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The flaring X-ray corona in the quasar PDS 456
DOI: 10.1093/mnras/staa3377 Bibcode: 2021MNRAS.500.1974R

Porquet, D.; Reeves, J. N.; Braito, V. +3 more

New Swift monitoring observations of the variable, radio-quiet quasar, PDS 456, are presented. A bright X-ray flare was captured in 2018 September, the flux increasing by a factor of 4 and with a doubling time-scale of 2 d. From the light crossing argument, the coronal size is inferred to be ≲30 gravitational radii for a black hole mass of 10

2021 Monthly Notices of the Royal Astronomical Society
XMM-Newton 22
Jupiter's Temperate Belt/Zone Contrasts Revealed at Depth by Juno Microwave Observations
DOI: 10.1029/2021JE006858 Bibcode: 2021JGRE..12606858F

Bolton, S.; Fletcher, L. N.; Wong, M. H. +12 more

Juno microwave radiometer (MWR) observations of Jupiter's midlatitudes reveal a strong correlation between brightness temperature contrasts and zonal winds, confirming that the banded structure extends throughout the troposphere. However, the microwave brightness gradient is observed to change sign with depth: the belts are microwave-bright in the…

2021 Journal of Geophysical Research (Planets)
eHST 22
Dynamical Analysis of the Dark Matter and Central Black Hole Mass in the Dwarf Spheroidal Leo I
DOI: 10.3847/1538-4357/ac0c79 Bibcode: 2021ApJ...921..107B

Gebhardt, Karl; Zeimann, Greg; Thomas, Jens +4 more

We measure the central kinematics for the dwarf spheroidal galaxy Leo I using integrated-light measurements and previously published data. We find a steady rise in the velocity dispersion from 300″ into the center. The integrated-light kinematics provide a velocity dispersion of 11.76 ± 0.66 km s-1 inside 75″. After applying appropriate…

2021 The Astrophysical Journal
eHST 22
Multi-thermal atmosphere of a mini-solar flare during magnetic reconnection observed with IRIS
DOI: 10.1051/0004-6361/202039229 Bibcode: 2021A&A...645A..80J

Heinzel, Petr; Aulanier, Guillaume; Schmieder, Brigitte +4 more

Context. The Interface Region Imaging Spectrograph (IRIS) with its high spatial and temporal resolution facilitates exceptional plasma diagnostics of solar chromospheric and coronal activity during magnetic reconnection.
Aims: The aim of this work is to study the fine structure and dynamics of the plasma at a jet base forming a mini-flare bet…

2021 Astronomy and Astrophysics
IRIS 22
Confirmation and physical characterization of the new bulge globular cluster Patchick 99 from the VVV and Gaia surveys
DOI: 10.1051/0004-6361/202039255 Bibcode: 2021A&A...649A..86G

Minniti, D.; Ripepi, V.; Alonso-García, J. +4 more

Context. Globular clusters (GCs) are recognised as important tools for understanding the formation and evolution of the Milky Way (MW) because they are the oldest objects in our Galaxy. Unfortunately, the known sample in our MW is still incomplete, especially towards the innermost regions, because of the high differential reddening, extinction, an…

2021 Astronomy and Astrophysics
Gaia 22
A Blueprint for the Milky Way's Stellar Populations. III. Spatial Distributions and Population Fractions of Local Halo Stars
DOI: 10.3847/1538-4357/ac07a4 Bibcode: 2021ApJ...918...74A

Beers, Timothy C.; An, Deokkeun

We analyze the observed spatial, chemical and dynamical distributions of local metal-poor stars, based on photometrically derived metallicity and distance estimates along with proper motions from the Gaia mission. Along the Galactic prime meridian, we identify stellar populations with distinct properties in the metallicity versus rotational veloci…

2021 The Astrophysical Journal
Gaia 22
Annual Appearance of Hydrogen Chloride on Mars and a Striking Similarity With the Water Vapor Vertical Distribution Observed by TGO/NOMAD
DOI: 10.1029/2021GL092506 Bibcode: 2021GeoRL..4892506A

Aoki, S.; Vandaele, A. C.; Daerden, F. +23 more

Hydrogen chloride (HCl) was recently discovered in the atmosphere of Mars by two spectrometers onboard the ExoMars Trace Gas Orbiter. The reported detection made in Martian Year 34 was transient, present several months after the global dust storm during the southern summer season. Here, we present the full data set of vertically resolved HCl detec…

2021 Geophysical Research Letters
ExoMars-16 22
The connection between star formation and supermassive black hole activity in the local Universe
DOI: 10.1093/mnras/stab1794 Bibcode: 2021MNRAS.506.2619T

Vignali, C.; Carrera, F.; Paolillo, M. +4 more

We study the nuclear (AGN) activity in the local Universe (z < 0.33) and its correlation with the host galaxy properties, derived from a Sloan Digital Sky Survey sample with spectroscopic star-formation rate (SFR) and stellar mass determination. To quantify the level of AGN activity we used the XMM-Newton Serendipitous Source Catalogue. Applyin…

2021 Monthly Notices of the Royal Astronomical Society
XMM-Newton 22
Subaru/HSC deep optical imaging of infrared sources in the AKARI North Ecliptic Pole-Wide field
DOI: 10.1093/mnras/staa3080 Bibcode: 2021MNRAS.500.5024O

Momose, Rieko; Goto, Tomotsugu; Kim, Seong Jin +8 more

We present a five-broad-band (grizy) photometric catalogue of Subaru/Hyper Suprime-Cam (HSC) optical imaging observations at around the North Ecliptic Pole (NEP) where the AKARI infrared (IR) satellite conducted a large survey (NEP-Wide survey). The observations cover almost all the NEP-Wide survey field down to the depth of 28.1, 26.8, 26.3, 25.5…

2021 Monthly Notices of the Royal Astronomical Society
AKARI Herschel 22
Robotic Reverberation Mapping of the Southern Seyfert NGC 3783
DOI: 10.3847/1538-4357/abccd4 Bibcode: 2021ApJ...906...50B

Onken, Christopher A.; Bentz, Misty C.; Valluri, Monica +1 more

We present spectroscopic and photometric monitoring of NGC 3783 conducted throughout the first half of 2020. Time delays between the continuum variations and the response of the broad optical emission lines were clearly detected, and we report reverberation measurements for Hβ, He II λ4686, Hγ, and Hδ. From the time delay in the broad Hβ emission …

2021 The Astrophysical Journal
eHST 22