dac operation

Operation Procedures

13-ID-D Energy Dispersive Diffraction

Guoyin Shen, Last modified 3/26/99

Operation procedures for 13-ID-D energy dispersive diffraction

Operation Procedures MEDM MCA Scan Troubleshooting

The 13-ID-D is a station of insertion device beamline in the sector 13 at the APS.
Follow the link to refer the beamline parameters.

Content

Operation procedures
       Mounting DAC
       Energy calibration
       Angle calibration
       Beam line alignment

2. MEDM
        Open MEDM window
        Description
                 Beamline control
                 Experiment information
                 DAC motors
                 MCA electronics
                 Other electronics
                 Scan
                 User calc. etc.

3. MCA
Open MCA
Electronics settings

4. Scan
        Open scan window
        Setting parameters
        File

5. Troubleshooting

       No x-ray beam
       Tip misalignment
       Weak signal
       JCPDS card not responding in MCA

Motor controls

Operation procedures for 13-ID-D Laser Heating System

Operation Procedures Winspec/32 Temperature Measurement Troubleshooting

Content

Operation Procedures

1.1. Alignment of laser heating path with x-ray

1.2. Getting ready

                 Mounting DAC
                 X-ray position
                 Alignment of laser heating optics with x-ray
                 Turning on lasers
                 Winspec/32 setup
                 Temperature measurement software

1.3. In situ diffraction

Winspec/32
Temperature Measurement
Troubleshooting

1. Operation Procedures

Energy calibration
Angle calibration
Mounting DAC
Beam line alignment

Energy calibration

* Open MCA window by

----open an IDL window (Start>Program>IDL)

----under file>preference

----Set the proper working directory

----Just type mca in command line of the IDL window, you'll see

----Go to File>Foreground>Open Detector

----Type the name of the Detector (e.g., 13IDD:aim_adc1). Note that the detector name is case sensitive.

----In acquisition area, click Erase first, then click On.

----Refer MCA electronics for the proper electronics settings. Discuss with CARS's staff for proper energy range.

* Energy calibration

----Put Radiation sources (Ask CARS's staff for the location) in front of the detector.

----Clear all region-of-interest by clicking clear all button

----Set region-of-interest for each peak of known energy. (You may do so by click the middle button for the left cursor and the right button for the right cursor. You may also put the right names for each fluorescence lines, e.g., Ag ka).

----Go to Control>Calibrate Energy

----Check the energy values and then click Compute calibration.

----Check the result with Plot calibration error and Plot FWHM

----Click OK to accept

Angle calibration

Cross-hair

* Put a tungsten cross hair on the sample stage.
* Find the cross-hair with the ruby microscope. (!!The ruby microscope is set to always look the center of the rotation of diffractometer. So never adjust the microscope to find the sample. Instead the micrometers on the sample stage should be used for this purpose!!)
* Check rotation center
----Make sure the motors of X(m5) and Y(m3) are at zero position. Never set any numbers for these two motors since zero refers to the rotaion center of theta and 2 theta.
----When seeing the sample, set the micrometers on the sample stage to zero.
----Rotate Omega 180 degrees. If you still see the sample, the sample is at the center.
----If not, adjust the micrometers on the sample stage until you see the sample.
---------Read the micrometer values, and move half the distance back.
---------Then adjust the micrometers for the ruby-microscope to see the sample.
---------Repeat the step of rotate Omega.
* Make sure the photodiode is in the position (beside the tip).
* Slide in the detector stage (the Shineeburger stage).
* Move 2-theta to 10 degrees, so that the photodiode can "see" the x-ray.
* Access x-ray.

Scan

*Refer Scan for setting up the scan procedure
* If clean-up slits are used, this is a good time to check the alignment of clean-up slits

* Scan Vertical Slit Y Pos. (M9)
* Locate M9 to the center, and set the number to the half of the slit width with minus sign. (e.g., if slit width is 0.010, set this motor -0.005).
* Repeat for the Horizontal Slit Pos. (M12)

*Scan the cross hair.

