MAX IV 3 GeV Ring Commissioning

APS-U Risk Management Workshop Feb 2016

MAX IV 3 GeV Ring Commissioning

Pedro F. Tavares on behalf of the MAX IV team

APS-U Risk Workshop / Feb 2016


Summary

●The MAX IV Facility

●The MAX IV 3 GeV Ring

● Project Timeline

●Technical Challenges

●Commissioning Highlights

●Risk Management in the MAX IV Project

●Conclusions – Next Steps


Conceptual Basis of the MAX IV Design

• Scientific Case calls for high brightness radiation

over a wide spectral and time range: IR to Hard R-

rays, Short X-Ray Pulses.

• Need for high brightness: low emittance and

optimized insertion devices.

• This is hard to achieve in a single machine:

• higher electron beam energy harder photons

• lower electron beam energy softer photons

One size does not fit all !


The MAX IV Approach

●Different machines for different uses: • A high energy ring with ultra-low emittance for

hard X-ray users.

• A low emittance low energy ring for soft radiation users

• A LINAC based source for generating short pulses and allowing for future development of an FEL source.


MAX IV - An integrated Solution

MBA Lattice Ultra-low emittance robust, high stability. large momentum aperture

Large

Number

of

Magnets

Small

Magnet

Apertures

Wake-Fields

Low RF frequency

Full Energy

Injector LINAC:

Short Pulses

Long

Bunches

Landau

Cavities

Compact

Magnet Design.

High precision,

High vibration

frequencies

Narrow

vacuum

Chambers

Multi-

purpose

Strong

Magnets

IBS

Low Vacuum

Conductance High Heat

Load

Density

Copper

Chambers

100 %

NEG

Coating


© Photo: Perry Nordeng 18-Sept-2014

Energy 3 GeV

Current 500 mA

Emittance 0.2 - 0.33 nm rad

Circumference 528 mA

# straight sections 20 5 m

APS-U Risk Management Workshop Feb 2016 Annika Nyberg, MAX IV-laboratoriet, 2012

MAX IV – an overview

Linear Accelerator

3 GeV Storage Ring

1.5 GeV SR

Short Pulse Facility


The MAX IV 3 GeV ring Lattice 7-bend achromat 20 periods

Picture MAX IV DDR

Matching Cells

Unit Cells

APS-U Risk Management Workshop Feb 2016 Slide by Martin Johansson

MAX IV 3 GeV Ring DC Magnets • Each cell is realized as one mechanical unit containing all magnet elements. •Each unit consists of a bottom and a top yoke half, machined out of one solid iron block, 2.3-3.4 m long.


DC Magnet Production History 100

80

60

40

20

0

% D

eliv

ere

d

Feb

/20

14

Ma

r/2

01

4

Ap

r/2

01

4

Ma

y/2

01

4

Jun

/201

4

Ju

l/2

01

4

Au

g/2

01

4

Se

p/2

01

4

Oct/

20

14

94 % delivered100 % approved for delivery

All Blocks M1, M2, U3 U1, U2, U4, U5


One achromat

MAX IV 3 GeV ring vacuum system layout

BPM

Ion pump location

Absorber location

Sector valve location

VC10 VC1

VC2 VC3

VC4

VC5

VC6

VC7

VC8

VC9

Slide by E.Al-dmour


Chamber Production History

100

80

60

40

20

0

% C

om

ple

te

Jul/2013 Oct/2013 Jan/2014 Apr/2014 Jul/2014 Oct/2014

Parts ready Assembled Cleaned Tested

“standard “ chambers


First Assembly Results from MAX IV – Mockup tests

Pictures by Chiara Pasquino


3 GeV Ring Commissioning Timeline

Beam in TR3

Aug 11

2015

First Turn

Aug 25

2015

Stored Beam

0.1 mA

Sep 15

2015

Stacking

4 mA

Oct 08

2015

First Light

Nov 2

2015

120 mA

Jan/31

2016


Early Commissioning Results

● Beam observed at the end of TR3 and into the ring.

