Search Publications

Disk Masses and Dust Evolution of Protoplanetary Disks around Brown Dwarfs
DOI: 10.3847/1538-4357/ac09e5 Bibcode: 2021ApJ...921..182R

Espaillat, Catherine C.; Rilinger, Anneliese M.

We present the largest sample of brown dwarf (BD) protoplanetary disk spectral energy distributions modeled to date. We compile 49 objects with ALMA observations from four star-forming regions: ρ Ophiuchus, Taurus, Lupus, and Upper Scorpius. Studying multiple regions with various ages enables us to probe disk evolution over time. Specifically, fro…

2021 The Astrophysical Journal
Gaia 19
The First Retrieval of a Substellar Subdwarf: A Cloud-free SDSS J125637.13-022452.4
DOI: 10.3847/1538-4357/ac294e Bibcode: 2021ApJ...923...19G

Gonzales, Eileen C.; Marley, Mark; Faherty, Jacqueline K. +5 more

We present the first retrieval analysis of a substellar subdwarf, SDSS J125637.13-022452.4 (SDSS J1256-0224), using the Brewster retrieval code base. We find SDSS J1256-0224 is best fit by a cloud-free model with an ion (neutral H, H-, and electron) abundance corresponding to ${\left[\mathrm{Fe}/{\rm{H}}\right]}_{\mathrm{ion}}=-1.5$ . H…

2021 The Astrophysical Journal
Gaia 19
Seasonal and Geographical Variability of the Martian Ionosphere From Mars Express Observations
DOI: 10.1029/2020JE006661 Bibcode: 2021JGRE..12606661G

González-Galindo, F.; Němec, F.; Tellmann, S. +4 more

We study the seasonal and geographical variability of the peak electron density and the altitude of the main ionospheric peak at Mars. For this purpose, we use the data obtained by the ESA Mars Express mission, namely by the radar MARSIS and the radio occultation experiment MaRS. The accumulation of data during the long lifetime of Mars Express pr…

2021 Journal of Geophysical Research (Planets)
MEx 18
Multiscale views of an Alfvénic slow solar wind: 3D velocity distribution functions observed by the Proton-Alpha Sensor of Solar Orbiter
DOI: 10.1051/0004-6361/202141095 Bibcode: 2021A&A...656A..36L

André, N.; Fedorov, A.; Livi, S. +29 more

Context. The Alfvénic slow solar wind is of particular interest, as it is often characterized by intense magnetic turbulence, complex proton 3D velocity distribution functions (VDF), and an ensuing richness of kinetic and dynamic processes.
Aims: We take advantage of the fast time cadence of measurements taken by the Proton-Alpha Sensor (PAS)…

2021 Astronomy and Astrophysics
SolarOrbiter 18
Comparative Analysis of the 2020 November 29 Solar Energetic Particle Event Observed by Parker Solar Probe
DOI: 10.3847/1538-4357/ac157f Bibcode: 2021ApJ...920..123L

Lario, D.; Palmerio, E.; Mitchell, D. G. +15 more

We analyze two specific features of the intense solar energetic particle (SEP) event observed by Parker Solar Probe (PSP) between 2020 November 29 and 2020 December 2. The interplanetary counterpart of the coronal mass ejection (CME) on 2020 November 29 that generated the SEP event (hereafter ICME-2) arrived at PSP (located at 0.8 au from the Sun)…

2021 The Astrophysical Journal
SOHO 18
Earth Wind as a Possible Exogenous Source of Lunar Surface Hydration
DOI: 10.3847/2041-8213/abd559 Bibcode: 2021ApJ...907L..32W

Wei, Y.; Zhang, H.; Xia, L. D. +22 more

Understanding the sources of lunar water is crucial for studying the history of lunar evolution, as well as the interaction of solar wind with the Moon and other airless bodies. Recent orbital spectral observations revealed that the solar wind is a significant exogenous driver of lunar surficial hydration. However, the solar wind is shielded over …

2021 The Astrophysical Journal
Chandrayaan-1 18
Ultramassive Black Holes in the Most Massive Galaxies: MBH-σ versus MBH-Rb
DOI: 10.3847/1538-4357/abceae Bibcode: 2021ApJ...908..134D

Gil de Paz, Armando; Knapen, Johan H.; Dullo, Bililign T.

We investigate the nature of the relations between black hole (BH) mass (MBH) and the central velocity dispersion (σ) and, for core-Sérsic galaxies, the size of the depleted core (Rb). Our sample of 144 galaxies with dynamically determined MBH encompasses 24 core-Sérsic galaxies, thought to be products of gas-poor …

2021 The Astrophysical Journal
eHST 18
Fundamental properties of a selected sample of Ap stars: Inferences from interferometric and asteroseismic constraints
DOI: 10.1051/0004-6361/202040234 Bibcode: 2021A&A...650A.125D

Keszthelyi, Z.; Cunha, M. S.; Holdsworth, D. L. +2 more

Context. Magnetic fields influence the formation and evolution of stars and impact the observed stellar properties. magnetic A-type stars (Ap stars) are a prime example of this. Access to precise and accurate determinations of their stellar fundamental properties, such as masses and ages, is crucial to understand the origin and evolution of fossil…

2021 Astronomy and Astrophysics
Gaia 18
UOCS - III. UVIT catalogue of open clusters with machine learning-based membership using Gaia EDR3 astrometry
DOI: 10.1093/mnras/stab213 Bibcode: 2021MNRAS.503..236J

Jadhav, Vikrant V.; Subramaniam, Annapurni; Pennock, Clara M. +2 more

We present a study of six open clusters (Berkeley 67, King 2, NGC 2420, NGC 2477, NGC 2682, and NGC 6940), using the Ultra Violet Imaging Telescope (UVIT) aboard ASTROSAT and Gaia EDR3. We used combinations of astrometric, photometric, and systematic parameters to train and supervise a machine-learning algorithm along with a Gaussian mixture model…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 18
TESS Discovery of a Super-Earth and Three Sub-Neptunes Hosted by the Bright, Sun-like Star HD 108236
DOI: 10.3847/1538-3881/abd73e Bibcode: 2021AJ....161...85D

Butler, R. Paul; Kristiansen, Martti H.; Terentev, Ivan A. +59 more

We report the discovery and validation of four extrasolar planets hosted by the nearby, bright, Sun-like (G3V) star HD 108236 using data from the Transiting Exoplanet Survey Satellite (TESS). We present transit photometry, reconnaissance, and precise Doppler spectroscopy, as well as high-resolution imaging, to validate the planetary nature of the …

2021 The Astronomical Journal
Gaia 18