Manufacturing process for the WEAVE prime focus corrector optics for the 4.2m William Hershel Telescope

Lhomé, Émilie; Agócs, Tibor; Abrams, Don Carlos; Dee, Kevin; Middleton, Kevin; Tosh, Ian; Jaskó, Attila; Connor, Peter; Cochrane, Dave; Gers, Luke; Jonas, Graeme; Rakich, Andrew; Benn, Chris; Balcells, M.; Trager, S. C.; Dalton, Gavin; Carrasco, E.; Vallenari, A.; Bonifacio, P.; Aguerri, J. A. L.

doi:10.1117/12.2230648

Cited by 4 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The main components of the new instrument WEAVE are: a new corrector for the WHT's prime focus, delivering a 2-deg field of view. 1,2 a tumbler which can rotate between 0 and 180 deg to position one of two plates, A and B, in the focal plane a pick-and-place fibre positioner, which configures MOS fibres or integral-field units (IFUs) on one plate while observations are carried out with the other plate in the focal plane 3 a two-arm (blue and red) fibre-fed spectrograph housed on one of the WHT's Nasmyth platforms 4 a calibration unit which hosts a set of lamps for calibration images (arcs and flats)…”

Section: The Weave Instrumentmentioning

confidence: 99%

Design of the observation queue scheduler for WEAVE on the WHT

Fariña

Domínguez-Palmero

Benn

et al. 2018

Observatory Operations: Strategies, Processes, and Systems VII

Self Cite

View full text Add to dashboard Cite

The Observation Queue Scheduler (OQS) for WEAVE is described in this paper, with particular emphasis on the scheduling algorithm. WEAVE is the new 2-deg field of view multi-object (∼1000 multiplex) spectroscopy facility (R ∼ 5000 and R ∼ 20000) at the 4.2-m William Herschel Telescope. The OQS helps to maximize the scientific impact of WEAVE observations by optimising the schedule of the observing blocks, taking into account the science priority, required instrument configuration and observing constraints. On a nightly basis the OQS will assist the observer in creating a flexible queue of suitable observing blocks to be executed. It will be also possible to run a version of the OQS for extended periods of time to provide guidance on the longer-term planning of WEAVE surveys.

show abstract

Section: The Weave Instrumentmentioning

confidence: 99%

Design of the observation queue scheduler for WEAVE on the WHT

Fariña

Domínguez-Palmero

Benn

et al. 2018

Observatory Operations: Strategies, Processes, and Systems VII

Self Cite

View full text Add to dashboard Cite

show abstract

“…The initial WEAVE test setup had the lens optical axis in a vertical orientation with a fold mirror at 45 • and an ESDI-Mahr interferometer in horizontal orientation. 4 A new, higher test tower has been developed in order to accomodate the interferometer in the vertical position, avoiding the use of the fold mirror. That simplified the alignment procedure and avoided any existing vignetting issues on the fold mirror.…”

Section: Testing Processmentioning

confidence: 99%

“…The optical design and the manufacturing process for the PFC have been reported earlier. 3,4 The WEAVE PFC consists of 6 lenses (Figure 1), where 4 of them make 2 doublets with incorporated wedge for the Atmospheric Dispersion Corrector. KiwiStar's lens manufacturing process combines traditional milling, grinding and pitch polishing processes, extended to accomodate lenses up to 1.5 m in diameter with high precision metrology.…”

Section: Introductionmentioning

confidence: 99%

Testing process for the WEAVE prime focus corrector lenses for the William Herschel Telescope

Bogunovic

Jonas

Cochrane

et al. 2018

Ground-Based and Airborne Telescopes VII

View full text Add to dashboard Cite

A new prime focus corrector for the WEAVE project for the William Herschel Telescope is being produced. The corrector consists of six lens elements, the largest being 1.1 m in diameter. It also incorporates an Atmospheric Dispersion Corrector. Testing procedures for the WEAVE prime focus corrector lens elements are described here. Critical issues encountered in practice, including the influence of the lens size, wedge and weight on the testing procedure are discussed. Due to large lens dimensions, a dedicated test tower and lens support system has been developed to measure the optical surface form errors of the concave surfaces and the transmitted wavefront of each lens. For some of the lens elements, sub-aperture measurements have been performed using an off-axis Hindle sphere and the resultant OPD maps have been stitched together. The challenge of testing a wedged lens with a combination of a long radius convex surface and a short radius concave surface has been resolved by using another lens from the system as an auxiliary lens. The practice of testing convex surfaces via internal reflection/transmission through the lens element has been avoided entirely in this case and some discussion justifying the choices of metrology approach taken is given. The fabrication and acceptance testing of the lens elements has been completed within the expected time and budget, and all elements have been shown to meet requirements.

show abstract

“…It consists of four distinct subsystems: the prime focus system, 6 the spectrograph system, 7 the optical fibres, 8 and the fibre positioner 3, . 4 The prime focus system consists of a six lens wide-field corrector with atmospheric dispersion compensator 9 (ADC), an instrument rotator 10 (WRS), and a new top end structure incorporating focus/tilt adjustment to the spider vanes. The ADC components comprise two air-spaced prismatic doublets which counter-rotate to correct for dispersion along the direction of the parallactic angle.…”

Section: Introductionmentioning

confidence: 99%

Calibration at elevation of the WEAVE fibre positioner

Hughes

Dalton

Dee

et al. 2022

Ground-Based and Airborne Instrumentation for Astronomy IX

Self Cite

View full text Add to dashboard Cite

WEAVE is the new wide-field spectroscopy facility 1,2,3 for the prime focus of the William Herschel Telescope in 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 recent maintenance, flexure modifications, and calibration measurements conducted at the observatory prior to the final top-end assembly. This work ensures that we have a complete understanding of the positioner's behaviour as it changes orientation during observations. All fibre systems have been inspected and repaired, and the tumbler structure contains new clamps to stiffen both the internal beam and the retractor support disk onto which the field plates attach. We present the updated metrology procedures 4 and results that will be verified on-sky.

show abstract

Manufacturing process for the WEAVE prime focus corrector optics for the 4.2m William Hershel Telescope

Cited by 4 publications

References 1 publication

Design of the observation queue scheduler for WEAVE on the WHT

Design of the observation queue scheduler for WEAVE on the WHT

Testing process for the WEAVE prime focus corrector lenses for the William Herschel Telescope

Calibration at elevation of the WEAVE fibre positioner

Contact Info

Product

Resources

About