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Uncertainties in s -process nucleosynthesis in low mass stars determined from Monte Carlo variations (2018)
Journal Article
Cescutti, G., Hirschi, R., Nishimura, N., den Hartogh, J. W., Rauscher, T., Murphy, A. S. J., & Cristallo, S. (2018). Uncertainties in s -process nucleosynthesis in low mass stars determined from Monte Carlo variations. Monthly Notices of the Royal Astronomical Society, 478(3), 4101-4127. https://doi.org/10.1093/mnras/sty1185

The main s-process taking place in low mass stars produces about half of the elements heavier than iron. It is therefore very important to determine the importance and impact of nuclear physics uncertainties on this process. We have performed extensi... Read More about Uncertainties in s -process nucleosynthesis in low mass stars determined from Monte Carlo variations.

The VMC Survey. XXIX. Turbulence-controlled Hierarchical Star Formation in the Small Magellanic Cloud (2018)
Journal Article
Van Loon, J., & Oliveira, J. (2018). The VMC Survey. XXIX. Turbulence-controlled Hierarchical Star Formation in the Small Magellanic Cloud. Astrophysical Journal, https://doi.org/10.3847/1538-4357/aabc50

In this paper we report a clustering analysis of upper main-sequence stars in the Small Magellanic Cloud, using data from the VMC survey (the VISTA near-infrared YJK s survey of the Magellanic system). Young stellar structures are identified as surfa... Read More about The VMC Survey. XXIX. Turbulence-controlled Hierarchical Star Formation in the Small Magellanic Cloud.

Helium in the eroding atmosphere of an exoplanet (2018)
Journal Article
Hellier. (2018). Helium in the eroding atmosphere of an exoplanet. Nature, 68 -70. https://doi.org/10.1038/s41586-018-0067-5

Helium is the second-most abundant element in the Universe after hydrogen and is one of the main constituents of gas-giant planets in our Solar System. Early theoretical models predicted helium to be among the most readily detectable species in the a... Read More about Helium in the eroding atmosphere of an exoplanet.

The Kinematics of the Scorpius-Centaurus OB Association from Gaia DR1 (2018)
Journal Article
Wright. (2018). The Kinematics of the Scorpius-Centaurus OB Association from Gaia DR1. Monthly Notices of the Royal Astronomical Society, 381-398. https://doi.org/10.1093/mnras/sty207

We present a kinematic study of the Scorpius-Centaurus (Sco-Cen) OB association (Sco OB2) using Gaia DR1 parallaxes and proper motions. Our goal is to test the classical theory that OB associations are the expanded remnants of dense and compact star... Read More about The Kinematics of the Scorpius-Centaurus OB Association from Gaia DR1.

On the nature of the high-energy rollover in 1H 0419-577 (2018)
Journal Article
(2018). On the nature of the high-energy rollover in 1H 0419-577. Monthly Notices of the Royal Astronomical Society, 1258 -1270. https://doi.org/10.1093/mnras/sty318

A NuSTAR/Swift observation of the luminous Seyfert 1 galaxy 1H 0419-577 taken during 2015 reveals one of the most extreme high-energy cut-offs observed to date from an AGN – an origin due to thermal Comptonization would imply a remarkably low coronal... Read More about On the nature of the high-energy rollover in 1H 0419-577.

Suppressed phase variations in a high amplitude rapidly oscillating Ap star pulsating in a distorted quadrupole mode (2018)
Journal Article
Holdsworth, D., Saio, H., Bowman, D., Kurtz, D., Lambert, T., Smalley, B., Joyce, M., & Sefako, R. (2018). Suppressed phase variations in a high amplitude rapidly oscillating Ap star pulsating in a distorted quadrupole mode. Monthly Notices of the Royal Astronomical Society, 601-616. https://doi.org/10.1093/mnras/sty248

We present the results of a multisite photometric observing campaign on the rapidly oscillating Ap (roAp) star 2MASS 16400299-0737293 (J1640; $V=12.7$). We analyse photometric $B$ data to show the star pulsates at a frequency of $151.93$ d$^{-1}$ ($1... Read More about Suppressed phase variations in a high amplitude rapidly oscillating Ap star pulsating in a distorted quadrupole mode.

