BT4 Startup Checklist
BT4 Startup Checklist
Changing over from FANS
- Make sure that the small shield is installed
- Power down the monitor
- Remove the snout (will need the crane/george’s group)
- Check collimation
- Reatach bt-4 tas x-rail
- Attach the bt-4 tas monitor to power
- Repower the monitor (note the monitor is at 499.5 Volts, the detector is at 1276V)
SETUP TAS
- Check that the correct monochromator is in:
- d1h=25. This is necessary to give the monochromator room inside the drum to move in the z-direction. On the instrument rack immediately above the instrument computer, you will find the “goniometer drive” panel. This panel controls the x,y, and z motions of the monochromator. You will also find a table of values for each motion taped to this panel. Once you have executed step (a):
- Turn the “goniometer drive” panel knob to the desired direction to be moved (in this case “Z”)
- Place the “Drive” toggle in the direction of motion (+/-)
- Use “Slew” switch to drive the monochromator to the desired position
- Use the “Bump” switch when approaching the desired position to avoid overshooting, which can damage the monochromator
- Change the software value for the monochromator d-spacing using either dm=PG or dm=Cu in icp.
- Verify xpeek is started
- Check the zero for the detector 2 theta
- Use fndlam to get the correct two theta for the monochromator and to find the wavelength
- Rock the monochromator at several energies that you plan to use:
- fm 1,2,-.1,-2
- set 1= <value found>
- pz
- record Z01 in the log book
- repeat for several energies and record E, Z1, a1
- exit ICP by typing “ex”
- cd /bt4/cfg
- vim ZCOEFFS.CFG
- change the values for “slope” and “intercept” (the numbers in front of !z1coeff1 and !z1coeff2)
- save the file
- set z1=-99 (which is flag to use a linear correction for the zero point vs theta)
- pz and verify that z1=-99
- Align the analyzer
- Start prepare and icp in your directory
- Start statline
- Check which motors are free