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This agreement is between the Carnegie Observatories (OCIW), representing the MagE instrument team, and the Magellan technical staff, representing the Magellan Consortium.
A summary of the instrument specifications can be found at http://www.lco.cl/lco/magellan/instruments/specs/mage_specs.html
A more detailed description of the characteristics and operation of the instrument can be found in the user's manual located at: http://www.lco.cl/lco/magellan/instruments/mage/mage_manual.html
MagE will be mounted at the Magellan II (Clay) central folded port (FP2).
Regular secondary (original f/11 Gregorian).
MagE uses a regular folded-port guider. In addition, there is a Magellan guide CCD camera mounted on the MagE slit-viewing port.
The instrument (900 lbs) and cable wrap (100 lbs) weigh a total of 1000 pounds.
There is one instrument electronics box mounted on the side of the instrument. There is also a 48-volt power supply mounted on the side of the telescope to power the science CCD and slit viewing CCD camera electronics.
The science CCD is controlled with a computer mounted in a rack in the telescope equipment room. MagE will use one of the five identical computers in the rack; two are used by MIKE, another is used by LDSS3, and the fifth is a spare.
The cryotiger compessor is mounted on an exiting rack mounted under the telescope azimuth disk.
The MagE data acquisition GUI will run on the astronomer computer in the observing room. This computer will communicate directly with the CCD control computer via ethernet. The acquisition GUI will also run via an instrument computer should one be installed.
The MagE gui will also communicate with the instrument control via ethernet, allowing remote control of slit position, collimator focus, and operation of the comparison lamps and flipper mirror. Control for these functions is also available at the instrument electronics box.
MagE is balanced on the rotator with weights selected to set the center of gravity of the instrument at the center of rotation. The telescope balance will need to be adjusted to compensate for the additional weight of MagE.
MagE will run with the standard folded port baffle now being designed.
Cables to the instrument are: UPS fed 110-V to the electronics box, ethernet line to the electronics box, optical fiber from the equipment room to the science CCD saddlebag, communications and cooling lines to the slit viewing CCD camera, and cryotiger lines to the science CCD camera, 48-volt lines to the CCD saddlebag and the slit viewing CCD camera..
There is a junction plate on the instrument which provides disconnect points for the cryotiger lines, the glycol coolant, and the 48-volt lines to the CCD cameras. The ethernet line, the 110-V line, the communications line to the slit viewing camera, and the science CCD camera fiber line are run directly to the appropriate points on the instrument.
The cable wrap will accomodate all of these lines, and is a new design that is be identical to the cable wrap used with MagIC on the Magellan I (Baade) telescope.
Instrument glycol coolant is required for the slit viewing CCD guide camera.
A total of 40 watts of power is required to run the instrument electronics when no lamps or motors are being run. The flash (flat field) lamp consumes 15 watts when running, the comparison lamp consumes 5 watts, the focus motor consumes 20 watts, the slit motion consumes 5 watts. Only one of these components will be running at any given time.
The CCD camera consumes 20 watts when the temperature control resistors are turned on full. The camera consumes about 15 watts at its normal operating temperature.
The slit viewing camera consumes 10 watts.
There is presently no ducting of heat generated by the instrument.
No cryogens will be required.
The science camera is cooled by a cryotiger, and so requires no active maintenance by Observatory staff.
The instrument will be provided with a permanently attached ion pump, which should be operating at all times to maintain the vacuum in the dewar.
Once installed, the instrument should not need to be removed from the folded port under normal circumstances.
Observatory staff will make the following tests on a routine basis:
1) Noise and linearity tests for the dewar. There is an IRAF script called XXX mage_gain.cl to do a full test based on a pair of flat and bias frames. These tests are made by the Instrument Specialists and should be scheduled about every two weeks of routine use or unbroken on the telescope. The time required to take two flat and two bias frames, to run the script, and to document the results is less than one hour.
2) The instrument is focussed with an IRAF script (XXX mage_focus.cl), a full focus sequence takes about one hour. The focus is not very sensitive to temperature, so refocussing should only be required after significant changes of the instrument. The change in focus from 0 C to 20 C is 0.5 mm, which corresponds to a spot size of 0.14 arcsec at the telescope focal plane. Instrument specialists are requested to document final focus values together with the instrument temperature for each focus sequence.
3) The dewar vacuum should be maintained by the ion pump. The dewar vacuum should be monitored occasionally. The expected lifetime of the ion pump is in excess of five years at the pressure achieved during the commissing run.
