Search Publications

No Clear, Direct Evidence for Multiple Protoplanets Orbiting LkCa 15: LkCa 15 bcd are Likely Inner Disk Signals
DOI: 10.3847/2041-8213/ab1b42 Bibcode: 2019ApJ...877L...3C

Henning, Thomas; Currie, Thayne; Dong, Ruobing +30 more

Two studies utilizing sparse aperture-masking (SAM) interferometry and H α differential imaging have reported multiple Jovian companions around the young solar-mass star, LkCa 15 (LkCa 15 bcd): the first claimed direct detection of infant, newly formed planets (“protoplanets”). We present new near-infrared direct imaging/spectroscopy f…

2019 The Astrophysical Journal
Gaia 85
Quantifying the impact of variable BLR diffuse continuum contributions on measured continuum interband delays
DOI: 10.1093/mnras/stz2330 Bibcode: 2019MNRAS.489.5284K

Korista, K. T.; Goad, M. R.

We investigate the contribution of reprocessed continuum emission (1000-10 000 Å) originating in broad-line region (BLR) gas, the diffuse continuum (DC), to the wavelength-dependent continuum delays measured in AGN disc reverberation mapping experiments. Assuming a spherical BLR geometry, we adopt a Local Optimally emitting Cloud (LOC) model for t…

2019 Monthly Notices of the Royal Astronomical Society
IUE eHST 85
Resolved UV and [C II] Structures of Luminous Galaxies within the Epoch of Reionization
DOI: 10.3847/1538-4357/ab2f81 Bibcode: 2019ApJ...881..124M

Schaerer, D.; Mobasher, B.; Ferrara, A. +7 more

We present new deep ALMA and Hubble Space Telescope (HST)/WFC3 observations of MASOSA and VR7, two luminous Lyα emitters (LAEs) at z = 6.5, for which the UV continuum levels differ by a factor of four. No IR dust continuum emission is detected in either, indicating little amounts of obscured star formation and/or high dust temperatures. MASOSA, wi…

2019 The Astrophysical Journal
eHST 85
Gone after one orbit: How cluster environments quench galaxies
DOI: 10.1093/mnras/stz2070 Bibcode: 2019MNRAS.488.5370L

Dolag, Klaus; Biviano, Andrea; Burkert, Andreas +2 more

The effect of galactic orbits on a galaxy's internal evolution within a galaxy cluster environment has been the focus of heated debate in recent years. To understand this connection, we use both the (0.5 Gpc)3 and the Gpc3 boxes from the cosmological hydrodynamical simulation set Magneticum Pathfinder. We investigate the velo…

2019 Monthly Notices of the Royal Astronomical Society
eHST 85
The unbiased frequency of planetary signatures around single and binary white dwarfs using Spitzer and Hubble
DOI: 10.1093/mnras/stz1050 Bibcode: 2019MNRAS.487..133W

Gänsicke, Boris T.; Wilson, Thomas G.; Farihi, Jay +1 more

This paper presents combined Spitzer IRAC and Hubble COS results for a double-blind survey of 195 single and 22 wide binary white dwarfs for infrared excesses and atmospheric metals. The selection criteria include cooling ages in the range 9 to 300 Myr, and hydrogen-rich atmospheres so that the presence of atmospheric metals can be confidently lin…

2019 Monthly Notices of the Royal Astronomical Society
Gaia eHST 84
A Comparison of Flare Forecasting Methods. II. Benchmarks, Metrics, and Performance Results for Operational Solar Flare Forecasting Systems
DOI: 10.3847/1538-4365/ab2e12 Bibcode: 2019ApJS..243...36L

Leka, K. D.; Gallagher, Peter T.; Murray, Sophie A. +21 more

Solar flares are extremely energetic phenomena in our solar system. Their impulsive and often drastic radiative increases, particularly at short wavelengths, bring immediate impacts that motivate solar physics and space weather research to understand solar flares to the point of being able to forecast them. As data and algorithms improve dramatica…

2019 The Astrophysical Journal Supplement Series
SOHO 84
The 3HSP catalogue of extreme and high-synchrotron peaked blazars
DOI: 10.1051/0004-6361/201834526 Bibcode: 2019A&A...632A..77C

Giommi, P.; Padovani, P.; Chang, Y. -L. +2 more


Aims: High-synchrotron peaked blazars (HSPs or HBLs) play a central role in very high-energy (VHE) γ-ray astronomy, and likely in neutrino astronomy. Currently, the largest compilation of HSP blazars, the 2WHSP sample, includes 1691 sources, but it is not complete in the radio or in the X-ray band. In order to provide a larger and more accura…

2019 Astronomy and Astrophysics
XMM-Newton 84
Tidal Interactions between Binary Stars Can Drive Lithium Production in Low-mass Red Giants
DOI: 10.3847/1538-4357/ab27bf Bibcode: 2019ApJ...880..125C

Hogg, David W.; Casey, Andrew R.; Rix, Hans-Walter +10 more

Theoretical models of stellar evolution predict that most of the lithium inside a star is destroyed as the star becomes a red giant. However, observations reveal that about 1% of red giants are peculiarly rich in lithium, often exceeding the amount in the interstellar medium or predicted from the big bang. With only about 150 lithium-rich giants d…

2019 The Astrophysical Journal
Gaia 84
A Mass-dependent Slope of the Galaxy Size-Mass Relation out to z ∼ 3: Further Evidence for a Direct Relation between Median Galaxy Size and Median Halo Mass
DOI: 10.3847/2041-8213/ab0379 Bibcode: 2019ApJ...872L..13M

Mowla, Lamiya; van Dokkum, Pieter; van der Wel, Arjen +1 more

We reassess the galaxy size-mass relation out to z ∼ 3 using a new definition of size and a sample of >29,000 galaxies from the 3D-HST, CANDELS, and COSMOS-DASH surveys. Instead of the half-light radius r 50 we use r 80, the radius containing 80% of the stellar light. We find that the r 80-M * relatio…

2019 The Astrophysical Journal
eHST 84
High Angular Resolution ALMA Images of Dust and Molecules in the SN 1987A Ejecta
DOI: 10.3847/1538-4357/ab4b46 Bibcode: 2019ApJ...886...51C

Bouchet, P.; Wheeler, J. C.; Matsuura, Mikako +23 more

We present high angular resolution (∼80 mas) ALMA continuum images of the SN 1987A system, together with CO J = 2 \to 1, J = 6 \to 5, and SiO J = 5 \to 4 to J = 7 \to 6 images, which clearly resolve the ejecta (dust continuum and molecules) and ring (synchrotron continuum) components. Dust in the ejecta is asymmetric and clumpy, and overall the du…

2019 The Astrophysical Journal
Herschel eHST 84