Jennifer E. Andrews
A5035367076- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Pulsars and Gravitational Waves Research
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Radiation Detection and Scintillator Technologies
- Scientific Computing and Data Management
- Geophysics and Gravity Measurements
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Spectroscopy Techniques in Biomedical and Chemical Research
- Neutrino Physics Research
- Atmospheric Ozone and Climate
- Spectroscopy and Chemometric Analyses
- Superconducting Materials and Applications
- Spacecraft and Cryogenic Technologies
- Planetary Science and Exploration
- Particle Detector Development and Performance
- Methane Hydrates and Related Phenomena
Gemini North Observatory
2021-2025
University of Arizona
2015-2024
Vanderbilt University Medical Center
2022-2024
Gemini South Observatory
2023-2024
NSF’s NOIRLab
2024
NIU Observatory
2023
Hospital Clínic de Barcelona
2020
University of Massachusetts Amherst
2012-2017
Louisiana State University
2009-2012
Louisiana State University Agricultural Center
2011
Double detonations in double white dwarf (WD) binaries undergoing unstable mass transfer have emerged recent years as one of the most promising Type Ia supernova (SN Ia) progenitor scenarios. One potential outcome this "dynamically driven double-degenerate double-detonation" (D^6) scenario is that companion WD survives explosion and flung away with a velocity equal to its > 1000 km/s pre-SN orbital velocity. We perform search for these hypervelocity runaway WDs using Gaia's second data...
The Legacy ExtraGalactic UV Survey (LEGUS) is a Cycle 21 Treasury program on the Hubble Space Telescope aimed at investigation of star formation and its relation with galactic environment in nearby galaxies, from scales individual stars to those ∼kiloparsec-size clustered structures. Five-band imaging near-ultraviolet I band Wide-Field Camera 3 (WFC3), plus parallel optical Advanced for Surveys (ACS), being collected selected pointings 50 galaxies within local 12 Mpc. filters used...
Abstract We present a comprehensive optical and near-infrared census of the fields 90 short gamma-ray bursts (GRBs) discovered in 2005–2021, constituting all GRBs for which host galaxy associations are feasible (≈60% total Swift GRB population). contribute 274 new multi-band imaging observations across 58 distinct 26 spectra their galaxies. Supplemented by literature archival survey data, catalog contains 542 photometric 42 spectroscopic data sets. The reaches 3 σ depths ≳24–27 mag ≳23–26...
Abstract We present the optical spectroscopic evolution of SN 2023ixf seen in subnight cadence spectra from 1.18 to 15 days after explosion. identify high-ionization emission features, signatures interaction with material surrounding progenitor star, that fade over first 7 days, rapid between observed within same night. compare lines and their relative strength those other supernovae early interaction, finding a close match 2020pni 2017ahn spectrum 2014G at later epochs. To physically...
We analyze pre-explosion near- and mid-infrared (IR) imaging of the site SN 2023ixf in nearby spiral galaxy M101 characterize candidate progenitor star. The star displays compelling evidence variability with a possible period $\approx$1000 days an amplitude $\Delta m \approx 0.6$ mag extensive monitoring Spitzer Space Telescope since 2004, likely indicative radial pulsations. Variability consistent this is also seen near-IR $J$ $K_{s}$ bands between 2010 2023, up to just 10 before explosion....
Abstract We present the densely sampled early light curve of Type II supernova (SN) 2023ixf, first observed within hours explosion in nearby Pinwheel Galaxy (Messier 101; 6.7 Mpc). Comparing these data to recently updated models shock-cooling emission, we find that progenitor likely had a radius 410 ± 10 R ⊙ . Our estimate is model dependent but consistent with red supergiant. These provide good fit starting about 1 day after explosion, despite fact classification spectrum shows signatures...
Abstract We follow our first paper with an analysis of the ensemble extensive preexplosion ground- and space-based infrared observations red supergiant (RSG) progenitor candidate for nearby core-collapse supernova SN 2023ixf in Messier 101, together optical data prior to explosion obtained Hubble Space Telescope (HST). have confirmed association (SN), as well constrained metallicity at site, based on instruments Gemini-North. The internal host extinction has also been from a high-resolution...