* Scan Y, motor3, find and move to center.
* Move 0.050 mm away from the center before scanning the X-direction.
* Scan X, move to the center in X-direction.
* Move 2 theta to the desired angle.

*Go to MCA window, take measurement.

*Set region-of-interest (ROI) for one diffraction line or tungsten fluorescence line.

*Back to Scan, use roi to scan the tip X-position (m7).

Move the tip position to the center.

*Now collect a good diffraction pattern from tungsten wire (10 microns in diameter).
*Observe all diffraction lines.
*In MCA window, go to Display>JCPDS

JCPDS card JCPDS card

Click Material, pick the proper material and check the angle and pressure values. In this case, pick tungsten.
The green lines from JCPDS should show in MCA window. Check if the lines match the diffraction peaks.
Click add ROIs in JCPDS display window. All diffraction peaks will be set as ROIs.
Go to Control>Calibrate 2 theta

Click Compute 2-theta, observe the values of two-theta diff.

Then either reject or accept by clicking yes/no in the second colume.
Click OK to accept.

1.3. Beam line alignment

Beam line alignment is usually done before experiment. Only do this when serious problems occur. At the same time, report to CARS's staff before doing any adjustment.
Alignment of Pinhole and FOE slit (both located in ID-A)

* Record Pinhole and FOE slit position
* Set FOE slit width to about 0.1 mm in both directions
* Set a detector (e.g., photodiode) at the output of Be window in the ID-B, put a Al-plate in front of the detector for protection
* Scan FOE X-pos and Y-pos, fix Pinhole positions
* Move FOE X-pos and Y-pos to the center of Pinhole
* Scan Pinhole and FOE slit together to see the position of undulator beam
* Move Pinhole and FOE slit to the peak position
* Typical values for FOE slit are 0.200 mm in both directions
* Record Pinhole and FOE slit position

Alignment of the table top slit to x-ray

The positions of the table top slit have been internally aligned to the rotation center of the two-circle diffractometer. So the table top slit is aligned to the beam by scanning the Base Table.

*Open table top slit width to 0.100 mm in both directions
* Set a detector (e.g., photodiode) for detecting x-ray beam intensity after table top slit (usually it is pre-set)
* If clean-up slit used, remove the clean-up slit now.
* Reduce the vertical slit width to 0.02 mm.
* Scan Base Table Y-pos (this consists of three individual motors)
* Find and locate the peak position
* Do the same for horizontal direction

(Check if the rotation center is at x-ray beam)
* Set a cross hair at rotation center
* Scan the cross-hair both directions
* If off by more than 0.050 mm in horizontal direction, the same amount of distance needs to be corrected by moving the Base table and the position of the horizontal table top slit.

(Reset table top slit positions)
* Reset the 'vertical slit pos' to the half of the slit width with negative sign
* Reset the 'horizontal slit pos' to the half of the slit width with negative sign

Table top slit

A slit needs to fix three things: position, rotation (tilt), and width

*position is defined by the x-ray beam position, as described in alignment of table top slit to x-ray
* rotation can be defined by scanning the rotating motor
* width is calibrated by scanning the width from, say, 0.05 to -0.03 mm (use absolute scan). A slit width of zero can be defined in this way.

2. MEDM

                            2.1 Open main MEDM control window
                            2.2 Description
                          2.2.1. Beamline control
                                2.2.2. Experiment information
                                2.2.3. DAC motors
                                2.2.4. MCA electronics
                                2.2.5. Other electronics
                                2.2.6. Scan
                        2.2.7. User calc. etc.

2.1 Open MEDM control window

Method One:

Click the shortcut MEDM 13-ID-D at desk top, you will have a MEDM window:

Method Two:

Go to Start > Programs > EPICS WIN32 Extensions > MEDM in the Start menu .

