Caltech Optical Observatories Cahill Reference TWiki

Cahill Center for Astronomy and Astrophysics

Cahill Building Wiki: with links to general building information, email lists, maps, etc.
Conference Room Schedule

General Instrumentation Meetings and Workshops

COO Lunch Time talks

2017-06-29 ZTF Grounding and Shielding Steve Kaye
2017-07-05 Flat Field Forensics Timothee Greffe
2017-07-12 Self Encoding Electro-Permanent Magnets Justin Belicki

12:30pm Wednesdays. See links above for details.

July 19	Pavan Bilgi	Concurrent Clocking	Pavan shows off a magic trick that makes most of the parallel transfer overhead disappear and reveals his next trick which will be to make charge traps disappear.
July 26	Michael Feeney	JT Cooler Survival Guide	Michael tells how we escape from the grips of Polycold, an unreliable and expensive supplier, by developing in-house capability to diagnose and fix Cryotiger problems, find alternate sources, and refurbish used parts.
Aug 2	Delacroix	ZTF Window Supports 2 Tons	The optical design wants the window to be thinner, but if it fails it kills the instrument and we are all going to be unemployed. Come find out how we achieved adequate safety margin for this brittle component, that has to support 2 tons of atmosphere.
Aug 9	Smith and Kaye	Waveform Definition Language	We have a powerful new tool, a Waveform Compiler that interprets timing rules written in any order the user sees fit It configures the controller to make those waveforms happen, or plots them on a screen in a matter of seconds. At the same time the tool keeps the host software informed so detector engineer has a single point of control.
Aug 16	Smith	ZTF window Heater	Thermal modelling shows that ZTF window will frost up. Come hear about how our AR coating provides >30W of make up heat. We'll also look at some other radiative transport issues for ZTF, such as whether the schmidt corrector will ever fog up?
Aug 23	Steve Kaye	Optmizing the ZTF pixel timing	Squeezing the most out of the pixel time to maximize noise averaging at 1 MHz pixel rate, or to go even faster.
Aug 30	Roger Smith	Vacuum Advice	What's important? What's not? How much to pump and how seldom. Initial cleaning and baking. Use a leak detector as your pumping station, but don't do stupid stuff. Cold traps. Underlying physics. Vital roles of getters and desiccants. Gauge types and ion pumps. How your cooling system affects all this.

TBD	TBD	Focal Surface Metrology with On Sky Imaging	Deviations of ZTF CCDs from the spherical focal surface delivered by the 48" schmidt have been measured using classic through-focus scans and extra-focal image analysis. Both methods survive testing with elaborate artifical data incorporating aberrations, diffraction, beam obstructions and vignetting by primary. Results differ somewhat but both report similiar unexplained curvature. Bring your ideas.

TBD

Focal Surface Metrology with On Sky Imaging

Deviations of ZTF CCDs from the spherical focal surface delivered by the 48" schmidt have been measured using classic through-focus scans and extra-focal image analysis. Both methods survive testing with elaborate artifical data incorporating aberrations, diffraction, beam obstructions and vignetting by primary. Results differ somewhat but both report similiar unexplained curvature. Bring your ideas.

Suggestions for talks? ...contact Roger Smith, rsmith@astro.caltech.edu