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Keck Instruments. The WMKO Support Astronomer Group. Introduction. Eight facility instruments Each instrument has an assigned “Master” and a “Secondary Master.” Summit instrument group provides “hands-on” assistance. (Dwight Chan and Mike Wagner)
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Keck Instruments The WMKO Support Astronomer Group
Introduction • Eight facility instruments • Each instrument has an assigned “Master” and a “Secondary Master.” • Summit instrument group provides “hands-on” assistance. (Dwight Chan and Mike Wagner) • Summit crew does reconfigs, basic troubleshooting, etc. • Mainland observing update
Organizational Changes • Summit instrument group reorganized and refocused. • Grant Hill acting as summit liaison • Significantly improved system!
LRIS Status Marc Kassis
Recent LRIS Problems Addressed • Replaced the blue side shutter with spares (x2) • New parts machined • Spares refurbished by Caltech • Replaced damaged Blue side Dewar window • Replaced broken slitmask rollers after repeated mechanism jambs • Repaired offset guider encoder • Repaired slit viewing guider glycol leak • Replaced grating Compumotor and encoder
Recent LRIS Improvements • Software • Released slitmask imaging tool • Released automated focus routines • Implemented long slit and polarimeter focusing routines • Hardware • upgraded limit switches for slitmask grabber and trapdoor to improve reliability • Documentation • Revamped LRIS web pages • Observers very pleased with updated content • Page style may change to further improve navigation and appearance
Current LRIS Concerns • Blue and Red side shutters. • Blue shutter failure rate is 1.5 years • Red shutter does not have a good spare • Identifying possible solutions for replacement (Caltech involved) • Blue side CCD power drops (ongoing investigation) • Slitmask door mechanical problem; new latches planned • Grating port three homing problem; limit switches need adjustment • Blue side carousel flags prone to misalignment – more robust switches identified (Caltech involved)
LRIS Optical Issues • Instrument focus dependent on rotation and elevation. • LRIS rotational center is offset from the telescope’s mechanical and optical axis by 1.5 in • This affects image quality detrimentally K1+ f/15 LRIS The K1+f/15 center of rotation is marked by black theodolite cross hairs while yellow fishing line marks the center of the LRIS optical axis.Photo taken during ADC alignment by Drew Phillips.
Fe/Ar lamp 1200/3400 grism Tint=30s counts 2900 3400 3900 Angstroms Future LRIS Upgrades • Hardware • Install Fe/Ar and deuterium lamps for calibrating blue side • Improve slitmask frames • Improve slitmask guides for better reliability • Software • Develop calibration GUIS similar to DEIMOS or HIRES • Expand FITS headers to include slitmask design and target information to aid slitmask alignment & data reduction • Replace FIGDISP with DS9 reliability
LRIS Performance Monitoring • Released scripts that reconfigure the instrument and acquire throughput data • Completing LRIS mechanical checkouts prior to each observing run • Implemented software to check common detector parameters (gain, read noise, linearity).
NIRC(a.k.a. NIRC classic) Marc Kassis
Status of NIRC Classic • NIRC is rarely used • Six nights in 2006B • Four nights in 2007A • Following the earthquake • Guider was used as an emergency spare for the LRIS slit-viewing guider • Dewar was thermally cycled to address an image artifact (“flash light effect”)
HIRES Grant Hill
HIRES Recent Work • Semi-regular monitoring of detector characteristics begun, Feb. 06. • Replaced ion pump and oxygen-soaked mosaic, May 06. • Considerable progress on web pages. (Number of updated and activated pages more than doubled.) • Earthquake. • Installation of new comparison lamp begun (ongoing). • Review of spare inventory and purchases begun.
HIRES Current Issues • Further documentation and web pages improvements. • Likely to be a background effort over next year. • Goal is have manual rewritten by end of 2007. • Occasional reports of wavelength instability. • Investigations so far inconclusive. • Further experiments planned in April–June. • PM program. • PM program for all instruments proposed as an FY08 project. • Project will include predictive and preventative maintenance and performance monitoring. • Project proposal includes planning tool improvement/construction (e.g. exposure time calculator, echelle simulator, etc.)
NIRSPEC Jim Lyke
NIRSPEC • Anonymous user comments: “NIRSPEC works.” “SCAM is invaluable.” “I don’t trust the rotator.”
NIRSPEC Recent Work • NIRSPAO is back! • Six nights in Dec. 2006, including first LGS-AO night. • Two nights in June 2007. • Cold heads replaced March 16, 2005 • 65,000 operating hours (7+ years) • Server improvements have eliminated most server crashes. • EFS now allows user-defined nods
NIRSPEC Current Issues • Rotator slews move the echelle • Dispersion direction–not seen in low-res • Arc lines shift by 1 pixel • Re-emergence of an old problem; solved by replacing motor last time. • Slit primary init switch faulty • Server crashes • Rotator-caused crashes are gone • Dirty optical fibers for some • Mystery cause for others • SCAM intermittent quadrant • Ice on dewar window
NIRSPEC Window Ice • Recurring problem (every 6–12 months) • Previously, replaced window • March experiment to just warm and pump dewar was successful
NIRSPEC Ice absorption at 3.1 mm is gone Most recent: middle plot, green line Before After
NIRSPEC • Upcoming Events • NIRSPEC’s 8th Birthday April 25, 2007 • 800+ science nights allocated • Possible service for rotator and slit • MAGIQ upgrade Fall 2007
OSIRIS Jim Lyke
OSIRIS Earthquake Damage Fully functional after repair 4 nights lost (switched to NIRC2)
OSIRIS Current Issues • Small FOV • 0.32 x 1.28 arc sec • Relative astrometry vital! • Less sensitive • Calculation error • Grating efficiency • Not many papers • Data reduction difficult, but help is coming!
