For the TSSs; a summary of important issues:

• Always remember to close the shutter at the end of the night or when you have finished using Michelle.
• Close the shutter immediately if the outside humidity is 80% or higher.
• Disable the array at the end of the night or when you are finished using Michelle.
• If the chop throw changes, you must click the fast guider button to resize the draw window.
• After slewing, don’t turn on guiding until the telescope is in chop beam A.

Summary of instructions

• Type “michelleMenu &” on Hokulea
• Select “mich_oper screen”
• Enable the array from the mich_oper DM screen
• Select “WFG serial console (only)” from the michelleMenu screen
• Select “CCS serial console” from the mich_oper DM screen
• When running down, disable the array and close the shutter from the mich_oper DM screen

Running the relevant DM screens

Log onto Ohi or Hokulea as observer and type “michelleMenu&“. This will bring up the following window:

In theory, there is only one DM screen you need to run in order to observe successfully with Michelle. However, we will describe a few others in case they are needed for troubleshooting. At the very minimum, you will need to run the mich_oper.dl screen which is launched by hitting the “mich_oper screen” button in the above menu. The following will launch:

Enabling the array: At the beginning of the night, or when Michelle is about to be used for the first time, you must enable the array using the “Enable” button. The array control state will turn green from yellow, and the channel A & B temperatures will rise. Remember to disable the array at the end of the night or when you have finished using Michelle.

Closing the shutter: The Michelle shutter, situated in the warm calibration unit, is essential for the safety of the KBr window since it’s hygroscopic. Although the shutter will open automatically when you run the first Michelle sequence, you must remember to shut the window when you have finished using Michelle, if the outside humidity reaches 80%, or at the end of the night. To do this, simply click on the “flat/cover” button and then hit “START”.

Although the above describes the bare minimum needed to run Michelle, it is recommended that you also run the STATUS (see section 2) screen and that you also run the WFG and CCS serial consoles (see section 3).

Other useful DM screens

CCS status: The mich_oper DM screen can be used as a starting point to launch a variety of useful screens. Probably the most useful in order to monitor the status and Health of the Michelle mechanisms is the CCS Status display available by clicking on the “status” field in the mich_oper DM screen.

The above display shows the health and status of each mechanism. The START buttons will move the associated mechanisms to whatever is set in the individual mechanism DM screen. This means that quite often if you hit the START button, the mechanism will not move, so don’t be surprised if this happens. The grey field will be empty under most circumstances, but will show a red line if the mechanism has yet to find datum or will display an error message if the mechanism encounters a problem. “Running” does not mean the mechanism is moving, in fact it means that the mechanism is healthy. If the mechanism is moving, “Configuring” will be displayed in this column (plus one or two other messages depending on what the mechanism is doing at the time). Finally, the last column indicates whether the mechanism is moving or not. “IDLE” indicates the mechanism is still, “BUSY” means the mechanism is moving.  

The cryostat control system: The CCS display allows you to access individual DM displays for each mechanism, enter settings and move them. The display also allows you to quickly force the mechanisms to find datum but only after a reboot of the CCS. It is launched by holding down the right hand mouse button on the “other displays” field and selecting “CCS”.

After a reboot of the CCS, you can force the mechanisms to find datum by simply hitting the “apply” button. Each mechanism comes back with pre-determined settings after a reboot and this button simply sends a request to each mechanism to move to those settings. Since the mechanisms lose their reference position after a reboot, they are automatically forced to re-find their datum positions before moving to the desired setting. In normal operations, the mechanism will probably not move if you hit this button since each mechanism will probably already be at the correct setting.

NB. If the CCS has been rebooted, sending and executing a Michelle sequence in the OCS software will also result in the mechanism finding datum.

If, for some reason, you need to move an individual mechanism, say, for troubleshooting purposes, hold down the right hand mouse button over the relevant button and select the option you want. In most cases, this will be the first menu item, but buttons such as the detector and imaging buttons also give you a choice of two separate motors, For the detector these are the detector focus and translation, and for imaging this is the injector and extractor. As an example of what can be done, we’ll look at the grating DM screen.

NB. Before moving any mechanism using the individual mechanism DM screens, you should contact Tom Kerr for assistance. 

The top third of the screen simply displays the current settings, the bottom two thirds is where the action takes place. Most buttons and fields are probably obvious. The set wavelength buttons allow you to specify whether you are entering a wavelength or a mechanism step position. The datum search buttons will either force the mechanism to find datum (“force”) or allow the software to use its intelligence and decide whether the mechanism needs to find datum or not (“discretionary”). In just about every case, discretionary should be selected. The order selection buttons specify whether the software determines the grating order (automatic) or whether the user will specify it.

The grating can be selected using the 5 buttons on the left, with the wavelength (or step position) being entered in the brown field in the middle of the display and the order (if necessary) being specified on the right. Note that zero order cannot be selected and that a step position has to be entered manually for this. For the LowN grating, zero order is found at 4572 steps.

