Search Publications
Relative Crater Scaling Between the Major Moons of Saturn: Implications for Planetocentric Cratering and the Surface Age of Titan
Bell, Samuel W.
The chronology of the moons of Saturn, especially Titan, has been limited by a lack of strong constraints on the cratering rate, low number statistics for small-N counts of large-diameter craters, and uncertainty about whether impactors are mostly heliocentric impactors orbiting the Sun or planetocentric impactors orbiting Saturn itself. Here, I p…
A New Microquasar Candidate in M83
Soria, Roberto; Blair, William P.; Long, Knox S. +2 more
Microquasars are neutron star or black hole X-ray binaries with jets. These jets can create bubbles of hot plasma shock ionized that can masquerade as peculiar supernova remnants (SNRs) in extragalactic surveys. To see if this is the case in the well-studied spiral galaxy M83, where one microquasar candidate (M83-MQ1) has already been identified, …
Transit least-squares survey. III. A 1.9 R⊕ transit candidate in the habitable zone of Kepler-160 and a nontransiting planet characterized by transit-timing variations
Batalha, Natalie M.; Bryson, Steve; Heller, René +3 more
The Sun-like star Kepler-160 (KOI-456) has been known to host two transiting planets, Kepler-160 b and c, of which planet c shows substantial transit-timing variations (TTVs). We studied the transit photometry and the TTVs of this system in our search for a suspected third planet. We used the archival Kepler photometry of Kepler-160 to search for …
GJ 357 b. A super-Earth orbiting an extremely inactive host star
Güdel, M.; Sanz-Forcada, J.; Maldonado, J. +5 more
Aims: In this paper we present a deep X-ray observation of the nearby M dwarf GJ 357 and use it to put constraints on the atmospheric evolution of its planet, GJ 357 b. We also analyse the systematic errors in the stellar parameters of GJ 357 in order to see how they affect the perceived planetary properties.
Methods: By comparing the ob…
The first Doppler imaging of the active binary prototype RS Canum Venaticorum
Schmitt, J. H. M. M.; Wolter, U.; Collier Cameron, A. +6 more
We present the first Doppler images of the prototypical active binary star RS Canum Venaticorum, derived from high-resolution spectra observed in 2004, 2016 and 2017, using three different telescopes and observing sites. We apply the least-squares deconvolution technique to all observed spectra to obtain high signal-to-noise line profiles, which a…
A distinct magnetic property of the inner penumbral boundary. III. Analysis of simulated sunspots
Rempel, Matthias; Jurčák, Jan; Schmassmann, Markus +2 more
Context. Analyses of sunspot observations revealed a fundamental magnetic property of the umbral boundary: the invariance of the vertical component of the magnetic field.
Aims: We analyse the magnetic properties of the umbra-penumbra boundary in simulated sunspots and thus assess their similarity to observed sunspots. We also aim to investiga…
Type IIP Supernova Progenitors. II. Stellar Mass and Obscuration by the Dust in the Circumstellar Medium
Ray, Alak; Wagle, Gururaj A.
It has been well established from a variety of observations that red supergiants (RSGs) lose a lot of mass in stellar wind. Dust that has formed in this emitted gas over a few decades before core-collapse can lead to substantial extinction and obscure the intrinsic luminosity of the progenitor RSG. This may lead to a difficulty in determining the …
Determination of Size, Albedo, and Thermal Inertia of 10 Vesta Family Asteroids with WISE/NEOWISE Observations
Ji, Jianghui; Jiang, Haoxuan; Yu, Liangliang
In this work, we investigate the size, thermal inertia, surface roughness, and geometric albedo of 10 Vesta family asteroids using the Advanced Thermophysical Model, based on the thermal-infrared data acquired by mainly NASA's Wide-field Infrared Survey Explorer. Here, we show that the average thermal inertia and geometric albedo of the investigat…
High-Resolution Radio Observations of Five Optically Selected Type 2 Quasars
Paragi, Zsolt; Krezinger, Máté; Frey, Sándor +1 more
Many low-luminosity active galactic nuclei (AGNs) contain a compact radio core which can be observed with high angular resolution using very long baseline interferometry (VLBI). Combining arcsec-scale structural information with milliarcsec-resolution VLBI imaging is a useful way to characterise the objects and to find compact cores on parsec scal…
ESPRESSO highlights the binary nature of the ultra-metal-poor giant HE 0107-5240
Rebolo, R.; Allende Prieto, C.; Bonifacio, P. +29 more
Context. The vast majority of the known stars of ultra low metallicity ([Fe/H] < -4.5) are known to be enhanced in carbon, and belong to the "low-carbon band" (A(C) = log(C/H)+12 ≤ 7.6). It is generally, although not universally, accepted that this peculiar chemical composition reflects the chemical composition of the gas cloud out of which the…