DEIMOS Quarterly Report

Number 14

October 1, 1997 - December 31, 1997

 

 

 

1. General Items:

 

Completion of the optics and camera is now on the critical path. The CaF2 blank for camera Element 3 has been successfully generated by Optovac and United Lens and is currently in the Optical Lab. Fine grinding and polishing are scheduled to start in early March, following the completion of Element 1 around the end of February [now expected March 20]. The completion of Element 4 was delayed pending delivery of the blank for Element 3, and we will likely resume work on it in mid-February. The pickup surface of Element 6 will be the last surface to be optically figured. The current schedule calls for work to start on this surface towards the end of March.

 

Sandy Faber is corresponding with Coherent, Inc., regarding the optical coatings for the camera elements and the spectrograph window.

 

We have expanded our list of possible optical couplants to five Cargille fluids, including Laser Liquid 5610, which is planned to be used in ESI. We have contracted with Silicon Valley Chemlabs to investigate the reactivity with RTV. We are also conducting tests on the reactivity of these liquids with the "O" rings and the material that will be used as the bladder material in the camera barrel.

 

A Critical Design Review of the camera barrel was held on November 14, 1997, which covered many important points and caused us to simplify the design. The design was simplified as a result of the review. The detailed design is currently in progress with the expectation of a pre-fabrication review of the drawing in late January [this has occurred]. The schedule shows our completing the fabrication of the barrel by mid-April 1998.

 

Fabrication and testing of components for the grating system continues. Our current expectation is to complete the design of all major components by mid-May and fabrication by mid-summer.

 

We have now powered the slit mask cassette and are starting tests of the system. Earlier tests showed that the cassette has considerable flexure with changing gravity direction, and modifications are currently being designed. The goal is to have a working system by the end of the March.

A new encoder system for the position angle drive is currently being tested. Completion of this task has been delayed, but we are planning to have the encoder installed soon.

 

Testing of the MIT/LL CCDs was completed for the first round of distribution to the consortium. This is scheduled for early next quarter [it occurred].

 

A completed Leach-2 controller for the FC system was delivered to the CCD Lab in November 1997. This system is being tested with the ESI dewar using a 2Kx4K orbit chip. Once tests confirm the design of the controller, we will start fabrication of the science system. The schedule calls for the science controller to be complete by the end of April 1998.

 

The electronics on the rotating part of DEIMOS are currently being mounted on panels that will be integrated into the electronic enclosure that surrounds the rotating part of the instrument. The motor controller portions are expected to be installed on DEIMOS by mid-February.

 

Software for simulating the operation of KTL-based instruments was developed and successfully used to test and demonstrate the DEIMOS GUI. The DEIMOS GUI Review was held on December 16th and the overall reaction was positive. A report summarizing the results of that review is attached.

 

Progress continues in several other software areas. The existing figdisp image display protocol has been successfully updated to operate across any combination of 32-bit or 64-bit platforms regardless of byte ordering, and implementation of the shared-memory-signaling protocol extension has commenced. Work has also begun on implementation of the database quality assurance suite, with some components now operational.

 

The three Ultraserver 450 computers donated to the DEEP/DEIMOS project by Sun Microsystems were shipped in mid-December, and one each received at UCB and UCSC, [the third machine arrived at UCSC in early January]. The prototype version of the second-generation SDSU VME interface board was also received in mid-December.

 

 

2. Reports on Specific Areas:

 

2.1 Optics

Aspheric grinding and polishing was performed on Element 1, and at the end of this reporting period the figuring was approximately 75% complete. The OFFCTR value as reported by Curvmon remains at about .0016", which is within the tolerance goals. We expect the remaining 25% of the figuring process to be slower because of the need for more tests and shorter polishing runs. We expect to complete this aspheric surface by early March.

 

The DEIMOS entrance window will be made at Eastman Kodak for an approximate cost of $16K and delivered by June 1, 1998.

 

The lens blank for Element 4 was generated on the concave side and then put on hold awaiting the arrival of the CaF2 blank for Element 3 from Optovac. [This blank arrived in February, so Element 4 can now go forward.]

 

An extensive study was made of Cargille optical coupling fluids for the camera, and five candidate fluids were selected. Reactivity tests of the candidate couplant fluids on the exposed glass materials, RTV, and "O" ring materials were begun by immersing the materials in the fluids and placing the samples in an oven set at 35° C. The vinyl bladder candidates will be tested in a similar manner. Samples of candidate vinyls have been ordered from Vinyltech.

 

A letter was prepared and sent to Coherent, Inc., describing the coating requirements for the DEIMOS camera. Coherent successfully coated the ESI optics, which are similar. They responded favorably to our project and promised to provide a quote in early 1998. [This quote arrived February 20, 1998.]

 

2.2 Mechanical Design

Structure:

The design for the installation of the Renishaw encoder has been completed and the parts fabricated. Tests have been conducted to attempt to read over the gap at the ends of the tape. These have not been successful to date but are not vital since two encoders are being used. Further tests of the PA drive are on hold until the grating system is installed and properly counterweighted.

 

The cable wrap for the DEIMOS cylinder has been designed and partially built. For better packaging, we are using a cable chain that falls into a tray on the back of DEIMOS. The cable chain has been ordered and the spiral hub for winding up the chain has been made. A meeting with Barry Alcott, Bob Kibrick, and Chris Wright reduced the cable count requirement through the rear bearing significantly.

 

The electronics ring has been permanently installed, and mounting platforms for some of the components have been made and test fitted prior to populating them. The inner insulation of the electronics ring between the ring and skin has been installed.

 

Gratings: