Current status of the Hobby-Eberly Telescope wide field upgrade

Hill, Gary J.; Booth, John A.; Cornell, Mark E.; Good, John M.; Gebhardt, Karl; Kriel, Herman; Lee, Hanshin; Leck, Ron; Moreira, Wálter; MacQueen, Phillip J.; Perry, Dewayne E.; Rafal, Marc D.; Rafferty, Tom; Ramiller, C. L.; Savage, Richard; Taylor, Charles A.; Vattiat, Brian L.; Ramsey, Lawrence W.; Beno, J.H.; Beets, Timothy A.; Esguerra, Jorge D.; Häuser, Marco; Hayes, Richard; Heisler, J T; Soukup, Ian; Zierer, Joseph; Worthington, Michael S.; Mollison, Nicholas T.; Wardell, D.; Wedeking, G.A.

doi:10.1117/12.925435

Cited by 33 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…VIRUS is the massively replicated spectrograph being built and installed at the newly upgraded Hobby Eberly Telescope (HET) for HETDEX -The Hobby Eberly Telescope Dark Energy eXperiment (1)(2)(3). VIRUS consists of 156 identical spectrograph channels contained in 78 identical units (4,5).…”

Section: Introductionmentioning

confidence: 99%

VIRUS early installation and commissioning

et al. 2016

Self Cite

View full text Add to dashboard Cite

VIRUS is a massively replicated spectrograph built for HETDEX, the Hobby Eberly Telescope Dark Energy Experiment. It consists of 156 channels within 78 units fed by 34944 fibers over the 22 arcminute field of the upgraded HET. VIRUS covers a relatively narrow bandpass (350-550nm) at low resolution (R ⇠ 700) to target the emission of Lyman-alpha emitters (LAEs) for HETDEX. VIRUS is a first demonstration of industrial style assembly line replication in optical astronomy.Installation and testing of VIRUS units began in November of 2015. This winter we celebrated the first on sky instrument activity of the upgraded HET, using a VIRUS unit and LRS2-R (the upgraded facility Low Resolution Spectrograph for the HET). Here we describe progress in VIRUS installation and commissioning through June 2016. We include early sky data obtained to characterize spectrograph performance and on sky performance of the newly upgraded HET. As part of the instrumentation for first science light at the HET, the IFU fed spectrographs were used to test a full range of telescope system functionality including the field calibration unit (FCU). We also use placement of strategic IFUs to map the new HET field to the fiber placement, and demonstrate actuation of the dithering mechanism key to HETDEX observations.

show abstract

Section: Introductionmentioning

confidence: 99%

VIRUS early installation and commissioning

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…2) is being constructed 3 for the upgraded 9.2 m Hobby-Eberly Telescope (HET * ; Ref. 4). The VIRUS spectrograph array consists of at least 150 copies (with a goal of 192) of a simple fiber-fed integral field spectrograph and for the first time has introduced industrial-scale replication to optical astronomical instrumentation.…”

Section: Introductionmentioning

confidence: 99%

Methods for evaluating the performance of volume phase holographic gratings for the VIRUS spectrograph array

Chonis

Hill

Clemens³

et al. 2012

SPIE Proceedings

Self Cite

View full text Add to dashboard Cite

The Visible Integral field Replicable Unit Spectrograph (VIRUS) is an array of at least 150 copies of a simple, fiber-fed integral field spectrograph that will be deployed on the Hobby-Eberly Telescope (HET) to carry out the HET Dark Energy Experiment (HETDEX). Each spectrograph contains a volume phase holographic grating as its dispersing element that is used in first order for 350 < λ(nm) < 550. We discuss the test methods used to evaluate the performance of the prototype gratings, which have aided in modifying the fabrication prescription for achieving the specified batch diffraction efficiency required for HETDEX. In particular, we discuss tests in which we measure the diffraction efficiency at the nominal grating angle of incidence in VIRUS for all orders accessible to our test bench that are allowed by the grating equation. For select gratings, these tests have allowed us to account for > 90% of the incident light for wavelengths within the spectral coverage of VIRUS. The remaining light that is unaccounted for is likely being diffracted into reflective orders or being absorbed or scattered within the grating layer (for bluer wavelengths especially, the latter term may dominate the others). Finally, we discuss an apparatus that will be used to quickly verify the first order diffraction efficiency specification for the batch of at least 150 VIRUS production gratings.

show abstract

“…The new Wide-Field Corrector (WFC) replaces the old SAC, thereby widening the telescope instantaneous field of view (FOV) from 4 arcmin to 22 arcmin in diameter, increasing the telescope aperture from 9.2m to 10m, and finely tuning the focal ratio to f/3.65 ideal for coupling optical fibers at its focal surface [1]. Much improved all-kinematic and passively athermalized opto-mechanical structures [2] ensures the structural stability of the system over the range of motions and temperatures to which the WFC is subject and the state-of-the-art protected silver reflective coatings ensures the highest telescope photon efficiency possible across the wavelength range from 360nm to 1800nm.…”

Section: Introductionmentioning

confidence: 99%

Delivery, installation, on-sky verification of the Hobby Eberly Telescope wide field corrector

et al. 2016

Self Cite

View full text Add to dashboard Cite

The Hobby-Eberly Telescope (HET) † , located in West Texas at the McDonald Observatory, operates with a fixed segmented primary (M1) and has a tracker, which moves the prime-focus corrector and instrument package to track the sidereal and non-sidereal motions of objects. We have completed a major multi-year upgrade of the HET that has substantially increased the pupil size to 10 meters and the field of view to 22 arcminutes by deploying the new Wide Field Corrector (WFC), new tracker system, and new Prime Focus Instrument Package (PFIP). The focus of this paper is on the delivery, installation, and on-sky verification of the WFC. We summarize the technical challenges encountered and resolutions to overcome such challenges during the construction of the system. We then detail the transportation from Tucson to the HET, on-site ground verification test results, post-installation static alignment among the WFC, PFIP, and M1, and on-sky verification of alignment and image quality via deploying multiple wavefront sensors across 22 arcminutes field of view. The new wide field HET will feed the revolutionary new integral field spectrograph called VIRUS, in support of the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), a new low resolution spectrograph (LRS2), an upgraded high resolution spectrograph (HRS2), and later the Habitable Zone Planet Finder (HPF).

show abstract

Current status of the Hobby-Eberly Telescope wide field upgrade

Cited by 33 publications

References 0 publications

VIRUS early installation and commissioning

VIRUS early installation and commissioning

Methods for evaluating the performance of volume phase holographic gratings for the VIRUS spectrograph array

Delivery, installation, on-sky verification of the Hobby Eberly Telescope wide field corrector

Contact Info

Product

Resources

About