Search Publications
Polarization of the Corona Observed During the 2017 and 2019 Total Solar Eclipses
Hanaoka, Yoichiro; Sakai, Yoshiaki; Takahashi, Koichi
We carried out polarimetric observations of the white-light corona during the total solar eclipses that occurred on August 21, 2017, and July 2, 2019, and successfully obtained data at two different sites for both eclipses. After eliminating the sky background, we derived the brightness, polarization brightness, and degree of polarization of the K…
The HASHTAG Project: The First Submillimeter Images of the Andromeda Galaxy from the Ground
Ho, Luis C.; Lee, Chien-Hsiu; Clark, Christopher J. R. +46 more
Observing nearby galaxies with submillimeter telescopes on the ground has two major challenges. First, the brightness is significantly reduced at long submillimeter wavelengths compared to the brightness at the peak of the dust emission. Second, it is necessary to use a high-pass spatial filter to remove atmospheric noise on large angular scales, …
Subaru Hyper Suprime-Cam revisits the large-scale environmental dependence on galaxy morphology over 360 deg2 at z = 0.3-0.6
Shimakawa, Rhythm; Tanaka, Masayuki; Tanaka, Takumi S. +1 more
This study investigates the role of large-scale environments on the fraction of spiral galaxies at z = 0.3-0.6 sliced to three redshift bins of Δz = 0.1. Here, we sample 276220 massive galaxies in a limited stellar mass of 5 × 1010 solar mass (~M*) over 360 deg2, as obtained from the Second Public Data Release of the Hyper Su…
Multiwavelength constraints on the unidentified Galactic TeV sources HESS J1427-608, HESS J1458-608, and new VHE γ-ray source candidates
Lemoine-Goumard, M.; Vasileiadis, G.; Renaud, M. +1 more
Aims: Among the γ-ray sources discovered at high and very-high energies, a large fraction still lack a clear identification. In particular, the H.E.S.S. Galactic Plane Survey (HGPS) revealed 78 TeV sources among which 47 are not clearly associated with a known object. Multiwavelength data can help identify the origin of the very-high energy γ…
The Challenge to MOND from Ultra-faint Dwarf Galaxies
Loeb, Abraham; Safarzadeh, Mohammadtaher
Modified Newtonian dynamics (MOND) at low acceleration has been astonishingly powerful at explaining the rotation curve of galaxies and the relation between the baryonic content of the galaxies and their observed circular velocity, known as the baryonic TullyFisher relationship. It is known that MOND fails at explaining the observed velocity dispe…
The Transition from Diffuse Molecular Gas to Molecular Cloud Material in Taurus
Kim, Hwihyun; Federman, S. R.; Lambert, David L. +6 more
We study four lines of sight that probe the transition from diffuse molecular gas to molecular cloud material in Taurus. Measurements of atomic and molecular absorption are used to infer the distribution of species and the physical conditions toward stars behind the Taurus Molecular Cloud (TMC). New high-resolution spectra at visible and near-IR w…
Time evolution of gaps in stellar streams in axisymmetric Stäckel potentials
Helmi, Amina; Koppelman, Helmer H.
Context. When a subhalo interacts with a cold stellar stream, the otherwise nearly smooth distribution of stars is disturbed, and this creates a gap. The properties of these gaps depend on the interaction parameters. Their characterisation could thus lead to a determination of the mass spectrum of the perturbers and might reveal the existence of d…
The key impact of the host star's rotational history on the evolution of TOI-849b
Buldgen, G.; Eggenberger, P.; Bourrier, V. +2 more
Context. TOI-849b is one of the few planets populating the hot-Neptune desert and it is the densest Neptune-sized one discovered so far. Its extraordinary proximity to the host star, together with the absence of a massive H/He envelope on top of the 40.8 M⊕ rocky core, calls into question the role played by the host star in the evolutio…
Filament Eruption Driving EUV Loop Contraction and Then Expansion above a Stable Filament
Schmieder, Brigitte; Joshi, Reetika; Chandra, Ramesh +2 more
We analyze the observations of EUV loop evolution associated with the filament eruption located at the border of an active region (AR). The event SOL2013-03-16T14:00 was observed with a large difference in view point by the Solar Dynamics Observatory and Solar Terrestrial Relations Observatory. The filament height is fitted with the sum of a linea…
DIISC-I: The Discovery of Kinematically Anomalous H I Clouds in M 100
Heckman, Timothy M.; Nelson, Dylan; Thilker, David +10 more
We report the discovery of two kinematically anomalous atomic hydrogen (H I) clouds in M 100 (NGC 4321), which was observed as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium (DIISC) survey in H I 21 cm at 3.3 km s-1 spectroscopic and 44″ × 30″ spatial resolution using the Karl…