209 citations · 2.5k across the 85 of their papers we have counts for
22 papers · 1 filter
SPIRITS 19q: Dust Production by a Subsolar-metallicity Carbon-rich Wolf-Rayet Star in NGC 2403
Sam Rose, Ryan M. Lau, Jacob E. Jencson +20
We present JWST/NIRSpec IFU observations of SPIRITS 19q, the highly dust-producing carbon-rich (WC) binary candidate located in a subsolar-metallicity region of the nearby spiral g…
Fading into darkness: A weak mass ejection and low-efficiency fallback accompanying black hole formation in M31-2014-DS1
Kishalay De, Morgan MacLeod, Jacob E. Jencson +10
Stellar-mass black holes (BHs) can form from the near-complete collapse of massive stars, causing them to abruptly disappear. The star M31-2014-DS1 in the Andromeda galaxy was repo…
SPHEREx as a frontier for infrared transients: Classification of new Galactic FU Ori outbursts and classical novae
Viraj Karambelkar, Kishalay De, Lynne A. Hillenbrand +3
We demonstrate proof-of-concept of a new strategy for studying infrared (IR) transients enabled by the newly launched SPHEREx space mission, by leveraging its synergy with the NEOW…
The nature of ASASSN-24fw's occultation: modelling the event as dimming by optically thick rings around a sub-stellar companion
Sarang Shah, Jonathan P. Marshall, Carlos del Burgo +12
ASASSN-24fw is a main-sequence F-type star that experienced a rapid and long-lasting dimming event beginning in late 2024 and continuing until mid 2025. Its pre-dimming spectral en…
A spectral library and census of near-infrared stellar large-amplitude variables from Palomar Gattini-IR
Nicholas Earley, Viraj Karambelkar, Mansi Kasliwal +9
We present a near-infrared census of stellar large-amplitude variables (LAVs) observed by the Palomar Gattini-IR (PGIR) surveyor from 2019-2021. Over the three-year time period, PG…
Multi-color characterization of optically invisible FU Orionis-type outbursts: Demonstration and prospects for the WINTER survey
Danielle Frostig, Kishalay De, Lynne A. Hillenbrand +8
Episodic mass accretion is the dominant mechanism for mass assembly in the proto-stellar phase. Although prior optical time-domain searches have allowed detailed studies of individ…
Hot springs and dust reservoirs: JWST reveals the dusty, molecular aftermath of extragalactic stellar mergers
Viraj Karambelkar, Mansi Kasliwal, Ryan M. Lau +7
We present James Webb Space Telescope (JWST) observations of four Luminous Red Novae (LRNe): dusty, extragalactic transients from stellar mergers following common-envelope evolutio…
A half-ring of ionized circumstellar material trapped in the magnetosphere of a white dwarf merger remnant
Andrei A. Cristea, Ilaria Caiazzo, Tim Cunningham +31
Many white dwarfs are observed in compact double white dwarf binaries and, through the emission of gravitational waves, a large fraction are destined to merge. The merger remnants…
The slow brightening of WNTR23bzdiq / WTP19aalzlk : Possible onset of common-envelope evolution in an asymptotic giant branch star?