The supernova (SN) PTF11iqb was initially classified as a Type IIn event caught very early after explosion. It showed narrow Wolf–Rayet (WR) spectral features on day 2 (as in SN 1998S and 2013cu), but the emission weakened quickly spectrum morphed to resemble Types II-L II-P. At late times, Hα exhibited complex, multipeaked profile reminiscent of 1998S. In terms spectroscopic evolution, we find that near twin 1998S, although with somewhat weaker interaction circumstellar material (CSM) at...
We report the large effort which is producing comprehensive high-level young star cluster (YSC) catalogues for a significant fraction of galaxies observed with Legacy ExtraGalactic UV Survey (LEGUS) Hubble treasury program. present methodology developed to extract positions, verify their genuine nature, produce multiband photometry (from NUV NIR), and derive physical properties via spectral energy distribution fitting analyses. use nearby spiral galaxy NGC628 as test case demonstrating...
Abstract Observational evidence points to a red supergiant (RSG) progenitor for SN 2023ixf. The candidate has been detected in archival images at wavelengths (≥0.6 μ m) where RSGs typically emit profusely. This object is distinctly variable the infrared (IR). We characterize variability using pre-explosion mid-IR (3.6 and 4.5 Spitzer ground-based near-IR ( JHK s ) data jointly covering 19 yr. IR light curves exhibit significant with rms amplitudes range 0.2–0.4 mag, increasing decreasing...
Abstract We present JWST near-infrared (NIR) and mid-infrared (MIR) spectroscopic observations of the nearby normal Type Ia supernova (SN) SN 2021aefx in nebular phase at +255 days past maximum light. Our Near Infrared Spectrograph (NIRSpec) Mid Instrument observations, combined with ground-based optical data from South African Large Telescope, constitute first complete optical+NIR+MIR spectrum covering 0.3–14 μ m. This unveils previously unobserved 2.5−5 m region, revealing strong iron...
Abstract We perform a comprehensive search for optical precursor emission at the position of SN 2023ixf using data from DLT40, ZTF, and ATLAS surveys. By comparing current set with outburst hydrodynamical model light curves, we find that probability significant within 5 yr explosion is low, circumstellar material (CSM) ejected during any possible likely smaller than ∼0.015 M ⊙ . to toy models, that, if there was outburst, duration must have been shorter ∼100 days typical brightness r ≃ −9...
Abstract Objective To develop and evaluate a data-driven process to generate suggestions for improving alert criteria using explainable artificial intelligence (XAI) approaches. Methods We extracted data on alerts generated from January 1, 2019 December 31, 2020, at Vanderbilt University Medical Center. developed machine learning models predict user responses alerts. applied XAI techniques global explanations local explanations. evaluated the by comparing with alert’s historical change logs...
Abstract We present high-cadence photometric and spectroscopic observations of supernova (SN) 2024ggi, a Type II SN with flash spectroscopy features, which exploded in the nearby galaxy NGC 3621 at ∼7 Mpc. The light-curve evolution over first 30 hr can be fit by two power-law indices break after 22 hr, rising from M V ≈ −12.95 mag +0.66 day to −17.91 7 days. In addition, densely sampled color curve shows strong blueward few days then behaves as normal redward ejecta cool. Such deviations...
Abstract We present multi-epoch optical spectropolarimetric and imaging polarimetric observations of the nearby Type II supernova (SN) 2023ixf discovered in M101 at a distance 6.85 Mpc. The first were taken +2.33 days (60085.08 MJD) after explosion, while last data points (+73.19 +76.19 days) acquired fall from light-curve plateau. At there is strong evidence circumstellar material (CSM) interaction spectra light curve. A significant level intrinsic polarization p r = 1.02% ± 0.07% seen...
