Edward Gillen

CoRoT 223992193: A new, low-mass, pre-main sequence eclipsing binary with evidence of a circumbinary disk

We present the discovery of CoRoT 223992193, a double-lined, detached eclipsing binary, comprising two pre-main sequence M dwarfs, discovered by the CoRoT space mission during a 23-day observation of the 3 Myr old NGC 2264 star-forming region. Using multi-epoch optical and near-IR follow-up spectroscopy with FLAMES on the Very Large Telescope and ISIS on the William Herschel Telescope we obtain a full orbital solution and derive the fundamental parameters of both stars by modelling the light curve and radial velocity data. The orbit is circular and has a period of 3:8745745 0:0000014 days. The masses and radii of the two stars are 0:67 0:01 and 0:495 0:007 M and 1:30 0:04 and 1:11 +0:04 0:05 R , respectively. This system is a useful test of evolutionary models of young low-mass stars, as it lies in a region of parameter space where observational constraints are scarce; comparison with these models indicates an apparent age of 3.5‐6 Myr. The systemic velocity is within 1 of the cluster value which, along with the presence of lithium absorption, strongly indicates cluster membership. The CoRoT light curve also contains large-amplitude, rapidly evolving out-of-eclipse variations, which are di cult to explain using starspots alone. The system’s spectral energy distribution reveals a mid-infrared excess, which we model as thermal emission from a small amount of dust located in the inner cavity of a circumbinary disk. In turn, this opens up the possibility that some of the out-of-eclipse variability could be due to occultations of the central stars by material located at the inner edge or in the central cavity of the circumbinary disk.

Rotation in the Pleiades with K2. I. Data and first results

Young (125 Myr), populous (

Rotation in the Pleiades with K2. II. Multiperiod stars

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New Low-mass Eclipsing Binary Systems in Praesepe Discovered by K2

1000 members), and relatively nearby, the Pleiades has provided an anchor for stellar angular momentum models for both younger and older stars. We used K2 to explore the distribution of rotation periods in the Pleiades. With more than 500 new periods for Pleiades members, we are vastly expanding the number of Pleiads with periods, particularly at the low mass end. About 92\% of the members in our sample have at least one measured spot-modulated rotation period. For the

Centroid vetting of transiting planet candidates from the Next Generation Transit Survey

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NGTS-1b: A hot Jupiter transiting an M-dwarf

8\% of the members without periods, non-astrophysical effects often dominate (saturation, etc.), such that periodic signals might have been detectable, all other things being equal. We now have an unusually complete view of the rotation distribution in the Pleiades. The relationship between

The doubly eclipsing quintuple low-mass star system 1SWASP J093010.78+533859.5

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NGTS-2b: an inflated hot-Jupiter transiting a bright F-dwarf

and

A low-mass eclipsing binary within the fully convective zone from the Next Generation Transit Survey

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Automatic vetting of planet candidates from ground based surveys: Machine learning with NGTS

follows the overall trends found in other Pleiades studies. There is a slowly rotating sequence for