Statistical Signatures of Nanoflare Activity. II. A Nanoflare Explanation for Periodic Brightenings in Flare Stars Observed by NGTS (2020)
Journal Article
(2020). Statistical Signatures of Nanoflare Activity. II. A Nanoflare Explanation for Periodic Brightenings in Flare Stars Observed by NGTS. Astrophysical Journal, 1-18. https://doi.org/10.3847/1538-4357/abbfa8

Several studies have documented periodic and quasi-periodic signals from the time series of dMe flare stars and other stellar sources. Such periodic signals, observed within quiescent phases (i.e., devoid of larger-scale microflare or flare activity)... Read More about Statistical Signatures of Nanoflare Activity. II. A Nanoflare Explanation for Periodic Brightenings in Flare Stars Observed by NGTS.

Wrinkling of a compressed hyperelastic half-space with localized surface imperfections (2020)
Journal Article
Fu. (2020). Wrinkling of a compressed hyperelastic half-space with localized surface imperfections. International Journal of Non-Linear Mechanics, https://doi.org/10.1016/j.ijnonlinmec.2020.103576

We consider a variant of the classical Biot problem concerning the wrinkling of a compressed hyperelastic half-space. The traction-free surface is no longer flat but has a localized ridge or trench that is invariant in the x1-direction along which th... Read More about Wrinkling of a compressed hyperelastic half-space with localized surface imperfections.

Rayleigh waves in micro-structured elastic systems: Non-reciprocity and energy symmetry breaking (2020)
Journal Article
Nieves, M., Carta, G., Pagneux, V., & Brun, M. (2020). Rayleigh waves in micro-structured elastic systems: Non-reciprocity and energy symmetry breaking. International Journal of Engineering Science, https://doi.org/10.1016/j.ijengsci.2020.103365

Rayleigh waves are analysed in elastic lattices incorporating inertial devices that couple in-plane displacements. The vector problems of elasticity for a triangular lattice and its long-wavelength/low-frequency continuum approximation are considered... Read More about Rayleigh waves in micro-structured elastic systems: Non-reciprocity and energy symmetry breaking.

NGTS-12b: A sub-Saturn mass transiting exoplanet in a 7.53 day orbit (2020)
Journal Article
(2020). NGTS-12b: A sub-Saturn mass transiting exoplanet in a 7.53 day orbit. Monthly Notices of the Royal Astronomical Society, 3139 - 3148. https://doi.org/10.1093/mnras/staa2976

We report the discovery of the transiting exoplanet NGTS-12b by the Next Generation Transit Survey (NGTS). The host star, NGTS-12, is a V = 12.38?mag star with an effective temperature of Teff = 5690 ± 130?K. NGTS-12b orbits with a period of P = 7.53... Read More about NGTS-12b: A sub-Saturn mass transiting exoplanet in a 7.53 day orbit.

Constraining the thermally pulsing asymptotic giant branch phase with resolved stellar populations in the Large Magellanic Cloud (2020)
Journal Article
Van Loon. (2020). Constraining the thermally pulsing asymptotic giant branch phase with resolved stellar populations in the Large Magellanic Cloud. Monthly Notices of the Royal Astronomical Society, 3283-3301. https://doi.org/10.1093/mnras/staa2565

Reliable models of the thermally pulsing asymptotic giant branch (TP-AGB) phase are of critical importance across astrophysics, including our interpretation of the spectral energy distribution of galaxies, cosmic dust production, and enrichment of th... Read More about Constraining the thermally pulsing asymptotic giant branch phase with resolved stellar populations in the Large Magellanic Cloud.

The TOI-763 system: sub-Neptunes orbiting a Sun-like star (2020)
Journal Article
Hellier. (2020). The TOI-763 system: sub-Neptunes orbiting a Sun-like star. Monthly Notices of the Royal Astronomical Society, 4503-4517. https://doi.org/10.1093/mnras/staa2502

We report the discovery of a planetary system orbiting TOI-763 (aka CD-39 7945), a V = 10.2, high proper motion G-type dwarf star that was photometrically monitored by the TESS space mission in Sector 10. We obtain and model the stellar spectrum and... Read More about The TOI-763 system: sub-Neptunes orbiting a Sun-like star.

