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This agreement is between the Observatories of the Carnegie Institution of Washington (OCIW), representing the Planet Finder Spectrograph (PFS) instrument team, and the Magellan Consortium, representing the Magellan technical staff.
Information about the instrument is collected at http://www.ociw.edu/~crane/pfs/
PFS is mounted at the Magellan II East Nasmyth port, close to but not attached to the guider.
Regular secondary (original F/11 Gregorian).
PFS uses a dedicated, integrated guider that is mounted to the instrument. This guider controls the telescope guiding system.
The instrument weighs about 3200 pounds. It is 117 inches long and 70 inches wide when the handles for the caster jacks are removed. Sitting on its hard mount points, it stands 90 inches tall when handles on the top panel of insulation are installed.
There is one instrument electronics box mounted on the side of the instrument. There is also a dual-channel 48-volt power supply mounted on the nasmyth platform railing to power the CCD electronics. The slit viewing guide camera receives power from the guider CCD camera power supply. The two CCD's are controlled with two computers mounted in a rack in the telescope equipment room. MIKE uses two of the four identical computers in the rack, another is used by LDSS3, and the fourth is a spare for both instruments.
The MIKE data acquisition GUI can be run from either of the astronomer computers in the observing room communicating with the CCD control computers described in the previous section. At some point in the future the acquisition GUI will run on a dedicated instrument control computer located in the telescope equipment room. This computer will communicate with the CCD computer, the GUI will be run remotely from the astronomer's computer in the observing room.
A dedicated stand-alone control box is also located in the observing room. This box provides for remote control and encoding of the slit position, focus for the blue and red cameras, and control of the quartz and Thorium-Argon lamps. Control for these functions is also available at the instrument electronics box.
MIKE is not attached to the instrument guider, there are no special telescope or rotator balance issues.
No special baffles are used or required.
Cables to the instrument are: 110-V and communications lines to the electronics box from the control box in the observing room, two 48-volt lines from the CCD power supply to the blue and red CCD camera electronics boxes (saddlebags), and two optical fibers to the blue and red CCD saddlebags. The slit viewing camera has power, communications, and cooling lines. All of these cables are draped on the floor, and since the instrument is not connected to the guider no cable wrap is required.
Power and commmunications lines are required for the ADC stage. Cabling exists for the control of the insertion and removal of the ADC, and the control functions exist in the MIKE GUI, but new lines and control software will have to be added for the control of the ADC operation.
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, the iodine cell stage and the cell itself.
The CCD cameras consume 20 watts when the temperature control resistors are turned on full. The cameras consume about 15 watts at their present operating temperatures.
The slit viewing camera consumes 10 watts.
There is presently no ducting of heat generated by the instrument.
The two CCD cameras consume a total of about four liters of liquid nitrogen daily when in use.
The two LN2 dewars are down looking, and require filling once per day. Currently the cameras are filled twice on most days, once by the telescope operator at the end of a night, and once by the Instrument Specialist during the day. Time required is about 15 minutes if there is nitrogen in the supply dewar on the nasmyth platform. The nitrogen supply tanks on the nasmyth platform are refilled by the Magellan mechanical technicians or by the Instrument Specialists when no mechanical technicians are on the same shift, this takes about one hour per week.
Installing the instrument onto the nasmyth platform and aligning it to the instrument rotator is done by the Instrument Specialists and requires three man-hours of work. Connecting the instrument cables and fiber lines and the coolant hoses to the slit viewing camera takes one hour; typically these connections are made by an Electronics Engineer. Some installations require additional work. For example, a request for a rotation of the red camera to align the slit more closely with CCD rows, testing of the iodine cell, and special grating settings can add an additional two hours of work. The installation procedure is described on the Magellan engineering web pages.
Substantial additional time is required when MIKE is reconfigured from MIKE-Fibers to the regular MIKE installation. This process takes four people (two Instrument Specialists, one Electronics Engineer, and the visiting astronomer) half a working day. Note that a QE treatment of the blue camera is usually requested as part of the fiber installation (but not typically in the other direction, we are monitoring this situation).