Note: Be sure to select Execute button in the MEDM.EXE popup!! Select each field by dragging the mouse in the corresponding button. Keep the left mouse button pressed when going to the next level of selections. The buttons will allow you to control various components of the DAC setup:

Click File, and Open the file named 13IDD_DAC.adl. (see below)

Click OK

This is the main control window called 13IDD_DAC.adl.

2.2. Description for MEDM window

Beamline Control: beam status, equipment protection system (EPS) status, beamline slits (FOE slits, FOE pinhole), undulator control.
Experiment Information: experiment information which will appear in every mca spectrum.
DAC Motors: essentially ALL motors for DAC operation.
MCA electronics: electronics for the multi-channel analyzer (MCA). Canberra amplifier, A to D converter (ADC), etc.
Other electronics: Stanford Research Systems (SRS) preamps (# 2 is used for photo diode input and output); Scaler (used for clock and photo diode readings); Keithley.
Scan: used for scanning any positioners (a motor, a cmpound motor, or anything that can be "moved").
User Calc.: For inputting the user calculation formular

2.2.1. Beamline Control

By click Beamline Control at the main MEDM window, it will show:

wpe2.jpg (24294 bytes)

storage ring status

13-ID status and BPM

13-ID BPM details

Undulator Gap Control

Vaccum and EPS

The green dots turn to red when any equipment protection system (EPS) fails and the beam will be disabled. Report any faults to CARS's staff

Beamline Motors

Slit width changes symmetrically. Up(+), Down(-), Outboard(+), Inboard(-)

Coordination convention (Right hand rule): X Outboard(+)/Inboard(-), Y Up(+)/Down(-), Z Downstream(+)/Upstream(-).

Generic Searial Record

2.2.2. Experiment Information

To be added

2.2.3. Motors

From main MEDM window

there will be several motor groups from the icon Motors

The following are MEDM widows for controlling each motor group.

Note: Coordination convention (Right hand rule): X Outboard(+)/Inboard(-), Y Up(+)/Down(-), Z Downstream(+)/Upstream(-).

To view more details, for example,

wpeC.jpg (79580 bytes)

Click More for view/change limits etc.

Click All for view/change all details.

Click scan parameters for view scan parameters

2.2.4. MCA Electronics

Note: this is NOT used for collecting data from the MCA, but to set up the electronics.

wpeD.jpg (22110 bytes)

Canberra Spectroscopy Amplifier [xxlcbAmp.adl]:

Canberra ADC [xxclbAdc.adl]:

MCA Regions of Interest [mca_ROIs.adl]:

MCA Plot [mca.adl]: This is not used normally. Refer MCA for data collection and plot.

2.2.5. Other Electronics

wpeE.jpg (21718 bytes)

SRS Current preamplifier 1 is for the photo diode (beam intensity monitor),

SRS Current preamplifier 2, not used,

Scaler for clock and photo diode readings,

Keithley 2000 DMM, not used,

Digital to AC, not used.

SRS current preamplifier 1 [SR570.adl]:

You can change the settings on the SRS preamps remotely by clicking these buttons. Especially, if the photo diode readings are around 640,000, it means it is saturated. You should (1) reduce the beam, and (2) change the sensitivity (say, from nA to microA).

Scaler [scaler_full.adl]: for monitor the photodiode reading

2.2.6. Scan

Method One:

open an IDL window (Start>Program>IDL)
under file>preference

Set the proper working directory
Under command line, type widget_scan

Description:

scan type: scaler for photodiode
roi for MCA

scan dim: 1-D
2-D

# motors: up to 2 motors

Count time: e.g., 0.3 s for photodiode
1 or longer for roi

Total time: the calculated time for the whole scan

Motor name: motor name can be got by clicking the middle button on the motor in MEDM window
or check the list posted in the beamline

Scaler PVname put 13IDD:scaler1 for photodiode

# scaler: change to 2

Plot: click the plot for time off

MCAPVname: For roi scan, put detector name 13IDD:aim_adc1 (for ROI change each time, hit return in this box to refresh)

Back. width: change to -1 (No background correction)

For ROI scan, click the plot for photodiode off.

