Search Publications

Multi-point analysis of coronal mass ejection flux ropes using combined data from Solar Orbiter, BepiColombo, and Wind
DOI: 10.1051/0004-6361/202140919 Bibcode: 2021A&A...656A..13W

Möstl, C.; Horbury, T. S.; Baumjohann, W. +15 more

Context. The recent launch of Solar Orbiter and the flyby of BepiColombo opened a brief window during which these two spacecraft, along with the existing spacecraft at L1, were positioned in a constellation that allowed for the detailed sampling of any Earth-directed coronal mass ejection (CME). Fortunately, two such events occurred during this ti…

2021 Astronomy and Astrophysics
BepiColombo SolarOrbiter 32
KiDS-1000: Constraints on the intrinsic alignment of luminous red galaxies
DOI: 10.1051/0004-6361/202140706 Bibcode: 2021A&A...654A..76F

Hoekstra, Henk; Heymans, Catherine; Kuijken, Konrad +11 more

We constrain the luminosity and redshift dependence of the intrinsic alignment (IA) of a nearly volume-limited sample of luminous red galaxies selected from the fourth public data release of the Kilo-Degree Survey (KiDS-1000). To measure the shapes of the galaxies, we used two complementary algorithms, finding consistent IA measurements for the ov…

2021 Astronomy and Astrophysics
eHST 32
Which Molecular Cloud Structures Are Bound?
DOI: 10.3847/1538-4357/ac1425 Bibcode: 2021ApJ...920..126E

Miville-Deschênes, Marc-Antoine; Heyer, Mark; Evans, Neal J., II +2 more

We analyze surveys of molecular cloud structures defined by tracers ranging from CO J = 1 → 0 through 13CO J = 1 → 0 to dust emission together with NH3 data. The mean value of the virial parameter and the fraction of mass in bound structures depends on the method used to identify structures. Generally, the virial parameter de…

2021 The Astrophysical Journal
eHST 32
Evidence for Ultra-diffuse Galaxy Formation through Tidal Heating of Normal Dwarfs
DOI: 10.3847/1538-4357/ac0975 Bibcode: 2021ApJ...919...72J

Sand, David J.; Jones, Michael G.; Zaritsky, Dennis +5 more

We have followed up two ultra-diffuse galaxies (UDGs), detected adjacent to stellar streams, with Hubble Space Telescope (HST) imaging and H I mapping with the Jansky Very Large Array in order to investigate the possibility that they might have a tidal origin. With the HST F814W and F555W images we measure the globular cluster (GC) counts for NGC …

2021 The Astrophysical Journal
eHST 32
TOI-674b: An oasis in the desert of exo-Neptunes transiting a nearby M dwarf
DOI: 10.1051/0004-6361/202140718 Bibcode: 2021A&A...653A..60M

Bouchy, F.; Korth, J.; Doyon, R. +59 more

Context. The NASA mission TESS is currently doing an all-sky survey from space to detect transiting planets around bright stars. As part of the validation process, the most promising planet candidates need to be confirmed and characterized using follow-up observations.
Aims: In this article, our aim is to confirm the planetary nature of the t…

2021 Astronomy and Astrophysics
Gaia 32
The Second Discovery from the COCONUTS Program: A Cold Wide-orbit Exoplanet around a Young Field M Dwarf at 10.9 pc
DOI: 10.3847/2041-8213/ac1123 Bibcode: 2021ApJ...916L..11Z

Siverd, Robert J.; Claytor, Zachary R.; Dupuy, Trent J. +3 more

We present the identification of the second discovery from the COol Companions ON Ultrawide orbiTS (COCONUTS) program, the COCONUTS-2 system, composed of the M3 dwarf L 34-26 and the T9 dwarf WISEPA J075108.79-763449.6. Given their common proper motions and parallaxes, these two field objects constitute a physically bound pair with a projected sep…

2021 The Astrophysical Journal
Gaia 32
Photometric Variability as a Proxy for Magnetic Activity and Its Dependence on Metallicity
DOI: 10.3847/1538-4357/abed47 Bibcode: 2021ApJ...912..127S

Amard, Louis; See, Victor; Roquette, Julia +1 more

Understanding how the magnetic activity of low-mass stars depends on their fundamental parameters is an important goal of stellar astrophysics. Previous studies have shown that activity levels are largely determined by the stellar Rossby number, defined as the rotation period divided by the convective turnover time. However, we currently have litt…

2021 The Astrophysical Journal
Gaia 32
Star formation in 'the Brick': ALMA reveals an active protocluster in the Galactic centre cloud G0.253+0.016
DOI: 10.1093/mnras/stab415 Bibcode: 2021MNRAS.503...77W

Ho, Luis C.; Jackson, James M.; Lu, Xing +16 more

G0.253+0.016, aka 'the Brick', is one of the most massive (>105 M) and dense (>104 cm-3) molecular clouds in the Milky Way's Central Molecular Zone. Previous observations have detected tentative signs of active star formation, most notably a water maser that is associated with a dust continuum sou…

2021 Monthly Notices of the Royal Astronomical Society
Herschel 31
Direct characterization of young giant exoplanets at high spectral resolution by coupling SPHERE and CRIRES+
DOI: 10.1051/0004-6361/202038517 Bibcode: 2021A&A...646A.150O

Reiners, A.; Lopez, M.; Costille, A. +19 more

Studies of atmospheres of directly imaged extrasolar planets with high-resolution spectrographs have shown that their characterization is predominantly limited by noise on the stellar halo at the location of the studied exoplanet. An instrumental combination of high-contrast imaging and high spectral resolution that suppresses this noise and resol…

2021 Astronomy and Astrophysics
Hipparcos 31
An Improved Hertzsprung-Russell Diagram for the Orion Trapezium Cluster
DOI: 10.3847/1538-4357/abcec8 Bibcode: 2021ApJ...908...49F

Fang, Min; Pascucci, Ilaria; Apai, Dániel +1 more

We present a study of the Trapezium cluster in Orion. We analyze flux-calibrated Very Large Telescope/Multi-Unit Spectroscopic Explorer spectra of 361 stars to simultaneously measure the spectral types, reddening, and the optical veiling due to accretion. We find that the extinction law from Cardelli et al. with a total-to-selective extinction val…

2021 The Astrophysical Journal
eHST 31