Oscillating red giants in eclipsing binary systems: empirical reference value for asteroseismic scaling relation (2018)
Journal Article
Themeßl, N., Hekker, S., Southworth, J., Beck, P. G., Pavlovski, K., Tkachenko, A., Angelou, G. C., Ball, W. H., Barban, C., Corsaro, E., Elsworth, Y., Handberg, R., & Kallinger, T. (2018). Oscillating red giants in eclipsing binary systems: empirical reference value for asteroseismic scaling relation. Monthly Notices of the Royal Astronomical Society, 478(4), 4669 -4696. https://doi.org/10.1093/mnras/sty1113

Based on 1460?d of Kepler observations we perform a thorough asteroseismic study to probe the stellar parameters and evolutionary stages of three red giants in eclipsing binary systems. We present the first detailed analysis of individual oscillation... Read More about Oscillating red giants in eclipsing binary systems: empirical reference value for asteroseismic scaling relation.

The Gaia-ESO Survey: open clusters in Gaia-DR1. A way forward to stellar age calibration (2018)
Journal Article
Randich, S., Tognelli, E., Jackson, R., Jeffries, R., Degl’Innocenti, S., Pancino, E., Re Fiorentin, P., Spagna, A., Sacco, G., Bragaglia, A., Magrini, L., Prada Moroni, P., Alfaro, E., Franciosini, E., Morbidelli, L., Roccatagliata, V., Bouy, H., Bravi, L., Jiménez-Esteban, F., Jordi, C., …Zaggia, S. (2018). The Gaia-ESO Survey: open clusters in Gaia-DR1. A way forward to stellar age calibration. Astronomy and Astrophysics, 612, Article A99. https://doi.org/10.1051/0004-6361/201731738

Context
Determination and calibration of the ages of stars, which heavily rely on stellar evolutionary models, are very challenging, while representing a crucial aspect in many astrophysical areas.

Aims
We describe the methodologies that, taking... Read More about The Gaia-ESO Survey: open clusters in Gaia-DR1. A way forward to stellar age calibration.

Discovery of a New Classical Nova Shell Around a Nova-like Cataclysmic Variable (2018)
Journal Article
Wright. (2018). Discovery of a New Classical Nova Shell Around a Nova-like Cataclysmic Variable. Astrophysical Journal, https://doi.org/10.3847/1538-4357/aab669

The morphology and optical spectrum of IPHASX J210204.7+471015, a nebula classified as a possible planetary
nebula are, however, strikingly similar to those of AT Cnc, a classical nova shell around a dwarf nova. To
investigate its true nature, we h... Read More about Discovery of a New Classical Nova Shell Around a Nova-like Cataclysmic Variable.

A new mechanical stellar wind feedback model for the Rosette Nebula (2018)
Journal Article
Wright. (2018). A new mechanical stellar wind feedback model for the Rosette Nebula. Monthly Notices of the Royal Astronomical Society, 3598-3612. https://doi.org/10.1093/mnras/sty148

The famous Rosette Nebula has an evacuated central cavity formed from the stellar winds ejected from the 2-6 million-year-old co-distant and co-moving central star cluster NGC 2244. However, with upper age estimates of less than 110,000 years, the ce... Read More about A new mechanical stellar wind feedback model for the Rosette Nebula.

A and F stars as probes of outer Galactic disc kinematics (2018)
Journal Article
Wright. (2018). A and F stars as probes of outer Galactic disc kinematics. Monthly Notices of the Royal Astronomical Society, 1680 -1695. https://doi.org/10.1093/mnras/stx3299

Previous studies of the rotation law in the outer Galactic disc have mainly used gas tracers or clump giants. Here, we explore A and F stars as alternatives: these provide a much denser sampling in the outer disc than gas tracers and have experienced... Read More about A and F stars as probes of outer Galactic disc kinematics.

The discovery of WASP-151b, WASP-153b, WASP-156b: Insights on giant planet migration and the upper boundary of the Neptunian desert (2018)
Journal Article
Smalley, Hellier, & Maxted. (2018). The discovery of WASP-151b, WASP-153b, WASP-156b: Insights on giant planet migration and the upper boundary of the Neptunian desert. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/201731735

To investigate the origin of the features discovered in the exoplanet population, the knowledge of exoplanets mass and radius with a good precision (less than or similar to 10%) is essential. To achieve this purpose the discovery of transiting exopla... Read More about The discovery of WASP-151b, WASP-153b, WASP-156b: Insights on giant planet migration and the upper boundary of the Neptunian desert.