SN 2007od exhibits characteristics that have rarely been seen in a Type IIP supernova (SN). Optical V band photometry reveals very steep brightness decline between the plateau and nebular phases of ~4.5 mag, likely due to containing low mass 56Ni. The optical spectra show an evolution from normal with broad Halpha emission, complex, four component emission profile exhibiting asymmetries caused by dust extinction after day 232. This is similar spectral IIn 1998S, although no early-time narrow...
The Galactic transient V1309 Sco was the result of a merger in low-mass star system, while V838 Mon thought to be similar event from more massive B-type progenitor. In this paper we study an optical/IR discovered nearby galaxy NGC4490, which appeared these events (unobscured progenitor, irregular multi-peaked light curve, increasingly red color, optical spectrum, IR excess at late times), but had higher peak luminosity and longer duration outburst. NGC4490-OT has less common with class...
We present a moderate-resolution spectrum of the peculiar Type II supernova iPTF14hls taken on day 1153 after discovery. This reveals clear signature shock interaction with dense circumstellar material (CSM). suggest that this CSM may be an important clue for understanding extremely unusual photometric and spectroscopic evolution seen over first 600 days iPTF14hls. The late-time shows double-peaked intermediate-width H-alpha line indicative expansion speeds around 1000 km/s, shape hinting at...
We have identified a progenitor candidate in archival Hubble Space Telescope (HST) images for the Type Ic SN 2017ein NGC 3938, pinpointing candidate's location via HST Target-of-Opportunity imaging of itself. This would be first identification stellar-like object as any supernova to date. also present observations during ~49 days since explosion. find that most resembles well-studied 2007gr. infer experienced total visual extinction A_V~1.0--1.9 mag, predominantly because dust within host...
Supernova (SN) 2005ip was a Type IIn event notable for its sustained strong interaction with circumstellar material (CSM), coronal emission lines and infrared (IR) excess, interpreted as shock the very dense clumpy wind of an extreme red supergiant. We present series late-time spectra SN first radio detection this SN, plus X-rays, all which indicate that CSM is still decade post-explosion. also discuss new geriatric SNe continued interaction: 1988Z, 1993J 1998S. From 3 to 10 yr...
Abstract We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in star-forming galaxy M100 ( d ≈ 16.2 Mpc) starting 10 hr after explosion continuing for ∼300 days. SN shows a double-peaked optical light curve peaking at t = 3 15 The first peak is coincident with luminous, rapidly decaying Swift-XRT–discovered X-ray emission <?CDATA ${L}_{{\rm{x}}}\approx {10}^{41}\,\mathrm{erg}\,{{\rm{s}}}^{-1}$?> days; L x ∝ −3 ), Shane/Kast spectral detection narrow H...
We present new HST imaging photometry for the site of Type IIn supernova (SN) 2009ip taken almost a decade after explosion. The optical source has continued to fade steadily since SN-like event in 2012. In F606W filter, which was also used detect its luminous blue variable (LBV) progenitor 13~yr before SN, at position SN2009ip is now 1.2mag fainter than that quiescent progenitor. It 6-7mag pre-SN outbursts 2009--2011. This definitively rules out prediction would return previous state...
Abstract We present a JWST/MIRI low-resolution mid-infrared (MIR) spectroscopic observation of the normal Type Ia supernova (SN Ia) SN 2021aefx at +323 days past rest-frame B -band maximum light. The spectrum ranges from 4 to 14 μ m and shows many unique qualities, including flat-topped [Ar iii ] 8.991 profile, strongly tilted [Co 11.888 feature, multiple stable Ni lines. These features provide critical information about physics explosion. observations are compared synthetic spectra detailed...
We present photometric and spectroscopic observations of the extraordinary gamma-ray burst (GRB) 221009A in search an associated supernova. Some past GRBs have shown bumps optical light curve that coincide with emergence supernova spectral features, but we do not detect any significant features GRB~221009A, nor clear sign features. Using two well-studied GRB-associated supernovae (SN~2013dx, $M_{r,max} = -19.54$; SN~2016jca, -19.04$) at a similar redshift as GRB~221009A ($z=0.151$), modeled...