Timing mode: Live

Scan filename: put the proper name. If ending with a number, the increment scan will be saved.

Start scan to start. After scan, all motors will move back to the initial positions.
You may abort scan by clicking the Abort scan at any time. All motors will move back to the initial positions.

Method Two

Used for scanning any positioners (a motor, a compound motor, or anything that can be controlled to "move") while watching any detectors (time, intensity of the photo diode, ROIs in the MCA, or anything that can be measured).

Scan parameter window

Enter the following fields:

Positioners 1 can be loaded for any positioners either by typing the positioner’s PV name, or by clicking the scan button on a Positioners Window, e.g. see for example the DAC Huber. Dummy positioners can be used by clicking on the "USE DUMMY" button. This allows you to perform multiple MCA data collections while watching temperature or other parameters, without moving any positioners.

2, 3, and 4 are for 2-D, 3-D, and 4-D scans
Under the positioner "More" button, there are two options.
"Positioners 1 – 4" allows you to enter up to four positioner for each scan.
"Positioner Waits" allows you to set up positioner waits (our default is Alldone)

Det. triggers

1: 13IDD:Scaler.CNT VAL:1.0

2: not used

Detectors 1: the clock (13IDD:Scaler1.T)

2: the photodiode (13IDD:Scaler1.S2)

3: not used

4: one ROI (for example) (13IDD:aim_adc1.R1)

Under "More"> "Detectors 1-15", you can enter up to 15 detectors.

Under "More"> "Detector waits", set up detector waits:

2.2.7. User Calcs, etc.

User Transform 1 [userTransform.adl]

2. Data Catcher

lets you catch scan data

Telnet to CORVETTE using HOST ACCESS under Exceed6 on YourMachine (OUTBACK, MIATA)

Log onto CORVETTE with username DAC_USER and the appropriate password (get Password from CARS's staff). Since CORVETTE is a Unix box, all commands are case sensitive!

Enter setenv DISPLAY outback:0

Load IDL (just type idl)

Run the data catcher under IDL: IDL > catcher_v1.

After the data catcher is loaded, run Process Variable Setup (PV Setup) by clicking on the setup button and then choose scan.

Enter 13IDD:Scan1 in the field of "SCAN 1D Pvname". For 2D scans, enter the second PV name in the field of "SCAN 2D Pvname".

Scan 2 – for 2-D scans

Scan 3 – for 3-D scans

Scan 4 – for 4-D scans

Under "Print", you may chose to print out your scan results (ASCII) to a printer or save it in a file – be sure to select the correct scan # to save.

3. MCA

3.1. Open MCA

3.2. MCA electronics

5. Troubleshooting
5.1. Tip misalignment

Photos

The 13-ID-D station, May'98

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The control area, May'98

wpe4.jpg (46236 bytes)

Inside the station, May'98

Setup

wpe7.jpg (70774 bytes)

Two circle diffractometer installed in the 13 ID-D

Motor Control

All step motors are controlled by EPICS system. Use MEDM to operate all motion controls.

When add motors, be sure the current settings and holding voltages on the stepak are right for specific motors.

When remove motors, be sure to set the current and holding voltage to minimum and turn 'motor' off on the front panel of the board.

Operation procedures for 13-ID-D Laser Heating System

Operation Procedures

Alignment of laser heating path with x-ray

Getting ready

Mounting DAC

X-ray position

Alignment of laser heating optics with x-ray

Turning on lasers

Winspec/32 setup

Temperature measurement software

In situ diffraction

Alignment of laser heating path with x-ray

This procedure is done normally before experiment. Only do this when problems observed or to confirm the alignment.

Put a cross-hair at the rotating center; (refer Center for centering procedure, make sure motors (X, Y) are at zero position.)
Observe the cross hair by two laser heating microscopes
The monitors for these two microscopes are located on shelves in the control area. The cross mark on the monitor is aligned to the spectrometer for the temperature measurement. So do not erase the cross mark.

