A5042370662- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Spectroscopy and Laser Applications
- Solar and Space Plasma Dynamics
- Pharmacological Effects and Assays
- Geophysics and Gravity Measurements
- Ionosphere and magnetosphere dynamics
- Photocathodes and Microchannel Plates
- Atmospheric and Environmental Gas Dynamics
- Phase Equilibria and Thermodynamics
- CCD and CMOS Imaging Sensors
The Ohio State University
2022-2024
Michigan State University
2019-2023
Pittsburgh Supercomputing Center
2016-2019
University of Pittsburgh
2016-2019
Abstract The structure and chemistry of the dusty interstellar medium (ISM) are shaped by complex processes that depend on local radiation field, gas composition, dust grain properties. Of particular importance polycyclic aromatic hydrocarbons (PAHs), which emit strong vibrational bands in mid-infrared, play a key role ISM energy balance. We recently identified global correlations between PAH band optical line ratios across three nearby galaxies, suggesting connection heating ionization...
We present a high-resolution view of bubbles within The Phantom Galaxy (NGC 628); nearby (~10Mpc), star-forming (~2Msun/yr), face-on (i~9deg) grand-design spiral galaxy. With new data obtained as part the PHANGS-JWST treasury program, we perform detailed case-study two regions interest, one which contains largest and most prominent bubble in galaxy (The Void; over 1kpc diameter), other being smaller region that may be precursor to such large Precursor Void). When comparing matched resolution...
Supernova remnants (SNRs) in Local Group galaxies offer unique insights into the origin of different types supernovae. In order to take full advantage these insights, one must understand intrinsic and environmental diversity SNRs context their host galaxies. We introduce a semi-analytic model that reproduces statistical properties radio continuum-selected SNR population, taking account detection limits surveys, range SN kinetic energies, measured ISM stellar mass distribution galaxy from...
Radiation pressure is a key mechanism by which stellar feedback disrupts molecular clouds and drives HII region expansion. This includes direct radiation exerted UV photons on dust grains, associated with photoionization, infrared (IR) grains due to dust-reprocessed IR photons. We present new method that combines high resolution mid-IR luminosities from JWST-MIRI, optical attenuation nebular line measurements VLT-MUSE, HST H$\alpha$-based sizes estimate the strength of in $\approx 18,000$...
We compare measurements of star formation efficiency to cloud-scale gas properties across PHANGS-ALMA. Dividing 67 galaxies into 1.5 kpc scale regions, we calculate the molecular depletion time, tau_dep= Sigma_mol/Sigma_SFR, and per free-fall eff=tau_ff/tau_dep, for each region. Then test how tau_dep eff vary as functions regional mass-weighted mean on cloud scales (60-150pc): surface density, <Sigma_mol^cloud>, velocity dispersion, <sigma_mol^cloud>, virial parameter, <alpha_vir^cloud>,...
We present Surveying the Whirlpool at Arcseconds with NOEMA (SWAN), a high-resolution, high-sensitivity survey to map molecular lines in 3mm band M51 (the galaxy). SWAN has obtained largest (∼ 5 7,kpc^2) of emission ∼cloud-scale resolution ($3 125,$pc) an external galaxy date. Here, we describe observations and data reduction ∼214,hours interferometric from Northern Extended Millimetre Array (NOEMA) ∼55,hours tailored new 30m telescope Institut de radioastronomie millimétrique (IRAM), as...
Abstract JWST observations, when combined with Hubble Space Telescope (HST) data, promise to improve age estimates of star clusters in nearby spiral galaxies. However, feedback from young cluster stars pushes out the natal gas and dust, making formation evolution a challenge model. Here, we use JWST+ HST observations galaxy NGC 628 produce spectral energy distribution (SED) templates compact spanning 275 nm through 21 μ m. These preliminary SEDs capture associated dust within radii ≈0...
Abstract Radiation pressure is a key mechanism by which stellar feedback disrupts molecular clouds and drives H ii region expansion. This includes direct radiation exerted UV photons on dust grains, associated with photoionization, infrared (IR) grains due to dust-reprocessed IR photons. We present new method that combines high-resolution mid-IR luminosities from JWST-MIRI, optical attenuation, nebular line measurements the Very Large Telecope Multi-Unit Spectroscopic Explorer (VLT-MUSE),...