Power is automatically applied to the motors when the START button is clicked and the wl_power and drum power buttons will toggle. Note that you must hit the start button in order to move the gratings to the desired setting, they will simply sit at their original position if you do not.

Emergency stop: There have been occasions with other instruments that an observations is accidentally started with so many coadds that the integration will take several minutes, or even hours, to stop. Hitting the stop asap button in the sequence console doesn’t help, as the exposure will only stop after the set number of coadds have been done. The same is true for Michelle, although it is very unlikely such an observation will be created in the first place.

In case you do need to abort an observation in an emergency, you can do this via the Edict DM screen available by holding down the right hand mouse button on the “other displays” field in the mich_oper screen, and selecting “Edict”.

Simply hit the “abort” button to stop an integration (the button is not clear in Fig. 6, it’s the dark coloured button immediately underneath the observe button). NB. The effect that aborting an integration will have on the OCS software is not tested – it’s likely it will cause the OCS to go into an error state and that you’ll have to restart the OCS software.

The Edict and CCS serial consoles

Both Edict (the array control software) and the CCS (cryostat control system) have serial consoles which can be used to enter commands, monitor the software and be used to reboot the systems. Although not absolutely necessary, it is recommended that the WFG and CCS serial consoles are launched as a matter of routine since they are useful to have in case there are any instrument problems. Both of these consoles can be launched from the michelleMenu screen by selecting the “CCS serial console” and “WFG serial console (only)” buttons.

In normal operations, both consoles will display logging information and software settings relevant to both the CCS and Edict systems; therefore, if there is a problem of which the cause is not clear, you should glance at these consoles to see if an error message is displayed. Occasionally, you may also need to open all the edict serial consoles while troubleshooting to see if the slaves are reporting any errors. These can be launched using the “All Edict serial consoles” button on the Michelle Menu display.

If systems need to be rebooted via software, you can do this via the serial consoles. Type “reboot” in either the WFG or CCS serial console. Remember – rebooting in the WFG serial console will reboot Edict only, and rebooting in the CCS serial console will only reboot the CCS.

Please be sure to close all the serial consoles when you are finished with Michelle. 

Target Acquisition and Peakup

One big difference with Michelle in 04A compared to the last time it was at UKIRT is the ability to acquire a spectroscopy target in imaging mode without the need for a painful peakup. Although this hasn’t been fully tested yet, initial tests at night have been successful.

Instructions:

Run a normal spectroscopy sequence until you reach the target acquisition command. The sequence will automatically pause at this point. When paused, click on the MOVIE button, and the movie dialogue window will be displayed. Click on the START button, and after a few seconds, a chopped image will be displayed of your target area in the quick look tool.

When your target is identified, open the “pick object” dialogue window from the “View” menu on the quick look display. Then click on your target and hit the “Save/Append” button. The TSS now types “mpick” in the TCS, and the telescope will automatically slew to put the target on the slit. You may want to run another pick object, “Save/Append,” and mpick to ensure that the target is as accurately placed as possible.

When satisfied, end the movie by hitting the “STOP” button and then dismiss the movie display. Hit continue in the sequence console, and the sequence will now continue up to the break point just before the first observe. At this point, the instrument will have reconfigured itself back in spectroscopy mode, and you can, if you want, verify that the target is on the slit by doing a quick traditional peakup. If you choose to do this, select the movie dialogue window again and hit the start button. A spectrum will appear on the quick look display. Ask the TSS to move the telescope small steps left or right to center the target and then stop the movie and dismiss the window. You can then continue with the sequence and take data.

Pixel coordinates for use with MPICK

LowN Grating	MPICK Pixels
6-15 microns	142.7, 53.1

MedN1 Grating	MPICK Pixels
6-15 microns	142.7, 53.1
15.01 – 30 microns*	142.7, 53.1

MedN2 Grating	MPICK pixels
6-7.5 microns	142.7, 53.1
7.51 – 8.3 microns	140.9, 56.4
8.31 – 9.15 microns	145.3, 56.1
9.16 – 10 microns	144.1, 56.2
10.01 – 10.9 microns*	141.2, 52.6
10.91 – 12.1 microns	142.3, 55.2
12.11 – 13.1 microns	142.7, 53.1
13.11 – 15 microns	142.7, 53.1
15.01 – 30 microns*	142.7, 53.1

Echelle Grating	MPICK Pixels
7.3 – 8.3 microns	140.9, 56.4
8.31 – 9.15 microns	145.3, 56.1
9.16 – 10 microns	144.1 56.2
10.01 – 10.9 microns	141.2, 52.6
10.91 – 12.1 microns	142.4, 54.9
12.11 – 13.4 microns	142.4, 54.9
17 – 17.8 microns*	142.7, 53.1
17.81 – 19.1 microns*	141.2, 52.7
19.11 – 30 microns*	142.7, 53.1

LowQ Grating	MPICK Pixels
15 – 30 microns*	142.7, 53.1