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Lawrence Bissell

Publications and source records attributed to Lawrence Bissell.

3 recordsLinked to original sources

CUBES: optical design and analysis of the VLT's high-resolution UV spectrograph past final design review

CUBES (Cassegrain U-Band Efficient Spectrograph) will be the most efficient UV spectrograph on an 8-10m class telescope, exploiting the ESO VLT's higher telescope efficiency relative to the ESO ELT in ground-based UV wavelengths. The instrument provides wavelength coverage over a range of 300-405nm, with high instrumental efficiency (>37%) and a resolving power of >20,000 (HR) and >6,000 (LR). It will be mounted on the Cassegrain focus of the VLT in Paranal. This paper presents the optical design of the system after the final design review. The optical subsystems detailed include: a pair of UV-optimized atmospheric dispersion correctors designed to function out to a zenith angle of 65{\deg}; high throughput HR and LR image slicers used to reformat the field-of-view; and a dispersion-compensating three-lens spectrographic camera design.

astro-ph.IM

METIS for ELT: optical alignment and testing of the IFU of the LM-band spectrometer

The METIS LMS (LM-band Spectrometer) is a high-resolution (R>100,000) mid-infrared integral field spectrometer for the ESO ELT. The instrument provides the capability to measure instantaneous spectra across a 0.577 x 0.897 arcsecond field-of-view with a spatial sampling of 8.2-9.1 mas using an image slicing IFU. This paper presents the optical testing and alignment performed for the IFU sub-system. This includes the detailed characterisation of the image slicing mirror array measured via: a re-imaging test in which the slicer is positioned to re-image a point source to form 28 images due to the different tilts of the 28 slicer mirrors; and precise interferometric measurements of each of the image slicer mirrors. The paper will also give an overview of the optical alignment strategy employed during the IFU AIT process in order to reach the tight alignment requirements.

astro-ph.IM

WST, the wide-field spectroscopic telescope: progress on the design of the instruments

WST, the Wide-field Spectroscopic Telescope is a proposed new facility that will provide a transformational gain in spectroscopic survey capability over existing facilities. The WST is a 12 metre class telescope equipped with instrumentation to provide simultaneous observations in both multiple-object spectroscopy and integral field spectroscopy modes. This paper will describe the status of the instruments being designed for the WST, the fibre positioner module, the low and high-resolution multiple object spectrographs, the integral field spectrograph, disperser technology, sustainable detector and cryostat technology, and the calibration system. An overview of the overall layout of the instruments within the WST facility will be provided.

astro-ph.IM