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Abstract Introduction The association between chronic pain and frailty might indicate that pain is an independent driver of frailty but might alternatively be explained by inclusion within frailty identification tools of morbidities that commonly lead to chronic pain. This research examines the extent to which the association of pain with frailty might be attributed to morbidities. Methods A cross-sectional analysis of older people in a UK cohort with or at risk of musculoskeletal problems or frailty (Investigating Musculoskeletal Health and Wellbeing study), used multivariable logistic regression and Z-tests to assess the degrees of associations of pain (McGill Pain Rating Index), and painful and non-painful morbidity counts with frailty (modified FRAIL questionnaire). Results Data were from 2,185 participants, 56% female, median age 73 (range 60 to 96) years. 430 (20%) participants were classified as frail. In a fully adjusted standardised model, pain (aOR 2.07 (95%CI 1.83 to 2.33) and ‘any’ morbidity aOR (1.74 (95%CI 1.54 to 1.97) were both significantly associated with frailty. When morbidity was subclassified as painful or non-painful, painful (aOR 1.48 (95%CI 1.30 to 1.68) and non-painful (aOR1.39 (95%CI 1.24 to 1.56)) morbidities each were associated with frailty, as also was pain (aOR 2.07 (95%CI 1.83 to 2.34, p

Theory predicts a deficit of super-Earth sized planets, which orbit close to their host star. Here, Lundkvist et al. use data from the NASA Kepler mission to show that this deficit is also seen in observations, thereby providing new insight into exoplanetary systems.

Resonance scattering techniques are often used to study the properties of atoms and molecules. The Birmingham Solar Oscillations Network (BiSON) makes use of Resonance Scattering Spectroscopy by applying the known properties of potassium vapour to achieve ultra-precise Doppler velocity observations of oscillations of the Sun. We present a model of the resonance scattering properties of potassium vapour which can be used to determine the ideal operating vapour temperature and detector parameters within a spectrophotometer. The model is validated against a typical BiSON vapour cell using a tunable diode laser, where the model is fitted to observed absorption profiles at a range of temperatures. Finally we demonstrate using the model to determine the effects of varying scattering detector aperture size, and vapour temperature, and again validate against observed scattering profiles. Such information is essential when designing the next generation of BiSON spectrophotometers (BiSON:NG), where the aim is to make use of off-the-shelf components to simplify and miniaturise the instrumentation as much as practical. [ABSTRACT FROM AUTHOR]

In the Sun, the properties of acoustic modes are sensitive to changes in the magnetic activity. In particular, mode frequencies are observed to increase with increasing activity level. Thanks to CoRoT and Kepler, such variations have been found in other solar-type stars and encode information on the activity-related changes in their interiors. Thus, the unprecedented long-term Kepler photometric observations provide a unique opportunity to study stellar activity through asteroseismology. The goal of this work is to investigate the dependencies of the observed mode frequency variations on the stellar parameters and whether those are consistent with an activity-related origin. We select the solar-type oscillators with highest signal-to-noise ratio, in total, 75 targets. Using the temporal frequency variations determined in Santos et al., we study the relation between those variations and the fundamental stellar properties. We also compare the observed frequency shifts with chromospheric and photometric activity indexes, which are only available for a subset of the sample. We find that frequency shifts increase with increasing chromospheric activity, which is consistent with an activity-related origin of the observed frequency shifts. Frequency shifts are also found to increase with effective temperature, which is in agreement with the theoretical predictions for the activity-related frequency shifts by Metcalfe et al. Frequency shifts are largest for fast rotating and young stars, which is consistent with those being more active than slower rotators and older stars. Finally, we find evidence for frequency shifts increasing with stellar metallicity. [ABSTRACT FROM AUTHOR]

Manifestations of stellar activity (such as star-spots, plage/faculae, and convective flows) are well-known to induce spectroscopic signals often referred to as astrophysical noise by exoplanet hunters. For example, setting an ultimate goal of detecting true Earth analogs demands reaching radial velocity (RV) precisions of ∼9 cm s−1. While this is becoming technically feasible with the latest generation of highly stabilized spectrographs, it is astrophysical noise that sets the true fundamental barrier on attainable RV precisions. In this paper, we parameterize the impact of solar surface magneto-convection on absorption line profiles, and extend the analysis from the solar disk center (Paper I) to the solar limb. Off disk-center, the plasma flows orthogonal to the granule tops begin to lie along the line of sight, and those parallel to the granule tops are no longer completely aligned with the observer. Moreover, the granulation is corrugated and the granules can block other granules, as well as the intergranular lane components. Overall, the visible plasma flows and geometry of the corrugated surface significantly impact the resultant line profiles and induce center-to-limb variations in shape and net position. We detail these herein, and compare to various solar observations. We find our granulation parameterization can recreate realistic line profiles and induced radial velocity shifts, across the stellar disk, indicative of both those found in computationally heavy radiative 3D magnetohydrodynamical simulations and empirical solar observations. [ABSTRACT FROM AUTHOR]