M1

2015/08/11

Picture J.Alhbäck


Threading the beam – first turn – many turns

2015/08/26 2015/08/27

3 passes

35 passes

2015/08/25

All correctors OFF


First Stored Beam

Injected beam

Injection Stored beam 2 seconds after previous injection pulse

Kicker Current

Revolution period

2015/09/15


Capture and Bunching

2015/09/23

First pass

500 MHz from Chopper 100 turns 150 turns

175 turns 200 turns

Plots S.Leeman


Linear Optics Characterization: Integer Tunes

-2

-1

0

1

2

DX

[m

m]

500400300200100

S[m]

Model Experiment

M1-COAX-01 changed by 0.1 mrad

-1.0

-0.5

0.0

0.5

1.0

DY

[mm

]

500400300200100

S[m]

Model Experiment

M1-COAY-01 changed by 0.1 mrad


LOCO: reduction in dispersion beating Before LOCO

After LOCO


Linear Optics Characterization: Fractional Tunes

Horizontal Tune from TBT data Excitation by Kicker&Pinger

qy=0.22 qx=0.32

Tunes on Spectrum Analyzer Excitation by Stripline


Chromaticities:


BPM Offsets ● Measured by BBC using trim coils in sextupole magnets

-1.0

-0.5

0.0

0.5

1.0

Off

se

t [m

m]

500400300200100

S[m]

Horizontal Vertical

RMS: 144 µm H / 138 µm V


Orbit Correction Residual RMS: 0.7 µm H / 62 µm V

-2x10-3

-1

0

1

2

X[m

m]

500400300200100

S[m]

Horizontal OrbitRMS = 0.7 µm

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

Y[m

m]

500400300200100

S[m]

Vertical OrbitRMS = 62 µm


Injection Efficiency - 1


Injection Efficiency - 2


Vacuum Conditioning - pressure

Plot by E.Al-dmour


Beam Lifetime 1600

1400

1200

1000

800

600

400

200

0

I*[

mA

.hr]

12:00 AM1/31/2016

2:00 AM 4:00 AM 6:00 AM

0.10

0.08

0.06

0.04

0.02

0.00

Curre

nt[A

]

ITAU Current

300

250

200

150

100

50

0

Am

pC

avLoops[m

V]

12:00 PM1/30/2016

3:00 PM 6:00 PM

1600

1400

1200

1000

800

600

I*[mA

.hr]

r3-a101911cab03/rf/nutaq-01/diag_ampcavloopsa_value ITAU

400

300

200

100

0

r3-a

10

01

11

ca

b0

3/r

f/n

uta

qd

iag

s-0

1/d

iag

_a

mp

lan

da

ub

[m

V]

3:00 AM1/31/2016

6:00 AM 9:00 AM 12:00 PM

1600

1500

1400

1300

1200

1100

1000

I*[mA

.hr]

r3-a101911cab03/rf/nutaqdiags-01/diag_amplandaua_value ITAU


Collective Effects – Single Bunch ● No signs of TMCI up to 8.55 mA (nominal 2.8 mA/bunch).

● Significant bunch lengthening even without harmonic cavities

-2.0

-1.5

-1.0

-0.5

0.0

Q

y/Q

s

6543210

Single Bunch Current [mA]

180

160

140

120

Bunch L

ength

FW

HM

(ps)

2.52.01.51.00.5

Single-Bunch Current [mA]


Collective Effects - Multibunch

● Possible to store >120 mA without feedback and without harmonic cavities. Predicted RW threshold was only ~ 40 mA !

● HOM driven longitudinal motion is evident at a few mA in uniform fill.

● Temperature tuning has proved effective in fighting longitudinal CBI.

● Harmonic Cavities not fully tuned-in in yet. Need more conditioning

● Preliminary BBB feedback tests using a short stripline showed a longitudinally stable beam up to 35 mA.