* adjust focus by the micrometer at the downstream side to reach the image of the cross-hair
* adjust the upstream focus by a DC motor
----The control box of the DC motor driver is in the control area. Caution!!! Do not over drive! This may hit the Be mirror and damage the alignment.
----When the previous microscope position was corresponding to DAC, the upper black button on the control box should be pressed. Use Caution!!!
----When the previous microscope position was corresponding to pinhole or/ cross-hair, the focus should be very close and you should see the image. If not, something else is wrong. Do not adjust the DC motor in this case.

You may align the cross-hair to the cross mark on monitors by adjusting the Be mirror. Refer Laser motors for control.
Replace the cross-hair by a 25-microns (in diameter) pinhole
Use Be mirror to optimize the alignment
Replace the pinhole by a Pt-foil
Turn on He-Ne laser. The He-Ne laser is located behind the first mirror receiving the laser output.
Observe if the red He-Ne laser can be seen on screen. If not, contact CARS's staff.
Turn one YLF laser on, refer Turning on lasers.
Increase laser power until you see glows.
Adjust the glow spot to the cross mark on screen by upstream/downstream laser mirror. (!!!Not the Be-mirrors!!!)
Turn on the other YLF laser, check the alignment. If not, contact CARS's staff. Do this only you plan to use two lasers.

Getting ready

2.2.1. Mounting DAC

* Remove two laser heating microscopes. Before doing so, always make sure the tip is moved away. Otherwise the tip will be touched by the downstream Be-mirror. (It is a disaster, isn't it?)
* Make sure the Omega has the right orientation for DAC. Never rotate Omega more than 5 degrees with DAC on the sample stage.
* Put DAC on the sample stage.
* Use the ruby microscope to find the sample.
----Use only the sample stage micrometers and Y-motor to find sample. Make sure X- and Z- motors are at zero position.
* Make diamond thickness correction
----thickness of diamond x 0.59 = the amount of correction
----set the corresponding micrometer to zero
----move the DAC toward the ruby microscope by that correction amount
* Take the DAC off the sample stage. (This is important.
* Rotate Omega stage 90 degree relatively. Make sure the right side of DAC faces toward downstream. (A photo will be shown here for reference, right now, please contact CARS's staff for the right side).
* Put DAC on the stage again. Now the DAC loading axis is approximately parallel to the x-ray beam.
* Move the tip back in.
* Scan sample position by using photodiode.
* Go to MCA window, take acquisition.
* If there is signal, set region-of-interest on signal. If no signal, set the whole spectrum as region-of-interest.
----For weak scattering samples, you may move to the gasket position for stronger signals.
* Scan ROI for the defined region-of-interest using motor Z (along x-direction, m4). Refer Scan.
* Now the sample is ready for taking data.

1.2.2. X-ray position

Move the tip stage out. This is an important procedure before moving in laser microscopes.
* Move in two laser heating microscopes.
----Before pulling in the microscopes, release the springs at the inboard side first.
* Put illuminating lights for both upstream and downstream sides.
----The light consists of a beamsplitter and a light source
----These two lights can be controlled independently by switches on the control panel outside the hutch.
----Note: illuminating lights are only used for viewing. For temperature measurement, these MUST be removed since the system calibration was done without the beamsplitter in the path.
* Adjust focus
----adjust focus by the micrometer at the downstream side to reach the image; in this case you move objective away from sample.
----adjust the upstream focus by a DC motor
-------The control box of the DC motor driver is in the control area. Caution!!! Do not over drive! This may hit the Be mirror and damage the alignment.
-------When the previous microscope position was corresponding to DAC, the focus should be very close. Just adjust with Caution!!!
-------When the previous microscope position was corresponding to pinhole or/ cross-hair, use lower black button on the control box to reach the focus..
* Adjust Be mirrors to move the center of the gasket hole to the cross mark on the monitor. Refer Laser Motors.
* Turn off the illuminate lights.
* Access x-ray