We report the first asteroseismic results obtained with the Hertzsprung Stellar Observations Network Group Telescope from an extensive high-precision radial-velocity observing campaign of the subgiant μ Herculis. The data set was collected during 215 nights in 2014 and 2015. We detected a total of 49 oscillation modes with l values from zero to three, including some l = 1 mixed modes. Based on the rotational splitting observed in l = 1 modes, we determine a rotational period of 52 days and a stellar inclination angle of 63°. The parameters obtained through modeling of the observed oscillation frequencies agree very well with independent observations and imply a stellar mass between 1.11 and 1.15 M⊙ and an age of Gyr. Furthermore, the high-quality data allowed us to determine the acoustic depths of the He ii ionization layer and the base of the convection zone. [ABSTRACT FROM AUTHOR]

θ Cygni is an F3 spectral type magnitude V = 4.48 main-sequence star that was the brightest star observed by the original Kepler spacecraft mission. Short-cadence (58.8 s) photometric data using a custom aperture were first obtained during Quarter 6 (2010 June–September) and subsequently in Quarters 8 and 12–17. We present analyses of solar-like oscillations based on Q6 and Q8 data, identifying angular degree l = 0, 1, and 2 modes with frequencies of 1000–2700 μHz, a large frequency separation of 83.9 ± 0.4 μHz, and maximum oscillation amplitude at frequency νmax = 1829 ± 54 μHz. We also present analyses of new ground-based spectroscopic observations, which, combined with interferometric angular diameter measurements, give Teff = 6697 ± 78 K, radius 1.49 ± 0.03 R⊙, [Fe/H] = −0.02 ± 0.06 dex, and log g = 4.23 ± 0.03. We calculate stellar models matching these constraints using the Yale Rotating Evolution Code and the Asteroseismic Modeling Portal. The best-fit models have masses of 1.35–1.39 M⊙ and ages of 1.0–1.6 Gyr. θ Cyg’s Teff and log g place it cooler than the red edge of the γ Doradus instability region established from pre-Kepler ground-based observations, but just at the red edge derived from pulsation modeling. The pulsation models show γ Dor gravity modes driven by the convective blocking mechanism, with frequencies of 1–3 cycles per day (11 to 33 μHz). However, gravity modes were not seen in Kepler data; one signal at 1.776 cycles per day (20.56 μHz) may be attributable to a faint, possibly background, binary. [ABSTRACT FROM AUTHOR]

New insights on stellar evolution and stellar interior physics are being made possible by asteroseismology. Throughout the course of the Kepler mission, asteroseismology has also played an important role in the characterization of exoplanet-host stars and their planetary systems. The upcoming NASA Transiting Exoplanet Survey Satellite (TESS) will be performing a near all-sky survey for planets that transit bright nearby stars. In addition, its excellent photometric precision, combined with its fine time sampling and long intervals of uninterrupted observations, will enable asteroseismology of solar-type and red-giant stars. Here we develop a simple test to estimate the detectability of solar-like oscillations in TESS photometry of any given star. Based on an all-sky stellar and planetary synthetic population, we go on to predict the asteroseismic yield of the TESS mission, placing emphasis on the yield of exoplanet-host stars for which we expect to detect solar-like oscillations. This is done for both the target stars (observed at a 2-minute cadence) and the full-frame-image stars (observed at a 30-minute cadence). A similar exercise is also conducted based on a compilation of known host stars. We predict that TESS will detect solar-like oscillations in a few dozen target hosts (mainly subgiant stars but also in a smaller number of F dwarfs), in up to 200 low-luminosity red-giant hosts, and in over 100 solar-type and red-giant known hosts, thereby leading to a threefold improvement in the asteroseismic yield of exoplanet-host stars when compared to Kepler's. [ABSTRACT FROM AUTHOR]

The angle ψ between a planet’s orbital axis and the spin axis of its parent star is an important diagnostic of planet formation, migration, and tidal evolution. We seek empirical constraints on ψ by measuring the stellar inclination is via asteroseismology for an ensemble of 25 solar-type hosts observed with NASA’s Kepler satellite. Our results for is are consistent with alignment at the 2σ level for all stars in the sample, meaning that the system surrounding the red-giant star Kepler-56 remains as the only unambiguous misaligned multiple-planet system detected to date. The availability of a measurement of the projected spin–orbit angle λ for two of the systems allows us to estimate ψ. We find that the orbit of the hot Jupiter HAT-P-7b is likely to be retrograde (), whereas that of Kepler-25c seems to be well aligned with the stellar spin axis (). While the latter result is in apparent contradiction with a statement made previously in the literature that the multi-transiting system Kepler-25 is misaligned, we show that the results are consistent, given the large associated uncertainties. Finally, we perform a hierarchical Bayesian analysis based on the asteroseismic sample in order to recover the underlying distribution of ψ. The ensemble analysis suggests that the directions of the stellar spin and planetary orbital axes are correlated, as conveyed by a tendency of the host stars to display large values of inclination. [ABSTRACT FROM AUTHOR]