Users manual for alignment of the x-ray optics of BL01B1
ver.2004/12/21
T.Uruga and H.Tanida (JASRI)
P. Fons (AIST)

Contents
1 Outline
2 Alignment of x-ray optics
Appendix

1 Outline
1-1 Arrangement of x-ray optics and measurement system
in Optics hutch︓ 1st slit (TCSLIT1) → 1st collimating mirror → Double crystal monochromator → TCSLIT2 →2nd vertical focussing mirror → TCSLIT3
in Experimental hutch︓ → Slit (4DSLIT) → 1st ionization chamber (I0) → Sample → 2nd ionization chamber(I)TCSLIT︓ 4 blade slit in optics hutch
4DSLIT︓ 4 blade slit in experimental hutch

1-2 Outline of alignment
The major operations carried out in the alignment of the x-ray optics are as follows:
Switching of the diﬀraction plane of the monochromator
Changing of the glancing angle of the mirror
The above operation slightly changes the beam height downstream of the monochromator.
Fine adjustment are done by measuring the x-ray intensity using the 1st ionization chamber in theexperimental hutch.
The height of experimental stage in the experimental hutch is adjusted to x-ray beam by scanning it in thevertical direction.
A ﬁxed beam condition is achieved by adjusting the rotation angle of the 1st crystal of the monochromatoraround the beam axis relative to the 2nd crystal.
The control program for the operation of the x-ray optics gives rise to the following x-ray beam conditions.
Low higher harmonic contamination (<10-5).
A ﬁxed beam position during XAFS scan passing through the center of 4DSLIT in the experimental hutch.
A focused beam in vertical direction (0.1-0.2 mm).
1-3 Outline of operation
First, the user must prepare the system for carrying out the alignment procedure.
Next, the user aligns the x-ray optics using a program written in LabVIEW from the control PC (Gaia)

automatically.
The user of the alignment software has only two types of interaction with the program:
Input parameters in setup window.
Click the OK buttonor the Move button.

1-4 Rules for operation
Each user group should have more than one BL01B1 expert during their beamtime.
The program operator needs prior approval (an operators license) to carry out alignment of the x-ray optics
from the BL01B1 beamline staﬀ.
The criteria for receiving a licence are as follows:
Knowledge of the arrangement and function of the x-ray optics of BL01B1.
An understanding what constitutes abnormal or dangerous situations during the alignment operation andhow to stop the procedure if required.
Users must ask permission from the BL01B1 beamline staﬀ to operate program from 17:30 to 9:30 on
weekdays and for all times on weekends.
2 Alignment of the x-ray optics
2-1 Preparations before starting the alignment program
Setup the system for x-ray measurement in the experimental hutch.
Select and ﬂow adequate and appropriate gas to the ionization chamber.
An adequate absorption ratio is 10-30 % for the I0 chamber and 80-90 % for the I chamber,respectively.
The absorption ratio can be calculated using the Excel ﬁle: I0_gas_absorption.xls in theDesktop
folder of the PC (Ganimede or next to Gaia).
Connect the HV cables from the ion chamber to the 1040 V on the HV supply (battery).
Check that the cable lengths allow for suﬃcient play during the vertical movement of the experimental
stage (on the order of 100 mm).
Properly close the experimental hutch.
Close the MBS (Main Beam Shutter).
Close the DSS (Downstream Shutter).
Check that the power is on for the pulse motor controller PM16C A in the equipment rack near the PC.
Check that the power is on for the stepper motor drivers: channels 0 to 5 (located under the PM16C A).
Restart the PC Gaia.
Ask the BL01B1 beamline staﬀ for the password.
Check the monochromator Bragg angle displayed on the encoder readout located above the PC Gaia.
If Error 3 is displayed, push the CLR button to display the correct angle.
2-2 Precautions during program operation
Beginner operators must read appendix B before starting the program.
2-3 Starting the program operation
Run the program Menu2.vi
Select the sub-program Netplane & Mirror from the pop-up menu.

Click Run button.
the Optics.vi will then open.

Click the Run button.

the red light will blink momentarily and then turn black.
The present status of the x-ray optics is displayed on the User Setup Window.

2-4 Input of parameters for the x-ray optics in the User Setup Window
The user is allowed to set parameters in the User Setup Window. Don't change any parameters in the othersub windows.
Set the monochromator parameters.
Select diﬀraction plane (net plane).
.
Don't select Si(733) as this setting is still in development.
Input a Bragg angle for the monochromator near the absorption edge of target element.

