Exoplanets and Stellar Physics

Abstract:

We review the observations of extrasolar planets, ongoing developments in theories of planet formation, orbital migration and the evolution of multiplanet systems. © 2006 IOP Publishing Ltd.

Abstract:

We report on the results of a V- and i-band time-series photometric survey of M34 (NGC 1039) using the Wide Field Camera (WFC) on the Isaac Newton Telescope (INT), achieving better than 1 per cent precision per data point for 13 lsim; i ≲ 17. Candidate cluster members were selected from a V versus V - I colour-magnitude diagram over 14 < V < 24 (0.12 ≲ M/M⊙ 1.0), finding 714 candidates, of which we expect ∼400 to be real cluster members (taking into account contamination from the field). The mass function was computed, and found to be consistent with a lognormal distribution in dN/d log M. Searching for periodic variable objects in the candidate members gave 105 detections over the mass range 0.25 < M/M⊙ < 1.0. The distribution of rotation periods for 0.4 < M/M⊙ < 1.0 was found to peak at ∼7 d, with a tail of fast rotators down to periods of ∼0.8 d. For 0.25 < M/M⊙ < 0.4 we found a peak at short periods, with a lack of slow rotators (e.g. P ≳ 5 d), consistent with the work of other authors at very low masses. Our results are interpreted in the context of previous work, finding that we reproduce the same general features in the rotational period distributions. A number of rapid rotators were found with velocities ∼ a factor of 2 lower than in the Pleiades, consistent with models of angular momentum evolution assuming solid body rotation without needing to invoke core-envelope decoupling. © 2006 RAS.

Abstract:

SWIFT is an adaptive optics assisted integral field spectrograph covering the I and z astronomical bands (0.7-1.0 mu m) at a spectral resolving power R <= 5000. At its heart is an all-glass image slicer with high throughput based on a novel de-magnifying design allowing a compact instrument. SWIFT profits from two recent developments: (i) the improved ability of second generation adaptive optics systems to correct for atmospheric turbulence in SWIFTS's bandpass, and (ii) the availability of CCD array detectors with high quantum efficiency at very red wavelengths. It is a dedicated integral field spectrograph, specifically built to address a range of interesting astrophysical questions. (c) 2005 Elsevier B.V. All rights reserved.

Abstract:

KMOS is a near-infrared multi-object integral field spectrometer which has been selected as one of a suite of second-generation instruments to be constructed for the ESO VLT in Chile. The instrument will be built by a consortium of UK and German institutes working in partnership with ESO and is currently at the end of its preliminary design phase. We present the design status of KMOS and discuss the most novel technical aspects and the compliance with the technical specification.

Abstract:

We present the optical and mechanical design of the KMOS spectrograph module together with a detailed analysis of its performance. KMOS is a cryogenic near-infrared multi-object spectrograph being developed as a second-generation instrument for the VLT by a consortium of UK and German institutes. Three identical spectrograph modules provide Nyquist sampled spectra in the wavelength range covering the atmospheric bands z, J, H, and K with a resolving power exceeding 3200. The spectrographs are fully achromatic over the bands and the single mirror collimator and six-element camera, together with six high efficiency gratings provide high throughput. The optical performance analysis includes amongst others the spectral resolving power and variation of the PSF as a function of the pupil illumination.