Observatory staff will make the following tests on a routine basis:
1) Noise and linearity tests for the two dewars. There is an IRAF script called mike_gain.cl to do a full test based on a pair of milky flat and bias frames. These tests are made by the Instrument Specialists and should be scheduled at an installation and once every two weeks of routine use or unbroken period of installation on the telescope. The time required to take two milky flat and two bias frames, to run the script, and to document the results is less than one hour.
2) Monitor the QE uniformity of the blue camera. Problems are manifested in a patchy or scratched appearance of the flat field, and in some (all?) cases by an enhanced dark current. An archive of typical MIKE images will be made available on the LCO web site, including examples of normal blue flat fields, and flats with moderate and extreme QE uniformity problems. The quality of the blue flats should be monitored at an installation and once every two weeks of routine use or unbroken period of installation on the telescope. This can be done by the observer or by an Instrument Specialist. Visual inspection is adequate, and can be done in a few minutes.
A blue camera treatment to return the QE to normal is a lengthy operation, the procedure is described in detail below in this section. The entire operation can take up to 12 hours from the start of warmup to when the blue camera is cooled to its normal operating temperature. During this time, about three total hours of one Instrument Specialist's time is required and about 1/3 hour effort from (typically) an Electronics engineer to disconnect/connect the CCD camera cables and fiber line.
3) Present practice is for an Instrument Specialist to focus the two sides of the spectrograph when the instrument is installed, when the instrument configuration has been changed (for example, moving the gratings to get different wavelength coverage), or when the ambient temperature has changed significantly. This is a task the observer could do, a detailed writeup of the IRAF focusing scripts would be required. A full focus sequence for the two cameras takes two hours.
Instrument Specialist: Six hours per new MIKE run (instrument installation and alignment, focussing, and noise measurement). Add up to three hours if a blue camera treatment is required or a special instrument configuration is requested. Routine work approximately seven hours per week (two focus sequences, one noise measurement, and LN2 refilling). When a new or unskilled observer is scheduled to use the instrument the Instrument Specialist spends two to four hours in observer support, introducing the observer to the instrument and assisting in initial observations. Occasional additional work on the instrument electronics is required to help troubleshoot problems.
Electronics Engineer: In charge of maintaining/connecting/disconnecting the cabels and fiber lines to the CCD cameras and the cables and coolant lines to the slit viewing camera. Occasional work on the instrument electronics.
Instrument Scientist: Occasional consulting work to debug problems, to discuss the need and scheduling of a QE treatment of the blue camera, and to discuss the general health of the instrument with the instrument team.
Pasadena Staff (mainly Birk, Burley, Estrada, 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 Bernstein with assistance from Thompson.
See above.
1) Control GUI: the command GUI is launched in any xterm window on the astronomer's computer with the command "mike". An option exists to control the font size (as in "mike -h 14"). Complete details are found in the MIKE manual (link exists from the Magellan Instruments web page).
2) Cabling to the instrument:
a) two optical fibers connecting the two saddlebags to the ccd control computers in the dome equipment room.
b) two power cables to the dual output MIKE power supply mounted on the nasmyth platform hand rail.
c) coolant lines to the slit viewing guider camera.
d) power and signal cables to the slit viewing guider camera.
e) Two cables for focus control and one cable for slit motion control, both originating in the MIE control box located in the observing room.
f) Other cables stay with the instrument and are not disconnected from from the instrument unless it is being set up for MIKE fibers.
3) Pump down procedure: Normal dewar vacuum practices, final target pressure is less than 1e-6 on the vacuum pump electronic gauge.
4) Warm up procedure. The dewar should be warmed by letting the LN2 evaporate. If a faster warmup is required, the dewar can be removed from the instrument and the LN2 dumped. The warmup may be accelerated by blowing dry ambient temperature air into the LN@ chamber. The warmup MAY NOT be accelerated by leaking a small amount of air into the vacuum for either camera.