OGLE-2017-BLG-1434Lb: Eighth q < 1 x 10(-4) Mass-Ratio Microlens Planet Confirms Turnover in Planet Mass-Ratio Function (2018)
Journal Article
Udalski, A., Ryu, Y.-H., Sajadian, S., Gould, A., Mróz, P., Poleski, R., Szymański, M., Skowron, J., Soszyński, I., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Pawlak, M., Rybicki, K., Iwanek, P., Albrow, M., Chung, S.-J., Han, C., Hwang, K.-H., Jung, Y., …von Essen, C. (2018). OGLE-2017-BLG-1434Lb: Eighth q < 1 x 10(-4) Mass-Ratio Microlens Planet Confirms Turnover in Planet Mass-Ratio Function. Acta Astronomica, 68(1), 1 -42. https://doi.org/10.32023/0001-5237/68.1.1

We report the discovery of a cold Super-Earth planet (m(p) = 4.4 +/- 0.5 M-circle plus) orbiting a low-mass (M = 0.23 +/- 0.03 M-circle dot) M dwarf at projected separation a(perpendicular to) l = 1.18 +/- 0.10 a.u., i.e., about 1.9 times the distanc... Read More about OGLE-2017-BLG-1434Lb: Eighth q < 1 x 10(-4) Mass-Ratio Microlens Planet Confirms Turnover in Planet Mass-Ratio Function.

High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP). II. Lucky Imaging results from 2015 and 2016 (2018)
Journal Article
Evans, D., Southworth, J., Smalley, B., Jørgensen, U., Dominik, M., Andersen, M., Bozza, V., Bramich, D., Burgdorf, M., Ciceri, S., D’Ago, G., Figuera Jaimes, R., Gu, S.-H., Hinse, T., Henning, T., Hundertmark, M., Kains, N., Kerins, E., Korhonen, H., Kokotanekova, R., …Wertz, O. (2018). High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP). II. Lucky Imaging results from 2015 and 2016. Astronomy and Astrophysics, 610, Article A20. https://doi.org/10.1051/0004-6361/201731855

Context.
The formation and dynamical history of hot Jupiters is currently debated, with wide stellar binaries having been suggested as a potential formation pathway. Additionally, contaminating light from both binary companions and unassociated star... Read More about High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP). II. Lucky Imaging results from 2015 and 2016.

Using principal component analysis to understand the variability of PDS 456 (2018)
Journal Article
(2018). Using principal component analysis to understand the variability of PDS 456. Monthly Notices of the Royal Astronomical Society, 108 - 114. https://doi.org/10.1093/mnras/stx2803

We present a spectral-variability analysis of the low-redshift quasar PDS 456 using principal component analysis. In the XMM–Newton data, we find a strong peak in the first principal component at the energy of the Fe absorption line from the highly b... Read More about Using principal component analysis to understand the variability of PDS 456.

Using principal component analysis to understand the variability of PDS 456 (2018)
Journal Article
(2018). Using principal component analysis to understand the variability of PDS 456. Monthly Notices of the Royal Astronomical Society, 108-114. https://doi.org/10.1093/mnras/stx2803

We present a spectral-variability analysis of the low-redshift quasar PDS 456 using principal component analysis. In the XMM-Newton data, we find a strong peak in the first principal component at the energy of the Fe absorption line from the highly b... Read More about Using principal component analysis to understand the variability of PDS 456.

Evolutionary Constraints on the Long-period Subdwarf B Binary PG 1018–047 (2018)
Journal Article
Maxted. (2018). Evolutionary Constraints on the Long-period Subdwarf B Binary PG 1018–047. Monthly Notices of the Royal Astronomical Society, 1018-1047. https://doi.org/10.1093/mnras/stx2755

We have revisited the sdB+K-star long-period binary PG 1018–047 based on 20 new high-resolution VLT/UVES spectra that provided regular coverage over a period of more than 26 months. We refine the period and establish that the orbit is significantly e... Read More about Evolutionary Constraints on the Long-period Subdwarf B Binary PG 1018–047.

The Variable Fast Soft X-Ray Wind in PG 1211+143 (2018)
Journal Article
(2018). The Variable Fast Soft X-Ray Wind in PG 1211+143. Astrophysical Journal, 28 - ?. https://doi.org/10.3847/1538-4357/aaa776

The analysis of a series of seven observations of the nearby ( z = 0.0809) QSO PG 1211+143, taken with the Reflection Grating Spectrometer (RGS) onboard XMM-Newton in 2014, are presented. The high-resolution soft X-ray spectrum, with a total exposure... Read More about The Variable Fast Soft X-Ray Wind in PG 1211+143.

A New Relativistic Component of the Accretion Disk Wind in PDS 456 (2018)
Journal Article
(2018). A New Relativistic Component of the Accretion Disk Wind in PDS 456. Astrophysical Journal Letters, L8 -?. https://doi.org/10.3847/2041-8213/aaaae1

Past X-ray observations of the nearby luminous quasar PDS 456 (at z = 0.184) have revealed a wide angle accretion disk wind, with an outflow velocity of ~-0.25 c . Here, we unveil a new, relativistic component of the wind through hard X-ray observati... Read More about A New Relativistic Component of the Accretion Disk Wind in PDS 456.