HARMONI - first light spectroscopy for the ELT: spectrograph camera lens mounts
(2020)
Abstract:
HARMONI is the first light visible and near-infrared (NIR) integral field spectrograph for the Extremely Large Telescope(ELT). The HARMONI spectrograph will have four near-infrared cameras and two visible, both with seven lenses of various materials and diameters ranging from 286 to 152 mm. The lens mounts design has been optimized for each lens material to compensate for thermal stresses and maintain lens alignment at the operational temperature of 130 K. We discuss their design and mounting concept, as well as assembly and verification steps. We show initial results from two prototypes and outline improvements in the mounting procedures to reach tighter lens alignments. To conclude, we present a description of our future work to measure the decentering of the lenses when cooled down and settled.
Final assembly, metrology, and testing of the WEAVE fibre positioner
Ground-based and Airborne Instrumentation for Astronomy VIII Proc. SPIE 11447 (2020) 114477R
Abstract:
WEAVE is the new wide-field spectroscopy facility for the prime focus of the William Herschel Telescope at La Palma, Spain. Its fibre positioner is essential for the accurate placement of the spectrograph's 960 fibre multiplex. We provide an overview of the final assembly and metrology of the fibre positioner, and results of lab commissioning of its robot gantries. A completely new z-gantry for each positioner robot was acquired, with measurements showing a marked improvement in positioning repeatability. We also present the first results of the configuration software testing, and discuss the metrology procedures that must be repeated after the positioner's arrival at the observatory.
HARMONI - first light spectroscopy for the ELT: final design of the integral field unit
Proceedings of SPIE--the International Society for Optical Engineering SPIE, the international society for optics and photonics 11451 (2020) 1145138-1145138-11
HARMONI - first light spectroscopy for the ELT: novel techniques for the calibration of non-common path aberrations
SPIE, the international society for optics and photonics (2020) 349
HARMONI first light spectroscopy for the ELT: geometrical calibration in the data reduction software
Proceedings of SPIE--the International Society for Optical Engineering SPIE, the international society for optics and photonics 11452 (2020) 114522t-114522t-16