5) The following procedure should be used when the blue camera has to be treated to correct for QE non-uniformities:
a) Power down and remove power, shutter control and fiber cables from the CCD saddlebag. Remove dewar from telescope and dump the LN2.
b) Warm up dewar. The warmup may be speeded up by blowing ambient temperature air into the camera nitrogen tank.
c) Put the dewar on the vacuum pump and start warming the CCD with the halogen lamp placed as close as possible to the dewar window.
d) Once the dewar is warmed to ambient temperature (as measured by the temperature inside the LN2 can), remove from pump and fill with air (pure O2 does not appear necessary). Note that using air is only acceptable under dry conditions - do not attempt with humidity above 40% (can use pure O2 if conditions are too wet). Close the dewar vacuum valve.
e) Wait ~30 minutes while continue heating the CCD with the halogen lamp.
f) Return the dewar to the vacuum pump and continue with halogen lamp.
g) Once the dewar has pumped down sufficiently (the goal is better than 1.0e-6) the camera can be mounted on the instrument and cooled down with LN2. Connect the power, fiber, and shutter control cables, and power up the dewar.
These procedures are described on the Magellan Engineering web pages, these pages are the definitive source of the correct procedures for handling the instrument.
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 MIKE blue and red CCD cameras are shared with the 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 either of the MIKE blue or red cameras.
Instrument spares: The following spares are to be found in the MIKE cabinet in the telescope equipment room:
Shutter, ThAr and quartz lamps, focus motor, dial gauge, comparison lamps flipper mirror mechanism, flipper mirror controller, encoder potentiometers for both focus and slit position.
The MIKE general distribution email alias is mike lco.cl. The main contact individuals are
Rebecca Bernstein (rbernst umich.edu)
Christoph Birk (birk ociw.edu)
Greg Burley (burley ociw.edu)
Jorge Estrada (estrada ociw.edu)
Steve Shectman (shec ociw.edu)
Ian Thompson (ian ociw.edu)
CCD camera issues: Burley, Estrada, Thompson
Instrument performance: Bernstein, Shectman
Acquisition program performance: Birk, Burley, Thompson
All of the above receive copies of the daily reports when MIKE is used for observing. Birk, Shectman, and Thompson receive copies of all daily reports and can monitor work on MIKE during engineering or when it is not used for observing.
The mountain staff can service the instrument electronics box and data room conrol box. These control and display slit plate motion, calibration pickoff mirror motion, ThAr and quartz lamps, and the shutter. Pumping and cooling the dewar are routine activities to be performed by the mountain staff. The mountain staff are also qualified to treat the blue dewar, the decision to treat the dewar should be done in consulation with Thompson and Burley if possible. The external power supplies for the CCD cameras and the guiders are to be maintained by the local staff. The mountain staff may swap boards in the CCD saddlebags in the process of troubleshooting problems with the performance of the CCD's, 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's are controlled by computers mounted in a rack in the dome equipment room. The rack has four identical computers, three of these are used at any one time to control the MIKE dewars and the LDSS3 dewar. 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 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 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 MIKE group, as is practical and desirable.
Any internal failure of either 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:
Steve Shectman and Ian Thompson
Christoph Birk, Greg Burley, Jorge Estrada
Describe the remote help that will be provided.
The instrument group are all available for assistance by telephone or email.
Bernstein has been maintaining the MIKE manual with Thompson's assistance. Contributions and comments are welcome from all mountain staff and observers using MIKE.
A complete set of documentation for the MIKE CCD cameras, including electronic schematics and mechanical details can be found on-line at www.ociw.edu/instrumentation/ccd/MIKE.html. A hardcopy printout of the schematics is kept in the CCD lab in the Astronomer Support Building. This documentation is supported by Burley and Thompson.
A copy of the schematics for the electronics control box is kept in the MIKE storage cabinet in the telescope equipment room. This documentation is supported by Shectman and the mountain electronics engineers (the main contact is Patricio Jones).
As needed.
Lifetime of the instrument.
Describe the on-site help that will be provided:
Burley, Estrada, 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:
N/A.
N/A.
The Instrument specialists are familiar with operating MIKE in the process of focusing the instrument and in doing standard setups. 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 mounted on a cart with deployable wheels. The instrument is tilted on the cart by 30 degrees to minimize atmospheric refraction across the slit above an elevation of 50 degrees on the sky. The instrument can be moved on the cart under manual control on the platform and in the dome.
MIKE is normally mounted on the NASE port of Magellan II. When not in use it can be stored on the dome floor. The instrument is covered with plastic sheeting during bad weather.
N/A.
None.
None.
None.
