Search Publications

The Fifth Candidate for an Intermediate-mass Black Hole in the Galactic Center
DOI: 10.3847/1538-4357/ab6f6f Bibcode: 2020ApJ...890..167T

Oka, Tomoharu; Tsujimoto, Shiho; Iwata, Yuhei +2 more

We report the results of high-resolution molecular line observations of the high-velocity compact cloud HCN-0.085-0.094 with the Atacama Large Millimeter/submillimeter Array. The HCN J = 4-3, HCO+ J = 4-3, and CS J = 7-6 line images reveal that HCN-0.085-0.094 consists mainly of three small clumps with extremely broad velocity widths. E…

2020 The Astrophysical Journal
eHST 27
Electron Pitch-Angle Distribution in Earth's Magnetotail: Pancake, Cigar, Isotropy, Butterfly, and Rolling-Pin
DOI: 10.1029/2020JA027777 Bibcode: 2020JGRA..12527777L

Wang, Z.; Xu, Y.; Chen, G. +4 more

Electron pitch-angle distributions, including isotropy, pancake, cigar, butterfly, and recently discovered rolling-pin distributions, are crucial to understanding electron dynamics in the magnetotail. However, occurrence rates of these distributions remain unclear. Here, for the first time, we reveal the occurrence rates of these distributions in …

2020 Journal of Geophysical Research (Space Physics)
Cluster 26
Broadband Selection, Spectroscopic Identification, and Physical Properties of a Population of Extreme Emission-line Galaxies at 3 < z < 3.7
DOI: 10.3847/1538-4357/abc174 Bibcode: 2020ApJ...904..180O

Harikane, Yuichi; Shibuya, Takatoshi; Suzuki, Tomoko L. +7 more

We present the selection, spectroscopic identification, and physical properties of extreme emission-line galaxies (EELGs) at 3 < z < 3.7, aiming at studying physical properties of an analog population of star-forming galaxies (SFGs) at the epoch of reionization. The sample is selected based on the excess in the observed Ks broadband flux rel…

2020 The Astrophysical Journal
eHST 26
Multiple mineral horizons in layered outcrops at Mawrth Vallis, Mars, signify changing geochemical environments on early Mars
DOI: 10.1016/j.icarus.2020.113634 Bibcode: 2020Icar..34113634B

Seelos, Frank P.; Murchie, Scott L.; Horgan, Briony +6 more

Refined calibrations of CRISM images are enabling identification of smaller deposits of unique aqueous materials on Mars that reveal changing environmental conditions at the region surrounding Mawrth Vallis. Through characterization of these clay-sulfate assemblages and their association with the layered, phyllosilicate units of this region, more …

2020 Icarus
MEx 26
MCR-TRGB: A Multiwavelength-covariant, Robust Tip of the Red Giant Branch Measurement Method
DOI: 10.3847/1538-4357/ab9cbb Bibcode: 2020ApJ...898...57D

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 …

2020 The Astrophysical Journal
eHST 26
Ultra-short-period Planets Are Stable against Tidal Inspiral
DOI: 10.3847/1538-3881/aba74f Bibcode: 2020AJ....160..138H

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…

2020 The Astronomical Journal
Gaia 26
GOODS-ALMA: Using IRAC and VLA to probe fainter millimeter galaxies
DOI: 10.1051/0004-6361/202038310 Bibcode: 2020A&A...643A..53F

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…

2020 Astronomy and Astrophysics
eHST 26
Impulsive coronal heating during the interaction of surface magnetic fields in the lower solar atmosphere
DOI: 10.1051/0004-6361/202039099 Bibcode: 2020A&A...644A.130C

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 …

2020 Astronomy and Astrophysics
IRIS 26
Hyper Suprime-Cam Low Surface Brightness Galaxies. II. A Hubble Space Telescope Study of the Globular Cluster Systems of Ultradiffuse Galaxies in Groups
DOI: 10.3847/1538-4357/abb1b2 Bibcode: 2020ApJ...902...45S

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…

2020 The Astrophysical Journal
eHST 26
The RAdial Velocity Experiment (RAVE): Parameterisation of RAVE spectra based on convolutional neural networks
DOI: 10.1051/0004-6361/202038271 Bibcode: 2020A&A...644A.168G

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…

2020 Astronomy and Astrophysics
Gaia 26