● Longer striplines for BBB feedback to be installed in february

● Longitudinal Actuator (cavity) under design


Sigma polarized SR, 632.8 nm, SRW calculation (left) and measured image (right). The simulation is done for εx = 320 pm rad, βy = 1.5 m. Both figures show a 2 x 2 mm^2 area of the image plane. The fringe pattern is too weak to be visible. Optical magnification of m=-2.28 is taken into account in the SRW model Horizontal opening angle: 6 mrad Vertical opening angle: 8 mrad Exposure time: 2.9 ms

Slide by J.Breulin

Emittance Measurement


Horizontal intensity profile of imaged sigma polarized SR. Due to the reduced horizontal opening angle the fringe pattern is not as pronounced as it could be, but easier to understand and to calculate. Present setup is limited by optical aberations (from misalignments) and surface quality from optical components (some are inherited from MAX II, MAX III). Steady improvements during the next weeks are planned. Camera linearity might also be an issue! Challenges on the SRW model side are to include for example: variation of dipole field, variation of beta_x, variation of vertical opening angle, along the observed electron beam path.

Slide by J.Breulin


Main Problems/Difficulties

● RF Cavity Conditioning

● RF System commissioning (LLRF, Shunt Groups)

● Diagnostic System Commissioning

– BPMs

● Kicker Magnet PS failure

● Gun Klystron Failures

● Long Radiation Surveys

● Cooling System Failures

● Control System Commissioning

● PS Failures


Next Steps ● February 2016: First two in-vacuum undulators, Striplines for BBB

feeback.

● March to July 2016: – Further conditioning of RF cavities

• Main cavities • Harmonic cavities

– Further linear optics trimming • LOCO, shunting

– Non-linear optics trimming – Collective Effects studies (Harmonic cavity tuning) – Bunch-by-Bunch feedback commissioning

● May 2016: 2 EPUs in the 3 GeV Ring, Transfer Line and LASt Achromat in 1.5 GeV ring

● September-December 2016 : 1.5 GeV ring commissioning

● November 2016: Friendly users (3 GeV ring)

● March 2017: First open call users (3 GeV ring)

● Feb 2017: First Ids in the 1.5 GeV ring

● May-June 2017: LINAC RF upgrade


Risk Management for the MAX IV Project

Risks Probability Impact Mitigating Measure

Delays due to procurement

procedures High High

Detailed procurement planning with

participation from technical

personnel. Reinforce procurement

team.

Errors in Planning and/or

need to direct manpower to

other activities Medium High

Close follow-up of milestones;

Unambiguous declaration of

priorities by upper management.

Exchange rate Fluctuations Low High

Follow market trends; Financial

management

Dependence on few

suppliers for long lead items Medium High

Make the design such that more

competition from different suppliers

is possible

Loss of Key personnel Low High Maintain team motivation

General Risks

Early risk identification exercise (Autumn 2010)


Eaarly Risk Identification Exercise (cont.)

Delays in Conventional

Facilites Project Medium High Close follow-up of milestones

Changes to Requirements

on Conventional Facilities Medium High Active integration management

Delays in Long Lead Items -

Magnets, Vacuum Low High Close follow-up of milestones

Difficulties in reaching

magnet machining

tolerances High High Early prototyping

Delays in Long Lead Items -

RF Cavities - operation at

high power. Medium High

Close follow-up of milestones;

Close interaction in development

with supplier

Vibration and Support

Design Medium High Early Testing and Prototyping

Delays in installation due to

cabling Medium Medium

Detailed planning; Early set up

adequate integration tools; design

for simple installation

Neg coating - single supplier Medium High

Early technical discussions and

early procurement.

Technical/Development Risks

Risks Probability Impact Mitigating Measure


Risks/Challenges that became apparent later

● Transition from Prototype to series production

● Integration

● Control System readiness for commissioning

● RF Transmitters


Conclusions

● Progress with the initial phase of MAX IV 3 GeV ring commissioning gives us increased confidence that the MBA concept is sound.

● Much is still to be done to reach the final design specifications, but nothing indicates there is any fundamental obstacle ahead.

● Most difficulties are related to technical subystems that need time for conditioning/maturing

Documents

MAX IV 3 GeV Ring Commissioning