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Despite being the most common types of stars in the Galaxy, the physical properties of late M dwarfs are often poorly constrained. A trend of radius inflation compared to evolutionary models has been observed for earlier type M dwarfs in eclipsing binaries, possibly caused by magnetic activity. It is currently unclear whether this trend also extends to later type M dwarfs below the convective boundary. This makes the discovery of lower-mass, fully convective, M dwarfs in eclipsing binaries valuable for testing evolutionary models especially in longer-period binaries where tidal interaction between the primary and secondary is negligible. With this context, we present the discovery of the NGTS-EB-7 AB system, an eclipsing binary containing a late M dwarf secondary and an evolved G-type primary star. The secondary star has a radius of $0.125 \pm 0.006 R_\odot$ , a mass of $0.096 \pm 0.004 M_\odot$ and follows a highly eccentric $(e=0.71436 \pm 0.00085)$ orbit every $193.35875 \pm 0.00034$ days. This makes NGTS-EB-7 AB the third longest-period eclipsing binary system with a secondary smaller than $200 M_J$ with the mass and radius constrained to better than $5 \%$. In addition, NGTS-EB-7 is situated near the centre of the proposed LOPS2 southern field of the upcoming PLATO mission, allowing for detection of the secondary eclipse and measurement of the companion`s temperature. With its long-period and well-constrained physical properties - NGTS-EB-7 B will make a valuable addition to the sample of M dwarfs in eclipsing binaries and help in determining accurate empirical mass/radius relations for later M dwarf stars., Comment: Main body: 14 pages, 6 figures, 5 tables. Appendices: 7 pages, 5 figures, 5 tables

As noted by Heydenrych and Case (2017), tracing graduates using traditional survey method is known for its low response rate. In his study on the graduate destinations of chemical engineering in South Africa, he proposed the use of alternative methodology for similar research. To this date, only two studies have been confirmed to have used LinkedIn as the primary source of data for the employment information of chemical engineering graduates in the University of Cape Town (see Case, et al., 2013 and Heydenrych & Case, 2017). The purpose of this study is to determine the graduation destination of radiologic technology graduates from St. Jude College Dasmarinas, Cavite (SJCDC). The college had been offering a degree program for Bachelor of Science in Radiologic Technology (BSRT) since 2008, but there has been no tracer study conducted to determine the whereabouts of alumni in this program. This study follows the methodology of Heydenrych and Case (2017) who also used LinkedIn as the primary source of information about the destinations of graduates of chemical engineering in University of Cape Town. Results show that most radiologic technology graduates are currently employed in occupations that are aligned to their degree, suggesting that their undergraduate education prepares them for professional work in radiologic technology. Limitations were discussed and the conclusion attests to the usefulness of LinkedIn as an alternative source of information about the graduation destinations.

PLATO will begin observing stars in its Southern Field (LOPS2) after its launch in late 2026. By this time, TESS will have observed the stars in LOPS2 for at least four years. We find that by 2025, on average each star in the PLATO field will have been monitored for 330 days by TESS, with a subset of stars in the TESS continuous viewing zone having over 1000 days of monitoring. There are currently 101 known transiting exoplanets in the LOPS2 field, with 36 of these residing in multiplanet systems. The LOPS2 field also contains more than 500 TESS planet candidate systems, 64 exoplanets discovered by radial velocity only, over 1000 bright (V$<$13) eclipsing binary systems, 7 transiting brown dwarf systems, and 2 bright white dwarfs (G$<$13). We calculate TESS and PLATO sensitivities to detecting transits for the bright FGK stars that make up the PLATO LOPS2 P1 sample. We find that TESS should have discovered almost all transiting giant planets out to approximately 30 d within the LOPS2 field, and out to approximately 100 d for the regions of the LOPS2 field within the TESS CVZ ($\sim20$ per cent of the LOPS2 field). However, we find that for smaller radius planets in the range 1-4 R$_\oplus$ PLATO will have significantly better sensitivity, and these are likely to make up the bulk of new PLATO discoveries., Comment: 16 pages, 14 figures, accepted to MNRAS on 18 October 2024