ABSTRACT Young stellar objects (YSOs) are the gold standard for tracing star formation in galaxies but have been unobservable beyond Milky Way and Magellanic Clouds. But that all changed when JWST was launched, which we use to identify YSOs Local Group galaxy M33, marking first time individual identified at these large distances. We present Mid-Infrared Instrument (MIRI) imaging mosaics 5.6 21 $\mu$m cover a significant portion of one M33’s spiral arms has existing panchromatic from Hubble...
Context. Stellar feedback is a key contributor to the morphology and dynamics of interstellar medium in star-forming galaxies. In particular, energy momentum input from massive stars can drive turbulent motions gas, but dominance efficiency this process are unclear. The study ionised superbubbles enables quantitative constraints be placed on energetics stellar feedback. Aims. We directly compare kinetic expanding with mechanical deposited by form winds supernovae. With such comparison, we...
Abstract High-resolution JWST-MIRI images of nearby spiral galaxies reveal emission with complex substructures that trace dust heated both by massive young stars and the diffuse interstellar radiation field. We present high angular (0.″85) physical resolution (20–80 pc) measurements probability distribution function (PDF) mid-infrared (mid-IR) (7.7–21 μ m) from 19 star-forming PHANGS-JWST Cycle 1 Treasury. The PDFs mid-IR disks all consistently show two distinct components: an approximately...
Abstract We present very early photometric and spectroscopic observations of the Type Ia supernova (SN Ia) 2023bee, starting about 8 hr after explosion, which reveal a strong excess in optical nearest UV ( U UVW1 ) bands during first several days explosion. This data set allows us to probe nature binary companion exploding white dwarf conditions leading its ignition. find good match Kasen model main-sequence star stings ejecta with shock as they buzz past. Models double detonations, shells...
Abstract We present the Physics at High Angular resolution in Nearby GalaxieS (PHANGS)-AstroSat atlas, which contains UV imaging of 31 nearby star-forming galaxies captured by Ultraviolet Imaging Telescope on AstroSat satellite. The atlas provides a homogeneous data set far-UV and near-UV maps within distance 22 Mpc median angular 1.″4 (corresponding to physical scale between 25 160 pc). After subtracting uniform background accounting for Milky Way extinction, we compare our estimated flux...
Abstract We present photometric and spectroscopic observations of the nearby Type Ia SN 2019yvq, from its discovery ∼1 day after explosion to ∼100 days peak brightness. This exhibits several unusual features, most notably an extremely bright UV excess seen within ∼5 explosion. As in Swift data, this early outshines “peak” brightness, making object more extreme than other supernovae (SNe) with UV/blue excesses (e.g., iPTF14atg 2017cbv). In addition, it was underluminous M B = −18.4,...
We have performed a search over 3440 deg$^2$ of Epoch 1 (2017-2019) the Very Large Array Sky Survey to identify unobscured quasars in optical ($0.2 < z 3.2$) and obscured active galactic nuclei (AGN) infrared that brightened dramatically radio past one two decades. These sources would been previously classified as "radio-quiet" based on upper limits from Faint Images Radio at Twenty Centimeters survey (1993-2011), but they are now consistent with "radio-loud" ($L_{\rm 3\,GHz} = 10^{40 - 42}...
We present multiwavelength photometric and spectroscopic observations of SN 2019ein, a high-velocity Type Ia supernova (SN Ia) discovered in the nearby galaxy NGC 5353 with two-day nondetection limit. 2019ein exhibited some highest measured expansion velocities any Ia, Si II absorption minimum blueshifted by 24,000 km s$^{-1}$ at 14 days before peak brightness. More unusually, we observed emission components P Cygni profiles to be upward 10,000 B-band maximum light. This blueshift, among...
Abstract We present deep Chandra X-ray observations of two nearby Type Ia supernovae, SN 2017cbv and 2020nlb, which reveal no emission down to a luminosity L X ≲ 5.3 × 10 37 5.4 erg s −1 (0.3–10 keV), respectively, at ∼16–18 days after the explosion. With these limits, we constrain pre-explosion mass-loss rate progenitor system be <?CDATA $\dot{M}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow>...