OSIRIS Papers The rate of papers per night for OSIRIS, a year after commissioning, is similar to the rate for NIRSPEC, a year after it commissioned. * Engineering nights not included
OSIRIS • DRP Issues • Distributed. • No mechanism to notify users of updates • New and different data products • No dedicated support • No Telluric Correction • Long integrations • Changing sky background
OSIRIS Future • What’s Next? • Papers! • Breakthrough with telluric correction • Use background region to calculate sky • Many are working on techniques and tools • Larkin, Wright, McElwain (UCLA) • Team Keck (using Director’s nights—thanks, Taft!) • Perrin, Laver, Adamkovics (UCB) • Law (CIT)
NIRC2 Al Conrad
Galaxy 4C29.28 ER2 from “Identification and Morphologies of Galaxies with Old Stellar Populations at z 2.5” Alan Stockton and Elizabeth McGrath NIRC2 Recent Work • Cold since August 2003 • Use has broadened since LGSAO commissioned • LGS/NGS ratio approx. 3-to-1 • e.g., Faint Galaxies • Calibration lamps available • Use of pupil masks increasing
NIRC2 one-second dark showing fixed pattern noise in lower left quadrant • Motor homing • Detector Noise NIRC2 Current Issues
2 data source types: Images of clusters and pin-holes NIRC2 Project: Astrometry Plate Scale Distortion Position Angle CLUSTER PINHOLE Goal: Better characterize PA, plate scale, & distortion Summary of Results: • Plate Scale: Fit residuals 0.06–0.09 pixels; 6–8 times more precise than preship values. • PA: Known to within 0.1 degrees; may improve with further analysis. • Pin-hole distortion: subpixel in the interior; 2–3 pixels at the edge.
Report: by Brian Cameron (posted on the NIRC2 web page) NIRC2 Astrometry (cont.) Narrow camera Web Page for Astrometry Calibration: • Recommended fields and observing scripts. • Voluntary repository. • dewarp tool (written in IDL). Related work: Konopacky, Britton, Lu, others.
DEIMOS Greg Wirth
DEIMOS Recent Work • DEIMOS has been working very reliably with only minor problems • Slitmask system jammed due to re-use of old and warped masks (e.g. long slits); resolved by discarding certain old masks • Spurious rotator moves during mask alignments traced to missing DCS keywords; fixed by software patch • Grating moves sometimes failed due to misalignments; fixed by revising target position
DEIMOS Current Issues • Pattern noise is present on 2 of 8 science CCDs since earthquake; troubleshooting a possible grounding problem • Slitmasks continue to generate dust that contaminates optics, but fix is costly
DEIMOS Performance Monitoring • Basic mechanical and optical checkouts performed before each run • Coatings on collimator and tent mirror being inspected and measured bimonthly for condition and reflectance • Standard star throughput data being gathered monthly; analysis pending
DEIMOS Future • Urgent • Resolve CCD noise problems • Performance Monitoring • Analyze throughput data • Clean optics and gratings • Automate monthly checkout procedures • If time permits • Commission ultrasonic slitmask cleaner • Purchase replacement clear, V filters to replace damaged ones • Install science-grade imaging mirror
ESI Greg Wirth
ESI Recent Problems • Bearing failed in middle wheel of triple-wheel assembly; UCO/Lick replaced all 6 bearings in system • Belt drive system for triple wheel has broken several times; UCO/Lick has redesigned system to improve reliability • Optical encoders on triple wheels prone to signal loss; serviced and aligned units
ESI Current Issues • Optical coupling fluid leaked onto shutter and camera optics, but has not seriously impacted observing • ESI host computer is obsolete and unreliable; UCO/Lick is helping us convert to new host computer • Collimator coating is in poor condition; needs recoating • Collimator actuator #1 fails some moves, troubleshooting in progress • Coupling to slitmask wheel is marginal, requires replacing • Flexure characteristics were rechecked and are consistent with results at commissioning
ESI Future • Urgent • Mitigate optical coupling fluid contamination • Improve triple-wheel encoder alignment • Troubleshoot failed collimator moves • Replace slitmask wheel coupling • Investigate coating options for collimator • If time allows • Upgrade host computer for maintainability • Replace FIGDISP with ds9 image display tool • Begin program of regular throughput monitoring
Mainland Observing Greg WirthBob Kibrick
Mainland Observing Background • Goal: to provide observers at mainland sites the same capabilities as in Waimea • Strategy: employ VNC software to permit sharing of desktops between observers at mainland sites and Waimea • Benefit: provides observers flexibility, e.g. to take advantage of give-back science nights, deal with personal crises, possible time-domain astronomy
Mainland Observing Status • System stable and reliable with near-zero downtime • Sites: Caltech, LBNL, UCSC, UCLA, UCSD • Instruments: all supported except IF • Usage: 142 nights since 2006A • Modes of operation: • Shared mainland and Waimea operation (84%) • Mainland-only operation (14%) • Video-only (2%)
Mainland Observing Usage by Instrument* * usage since 2006A
Mainland Observing Usage by Site* * usage since 2006A
Mainland Observing Issues • Backup lines: currently providing ISDN backup to only one site per night (limits us to only one telescope per night) • Conflicts: limited to one observing team per site • Performance: slightly slower under VNC compared to normal Waimea operation • Operation: LBNL site not yet compliant • Lacks router for ISDN backup lines • Provided computers not yet compliant