Search Publications
MCR-TRGB: A Multiwavelength-covariant, Robust Tip of the Red Giant Branch Measurement Method
Dalcanton, J. J.; Boyer, M. L.; Williams, B. F. +2 more
We present a new method to measure colors and magnitudes of the tip of the red giant branch (TGRB) in multiple bandpasses simultaneously by fitting an n-dimensional Gaussian to photometry of candidate tip stars. We demonstrate that this method has several advantages over traditional edge detection, particularly in regimes where the TRGB magnitude …
Ultra-short-period Planets Are Stable against Tidal Inspiral
Schlaufman, Kevin C.; Hamer, Jacob H.
It has been unambiguously shown both in individual systems and at the population level that hot Jupiters experience tidal inspiral before the end of their host stars' main-sequence lifetimes. Ultra-short-period (USP) planets have orbital periods P < 1 day, rocky compositions, and are expected to experience tidal decay on similar timescales to h…
GOODS-ALMA: Using IRAC and VLA to probe fainter millimeter galaxies
Magnelli, B.; Daddi, E.; Elbaz, D. +33 more
In this paper, we extend the source detection in the GOODS-ALMA field (69 arcmin2, 1σ ≃ 0.18 mJy beam-1) to deeper levels than presented in our previous work. Using positional information at 3.6 and 4.5 µm (from Spitzer-IRAC) as well as the Very Large Array (VLA) at 3 GHz, we explore the presence of galaxies detected at…
Impulsive coronal heating during the interaction of surface magnetic fields in the lower solar atmosphere
Peter, H.; Chitta, L. P.; Solanki, S. K. +1 more
Coronal plasma in the cores of solar active regions is impulsively heated to more than 5 MK. The nature and location of the magnetic energy source responsible for such impulsive heating is poorly understood. Using observations of seven active regions from the Solar Dynamics Observatory, we found that a majority of coronal loops hosting hot plasma …
Hyper Suprime-Cam Low Surface Brightness Galaxies. II. A Hubble Space Telescope Study of the Globular Cluster Systems of Ultradiffuse Galaxies in Groups
Greene, Jenny E.; Goulding, Andy D.; Beaton, Rachael L. +4 more
We increase the sample of ultradiffuse galaxies (UDGs) in lower-density environments with characterized globular cluster (GC) populations using new Hubble Space Telescope observations of nine UDGs in group environments. While the bulk of our UDGs have GC abundances consistent with normal dwarf galaxies, two of these UDGs have excess GC populations…
The RAdial Velocity Experiment (RAVE): Parameterisation of RAVE spectra based on convolutional neural networks
Guiglion, G.; Valentini, M.; Anders, F. +22 more
Context. Data-driven methods play an increasingly important role in the field of astrophysics. In the context of large spectroscopic surveys of stars, data-driven methods are key in deducing physical parameters for millions of spectra in a short time. Convolutional neural networks (CNNs) enable us to connect observables (e.g. spectra, stellar magn…
Imaging and Spectral Study on the Null Point of a Fan-spine Structure During a Solar Flare
Yang, Shuhong; Zhang, Jun; Zhong, Ze +3 more
Using the multi-instrument observations, we make the first simultaneous imaging and spectral study on the null point of a fan-spine magnetic topology during a solar flare. When magnetic reconnection occurs at the null point, the fan-spine configuration brightens in the (extreme-)ultraviolet channels. In the Hα images, the fan-spine structure is pa…
A large amount of diffuse molecular gases in the bar of the strongly barred galaxy NGC 1300: cause of the low star formation efficiency
Ohta, Kouji; Maeda, Fumiya; Fujimoto, Yusuke +2 more
In many barred galaxies, star formation efficiency (SFE) in the bar is lower than those in the arm and bar-end, and its cause has still not been clear. Focusing on the strongly barred galaxy NGC 1300, we investigate the possibility that the presence of a large amount of diffuse molecular gas, which would not contribute to the SF, makes the SFE low…
The VMC survey. XXXVIII. Proper motion of the Magellanic Bridge
de Grijs, Richard; Ripepi, Vincenzo; Petr-Gotzens, Monika G. +14 more
Context. The Magellanic Clouds are a nearby pair of interacting dwarf galaxies and satellites of the Milky Way. Studying their kinematic properties is essential to understanding their origin and dynamical evolution. They have prominent tidal features and the kinematics of these features can give hints about the formation of tidal dwarfs, galaxy me…
Revealing the Dark Threads of the Cosmic Web
Tripp, Todd M.; Prochaska, J. Xavier; Tejos, Nicolas +4 more
Modern cosmology predicts that matter in our universe today has assembled into a vast network of filamentary structures colloquially termed the "cosmic web." Because this matter is either electromagnetically invisible (I.e., dark) or too diffuse to image in emission, tests of this cosmic web paradigm are limited. Wide-field surveys do reveal web-l…