Viraj Karambelkar, Mansi Kasliwal, Kishalay De +6
We present WNTR23bzdiq/WTP19aalzlk, a slow eruption of an early-asymptotic giant branch (AGB) star in M31 identified by the Wide-field Infrared Transient Explorer (WINTER) near-inf…
Oxygen Isotope Ratios in Hydrogen-Deficient Carbon Stars: A Correlation with Effective Temperature and Implications for White Dwarf Merger Outcomes
Advait Mehla, Mansi M. Kasliwal, Viraj Karambelkar +5
Hydrogen-deficient Carbon (HdC) stars are a class of supergiants with anomalous chemical compositions, suggesting that they are remnants of CO-He white dwarf (WD) mergers. This cla…
Hertzsprung gap stars in nearby galaxies and the Quest for Luminous Red Novae Progenitors
Hugo Tranin, Nadejda Blagorodnova, Viraj Karambelkar +5
After the main sequence phase, stars more massive than 2.5 M rapidly evolve through the Hertzsprung gap as yellow giants and supergiants (YSG), before settling into the red…
An infrared census of R Coronae Borealis Stars II -- Spectroscopic classifications and implications for the rate of low-mass white dwarf mergers
Viraj R. Karambelkar, Mansi M. Kasliwal, Patrick Tisserand +18
We present results from a systematic infrared (IR) census of R Coronae Borealis (RCB) stars in the Milky Way, using data from the Palomar Gattini IR (PGIR) survey. R Coronae Boreal…
An Automated Catalog of Long Period Variables using Infrared Lightcurves from Palomar Gattini-IR
Aswin Suresh, Viraj Karambelkar, Mansi M. Kasliwal +8
Stars in the Asymptotic Giant Branch (AGB) phase, dominated by low to intermediate-mass stars in the late stage of evolution, undergo periodic pulsations, with periods of several h…
The 2022-2023 accretion outburst of the young star V1741 Sgr
Michael A. Kuhn, Lynne A. Hillenbrand, Michael S. Connelley +12
V1741 Sgr (= SPICY 71482/Gaia22dtk) is a Classical T Tauri star on the outskirts of the Lagoon Nebula. After at least a decade of stability, in mid-2022, the optical source brighte…
A Luminous Red Supergiant and Dusty Long-period Variable Progenitor for SN 2023ixf
Jacob E. Jencson, Jeniveve Pearson, Emma R. Beasor +23
We analyze pre-explosion near- and mid-infrared (IR) imaging of the site of SN 2023ixf in the nearby spiral galaxy M101 and characterize the candidate progenitor star. The star dis…
R Coronae Borealis and dustless Hydrogen-deficient Carbon stars have different oxygen isotope ratios
Viraj Karambelkar, Mansi Kasliwal, Patrick Tisserand +5
R Coronae Borealis (RCB) and dustless Hydrogen-deficient Carbon (dLHdC) stars are believed to be remnants of low mass white dwarf mergers. These supergiant stars have peculiar hydr…
The dawn of a new era for dustless HdC stars with GAIA eDR3
P. Tisserand, C. L. Crawford, G. C. Clayton +7
Decades after their discovery, only four hydrogen-deficient carbon (HdC) stars were known to have no circumstellar dust shell. This is in complete contrast to the 130 known G…
Outbursting Young Stellar Object PGIR 20dci in the Perseus Arm
Lynne A. Hillenbrand, Kishalay De, Matthew Hankins +9
We report the discovery of a likely outbursting Class I young stellar object, associated with the star-forming region NGC 281-W (distance kpc). The source is currently s…
AT 2019qyl in NGC 300: Internal Collisions in the Early Outflow from a Very Fast Nova in a Symbiotic Binary
Jacob E. Jencson, Jennifer E. Andrews, Howard E. Bond +39
Nova eruptions, thermonuclear explosions on the surfaces of white dwarfs (WDs), are now recognized to be among the most common shock-powered astrophysical transients. We present th…
Census of R Coronae Borealis stars I: Infrared light curves from Palomar Gattini IR
Viraj R. Karambelkar, Mansi M. Kasliwal, Patrick Tisserand +16
We are undertaking the first systematic infrared (IR) census of R Coronae Borealis (RCB) stars in the Milky Way, beginning with IR light curves from the Palomar Gattini IR (PGIR) s…
Progenitor, Precursor and Evolution of the Dusty Remnant of the Stellar Merger M31-LRN-2015
Nadejda Blagorodnova, Viraj Karambelkar, Scott M. Adams +12
M31-2015-LRN is a likely stellar merger discovered in the Andromeda Galaxy in 2015. We present new optical to mid-infrared photometry and optical spectroscopy for this event. Archi…
SPIRITS Catalog of Infrared Variables: Identification of Extremely Luminous Long Period Variables
V. R. Karambelkar, S. M. Adams, P. A. Whitelock +11
We present a catalog of 417 luminous infrared variable stars with periods exceeding 250 days. These were identified in 20 nearby galaxies by the ongoing SPIRITS survey with the Spi…