Search Publications

Exploring the Evolution of Stellar Rotation Using Galactic Kinematics
DOI: 10.3847/1538-3881/ab91b2 Bibcode: 2020AJ....160...90A

Angus, Ruth; Foreman-Mackey, Daniel; van Saders, Jennifer +9 more

The rotational evolution of cool dwarfs is poorly constrained after ∼1-2 Gyr due to a lack of precise ages and rotation periods for old main-sequence stars. In this work, we use velocity dispersion as an age proxy to reveal the temperature-dependent rotational evolution of low-mass Kepler dwarfs and demonstrate that kinematic ages could be a usefu…

2020 The Astronomical Journal
Gaia 46
Revived fossil plasma sources in galaxy clusters
DOI: 10.1051/0004-6361/201936560 Bibcode: 2020A&A...634A...4M

Di Gennaro, G.; Brunetti, G.; Shimwell, T. W. +10 more

It is well established that particle acceleration by shocks and turbulence in the intra-cluster medium can produce cluster-scale synchrotron emitting sources. However, the detailed physics of these particle acceleration processes is still not well understood. One of the main open questions is the role of fossil relativistic electrons that have bee…

2020 Astronomy and Astrophysics
XMM-Newton 46
ALMA Observations of Multiple CO and C Lines toward the Active Galactic Nucleus of NGC 7469: An X-Ray-dominated Region Caught in the Act
DOI: 10.3847/1538-4357/ab9cb1 Bibcode: 2020ApJ...898...75I

Baba, Shunsuke; Meier, David S.; Turner, Jean L. +15 more

We used the Atacama Large Millimeter/submillimeter Array to map 12CO(J = 1-0), 12CO(J = 2-1), 12CO(J = 3-2), 13CO(J = 2-1), and [C I](3P1-3P0) emission lines around the type 1 active galactic nucleus (AGN) of NGC 7469 (z = 0.0164) at ∼100 pc resolutions. The CO…

2020 The Astrophysical Journal
eHST 46
The soft X-ray excess: NLS1s versus BLS1s
DOI: 10.1093/mnras/stz3005 Bibcode: 2020MNRAS.491..532G

Gliozzi, Mario; Williams, James K.

The soft X-ray excess - the excess of X-rays below 2 keV with respect to the extrapolation of the hard X-ray spectral continuum model - is a very common feature among type 1 active galactic nuclei (AGNs); yet the nature of the soft X-ray excess is still poorly understood and hotly debated. To shed some light on this issue, we have measured in a mo…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 46
Revealing the tidal scars of the Small Magellanic Cloud
DOI: 10.1093/mnras/staa1122 Bibcode: 2020MNRAS.495...98D

Erkal, Denis; Gallart, Carme; De Leo, Michele +3 more

Due to their close proximity, the Large and Small Magellanic Clouds (LMC/SMC) provide natural laboratories for understanding how galaxies form and evolve. With the goal of determining the structure and dynamical state of the SMC, we present new spectroscopic data for ∼3000 SMC red giant branch stars observed using the AAOmega spectrograph at the A…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 46
Star-Gas Surface Density Correlations in 12 Nearby Molecular Clouds. I. Data Collection and Star-sampled Analysis
DOI: 10.3847/1538-4357/ab92a2 Bibcode: 2020ApJ...896...60P

Henning, Thomas; Myers, Philip C.; Gutermuth, Robert A. +15 more

We explore the relation between the stellar mass surface density and the mass surface density of molecular hydrogen gas in 12 nearby molecular clouds that are located at <1.5 kpc distance. The sample clouds span an order-of-magnitude range in mass, size, and star formation rates. We use thermal dust emission from Herschel maps to probe the gas …

2020 The Astrophysical Journal
Gaia Herschel 45
The 2020 April-June super-outburst of OJ 287 and its long-term multiwavelength light curve with Swift: binary supermassive black hole and jet activity
DOI: 10.1093/mnrasl/slaa125 Bibcode: 2020MNRAS.498L..35K

Komossa, S.; Grupe, D.; Parker, M. L. +4 more

We report detection of a very bright X-ray-UV-optical outburst of OJ 287 in 2020 April-June, the second brightest since the beginning of our Swift multiyear monitoring in late 2015. It is shown that the outburst is predominantly powered by jet emission. Optical-UV-X-rays are closely correlated, and the low-energy part of the XMM-Newton spectrum di…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 45
Into the UV: A Precise Transmission Spectrum of HAT-P-41b Using Hubble's WFC3/UVIS G280 Grism
DOI: 10.3847/1538-3881/ab7b78 Bibcode: 2020AJ....159..204W

Wakeford, H. R.; Sing, D. K.; Nikolov, N. +8 more

The ultraviolet-visible wavelength range holds critical spectral diagnostics for the chemistry and physics at work in planetary atmospheres. To date, time-series studies of exoplanets to characterize their atmospheres have relied on several combinations of modes on the Hubble Space Telescope's STIS/COS instruments to access this wavelength regime.…

2020 The Astronomical Journal
eHST 45
Galaxy Sizes Since z = 2 from the Perspective of Stellar Mass Distribution within Galaxies
DOI: 10.3847/1538-4357/abc7cc Bibcode: 2020ApJ...905..170M

Tacchella, Sandro; Mosleh, Moein; Hosseinnejad, Shiva +1 more

How stellar mass assembles within galaxies is still an open question. We present measurements of the stellar mass distribution on kiloparsec-scales for ∼5500 galaxies with stellar masses above $\mathrm{log}({M}_{* }/{M}_{\odot })\geqslant 9.8$ up to redshift 2.0. We create stellar mass maps from Hubble Space Telescope observations by means of the …

2020 The Astrophysical Journal
eHST 45
Prediction of the In Situ Coronal Mass Ejection Rate for Solar Cycle 25: Implications for Parker Solar Probe In Situ Observations
DOI: 10.3847/1538-4357/abb9a1 Bibcode: 2020ApJ...903...92M

Lugaz, Noé; Möstl, Christian; McIntosh, Scott W. +7 more

The Parker Solar Probe (PSP) and Solar Orbiter missions are designed to make groundbreaking observations of the Sun and interplanetary space within this decade. We show that a particularly interesting in situ observation of an interplanetary coronal mass ejection (ICME) by PSP may arise during close solar flybys (<0.1 au). During these times, t…

2020 The Astrophysical Journal
Ulysses 45