1.2.3. Alignment of laser heating optics with x-ray beam

* Following the procedures in x-ray position above.
* Change sensitivity of CCD camera
---- Turn off the hutch room-light.
---- Press Prog down on the front of the control box for a few seconds until a menu showing up on screen.
---- Choose Camera Set Up, (press the middle button to accept)
---- Change shutter setting from 1/100 to off
---- Change Sens Up to desired values, usually to 32x auto.
---- Press Prog twice to exit menu.
---- Normally we'll see the x-ray beam on screen
---- Adjust Be-mirror to align the x-ray beam to the cross mark. Refer Laser Motors.
---- Do the same thing for the other side.
* Now the x-ray beam is aligned with the temperature measurement system

1.2.4. Turning on lasers

You have to be a qualified user before working with YLF lasers. Contact CARS's staff for safety training and eye exam.

You need to read SOP posted on the door of 13ID-D and sign the user sheet. Contact CARS's staff after doing all these.

Laser
* Get keys from CARS's staff.
* Turn on the key switch by 90 degrees.
* Press green button (hold for 2-3 seconds) for cooling water.
* Press Lamp On button (hold for 2-3 seconds).
* Adjust the current control knob to 32 A.

Interlock
* Press Interlock Set.
* Press panic button (the red button beside door) while walking in/out the hutch. (Otherwise the interlock will be defeated.)
* Press Shutter enable button on the laser control box.
* Now the laser is accessible by just pressing the shutter on the control box.

Caution
* After turning off shutter, always reduce the laser power first.
* The laser power is monitored by a photodiode. Use the volt-meter beside the upstream monitor for laser power. Refer Graph below for values.
* If you are not sure the power level, put the beamstop (the power meter) at the output (see photo, in process). Then turn on the laser and check the power level.
* Reduce the power if necessary.

1.2.5. Winspec/32 setup

Refer Winspec/32.

1.2.6. Temperature measurement

Refer Temperature Measurement

In situ diffraction

* The system is ready for in situ diffraction after following Getting ready
* Plan your experiment. This may be a good time to discuss with CARS.s staff about your plan.

Winspec/32

Click the shortcut of Winspec/32 in the desktop.
---- You can also open Winspec/32 by follow: Start>Program>Princeton>Winspec.
Go to Setup>hardware>controller camera.
Check/Set parameters as shown

Under Cleans/Skips menu
Check/Set parameters as shown

Go to Acquisition>Experiment Setup

Use Save/Load for loading the setting file. Contact CARS's staff for the file name.
Use Data File to name the files to be saved.

-----The computer at upstream side is for upstream side temperature measurement

-----The computer at downstream side is for downstream side temperature measurement

-----Make sure to name files which can be recognized the side and other conditions.

The background file can be put into the Data Corrections.
Intensity and wavelength are calibrated. Contact CARS's staff for proper files.
Click OK to accept.
Minimize Winspec/32 window.

Temperature Measurement

Click the shortcut at the desktop: Run.exe. It may take a few seconds.

Select a Standard: (contact CARS's staff for file name)
For temperature measurement, just click Run…

This program can also used for temperature calculation
Just Open a Image File, and click Temperature Calculation

The temperature file is saved as Your filename plus ".tem"

Laser Motors

Pico motors
The control box for all pico motors is in the control area. There are 8 switches for controlling 8 different motors.
Important!! before moving the pad, always check the switch position.
Refer the sheet below (also on the top of the driver) for each motors.

Driver No.	Function	PAD-A	PAD-B	PAD-C
1	Upstream Be Mirror	Vertical		Horizontal
2	Downstream Be Mirror	Vertical		Horizontal
3	Upstream Laser Mirror	Vertical		Horizontal
4	Downstream Laser Mirror	Horizontal		Vertical
5	Not in use
6	Not in Use
7	Not in use
8	Laser Power Control	TEM01		TEMoo

Oriel motors

There is one Oriel DC motor for focus adjustment at the upstream side. Use caution when using this motor for the objective position
is very close to the Be mirror.
* The microscope is usually set up for a pinhole (or cross-hair) at the rotation center.
* If you replace the pinhole (or cross-hair) by a sample (e.g., a Pt foil for test heating), only adjust the micrometers on sample stage.
* When you need to correct the thickness of diamond for DAC sample, only use the lower black button on the control box.
* When you want to get image for the pinhole (or cross-hair) at the rotation center while the microscope is set for DAC,
use upper black button on the control box. Stop moving the motor as soon as you have the image. Do not over drive in this direction!