Don't input a Bragg angle higher than 20 degrees in this program.
This limit applies only to this program. XAFS measurement can be done at angles higher than
20 degrees.
Setting parameters for the mirrors.
Input the desired glancing angle of the 1st mirror （in mrad）.

Adequate glancing angle of mirrors, θ (mrad), are calculated by follows
θ=(60/（Emax＋3))-0.15
Emax < 15 keV
θ=(50/Emax)-0.15
Emax > 15 keV
where Emax (keV) is maximum energy of XAFS scan.
In the case where the mirrors are not used (e.g. are not in the x-ray path), input 0 (mrad).
Input the same value for the glancing angle for the 2nd mirror as for the 1st mirror.

Set the focus position relative to the 4DSLIT (meters). The error in this position is less than 0.4 m.
Input 0.25 m when the sample is set just downstream from the I0 chamber.

Input 0.6 m when the sample is mounted on the 2-axis diﬀractmeter.
Input the desired slit widths for the 4 blade slit in the experimental hutch (4DSLIT)..
Input the vertical width of the 4DSLIT (height).
For a focused beam, the vertical beam size is 0.1-0.2 mm. In this case, input 0.8 mm (the defaultvalue).

Input a horizontal width for the 4DSLIT (width) appropriate for the sample being measured (min.=0.1mm, max.=10 mm).
Don't set the slit width lower than 0.1 mm due to limitations of the hardware.

The 4DSLIT width can be changed by another program (4DSLIT move) after the completion of the optics
program.
2-5 Start the program.
Click Start OK button
This program automatically then goes through the steps listed on the right side of the window.
A blinking red light indicates the active step.
A black light indicates a completed step.

Thewindow then opens.
Check the GUI on the x-terminal of the beamline workstation. If the GUI appears on the display,Click the OK button.

Thewindow then opens.
After checking the gas ﬂow to the I0 chamber, click the OK button.

Thewindow then opens.

After checking that the MBS and the DSS are closed, click the OK button.
It is necessary to close the MBS and DSS during the initial part of the alignment procedure to ensure that strayradiation does not damage components of the mirror and monochromator.
Red light blinks for a moment, and turns to black soon.
The present position of x-ray optics is saved in log ﬁle.
A new ﬁle folder for the log ﬁle is created under \c\user\BL01B1_data\Optics_log in User PC Gaia; thename of the folder is the present date.
the red light will blink momentarily and then turn black.
The movement speed of each axis is set to high speed.
The red light blinks.
Each x-ray optical component is sent to its target position at high speed.
All commands to move x-ray optics are sent in parallel.
Time to ﬁnish movement
Switching between Si(111) and Si(311)︓ 6 min
Switching between Si(311) and Si(511)︓ 2 min
Changing glancing angle of mirrors ︓ 5 min
After movement of the x-ray optics is complete, the elevation stages on which the x-ray optics aremounted are moved.

Thewindow opens.

The target position of the elevation stage is displayed in.

During movement, the present position of elevation stage is displayed inin real time.
The present position of elevation stage is also displayed on the TV monitor.
The elevation stage movse at high speed until 2 mm from the target position, and then change slow
speed .
In the case of an emergency,
First, click emergency stop button.
Then call the BL01B1 beamline staﬀ.
Example emergencies include:
The elevation stage moving in the direction opposite to the target position or going
through the target position.
Noise from motor gear or similar problem.

the red light will blink momentarily and then turn black.
The speed of the x-ray optics is changed to the intermediate speed setting automatically
Red light blinks for a moment, turns to black soon and have peep.
The range of current ampliﬁer is set to 10^-7 automatically.
The beep is normal, don't worry about it.

Thewindow opens.
Open the MBS, and then the DSS.
Click the OK button.
Using the x-ray beam, the optics are precisely aligned by monitoring x-ray intensity using the I0 chamber.
the red light will blink momentarily and then turn black.

window opens.
TheIn this step, the monochromator is roughly adjusted to have the maximum diﬀracted x-ray intensity.
Click the OK button.
キャンセル means cancel.
A rocking curve measurement using the stepping motor is now carried out.
It takes 20-30 sec before starting rocking curve scan starts.

After the rocking curve scan completes, thewindow opens.
Check the rocking curve proﬁle.
In the case of both sides of the half maximum are in the scan range, the scan ﬁnished successfully.
If so, click the Move button. It takes 20-30 sec before the monochromator moves to the center
position of rocking curve.