A white dwarf bound to the transiting planetary system WASP-98 (2020)
Journal Article
Southworth, J., Tremblay, P., Gänsicke, B. T., Evans, D., & Močnik, T. (2020). A white dwarf bound to the transiting planetary system WASP-98. Monthly Notices of the Royal Astronomical Society, 497(4), 4416 - 4422. https://doi.org/10.1093/mnras/staa2328

WASP-98 is a planetary system containing a hot Jupiter transiting a late-G dwarf. A fainter star 12? distant has previously been identified as a white dwarf, with a distance and proper motion consistent with a physical association with the planetary... Read More about A white dwarf bound to the transiting planetary system WASP-98.

The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity (2020)
Journal Article
Jeffries, R., & Wright, N. J. (2020). The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity. Astronomy and Astrophysics, https://doi.org/10.1051/0004-6361/202038688

Context. Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced prod... Read More about The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity.

Fundamental effective temperature measurements for eclipsing binary stars I. Development of the method and application to AI Phoenicis (2020)
Journal Article
Smalley, & Maxted. (2020). Fundamental effective temperature measurements for eclipsing binary stars I. Development of the method and application to AI Phoenicis. Monthly Notices of the Royal Astronomical Society, 2899-2909. https://doi.org/10.1093/mnras/staa2167

Stars with accurate and precise effective temperature (Teff) measurements are needed to test stellar atmosphere models and calibrate empirical methods to determine Teff. There are few standard stars currently available to calibrate temperature indica... Read More about Fundamental effective temperature measurements for eclipsing binary stars I. Development of the method and application to AI Phoenicis.

The Compact Triply Eclipsing Triple Star TIC 209409435 Discovered with TESS (2020)
Journal Article
Maxted. (2020). The Compact Triply Eclipsing Triple Star TIC 209409435 Discovered with TESS. Monthly Notices of the Royal Astronomical Society, 4624-4636. https://doi.org/10.1093/mnras/staa1817

We report the discovery in TESS Sectors 3 and 4 of a compact triply eclipsing triple star system. TIC 209409435 is a previously unknown eclipsing binary with a period of 5.717 days, and the presence of a third star in an outer eccentric orbit of 121.... Read More about The Compact Triply Eclipsing Triple Star TIC 209409435 Discovered with TESS.

The VMC survey – XXXIX: Mapping metallicity trends in the Small Magellanic Cloud using near-infrared passbands (2020)
Journal Article
Choudhury, S., de Grijs, R., Rubele, S., Bekki, K., Cioni, M.-R. L., Ivanov, V. D., Van Loon, J. T., Niederhofer, F., Oliveira, J. M., & Ripepi, V. (2020). The VMC survey – XXXIX: Mapping metallicity trends in the Small Magellanic Cloud using near-infrared passbands. Monthly Notices of the Royal Astronomical Society, 497(3), 3746-3760. https://doi.org/10.1093/mnras/staa2140

We have derived high spatial resolution metallicity maps covering ~42 deg2 across the Small Magellanic Cloud (SMC) in an attempt to understand its metallicity distribution and gradients up to a radius of ~ 4?. Using the near-infrared VISTA Survey of... Read More about The VMC survey – XXXIX: Mapping metallicity trends in the Small Magellanic Cloud using near-infrared passbands.

Two Directly Imaged, Wide-orbit Giant Planets around the Young, Solar Analog TYC 8998-760-1 (2020)
Journal Article
Bohn, A. J., Kenworthy, M. A., Ginski, C., Rieder, S., Mamajek, E. E., Meshkat, T., Pecaut, M. J., Reggiani, M., de Boer, J., Keller, C. U., Snik, F., & Southworth, J. (2020). Two Directly Imaged, Wide-orbit Giant Planets around the Young, Solar Analog TYC 8998-760-1. Astrophysical Journal, 898, Article L16. https://doi.org/10.3847/2041-8213/aba27e

Even though tens of directly imaged companions have been discovered in the past decades, the number of directly confirmed multiplanet systems is still small. Dynamical analysis of these systems imposes important constraints on formation mechanisms of... Read More about Two Directly Imaged, Wide-orbit Giant Planets around the Young, Solar Analog TYC 8998-760-1.

The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc (2020)
Journal Article
Jeffries. (2020). The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202038055

Context. In the era of large spectroscopic surveys, massive databases of high-quality spectra coupled with the products of the Gaia satellite provide tools to outline a new picture of our Galaxy. In this framework, an important piece of information i... Read More about The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc.