Troubleshooting

No x-ray beam
Tip misalignment
Weak diffraction
JCPDS card not responding in MCA

1. No x-ray beam

Check if the station (13 ID-D) has been searched. Then check other stations (ID-A, B, C).
If all searched, check EPS.
Go to main MEDM control window

Go to Beamline Control>Vacuum and EPS

If there is red dot, report to CARS's staff.
If there is smaller red dot with green around, just press Reset to clear the fault
If stations all searched, EPS is OK, then read the panel outside 13 ID-A (facing to ID-B). Report to APS floor coordinator if observed any error.
Floor coordinator can be reached by paging (4-0101).

2. Tip misalignment

If the tip is heavily touched, click Tip Alignment
The following is for optimizing the tip position.
* Put a cross-hair, find the rotation center
* Scan the cross hair, the x-ray position should be close to the center within 50 mm. If not, refer slit control.
* Move the cross hair 50 microns away vertically.
* Horizontal scan, put at x-ray beam.
* Go to MCA window, get diffraction.
* If there is signal, set region-of-interest on signal. If no signal, set the whole spectrum as region-of-interest.
* Scan ROI for the defined region-of-interest using Tip X-motor (m7). Refer Scan.
* Move tip to the optimized position and take diffraction measurement.
* Do new angle calibration. Angle calibration should be done each time when tip is moved.

Tip Alignment

* Put a cross hair at the rotation center
* Scan cross hair. You should find the x-ray beam very close to the cross-hair center. Otherwise contact CARS's staff.
* Take the Ge-detector down.
* Move 2-theta to zero degree.
* Put a photodiode behind the Huber slit.
* Move Tip up (Detector-Y Pos.) by 40 mm. Before doing so, check if there is potential problem.
* Scan 2-theta motor, e.g., using (-0.5 to 0.5) degree range for scanning.
* Locate the center and set this value as 2-theta zero.
* Put a burn-paper in front of the Huber slit and make a burn point by x-ray.
* Move the Tip Y-direction back to the original position.
* Adjust the Shineeburger stage so that the Tip sharp point is very close to the cross hair. Use caution for this procedure.
* Now the cross-hair and the burn spot refer the x-ray beam path.
* Adjust the Tip by using two motor stages and two manual tilt adjusters to align according to the cross hair and the burn spot visually.
* Use x-ray to scan the Tip both directions, first X-Pos. and then Y-Pos.
* Now the Tip is aligned
* Move 2-theta to the desired position before putting the Ge-detector back on.

3. Weak signal

Weak signal could be caused by many factors such as:

Low scattering sample,
Preferred orientation, e.g., crystal growth during laser heating,
X-ray beam,
System alignment.

*X-ray beam

----When the clean-up slit is used, make sure the clean-up slit is aligned to the table top slit. This can be done by scanning the table-top slit position.
----Refer beam line alignment for the optimal x-ray beam intensity

*System alignment

----The sample position along the x-ray beam (i.e., motor Z-position) should be at the intersection of the x-ray beam and the tip collimation line. This position can be optimized by ROI scanning a signal along z-direction. When laser optics is in use, use caution because the scanning range is limited by the optics.
----Tip alignment

4. JCPDS card not responding

JCPDS display is still an on-going work. For now, JCPDS uses background in mca for display. When background is used for the other purpose (e.g., display a saved file), the opened JCPDS window will not respond.

Close the JCPDS window.
Go to the idl window that opened the mca.
Type retall.
Now open the JCPDS display.