The TESS mission has provided the community with high-precision times series photometry for $\sim$2.8 million stars across the entire sky via the Full Frame Image (FFI) light curves produced by the TESS Science Processing Operations Centre (SPOC). This set of light curves is an extremely valuable resource for the discovery of transiting exoplanets and other stellar science. However, due to the sample selection, this set of light curves does not constitute a magnitude limited sample. In order to understand the effects of this sample selection, we use Gaia DR2 and DR3 to study the properties of the stars in the TESS-SPOC FFI light curve set, with the aim of providing vital context for further research using the sample. We report on the properties of the TESS-SPOC FFI Targets in Sectors 1 - 55 (covering Cycles 1 - 4). We cross-match the TESS-SPOC FFI Targets with the Gaia DR2 and DR3 catalogues of all targets brighter than Gaia magnitude 14 to understand the effects of sample selection on the overall stellar properties. This includes Gaia magnitude, parallax, radius, temperature, non-single star flags, luminosity, radial velocity and stellar surface gravity. In total, there are $\sim$16.7 million Gaia targets brighter than G=14, which when cross-matched with the TESS-SPOC FFI Targets leaves $\sim$2.75 million. We investigate the binarity of each TESS-SPOC FFI Target and calculate the radius detection limit from two detected TESS transits which could be detected around each target. Finally, we create a comprehensive main sequence TESS-SPOC FFI Target sample which can be utilised in future studies., Comment: Accepted for publication in MNRAS. 12 pages, 13 figures, 2 tables

We present a study of the detection efficiency for the TESS mission, focusing on the yield of longer-period transiting exoplanets ($P > 25$ days). We created the Transit Investigation and Recoverability Application (TIaRA) pipeline to use real TESS data with injected transits to create sensitivity maps which we combine with occurrence rates derived from Kepler. This allows us to predict longer-period exoplanet yields, which will help design follow-up photometric and spectroscopic programs, such as the NGTS Monotransit Program. For the TESS Year 1 and Year 3 SPOC FFI lightucurves, we find $2271^{+241}_{-138}$ exoplanets should be detectable around AFGKM dwarf host stars. We find $215^{+37}_{-23}$ exoplanets should be detected from single-transit events or "monotransits". An additional $113^{+22}_{-13}$ detections should result from "biennial duotransit" events with one transit in Year 1 and a second in Year 3. We also find that K dwarf stars yield the most detections by TESS per star observed. When comparing our results to the TOI catalogue we find our predictions agree within $1\sigma$ of the number of discovered systems with periods between 0.78 and 6.25 days and agree to $2\sigma$ for periods between 6.25 and 2 days. Beyond periods of 25 days we predict $403^{+64}_{-38}$ detections, which is 3 times as many detections as there are in the TOI catalogue with $>3\sigma$ confidence. This indicates a significant number of long-period planets yet to be discovered from TESS data as monotransits or biennial duotransits., Comment: 17 pages, 16 figures. Accepted for Publication in Monthly Notices of the Royal Astronomical Society. Machine readable versions of sensitivity and yield grids available from: https://github.com/TobyRodel/TIaRA-TESS-Yields

Discovering transiting exoplanets with long orbital periods allows us to study warm and cool planetary systems with temperatures similar to the planets in our own Solar system. The TESS mission has photometrically surveyed the entire Southern Ecliptic Hemisphere in Cycle 1 (August 2018 - July 2019), Cycle 3 (July 2020 - June 2021) and Cycle 5 (September 2022 - September 2023). We use the observations from Cycle 1 and Cycle 3 to search for exoplanet systems that show a single transit event in each year - which we call duotransits. The periods of these planet candidates are typically in excess of 20 days, with the lower limit determined by the duration of individual TESS observations. We find 85 duotransit candidates, which span a range of host star brightnesses between 8 < $T_{mag}$ < 14, transit depths between 0.1 per cent and 1.8 per cent, and transit durations between 2 and 10 hours with the upper limit determined by our normalisation function. Of these candidates, 25 are already known, and 60 are new. We present these candidates along with the status of photometric and spectroscopic follow-up., Comment: 25 pages, 16 figures, submitted to Monthly Notices of the Royal Astronomical Society

