david martin high precision beamline alignment at the esrf ...david martin . high precision beamline...

David Martin High Precision Beamline Alignment at the ESRF

IWAA, Grenoble 3-7 October 2016

OVERVIEW

The ESRF has just completed the Phase I Upgrade programme.

The Phase I Upgrade programme was centered on the construction of a new generation of X-ray instruments and beamlines. 19 of the 30 public beamlines have been completely reconstructed or undergone major refurbishment. Part of this programme included the construction of 8000 m2 of new experimental hall premises with critical temperature and mechanical stability specifications.

IW2016 Grenoble - High Precision Beamline Alignment at the ESRF, David Martin

OVERVIEW

The Phase II Upgrade - Extremely Bright Source (EBS) - aims to dramatically increase the X-ray source brightness by decreasing the machine horizontal

emittance. To do this, the ESRF has chosen to redesign the machine lattice by significantly increasing the number of bending magnets.

This new design requires removing the existing machine and replacing it with a new one. This will be done between

now and 2020 with the bulk of the assembly and installation scheduled for 2018 to 2020.


OVERVIEW

We will concentrate on the successful Phase I Upgrade Beamline (UPBL) construction and installation programme:

• Centering on two specific example beamlines:

• UPBL7 ID32, and

• UPBL4 ID16

• And discussing several techniques that were used to align the beamline equipment to the required tolerances.

Following this Flora Yakhou-Harris (ID32) and Peter Cloetens (ID16A NiNa) will discuss alignment issues and science on their respective beamlines.


THE ESRF


A ESRF is composed of two main elements: • A particle accelerator that generates synchrotron radiation, and • Beamline(s) that use the synchrotron radiation generated by the

accelerator to study matter.

The linear accelerator (linac) accelerates the electrons from rest mass to 100 MeV

The booster accelerates the electrons from 100MeV to 6GeV

The storage ring keeps the electrons circulating at 6GeV for many hours

The 6GeV electrons produce synchrotron radiation in a tangential direction to the beam travel

NANO PROBE


The size of the focused x-ray probe spot depends on: • the source size, • the distance between the source and the focusing optics p, and • the working distance between optics and the experimental sample q.

At the ESRF p=150 m and q=0.05 m so q/p=3000-1 → theoretical probe size ~10 nm

0.1 mm

70 to 180 m

THE SCALE OF THINGS AND THE IMPORTANCE OF ALIGNMENT


e-

1 mm

A crystal is placed on the end of the pin with a stream of cool air coming in from the right. The X-ray beam arrives from the silver pipe and the camera images the crystal

http://www.dailymail.co.uk/sciencetech/article-2828699/Inner-beauty-world-revealed-Photographer-captures-amazing-crystal-structures-objects-reveals-created.html

THE ESRF SURVEY NETWORKS


Z

DiNi 12 Electronic Level

0.3 mm for 1 km 2 way levelling

AT401/402 Laser Tracker

XY and Z

Angles ± 5 μm + 6 μm/m Distance ±10 μm

ASME B89.4.19-2006 MPE

Leica Viva GNSS GS15 receiver

3 mm + 0.1 ppm post processing and long observations

XY

http://www.google.com/url?sa=i&rct=j&q=hexagon+metrology+AT401&source=images&cd=&cad=rja&docid=gih0wmSbAl2RLM&tbnid=nes_D6PlgmeCZM:&ved=0CAUQjRw&url=http://metrology.leica-geosystems.com/en/Press-Releases_1075.htm?id=4404&ei=uVx1UbGgMqGK0AWe0ICwBw&bvm=bv.45512109,d.ZWU&psig=AFQjCNF1lZ8cPYhJq78lRdQhKQLJFG_abw&ust=1366732326768408