Instrument Specialist: Routine work approximately two to three hours per two week period when the instrument is scheduled (two focus sequences, one noise measurement). The instrument has a fixed optical with the exception of a movable slit plate, and so in principle should be easy to use. However, when a new observer is scheduled to use the instrument the Instrument Specialist might spend up to two hours in observer support introducing the observer to the instrument. Occasional additional work on the instrument electronics is required to help troubleshoot problems. When the instrument is not in use, the Instrument Scientist should occasionally monitor the dewar pressure and the CCD temperature. This requires starting the instrument GUI.
Electronics Engineer: In charge of maintaining the cables and fiber lines to the CCD cameras and the cables and coolant lines to the slit viewing camera, all of which should need service only very rarely. Occasional work on the instrument electronics.
Instrument Scientist: Occasional consulting work to debug problems and to discuss the general health of the instrument with the instrument team.
Pasadena Staff (mainly Birk, Burley, Estrada, Marshall and Thompson): As needed for upgrades and maintenance of software, computers, and control and communications electronics. Instrument status reported in the daily telescope reports is monitored by Birk, Burley, Shectman, and Thompson. The manual is maintained by Marshall with assistance from Thompson.
No consumables will be required for operations.
See above.
The instrument should only rarely be removed from the telescope. In the event of an instrument change, the following procedures should be followed:
1) Control GUI: The command GUI is launched in any xterm window on the astronomer's computer with the command "mage". An option exists to control the font size (as in "mage -h 14"). Complete details are found in the MagE manual (link exists from the Magellan Instruments web page). To shut down the program, the GUI should be exited using the appropriate command.
2) Cabling to the instrument:
a) optical fiber connecting the saddlebag to the ccd control computer in the dome equipment room.
b) power cable to the electronics box.
c) 48-volt power cables for the slit viewing and science CCD cameras.
d) coolant lines to the slit viewing guider camera.
e) ethernet line to the electronics box.
f) signal cable to the slit viewing CCD camera.
3) Pump down procedure: Normal dewar vacuum practices, final target pressure is less than 1e-6 on the vacuum pump electronic gauge. The vacuum is monitored with a vacuum guage. The ion pump will not work if the vacuum is greater than 1e-5 mbar, operation of the ion pump is gated by the gauge pressure reading.
4) Warm up procedure. The dewar should be warmed by turning off the cryotiger cooler. The getter is charcoal and is mounted directly to the cold head of the cryotiger, and will outgas as the cryotiger warms up. Tests in the lab indicate that the cryotiger remains the coldest spot in the dewar during a warmup, however to be safe the dewar should be pumped as it warms up. This will either require a short period of time when the cryotiger is off and coming to pressure equilibrium before the instrument is lowered to the observing floor and connected to the pump, or ensuring that the cryotiger lines are long enough to allow the instrument to be lowered to the dome floor with the cryotiger compressors running.
The warmup MAY NOT be accelerated by leaking a small amount of air into the science camera.
The results of all routine tests should be posted on the daily telescope reports, and are archived through these reports.
CCD Cameras:
Spare electronics boards for the camera are shared with the MIKE, LDSS3, and IMACS cameras and are found in the CCD lab room in the Instrument Support Building. The mountain staff should inform Burley or Thompson whenever any of these spares is used and arrange to have any defective boards returned to Pasadena for repair. Defective boards are occasionally repaired on site by the Electronics Engineers, depending on the problem.
A spare CCD control computer, including communications board, is located in the CCD computer rack in the telescope equipment room. This spare computer has the necessary code to run the MagE camera.
Instrument spares: The following spares are to be found in the MagE cabinet in the Auxiliary Building: Shutter, ThAr and Xenon flash lamps, focus and slit plate motors, flipper mirror mechanism for comparison lamps, flipper mirror controller, encoder potentiometers for both focus and slit position, two ion pumps and one ion pump controller, PLC chassis power supplies, assorted PLC components, CCD camera o-rings.
The MagE general distribution email alias is mage lco.cl (XXX Need to make this?). The main contact individuals are
Christoph Birk (birk ociw.edu)
Scott Burles (sburles gmail.com)
Greg Burley (burley ociw.edu)
Jorge Estrada (estrada ociw.edu)
Jennifer Marshall (marshall ociw.edu)
Steve Shectman (shec ociw.edu)
Ian Thompson (ian ociw.edu)
CCD camera issues: Burley, Estrada, Thompson
Instrument performance: Burles, Marshall, Shectman
Acquisition program performance: Birk, Burley, Thompson
All of the above receive copies of the daily reports when MagE is used for observing. Birk, Shectman, and Thompson receive copies of all daily reports and can monitor work on MagE during engineering or when it is not used for observing.
