Search Publications

ALMA Evidence for Ram Pressure Compression and Stripping of Molecular Gas in the Virgo Cluster Galaxy NGC 4402
DOI: 10.3847/1538-4357/abaf54 Bibcode: 2020ApJ...901...95C

Rubio, M.; Pompei, E.; Vlahakis, C. +5 more

High-resolution (1″ × 2″) Atacama Large Millimeter Array CO(2-1) observations of the ram pressure stripped galaxy NGC 4402 in the Virgo cluster show some of the clearest evidence yet for the impacts of ram pressure on the molecular interstellar medium (ISM) of a galaxy. The eastern side of the galaxy at r ∼ 4.5 kpc, upon which ram pressure is inci…

2020 The Astrophysical Journal
eHST 38
Orbital Stability of Circumstellar Planets in Binary Systems
DOI: 10.3847/1538-3881/ab64fa Bibcode: 2020AJ....159...80Q

Li, Gongjie; Kostov, Veselin; Haghighipour, Nader +1 more

Planets that orbit only one of the stars in stellar binary systems (i.e., circumstellar) are dynamically constrained to a limited range of orbital parameters, and understanding conditions on their stability is thus of great importance in exoplanet searches. We perform ∼700 million N-body simulations to identify how stability regions depend on prop…

2020 The Astronomical Journal
Gaia 38
FRagmentation and Evolution of Dense Cores Judged by ALMA (FREJA). I. Overview: Inner ∼1000 au Structures of Prestellar/Protostellar Cores in Taurus
DOI: 10.3847/1538-4357/ab9ca7 Bibcode: 2020ApJ...899...10T

Inutsuka, Shu-ichiro; André, Philippe; Tokuda, Kazuki +11 more

We have performed survey-type observations in 1 mm continuum and molecular lines toward dense cores (32 prestellar + 7 protostellar) with an average density of ≳105 cm-3 in the Taurus molecular clouds using the Atacama Large Millimeter/submillimeter Array-Atacama Compact Array (ALMA-ACA) stand-alone mode with an angular resol…

2020 The Astrophysical Journal
Herschel 38
Kepler-1661 b: A Neptune-sized Kepler Transiting Circumbinary Planet around a Grazing Eclipsing Binary
DOI: 10.3847/1538-3881/ab665b Bibcode: 2020AJ....159...94S

Torres, Guillermo; Cochran, William D.; Endl, Michael +7 more

We report the discovery of a Neptune-sized ( ${R}_{p}=3.87\pm 0.06{R}_{\oplus }$ ) transiting circumbinary planet, Kepler-1661 b, found in the Kepler photometry. The planet has a period of ∼175 days and its orbit precesses with a period of only 35 yr. The precession causes the alignment of the orbital planes to vary, and the planet is in a transit…

2020 The Astronomical Journal
Gaia 38
Mutual Orbital Inclinations between Cold Jupiters and Inner Super-Earths
DOI: 10.3847/1538-3881/ab5c1d Bibcode: 2020AJ....159...38M

Winn, Joshua N.; Kawahara, Hajime; Masuda, Kento

Previous analyses of Doppler and Kepler data have found that Sun-like stars hosting “cold Jupiters” (giant planets with a ≳ 1 au) almost always host “inner super-Earths” (1-4 R , a ≲ 1 au). Here we attempt to determine the degree of alignment between the orbital planes of the cold Jupiters and the inner super-Earths. The key observatio…

2020 The Astronomical Journal
Gaia 38
The Gemini Planet Imager Exoplanet Survey: Dynamical Mass of the Exoplanet β Pictoris b from Combined Direct Imaging and Astrometry
DOI: 10.3847/1538-3881/ab5b92 Bibcode: 2020AJ....159...71N

Duchêne, Gaspard; Esposito, Thomas M.; Oppenheimer, Rebecca +51 more

We present new observations of the planet β Pictoris b from 2018 with the Gemini Planet Imager (GPI), the first GPI observations following conjunction. Based on these new measurements, we perform a joint orbit fit to the available relative astrometry from ground-based imaging, the Hipparcos Intermediate Astrometric Data (IAD), and the Gaia DR2 pos…

2020 The Astronomical Journal
Gaia Hipparcos 38
Common dynamo scaling in slowly rotating young and evolved stars
DOI: 10.1038/s41550-020-1039-x Bibcode: 2020NatAs...4..658L

Spada, Federico; Lehtinen, Jyri J.; Käpylä, Maarit J. +2 more

One interpretation of the activity and magnetism of late-type stars is that these both intensify with decreasing Rossby number up to a saturation level1-3, suggesting that stellar dynamos depend on both rotation and convective turbulence4. Some studies have claimed, however, that rotation alone suffices to parametrize this sc…

2020 Nature Astronomy
Gaia 38
Spectroscopic confirmation of a mature galaxy cluster at a redshift of 2
DOI: 10.1038/s41586-019-1829-4 Bibcode: 2020Natur.577...39W

Brammer, G.; Stanford, S. A.; Allen, S. W. +6 more

Galaxy clusters are the most massive virialized structures in the Universe and are formed through the gravitational accretion of matter over cosmic time1. The discovery2 of an evolved galaxy cluster at redshift z = 2, corresponding to a look-back time of 10.4 billion years, provides an opportunity to study its properties. The…

2020 Nature
eHST 38
Active red giants: Close binaries versus single rapid rotators
DOI: 10.1051/0004-6361/202037781 Bibcode: 2020A&A...639A..63G

Gaulme, Patrick; Vrard, Mathieu; McKeever, Jean +7 more

Oscillating red-giant stars have provided a wealth of asteroseismic information regarding their interiors and evolutionary states, which enables detailed studies of the Milky Way. The objective of this work is to determine what fraction of red-giant stars shows photometric rotational modulation, and understand its origin. One of the underlying que…

2020 Astronomy and Astrophysics
Gaia 38
IRIS Observations of Short-term Variability in Moss Associated with Transient Hot Coronal Loops
DOI: 10.3847/1538-4357/ab63cf Bibcode: 2020ApJ...889..124T

Polito, Vanessa; Testa, Paola; De Pontieu, Bart

We observed rapid variability (≲60 s) at the footpoints of transient, hot (∼8-10 MK) coronal loops in active region cores, with the Interface Region Imaging Spectrograph (IRIS). The high spatial (∼0"33) and temporal (≲5-10 s) resolution of IRIS is often crucial for the detection of this variability. We show how, in combination with 1D RADYN loop m…

2020 The Astrophysical Journal
IRIS 38