Instrument stations

THE STORAGE RING NETWORK


e- 30 µ

m

20 µm

EX2 NETWORK


EX2 NETWORK UNCERTAINTY


30 µ

m

20 µm

ID32 NETWORK


ID32 – THE PROBLEM


ID32 – OPTICAL ELEMENTS


ID32 – HORIZONTAL DOUBLE MIRROR PARALLELISM


Side

Top Double Mirror

ID32 – HORIZONTAL DOUBLE MIRROR PARALLELISM


ID32 – HORIZONTAL DOUBLE MIRROR PARALLELISM AND ALIGNMENT


ID32 – VERTICAL DOUBLE MIRROR PARALLELISM


ID32 – MONOCHROMATOR


ID16 – MONO LAYER MIRROR (MLM)


MLM ID16A Mono Layer Mirror

X-ray beam

160 m lever arm

ID16 – MLM FIDUCIALISATION IN A CLEAN ROOM LABORATORY


ID16 – MLM ALIGNMENT IN SITU


Tie in the instrument (x,y,z) using the survey network

Align the mirror support references to their nominal positions

ID16 – NANO IMAGING BEAMLINE OPTICAL LAYOUT


Source Point 0 m

MLM 28.3 m 16 mrad

Horizontal and vertical KB Focusing mirrors

184.5 m

Sample 185 m 20 to 30 nm beam size

e- beam

X-rays are reflected and focused with mirrors at glancing angles less than 0.5 degrees → 9 mrad.

ID16 – NANOIMAGING BEAMLINE MONO LAYER MIRROR (MLM) ALIGNMENT


8 mrad 1.6 mm

This is the mirror surface seen by the beam when it is

tilted 8 mrad to the beam

This is the mirror surface seen by the beam when it is parallel to the beam

X-ray beam diameter ~1mm

ID16 – NANO IMAGING EXPERIMENTAL STATION


ANGLE AND DISTANCE MEASUREMENT


Determining an angle with distances is inherently less precise than auto-collimation

L= 0.2 m

U(D) = 10 µm U(D) = 10 µm

U(α) = 0.5 to 1 arc second (2.5 to 5 µrad)

PHASE II - EBS


The ESRF Phase II EBS presents many significant alignment challenges We will discuss some challenges related to the beamlines …

EBS AND THE BEAMLINES – THE PROBLEM

The new machine has a nominal design position. But the existing machine is not in its nominal position …

Nominal Position

+1.1 mm

-2.1mm

Horizontal

Nominal Position

+0.8 mm

Vertical

-1.2 mm

The simplest option is to align the machine in the position of the old machine …

Cell1 Cell32


31



The main problem is that there is uncertainty as to where the actual beamline axes are with respect to their expected positions?

Nominal beamline axis

Machine and alignment errors Long term movements

32

Source Point

Frontend Slit

Primary Slit



Measurements were made on selected frontend and beamline primary slits to determine the difference between actual and expected positions…

-1.20

-1.00

-0.80

-0.60

-0.40

-0.20

0.00

ID16

Port End

ID16 Straight

The nominal beamline axis is determined by the magnet positions

The measured beamline axis is determined by the slit positions


The standard deviation in the difference between the measured and expected primary slit positions was 0.63 mm.

This corresponds to a beamline angle uncertainty of 27 µrad at 1σ and implies alignment uncertainty of:

→ ±3.2 mm at 2σ at 60 m in the EXPH,

→ ±6.4 mm at 2σ at 120 m in the EX2, and

→ ±9.7 mm at 2σ at 180 m on ID16.

This means even if we align the new machine where the existing machine is, the photon beam will not necessarily be where it is today.


EBS AND THE BEAMLINES – MEASURES

We have decided the best way forward will be to …

• Ensure all FE slits are remote servo-controlled.

• Measure the all of the beamline FE and primary slits to calibrate the beam trajectory.

• Install a beam viewer on every beamline. The beam viewers will be fiducialised and in principle the position of the beam can be measured.

• It is planned to be able to steer the beam onto the beam viewer with a precision better that 1 mm.



Thank you for your attention …

david martin high precision beamline alignment at the esrf ...david martin . high precision beamline...

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