Astrophysics Research
First Ab Initio DDT Mechanism Explains Why Type Ia Supernovae Are Standard Candles
This paper presents the first globally self-consistent, laboratory-validated mechanism for the deflagration-to-detonation transition (tDDT) in near-Chandrasekhar mass white dwarf Type Ia supernova progenitors, replacing decades of ad hoc detonation-initiation assumptions. Using 3D hydrodynamical sim…
X-ray Pulse Profile Modeling of a 448-Hz Accreting Millisecond Pulsar Yields Large Neutron Star Mass-Radius Constraints via NICER+IXPE Polarimetry
Combined NICER and IXPE observations of the newly discovered accreting millisecond pulsar SRGA J144459.2-604207 (spinning at 448 Hz) were analyzed using relativistic ray-tracing pulse profile modeling to constrain neutron star mass and radius. The best-fit model features two independent, geometrical…
IceCube Releases 14-Year Muon Track Dataset (IceTracks-DR2) for Open Neutrino Source Searches
The IceCube Collaboration has published IceTracks-DR2, its most comprehensive public muon track dataset to date, spanning 14 years of observations (2008–2022) and superseding the prior 10-year release. The dataset incorporates improved detector calibration for post-2010 data and includes binned inst…
EHT Brightness Asymmetry Data Marginally Rules Out Near-Zero Spin for M87*
Using three epochs of Event Horizon Telescope (EHT) observations, the EHT Collaboration compares the observed distribution of ring brightness asymmetry amplitudes in M87* against GRMHD simulation libraries spanning a range of black hole spins. For strongly magnetized (MAD) accretion models, the data…
Sgr A* Polarization Variability During 2018 EHT Campaign Challenges Standard Flare Models
ALMA full-polarization observations of Sagittarius A* during the 2018 EHT campaign reveal a striking asymmetry: total intensity variability is low (<10%), while linear and circular polarization variability reach ~30% and ~50%, respectively — implying polarized emission originates from a spatially an…
Sub-Solar Mass GW Candidate S251112cm: No Kilonova Found, But a Second Coincident Type IIb Supernova Hints at Superkilonova Formation Channel
The LVK collaboration's sub-solar mass gravitational wave candidate S251112cm triggered a rapid multi-facility EM follow-up campaign (DECam, ZTF, FTW) covering 56% of the localization region within 2.4 hours, yielding no kilonova counterpart — with FTW alone ruling out 92% of kilonova models. Howeve…
1:10 Satellite Encounters Produce Universal Dark Matter Halo Deformations: Evidence from the LMC-SMC System
Using basis function expansions applied to a high-resolution N-body simulation of the LMC-SMC system in isolation, this study quantifies the mutual dark matter halo distortions of the Magellanic Clouds prior to Milky Way infall. The SMC induces a ~20 kpc dynamical friction wake and dual overdensitie…
JWST Confirms Metal-Free HeII Emitter Near GN-z11 at z=10.6 — Strongest Evidence Yet for Population III Stars
Using JWST NIRSpec-IFU high-resolution spectroscopy, Maiolino et al. confirm a HeII λ1640 emitter at z=10.6, located just 3 physical kpc from the well-known galaxy GN-z11. The source shows no detectable metal lines and an exceptionally high HeII equivalent width (>20 Å), with the emission spectrally…