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High-resolution spectrometers are nowadays achievable in compact devices using integrated optics. The approach developed here consists in obtaining a static interferogram by means of a Fresnel reflection at the waveguide output (Lippmann interference between forward and backward beams) and then sample the fringes by periodically etching the waveguide with transverse nanogrooves, that will collect a negligible part of the flux. We present the first SWIFTS-Lippmann interferometer in the near and mid-infrared, thanks to high form factor grooves obtained by focused ion beam in lithium niobate, which opens the way to electrooptic modulation of the interferogram and thus, sampling on-chip, without any moving part. Possible applications are high-resolution spectroscopy and accurate measurement of effective refractive index of a waveguide. A measurement of the effective group refractive index of the guided mode is presented. [ABSTRACT FROM PUBLISHER]

This work describes an extensive and eminently observational study, carried out with an Hα filter, of the kinematics of the ionized gas in the large emission region (220 pc) DEM L208 which is located in the south-east part of the Large Magellanic Cloud (LMC). The intention was to establish the region's general kinematic and morphological characteristics, and to analyse its possible association with a larger structure, aiming above all to contribute to the elaboration of a detailed global kinematics image of the LMC. The nebula's edges are well defined, with fairly regular Gaussian profiles, and can be represented by a systemic radial velocity of approximately 250 km s−1 for the brightest area of DEM L208. The radial velocity fields obtained present a main component with a well-defined profile, as well as other weaker components of larger speed, which may be indicative of expansion motion or of another layer of gas. In some regions we find evidence that the disturbance of the medium is due to stellar winds from the interior of the nebula; in others the profiles observed are found to be consistent with very intense stellar winds from Wolf–Rayet stars. [ABSTRACT FROM PUBLISHER]

Thanks to development of some new detectors small compare to wavelength of detected wave, as we foreseen in SWIFTS that these detectors can be placed in the vanishing field along propagation of light in order to detect the Lippmann interferogram, we propose here to present basic of SWIFTS and review some concepts where detectors has already set inside optical components and thinking about extensions of the concept of SWIFTS in new optical instrumentation by including directly detectors inside optical component. [ABSTRACT FROM AUTHOR]

This paper presents the status of the EPICS project, an Earth-like Planets Imaging Camera Spectrograph for OWL. We present the Top-Level-Requirements of the instrument and we describe the baseline of the Adaptive Optics system with optimized wave-front sensor. The expected performance in rejection of starlight in the near infrared and in the visible is given. The instruments concepts for detection and characterization of exo-planets will be briefly described. The Signal-to-Noise ratio estimation shows that Earth-like planets can be detected up to 20 pc in a reasonable amount of time. The extremely challenging requirements in terms of static residual errors and differential aberrations are discussed. [ABSTRACT FROM PUBLISHER]

We report the results of a kinematic Hα survey of the Large Magellanic Cloud (LMC) in the form of a kinematic and photometric catalogue of 210 HII regions, the radial velocity field of the ionized hydrogen in this galaxy, and the LMC Rotation Curve obtained from the velocity field. These data aim at understanding the LMC HII regions, bubbles and superbubbles in a global (galactic) scale so that we could have a 3D view and separate the rotation due to gravitational potential from other motions such as expansions. [ABSTRACT FROM PUBLISHER]