Search Publications
JWST's PEARLS: Bright 1.5-2.0 µm Dropouts in the Spitzer/IRAC Dark Field
Grogin, Norman A.; Hathi, Nimish P.; Pirzkal, Nor +35 more
Using the first epoch of four-band NIRCam observations obtained by the James Webb Space Telescope (JWST) Prime Extragalactic Areas for Reionization and Lensing Science Program in the Spitzer IRAC Dark Field, we search for F150W and F200W dropouts. In 14.2 arcmin2, we have found eight F150W dropouts and eight F200W dropouts, all brighter…
A High-resolution Optical Survey of Upper Sco: Evidence for Coevolution of Accretion and Disk Winds
Fang, Min; Pascucci, Ilaria; Edwards, Suzan +3 more
Magnetohydrodynamic (MHD) and photoevaporative winds are thought to play an important role in the evolution and dispersal of planet-forming disks. Here, we analyze high-resolution (Δv ~ 7 km s-1) optical spectra from a sample of 115 T Tauri stars in the ~5-10 Myr Upper Sco association and focus on the [O I] λ6300 and Hα lines to trace d…
A prescription for the asteroseismic surface correction
Li, Yaguang; Huber, Daniel; Bedding, Timothy R. +11 more
In asteroseismology, the surface effect refers to a disparity between the observed and the modelled frequencies in stars with solar-like oscillations. It originates from improper modelling of the surface layers. Correcting the surface effect usually requires using functions with free parameters, which are conventionally fitted to the observed freq…
Cepheid Metallicity in the Leavitt Law (C- MetaLL) survey - II. High-resolution spectroscopy of the most metal poor Galactic Cepheids
Ripepi, V.; Marconi, M.; Musella, I. +5 more
Classical Cepheids (DCEPs) are the first fundamental step in the calibration of the cosmological distance ladder. Furthermore, they represent powerful tracers in the context of Galactic studies. We have collected high-resolution spectroscopy with UVES@VLT for a sample of 65 DCEPs. The majority of them are the faintest DCEPs ever observed in the Mi…
Traveling kink oscillations of coronal loops launched by a solar flare
Tian, Hui; Li, Dong; Ji, Kaifan +5 more
Context. Kink oscillations, which are often associated with magnetohydrodynamic waves, are usually identified as transverse displacement oscillations of loop-like structures. However, the traveling kink oscillation evolving to a standing wave has rarely been reported.
Aims: We investigate the traveling kink oscillation triggered by a solar fl…
PHANGS-JWST First Results: A Global and Moderately Resolved View of Mid-infrared and CO Line Emission from Galaxies at the Start of the JWST Era
Ellison, Sara L.; Wilson, Christine D.; Bolatto, Alberto D. +42 more
We explore the relationship between mid-infrared (mid-IR) and CO rotational line emission from massive star-forming galaxies, which is one of the tightest scalings in the local universe. We assemble a large set of unresolved and moderately (~1 kpc) spatially resolved measurements of CO (1-0) and CO (2-1) intensity, I CO, and mid-IR inte…
Timing the r-process Enrichment of the Ultra-faint Dwarf Galaxy Reticulum II
Brown, Thomas M.; Bacon, D.; Smith, M. +65 more
The ultra-faint dwarf galaxy Reticulum II (Ret II) exhibits a unique chemical evolution history, with ${72}_{-12}^{+10}$ % of its stars strongly enhanced in r-process elements. We present deep Hubble Space Telescope photometry of Ret II and analyze its star formation history. As in other ultra-faint dwarfs, the color-magnitude diagram is best fit …
Resolved imaging confirms a radiation belt around an ultracool dwarf
Kao, Melodie M.; Shkolnik, Evgenya L.; Mioduszewski, Amy J. +1 more
Radiation belts are present in all large-scale Solar System planetary magnetospheres: Earth, Jupiter, Saturn, Uranus and Neptune1. These persistent equatorial zones of relativistic particles up to tens of megaelectron volts in energy can extend further than ten times the planet's radius, emit gradually varying radio emissions2-4
A BayeSN distance ladder: H0 from a consistent modelling of Type Ia supernovae from the optical to the near-infrared
Narayan, Gautham; Jha, Saurabh W.; Dhawan, Suhail +4 more
The local distance ladder estimate of the Hubble constant (H0) is important in cosmology, given the recent tension with the early universe inference. We estimate H0 from the Type Ia supernova (SN Ia) distance ladder, inferring SN Ia distances with the hierarchical Bayesian SED model, BayeSN. This method has a notable advantag…
Updated constraints on primordial black hole evaporation
Korwar, Mrunal; Profumo, Stefano
The Hawking evaporation process, leading to the production of detectable particle species, constrains the abundance of light black holes, presumably of primordial origin. Here, we reconsider and correct constraints from soft gamma-ray observations, including of the gamma-ray line, at 511 keV, produced by electron-positron pair-annihilation, where …