ABSTRACT The origin of arcmin-sized odd radio circles (ORCs) found in modern all-sky surveys remains uncertain, with explanations ranging from starburst/active galactic nucleus-driven shocks to supernova remnants (SNRs) the low-density ambient medium. Using well-calibrated light-curve models, we assess possibility that ORCs are SNRs low densities. Our models imply if 1–5 SNRs, they must be within 200–350 kpc Sun, given their observed flux densities and sizes. To evolving circumgalactic...
Although it is well-established that some extragalactic radio sources are time-variable, the properties of this variability, and its connection with host galaxy properties, remain to be explored---particularly for faint sources. Here we present an analysis variable from CHILES Variable Explosive Radio Dynamic Evolution Survey (CHILES VERDES)---a partner project 1.4 GHz COSMOS \ion{H}{1} Large Extragalactic (CHILES). VERDES provides unprecedented combination survey depth, duration, cadence,...
Abstract We measure the molecular gas environment near recent (<100 yr old) supernovae (SNe) using ∼1″ or ≤150 pc resolution CO (2–1) maps from PHANGS–Atacama Large Millimeter/submillimeter Array (ALMA) survey of nearby star-forming galaxies. This is arguably first such study to approach scales individual massive clouds ( M mol ≳ 10 5.3 ⊙ ). Using Open Supernova Catalog, we identify 63 SNe within PHANGS–ALMA footprint. detect emission ∼60% sample at 150 resolution, compared ∼35% map...
Calcium-rich (Ca-rich) transients are a new class of supernovae (SNe) that known for their comparatively rapid evolution, modest peak luminosities, and strong nebular calcium emission lines. Currently, the progenitor systems Ca-rich remain unknown. Although they exhibit spectroscopic properties not unlike core-collapse Type Ib/c SNe, nearly half found in outskirts host galaxies predominantly elliptical, suggesting closer connection to older stellar populations SNe Ia. In this paper, we...
Abstract We present new 0.3–21 μ m photometry of SN 2021aefx in the spiral galaxy NGC 1566 at +357 days after B -band maximum, including first detection any Type Ia supernova (SN Ia) >15 m. These observations follow earlier JWST +255 time maximum brightness, allowing us to probe temporal evolution emission properties. measure fraction flux emerging different wavelengths and its evolution. Additionally, integrated 0.3–14 decay rate Δ = 1.35 ± 0.05 mag/100 is higher than decline from...
Young supernova remnants (SNRs) provide a unique perspective on (SN) progenitors and connect the late evolution of SNe with onset SNR phase. Here we study SN 1885A G1.9+0.3, most recent thermonuclear in Local Group (with ages $\sim 100$ years) radio data, which provides sensitive probe environment energetics. We reduce co-add 4-8 GHz observations from Karl G. Jansky Very Large Array (VLA) to produce deepest image M31 central region (RMS noise 1.3 $\mu$Jy/beam at 6.2 GHz). detect some diffuse...
Abstract We have imaged 35 yr of archival Very Large Array observations the nearby ( d L = 3.15 Mpc) Type Ia supernovae SN 1972E and 1895B between 9 121 post-explosion. No radio emission is detected, constraining their luminosities to be ν ,8.5GHz < 6.0 × 10 23 erg s −1 Hz 45 post-explosion 8.9 post-explosion, respectively. These limits imply a clean circumstellar medium (CSM), with n 0.9 cm −3 out radii few ×10 18 cm, if blast wave expanding into uniform density material. also constrain...
As part of an on-going study radio transients in Epoch 1 (2017-2019) the Very Large Array Sky Survey (VLASS), we have discovered a sample 0.2<z<3.2 active galactic nuclei (AGN) selected optical/infrared that recently brightened dramatically radio. These sources would previously been classified as radio-quiet based on upper limits from Faint Images Radio at Twenty-centimeters (FIRST; 1993-2011) survey; however, they are now consistent with radio-loud quasars. We present quasi-simultaneous,...