Because of the development of large-format, wide-field cameras, microlensing surveys are now able to monitor millions of stars with sufficient cadence to detect planets. These new discoveries will span the full range of significance levels including planetary signals too small to be distinguished from the noise. At present, we do not understand where the threshold is for detecting planets. MOA-2011-BLG-293Lb is the first planet to be published from the new surveys, and it also has substantial followup observations. This planet is robustly detected in survey+followup data (∆χ 2 ∼ 5400). The planet/host mass ratio is q = 5.3 ± 0.2 × 10 −3 . The best fit projected separation is s = 0.548 ± 0.005 Einstein radii. However, due to the s ↔ s −1 degeneracy, projected separations of s −1 are only marginally disfavored at ∆χ 2 = 3. A Bayesian estimate of the host mass gives M L = 0.43 +0.27 −0.17 M ⊙ , with a sharp upper limit of M L < 1.2 M ⊙ from upper limits on the lens flux. Hence, the planet mass is m p = 2.4 +1.5 −0.9 M Jup , and the physical projected separation is either r ⊥ ≃ 1.0 AU or r ⊥ ≃ 3.4 AU. We show that survey data alone predict this solution and are able to characterize the planet, but the ∆χ 2 is much smaller (∆χ 2 ∼ 500) than with the followup data. The ∆χ 2 for the survey data alone is smaller than for any other securely detected planet. This event suggests a means to probe the detection threshold, by analyzing a large sample of events like MOA-2011-BLG-293, which have both followup data and high cadence survey data, to provide a guide for the interpretation of pure survey microlensing data.

Bennett et al.

No abstract

We present the physical properties of V404 Lyr exhibiting eclipse timing variations and multiperiodic pulsations from all historical data including the Kepler and Super-WASP observations. Detailed analyses of 2,922 minimum epochs showed that the orbital period has varied through a combination with an upward-opening parabola and two sinusoidal variations, with periods of P 3 =649 d and P 4 =2,154 d and semi-amplitudes of K 3 =193 s and K 4 =49 s, respectively. The secular period increase with a rate of +1.41 ×10 −7 d yr −1 could be interpreted as a combination of the secondary to primary mass transfer and angular momentum loss. The most reasonable explanation for both sinusoids is a pair of light-travel-time effects due to two circumbinary objects with projected masses of M 3 =0.47 M ⊙ and M 4 =0.047 M ⊙ . The third-body parameters are consistent with those calculated using the Wilson-Devinney binary code. For the orbital inclinations i 4 43 • , the fourth component has a mass within the hydrogen-burning limit of ∼0.07 M ⊙ , which implies that it is a brown dwarf. A satisfactory model for the Kepler light curves was obtained through applying a cool spot to the secondary component. The results demonstrate that the close eclipsing pair is in a semi-detached, but near-contact, configuration; the primary fills approximately 93% of its limiting lobe and is larger than the lobe-filling secondary. Multiple frequency analyses were applied to the light residuals after subtracting the synthetic eclipsing curve from the Kepler data. This revealed that the primary component of V404 Lyr is a γ Dor type pulsating star, exhibiting seven pulsation frequencies in the range of 1.85−2.11 d −1 with amplitudes of 1.38−5.72 mmag and pulsation constants of 0.24−0.27 d. The seven frequencies were clearly identified as high-order low-degree gravity-mode oscillations which might be excited through tidal interaction. Only eight eclipsing binaries have been known to contain γ Dor pulsating components and, therefore, V404 Lyr will be an important test-bed for investigating these rare and interesting objects.

Measuring solar‐like oscillations in an ensemble of stars in a cluster, holds promise for testing stellar structure and evolution more stringently than just fitting parameters to single field stars. The most‐ambitious attempt to pursue these prospects was by Gilliland et al. who targeted 11 turn‐off stars in the open cluster M67 (NGC 2682), but the oscillation amplitudes were too small (<20 μmag) to obtain unambiguous detections. Like Gilliland et al. we also aim at detecting solar‐like oscillations in M67, but we target red giant stars with expected amplitudes in the range 50–500 μmag and periods of 1 to 8 h. We analyse our recently published photometry measurements, obtained during a six‐week multisite campaign using nine telescopes around the world. The observations are compared with simulations and with estimated properties of the stellar oscillations. Noise levels in the Fourier spectra as low as 27 μmag are obtained for single sites, while the combined data reach 19 μmag, making this the best photometric time series of an ensemble of red giant stars. These data enable us to make the first test of the scaling relations (used to estimate frequency and amplitude) with an homogeneous ensemble of stars. The detected excess power is consistent with the expected signal from stellar oscillations, both in terms of its frequency range and amplitude. However, our results are limited by apparent high levels of non‐white noise, which cannot be clearly separated from the stellar signal.