Search Publications

Fifty Years of 3 He-rich Events
DOI: 10.3389/fspas.2021.760261 Bibcode: 2021FrASS...8..164R

Reames, Donald V.

The early 1970s saw a new and surprising feature in the composition of solar energetic particles (SEPs), resonant enhancements up to 10,000-fold in the ratio 3He/4He that could even make 3He dominant over H in rare events. It was soon learned that these events also had enhancements in the abundances of heavier elements, such as a factor of ~10 enh…

2021 Frontiers in Astronomy and Space Sciences
SOHO 15
Uncovering fossils of the distant Milky Way with UNIONS: NGC 5466 and its stellar stream
DOI: 10.1093/mnras/stab2325 Bibcode: 2021MNRAS.507.1923J

Jensen, Jaclyn; McConnachie, Alan W.; Cuillandre, Jean-Charles +9 more

We examine the spatial clustering of blue horizontal branch (BHB) stars from the u-band of the Canada-France Imaging Survey (CFIS, a component of the Ultraviolet Near-Infrared Optical Northern Survey, or UNIONS). All major groupings of stars are associated with previously known satellites, and among these is NGC 5466, a distant (16 kpc) globular c…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 15
Connecting solar flare hard X-ray spectra to in situ electron spectra. A comparison of RHESSI and STEREO/SEPT observations
DOI: 10.1051/0004-6361/202141365 Bibcode: 2021A&A...654A..92D

Klein, K. -L.; Dresing, N.; Warmuth, A. +4 more


Aims: We aim to constrain the acceleration, injection, and transport processes of flare-accelerated energetic electrons by comparing their characteristics at the Sun with those injected into interplanetary space.
Methods: We have identified 17 energetic electron events well-observed with the SEPT instrument aboard STEREO which show a cle…

2021 Astronomy and Astrophysics
SOHO 15
Clumpiness of observed and simulated cold circumgalactic gas
DOI: 10.1093/mnras/stab1673 Bibcode: 2021MNRAS.505.6195A

Hamanowicz, Aleksandra; Zanella, Anita; Péroux, Céline +3 more

Determining the clumpiness of matter around galaxies is pivotal to a full understanding of the spatially inhomogeneous, multiphase gas in the circumgalactic medium (CGM). We combine high spatially resolved 3D observations with hydrodynamical cosmological simulations to measure the cold circumgalactic gas clumpiness. We present new adaptive-optics-…

2021 Monthly Notices of the Royal Astronomical Society
eHST 15
Relativistic viscous accretion flow model for ULX sources: a case study for IC 342 X-1
DOI: 10.1093/mnras/stab2307 Bibcode: 2021MNRAS.507.2777D

Agrawal, Vivek K.; Nandi, Anuj; Das, Santabrata +2 more

In this paper, we develop a model formalism to study the structure of a relativistic, viscous, optically thin, advective accretion flow around a rotating black hole in presence of radiative coolings. We use this model to examine the physical parameters of the ultra-luminous X-ray sources (ULXs), namely mass (MBH), spin (ak), …

2021 Monthly Notices of the Royal Astronomical Society
XMM-Newton 15
The HOSTS Survey: Evidence for an Extended Dust Disk and Constraints on the Presence of Giant Planets in the Habitable Zone of β Leo
DOI: 10.3847/1538-3881/abe3ff Bibcode: 2021AJ....161..186D

Absil, O.; Bryden, G.; Ertel, S. +38 more

The young (50-400 Myr) A3V star β Leo is a primary target to study the formation history and evolution of extrasolar planetary systems as one of the few stars with known hot (∼1600 K), warm (∼600 K), and cold (∼120 K) dust belt components. In this paper, we present deep mid-infrared measurements of the warm dust brightness obtained with the Large …

2021 The Astronomical Journal
Herschel 15
Cataclysmic Variables in the Second Year of the Zwicky Transient Facility
DOI: 10.3847/1538-3881/ac0efb Bibcode: 2021AJ....162...94S

Duev, Dmitry A.; Riddle, Reed; Szkody, Paula +17 more

Using a filter in the GROWTH Marshal based on color and the amplitude and timescale of variability, we have identified 372 objects as known or candidate cataclysmic variables (CVs) during the second year of the operation of the Zwicky Transient Facility. From the available difference imaging data, we found that 93 are previously confirmed CVs and …

2021 The Astronomical Journal
Gaia 15
Evolutionary map of the Universe (EMU): Compact radio sources in the SCORPIO field towards the galactic plane
DOI: 10.1093/mnras/stab028 Bibcode: 2021MNRAS.502...60R

Umana, G.; Filipović, M. D.; Michałowski, M. J. +26 more

We present observations of a region of the Galactic plane taken during the Early Science Program of the Australian Square Kilometre Array Pathfinder (ASKAP). In this context, we observed the SCORPIO field at 912 MHz with an uncompleted array consisting of 15 commissioned antennas. The resulting map covers a square region of ∼40 deg2, ce…

2021 Monthly Notices of the Royal Astronomical Society
Gaia Herschel 15
An X-ray and radio study of the Hubble Frontier Field cluster Abell S1063
DOI: 10.1093/mnras/stab1225 Bibcode: 2021MNRAS.505..480R

Rapetti, David; Rahaman, Majidul; Raja, Ramij +3 more

We present results from Chandra X-ray observations and 325 MHz Giant Metrewave Radio Telescope (GMRT) observations of the massive and X-ray luminous cluster of galaxies Abell S1063. We report the detection of large-scale 'excess brightness' in the residual Chandra X-ray surface brightness map that extends at least 2.7 Mpc towards the north-east fr…

2021 Monthly Notices of the Royal Astronomical Society
eHST 15
Photo-chemo-dynamical analysis and the origin of the bulge globular cluster Palomar 6
DOI: 10.1051/0004-6361/202141768 Bibcode: 2021A&A...656A..78S

Valentini, M.; Anders, F.; Chiappini, C. +7 more

Context. Palomar 6 (Pal6) is a moderately metal-poor globular cluster projected towards the Galactic bulge. A full analysis of the cluster can give hints on the early chemical enrichment of the Galaxy and a plausible origin of the cluster.
Aims: The aim of this study is threefold: a detailed analysis of high-resolution spectroscopic data obta…

2021 Astronomy and Astrophysics
Gaia eHST 15