The mountain staff can service the instrument electronics box. The PLC electronics and control software were developed by Patricio Jones and Jorge Estrada, they are the principle contacts for this part of the instrument. These electronics control the slit plate motion, calibration pickoff mirror motion, ThAr and quartz lamps, and the shutter.
Given that the instrument is mounted at a folded port, pumping the dewar is not a routine operation, and should be scheduled only in consultation with the instrument team. The safest procedure will be to remove the instrument from the telescope. Experience with ion pumps at SAO indicates that they are able to hold the vacuum for long periods of time. It is anticipated that the dewar might need to be pumped once per year.
The external power supplies for the CCD cameras and the guiders are idential in design to those used with other guider and science CCD cameras, and can be maintained by the local staff. The mountain staff may swap boards in the CCD saddlebag in the process of troubleshooting problems with the performance of the CCD; a detailed record of any such swaps and final board distribution will be summarized in the daily telescope reports and recorded in a log book kept in the Astronomer Support Building CCD lab.
The CCD is controlled by a computer mounted in a rack in the dome equipment room. The rack will have five identical computers, four of which are used at any one time to control the MagE, MIKE, and LDSS3 dewars. Input to these computers may be swapped by the mountain staff (the acquisition program has to be restarted if a swap is made).
In general the local staff should not adjust the internal optics of the instrument or calibration system, or anything inside the CCD dewars without consulting Burles, Burley, Marshall, Shectman, and/or Thompson.
For problems with CCD performance contact Burley or Thompson. For problems with data acquisition contact Birk. For problems with the spectrograph contact Burles, Marshall, or Shectman. Contact can be made by email or telephone.
Carnegie Observatories assumes the responsibility for supplying replacement parts and contracted services, including outside consultants. Authorization will be from Shectman or Thompson. Parts and services can be arranged by Magellan staff, in consultation with the MagE group, as is practical and desirable.
Any internal failure of the CCD camera or any failure of the spectrograph optics will probably require the intervention of the support group in Pasadena.
List the individuals at the home institution that are responsible for supporting the instrument:
Scott Burles, Steve Shectman and Ian Thompson
Christoph Birk, Greg Burley, Jorge Estrada, Jennifer Marshall
Describe the remote help that will be provided.
The instrument group are all available for assistance by telephone or email.
Marshall and Thompson will maintain the MagE manual. Contributions and comments are welcome from all mountain staff and observers using MagE.
A complete set of documentation for the MagE CCD cameras, including electronic schematics and mechanical details can be found on-line at http://www.lco.cl/telescopes-information/magellan/instruments-1/mage/. A hardcopy printout of the CCD schematics is kept in the CCD lab in the Astronomer Support Building. This documentation is supported by Burley and Thompson. The online page has copies of the manuals for the ion pump and convection vacuum gauge, and their controllers, as well as other major instrument components.
A copy of the schematics for the electronics control box is kept in the MagE storage cabinet in the Auxiliary Building. This documentation is supported by Estrada and the mountain electronics engineers (the main contact is Patricio Jones). A copy of the instrument mechanical drawings is also kept in the MagE cabinet.
As needed.
Lifetime of the instrument.
Describe the on-site help that will be provided:
Birk, Burles, Burley, Estrada, Marshall, Shectman, and Thompson.
In principal three days, though this depends on the severity of the problem and the near term scheduling of the instrument.
Describe the training that will be provided:
Patricio Jones has worked with the MagE team to develop the control electronics for the instrument, and has become familiar with the instrument in the process.
The Instrument Specialists will be trained to operate MagE during the commissioning run in November.
Future training would ideally bring the telescope operators up to the same level of familiarity, and introduce the instrument specialists and telescope operators to simple on-sky observations.
The instrument is provided with a wheeled cart for handling.
MagE can be moved on its cart under manual control from the assembly area into the dome. It will be mounted on the telescope's FP2 port using the overhead dome crane using the LDSS3 style lifting trunions.
MagE should not need to be removed from the telescope, but if it is, it should be stored on its cart with the mounting plate bolted onto the cart surface.
Shipping costs were paid by MIT. The instrument is installed at the FP2 focus of the Clay telescope, so this was a one-time expense.
None.
None.
None.