If one or both sides of the peak are not in the scan range, rescan with the appropriate range. When
ready click the Scan button.
After this step, monochromator has been roughly adjusted to have a maximum in diﬀracted x-ray
intensity, but the position is only approximate due to the backlash of the stepping motor.
the red light will blink momentarily and then turn black.

Thewindow then opens.
In this step,the monochromator is precisely adjusted to have the maximum diﬀracted x-ray intensity.
Click OK button.
A rocking curve measurement using the piezo actuator is now carried out.

After the rocking curve scan completes, theAfter checking if the scan ﬁnished successfully, click the Move button.

window opens.

the red light will blink momentarily and then turn black.

window opens.
TheIn this step, the rotation angle of the 1st monochromator crystal around x-ray axis, Δα, is adjusted to beparallel to the 2nd crystal.
Click the OK button.
The horizontal beam proﬁle is measured by scanning the 4DSLIT in the experimental hutch.

After the scan, thewindow opens.
If the 1st crystal and 2nd crystal are perfectly parallel, the horizontal beam position is at the zero position.
The misalignment in Δα is calculated from the observed horizontal center of the x-ray beam and shown in theabove window.
After checking scan ﬁnished successfully, click the OK button.

After the Δα movement,opens.
If α<-10 or 10<Δα,a rescan of horizontal beam proﬁle is needed. If so, click the OK button.
If -10<Δα<10, click cancel button, キャンセル (in Japanese).
Repeat this step until -10<Δα<10.
After this step,
A ﬁxed exit beam condition is achieved.
The X-ray beam position is at the center of the 4DSLIT in the experimental hutch.
the red light will blink momentarily and then turn black.
In this step, the rocking curve is remeasured to adjust the 1st crystal position due to changes induced by theΔα movement.

Thewindow opens.
Click OK button.
A rocking curve measurement using the piezo actuator is performed.

After the scan, thewindow opens.
After checking that the scan ﬁnished successfully, click the Move button.
the red light will blink momentarily and then turn black.

window opens.
TheIn this step, the stage for mounting the measurement system and sample in the experimental hutch isadjusted to match the height of the x-ray beam.
Click the OK button.

After the scan, thewindow opens.
After checking that the scan ﬁnished successfully, click the Move button.
After this step, the x-ray beam is at the center of 4DSLIT in the experimental hutch.

the red light will blink momentarily and then turn black.
In this step, the width of the slits in the optics and experimental hutches are set to the target value.
It takes 1-2 min to complete the movement.
the red light will blink momentarily and then turn black.
The speed of mirrors and slits are set to the middle speed.
the red light will blink momentarily and then turn black.
The last position of x-ray optics is added to the log ﬁle.
If there is any trouble with x-ray beam condition, beamline staﬀ will check this log ﬁle.
2-7 Operations after completion of the program
At the end of the program, Optics.vi
Run button

turns toThe stop buttonshows following status.

.

turns to.

All the steps in the right side column are indicated in black.
After checking the normal completion of the program, carry out the following operations.
Close all the windows opened during program by using the close button.

Appendix A
Restart operation of X-terminal of beamline work station
This description is based upon the "How to use beamline work station" manual http://okutsu.spring8.or.jp/blcntl/Man_GUI/cde/cde.html.

These operations are done on the X-terminal of the beamline work station, not on the PC.
Stop the GUI.
Click the main button, メイン, above theThebutton on the front panel.

window opens.

Click close GUI button,.

Click clear buﬀer button.

Restart the GUI by clicking main button.
It takes 10 s to ﬁnish the restarting of the GUI.

Appendix B
Basic operation for the program.
PointsThe operator must check at each step in the program whether there are problems during operation.
When something make a noise in the optics or experimental hutchs, stop the program by clicking on
as soon as possible, and call the BL01B1 beamline staﬀ.
the stop button
When changing the parameters in setup window during the operation of program, click the stop
button in the main window or click the cancel button in all the steps described below.
Conﬁrmation windows
After checking points described below, click the OK button or the Move button.
There are three checking window in this program.
For a window asking whether or not to do the next scan, click the OK button.

For a window asking for the status of instrument, click the OK button after checking the status of theinstrument.
For a window asking to move or scan instrument,
Check the measured curve proﬁle.
When both sides of the half maximum are in the scan area, the scan ﬁnished successfully. Clickthe Move button.
If this is not the case, rescan after changing scanning range to the appropriate value. Whendone, click the Scan button .