Kavli Affiliate: Hitoshi Murayama | Summary:Gravitational radiation from the early Universe offers a powerful window into physics beyond the Standard Model (SM). In this paper, we investigate the low-frequency tail of gravitational radiation produced by the decay of massive particles. The energy spectrum in Minkowski space-time, $dE/dω$, exhibits two distinct regimes: a flat bremsstrahlung/memory spectrum […]
Kavli Affiliate: Frank Wilczek | Summary:The usual WKB analysis for quantum tunneling applies when the tunneling action is large, as it is for tall, wide potential barriers. In contrast we analyze tunneling when the action is small, as it is for tunneling across a tall, thin barrier. We develop a perturbative analysis where the control […]
Kavli Affiliate: Frank Wilczek | Summary:The usual WKB analysis for quantum tunneling applies when the tunneling action is large, as it is for tall, wide potential barriers. In contrast we analyze tunneling when the action is small, as it is for tunneling across a tall, thin barrier. We develop a perturbative analysis where the control […]
Kavli Affiliate: Laura Schaefer | Summary:Recent JWST observations challenge the traditional ‘cosmic shoreline’ from both sides, revealing thick volatile atmospheres on the hottest close-in ‘lava worlds,’ where irradiation should drive the most extreme escape, and bare rocky surfaces on cooler terrestrial planets around M dwarfs, where atmospheres would be expected to survive. Using a coupled […]
Kavli Affiliate: Robert Simcoe | Summary:We investigate the distribution and kinematics of cool circumgalactic medium (CGM) gas across the star-forming to quiescent transition using MgII absorption for 716 galaxies spanning $0.07<z<2.7$ (169 new and 547 archival galaxies). To compare galaxies uniformly across 10 billion years of cosmic time, we introduce a star-formation offset metric ($σ_mathrmSFO$), […]
Kavli Affiliate: Gregory Herczeg | Summary:Multiwavelength observations of stellar flares trace the activity of different components of the stars’ outer atmosphere, providing insight into their interactions. In the present paper, we report a superflare from BP Tau, simultaneously observed with the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) satellite and TESS. While […]
Kavli Affiliate: Michael Turner | Summary:In 1980, the Universe was made of stars, cosmology was the province of less than 100 astronomers, the Hubble constant was only known to within a factor of two, and the hot big bang was the “the standard model of cosmology.” Particle physics was a thriving enterprise concerned with the […]
Kavli Affiliate: Kiyoshi Masui | Summary:We have discovered PSR J2108+5055, an extremely luminous but sporadic mode-changing rotating radio transient (RRAT), with a period of 0.495 s using the Canadian Hydrogen Intensity Mapping Experiment/Fast Radio Burst instrument (CHIME/FRB). We show that the brightest pulse from PSR J2108+5055 has a flux density of 3.1+/-1.0 kJy, corresponding to […]
Kavli Affiliate: Daniel Holz | Summary:Binary population synthesis (BPS) codes are extremely useful tools for investigating both the end-to-end lives of binary stars as well as a myriad of astrophysical phenomena observed in the Universe. Given the widespread use of BPS in modern astrophysical research, it is imperative to systematically compare BPS codes across the […]
Kavli Affiliate: Daniel Holz | Summary:Binary population synthesis (BPS) codes are valuable tools for investigating the end-to-end lives of binary stars as well as a myriad of observed astrophysical phenomena. Many “rapid" BPS codes rely on semi-analytical single-star evolutionary tracks and disjointed prescriptions for binary physics. Updated “hybrid" or “detailed" BPS codes incorporate improved methodologies, […]