Dynamics of the main dielectric anomaly in Na1/2Bi1/2TiO3 (NBT) was studied by time-domain THz and microwave spectroscopy, using also previously published data and their new overall fits. Above the dielectric maximum temperature Tm ~ 600 K, the response consists of coupled sub-THz oscillator and a relaxation mode, assigned to strongly anharmonic Bi-ion vibrations and hopping, whose slowing down explains the paraelectric-like permittivity increase to Tm. Below Tm, the main relaxation continues slowing down and additional relaxation, assigned to quasi-Debye losses, appears in the 10^11 Hz range. The oscillator hardens on cooling and takes over the whole oscillator strength. The permittivity decrease below Tm is caused by the reduced strength of the relaxations due to dominance of the rhombohedral phase within the coexistence region with the tetragonal phase. The anharmonic dynamics of Bi is supported by previous structural studies. NBT represents a hybrid between standard and relaxor ferroelectric behaviour.

We investigate the influence of a well-defined reversible biaxial strain <=0.12 % on the magnetization (M) of epitaxial ferromagnetic manganite films. M has been recorded depending on temperature, strain and magnetic field in 20 - 50 nm thick films. This is accomplished by reversibly compressing the isotropic in-plane lattice parameter of the rhombohedral piezoelectric 0.72PMN-0.28PT (001) substrates by application of an electric field E <= 12 kV cm-1. The magnitude of the total variable in-plane strain has been derived. Strain-induced shifts of the ferromagnetic Curie temperature (Tc) of up to 19 K were found in La0.7Sr0.3MnO3 (LSMO) and La0.7Ca0.3MnO3 films and are quantitatively analysed for LSMO within a cubic model. The observed large magnetoelectric coupling coefficient alpha=mu0 dM/dE <= 6 10-8 s m-1 at ambient temperature results from the strain-induced M change in the magnetic-film-ferroelectric-substrate system. It corresponds to an enhancement of mu0 DeltaM <= 19 mT upon biaxial compression of 0.1 %. The extraordinary large alpha originates from the combination of three crucial properties: (i) the strong strain dependence of M in the ferromagnetic manganites, (ii) large piezo-strain of the PMN-PT substrates and (iii) effective elastic coupling at the film-substrate interface., Comment: 15 pages, 6 figures, 1 table

Land surface models (LSMs) are computer programs, similar to weather and climate prediction models, which simulate the stocks and fluxes of water (including soil moisture, snow, evaporation, and runoff) and energy (including the temperature of and sensible heat released from the soil) after they arrive on the land surface as precipitation and sunlight. It is not currently possible to measure all of the variables of interest everywhere on Earth with sufficient accuracy and space-time resolution. Hence LSMs have been developed to integrate the available observations with our understanding of the physical processes involved, using powerful computers, in order to map these stocks and fluxes as they change in time. The maps are used to improve weather forecasts, support water resources and agricultural applications, and study the Earth's water cycle and climate variability. NASA's Global Land Data Assimilation System (GLDAS) project facilitates testing of several different LSMs with a variety of input datasets (e.g., precipitation, plant type). Precipitation is arguably the most important input to LSMs. Many precipitation datasets have been produced using satellite and rain gauge observations and weather forecast models. In this study, seven different global precipitation datasets were evaluated over the United States, where dense rain gauge networks contribute to reliable precipitation maps. We then used the seven datasets as inputs to GLDAS simulations, so that we could diagnose their impacts on output stocks and fluxes of water. In terms of totals, the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) had the closest agreement with the US rain gauge dataset for all seasons except winter. The CMAP precipitation was also the most closely correlated in time with the rain gauge data during spring, fall, and winter, while the satellitebased estimates performed best in summer. The GLDAS simulations revealed that modeled soil moisture is highly sensitive to precipitation, with differences in spring and summer as large as 45% depending on the choice of precipitation input.