate-mass black holes with masses 104.9 M⊙ < M < 106.1 M⊙ found in galaxies with stellar masses M* < 3 × 109 M⊙. We detected five of ... -
Extracting the Heliographic Coordinates of Coronal Rays Using Images from WISPR/Parker Solar Probe
(Springer Science and Business Media LLC, 2022-09)The Wide-field Imager for Solar Probe (WISPR) onboard Parker Solar Probe (PSP), observing in white light, has a fixed angular field of view, extending from 13.5∘ to 108∘ from the Sun and approximately 50∘ in the transverse ... -
Nano-scale ferroelectric domain differentiation in periodically poled lithium niobate with auger electron spectroscopy
(Optica Publishing Group, 2022-03)A new method for characterizing lithium niobate +/-Z ferroelectric polarization domains using Auger electron spectroscopy (AES) is presented. The domains of periodically poled samples are found to be differentiable using ... -
Hundreds of Low-mass Active Galaxies in the Galaxy And Mass Assembly (GAMA) Survey
(American Astronomical Society, 2022-09)We present an entirely new sample of 388 low-mass galaxies (M ⋆ ≤ 1010 M ⊙) that have spectroscopic signatures indicating the presence of massive black holes (BHs) in the form of active galactic nuclei (AGNs) or tidal ... -
Determining the Spectral Content of MOSES Images
(American Astronomical Society, 2022-06)The Multi-Order Solar Extreme Ultraviolet Spectrograph (MOSES) sounding rocket was launched from White Sands Missile Range on 2006 February 8th, to capture images of the Sun in the He ii 303.8 Å emission line. MOSES is a ... -
Wandering Black Hole Candidates in Dwarf Galaxies at VLBI Resolution
(American Astronomical Society, 2022-07)Thirteen dwarf galaxies have recently been found to host radio-selected accreting massive black hole (MBH) candidates, some of which are “wandering” in the outskirts of their hosts. We present 9 GHz Very Long Baseline Array ... -
Fossil turtle eggs from the Upper Cretaceous Gaogou Formation, Xiaguan-Gaoqiu Basin, Neixiang County, Henan Province, China: Interpretation of the transformation from aragonite to calcite in fossil turtle eggshell
(Elsevier BV, 2022-06)In 2007, a clutch of approximately 30 fossil eggs reported from the Upper Cretaceous Gaogou Formation, Xiaguan-Gaoqiu Basin, Neixiang County, Henan Province, China was assigned to the oofamily “Crocodiloolithidae”. After ... -
Environmental Factors Affecting Feather Taphonomy
(MDPI AG, 2022-05)The exceptional preservation of feathers in the fossil record has led to a better understanding of both phylogeny and evolution. Here we address factors that may have contributed to the preservation of feathers in ancient ... -
Thermal transport in two-dimensional nematic superconductors
(American Physical Society, 2022-06)We study the thermal transport in a two-dimensional system with coexisting superconducting (SC) and nematic orders. We analyze the nature of the coexistence phase in a tight-binding square lattice where the nematic state ...