The Gaia-ESO Survey: Membership probabilities for stars in 32 open clusters from 3D kinematics (2020)
Journal Article
Jeffries, & Wright. (2020). The Gaia-ESO Survey: Membership probabilities for stars in 32 open clusters from 3D kinematics. Monthly Notices of the Royal Astronomical Society, 4701-4716. https://doi.org/10.1093/mnras/staa1749

The Gaia-ESO Survey (GES) observed many open clusters as part of its programme to spectroscopically characterise the various Milky Way populations. GES spectroscopy and Gaia astrometry from its second data release are used here to assign membership p... Read More about The Gaia-ESO Survey: Membership probabilities for stars in 32 open clusters from 3D kinematics.

Relative Importance of Convective Uncertainties in Massive Stars (2020)
Journal Article
Kaiser, E. A., Hirschi, R., Arnett, W. D., Georgy, C., Scott, L. J. A., & Cristini, A. (2020). Relative Importance of Convective Uncertainties in Massive Stars. Monthly Notices of the Royal Astronomical Society, 496(2), 1967-1989. https://doi.org/10.1093/mnras/staa1595

In this work, we investigate the impact of uncertainties due to convective boundary mixing (CBM), commonly called ‘overshoot’, namely the boundary location and the amount of mixing at the convective boundary, on stellar structure and evolution. For t... Read More about Relative Importance of Convective Uncertainties in Massive Stars.

Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3 (2020)
Journal Article
Jackson. (2020). Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3. Crystals, https://doi.org/10.3390/cryst10060457

The doping of LiNbO(3)with V2+, V3+, V(4+)and V(5+)as well as Mo3+, Mo4+, Mo(5+)and Mo(6+)ions is of interest in enhancing its photorefractive properties. In this paper, possible incorporation mechanisms for these ions in LiNbO(3)are modelled, using... Read More about Computer Simulation of the Incorporation of V2+, V3+, V4+, V(5+)and Mo3+, Mo4+, Mo5+, Mo(6+)Dopants in LiNbO3.

Black hole inconsistencies? (2020)
Preprint / Working Paper
Austin, J. Black hole inconsistencies?

For large enough astrophysical objects, internal pressures are insufficient to prevent gravitational collapse to sizes smaller than a critical radius where the magnitude of escape velocity is equal to the speed of light. In coordinates natural for di... Read More about Black hole inconsistencies?.

Discovery of ß Cep pulsations in the eclipsing binary V453 Cygni (2020)
Journal Article
Southworth, J., Bowman, D. M., Tkachenko, A., & Pavlovski, K. (2020). Discovery of ß Cep pulsations in the eclipsing binary V453 Cygni. Monthly Notices of the Royal Astronomical Society: Letters, 497(1), L19–L23. https://doi.org/10.1093/mnrasl/slaa091

V453 Cyg is an eclipsing binary containing 14 and 11 $\, \rm M_ødot$ stars in an eccentric short-period orbit. We have discovered ß Cep-type pulsations in this system using Transiting Exoplanet Survey Satellite data. We identify seven significant pul... Read More about Discovery of ß Cep pulsations in the eclipsing binary V453 Cygni.

Brouwer’s Weak Counterexamples and the Creative Subject: A Critical Survey (2020)
Journal Article
Fletcher. (2020). Brouwer’s Weak Counterexamples and the Creative Subject: A Critical Survey. Journal of Philosophical Logic, 49, 1111-1157. https://doi.org/10.1007/s10992-020-09551-y

I survey Brouwer’s weak counterexamples to classical theorems, with a view to discovering (i) what useful mathematical work is done by weak counterexamples; (ii) whether they are rigorous mathematical proofs or just plausibility arguments; (iii) the... Read More about Brouwer’s Weak Counterexamples and the Creative Subject: A Critical Survey.

Boundary layer collapses described by the two-dimensional intermediate long-wave equation (2020)
Journal Article
Oloo, J., & Shrira, V. (2020). Boundary layer collapses described by the two-dimensional intermediate long-wave equation. Theoretical and Mathematical Physics, 203, 512 - 523. https://doi.org/10.1134/S0040577920040078

We study the nonlinear dynamics of localized perturbations of a confined generic boundary-layer shear flow in the framework of the essentially two-dimensional generalization of the intermediate long-wave (2d-ILW) equation. The 2d-ILW equation was ori... Read More about Boundary layer collapses described by the two-dimensional intermediate long-wave equation.