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BIW `06, May 1st 2006
Beam Diagnostics Challenges in the FAIR project at GSI
Beam Diagnostics Challenges in the FAIR project at GSI
The FAIR project - a Facility for Antiproton and Ion Research
Planning of FAIR beam diagnostics done by Peter Forck and Andreas Peters togetherwith the GSI BD group and collaborators
Beam Diagnostic Challenges in the FAIR Project 2Andreas Peters, Peter Forck
BIW `06, May 1st 2006
OutlineOutline
The FAIR project – a short introduction to the accelerator
parameters and the facility layout and operation modes as well
as the research aims
Challenges in the accelerator parameters
Linked general challenges for the beam diagnostic equipment
(diversity and dynamics)
Examples of beam diagnostic challenges in detail and R&D for
possible solutions:
Current measurement in SIS100 from dc to short single bunch
operation
BPM systems for the cryogenic synchrotrons with varying
acceleration frequencies
Turn-by-turn profile measurement (RGM) in synchrotrons and
storage rings with high repetition rates (MHz) under UHV
conditions
Summary and outlook
Beam Diagnostic Challenges in the FAIR Project 3Andreas Peters, Peter Forck
BIW `06, May 1st 2006
FAIR – Basic Layout and Parameters (1)FAIR – Basic Layout and Parameters (1)
Beams now:Z = 1 – 92(protons to uranium)up to 2 GeV/nucleonSome beam cooling
Beams now:Z = 1 – 92(protons to uranium)up to 2 GeV/nucleonSome beam cooling 100 m
TodayToday Future ProjectFuture Project
Beams in the future:Intensity: 100 – 1000 fold Species: Z = -1 – 92(anti-protons to uranium) Energies: up to 35 - 45 GeV/uPrecision: full beam cooling
Beams in the future:Intensity: 100 – 1000 fold Species: Z = -1 – 92(anti-protons to uranium) Energies: up to 35 - 45 GeV/uPrecision: full beam cooling
Beam Diagnostic Challenges in the FAIR Project 4Andreas Peters, Peter Forck
BIW `06, May 1st 2006
FAIR – Basic Layout and Parameters (2)FAIR – Basic Layout and Parameters (2)
Final facility layout with all planned buildings
Tunnel for SIS100/300 at a depth of about 17m to comply with the requirements of radiation safety
Beam Diagnostic Challenges in the FAIR Project 5Andreas Peters, Peter Forck
BIW `06, May 1st 2006
FAIR – Basic Layout and Parameters (3)FAIR – Basic Layout and Parameters (3)
Injector chainInjector chain
100 m
Main synchrotrons of FAIR:SIS100, 2T, pulsed sc. magnets,29 GeV, 4·1013 protons, 25 ns2.7 GeV/u, 1012 U28+-ions, 60 nsSIS300, 6T, pulsed sc. magnets,34 GeV/u, 4·1011 U92+-ions,slow extraction (1 – 100 s)
Main synchrotrons of FAIR:SIS100, 2T, pulsed sc. magnets,29 GeV, 4·1013 protons, 25 ns2.7 GeV/u, 1012 U28+-ions, 60 nsSIS300, 6T, pulsed sc. magnets,34 GeV/u, 4·1011 U92+-ions,slow extraction (1 – 100 s)
Booster synchrotron SIS18:2.7·1011 U28+-ions, 2.7 Hz5.4·1012 protons, 4 Hz
Booster synchrotron SIS18:2.7·1011 U28+-ions, 2.7 Hz5.4·1012 protons, 4 Hz
UNILAC (upgraded):15 emA U28+, 11.4 Mev/u
UNILAC (upgraded):15 emA U28+, 11.4 Mev/u
p-Linac (new):70 mA, 70 MeV
p-Linac (new):70 mA, 70 MeV
Beam Diagnostic Challenges in the FAIR Project 6Andreas Peters, Peter Forck
BIW `06, May 1st 2006
FAIR – Basic Layout and Parameters (4)FAIR – Basic Layout and Parameters (4)
100 m
HESR: stoch. cooling up to14 GeV antiprotons, e-coolingup to 9 GeV, internal target
HESR: stoch. cooling up to14 GeV antiprotons, e-coolingup to 9 GeV, internal target
Targets and storage rings of FAIR:Targets and storage rings of FAIR:
SFRS TargetSFRS Target
CR: stochastic cooling of RIBs,and antiprotons, mass spectr.RESR: accumulation of anti-protons, fast decel. of RIBsNESR: e-cooling of RIBs andand antiprotons, precise massspectr., e-n scattering facility
CR: stochastic cooling of RIBs,and antiprotons, mass spectr.RESR: accumulation of anti-protons, fast decel. of RIBsNESR: e-cooling of RIBs andand antiprotons, precise massspectr., e-n scattering facility
Antiproton TargetAntiproton Target
Beam Diagnostic Challenges in the FAIR Project 7Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Scheme of FAIR Parallel OperationScheme of FAIR Parallel Operation
Beam Diagnostic Challenges in the FAIR Project 8Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Research Areas at FAIRResearch Areas at FAIR
100 m
Hadron Physicswith antiprotons
Nuclear Structure & Astrophysicswith radioactive beams
Plasma Physicswith compressedion beams & high-intensity petawatt-laser High EM Field (HI) ---
Fundamental Studies (HI & p)Applications (HI)
Nuclear Matter Physics with35-45 GeV/u HI beams
Beam Diagnostic Challenges in the FAIR Project 9Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Challenges in the Accelerator Parameters (1)
Challenges in the Accelerator Parameters (1)
Fast cycling superconducting magnets: For SIS 100 superconducting magnets (2 T)
with 4 T/s ramping rate are required. SIS 300 will be equipped with 6 T (1 T/s)
dipole magnets. The optimization of the magnet field quality for low loss, high
current operation with beams filling large parts of the acceptance is of great
importance.
Control of the dynamic vacuum pressure caused by beam loss induced desorption
of heavy molecules, which can cause the rapid increase of the residual gas
pressure a novel collimation concept is presently under test at the SIS18.
Cooled secondary beams: Fast electron and stochastic cooling at medium and at
high energies will be essential for experiments with exotic ions and with
antiprotons.
High RF voltage gradients: The fast acceleration and bunch compression of intense
heavy-ion beams down to ~60 nanosecond bunch length (protons: ~25 ns)
requires compact RF systems. Complex RF manipulations with minimum phase
space dilution and the reduction of the total beam loading in the RF systems are
important R&D issues.
Operation with high brightness, high current beams: The synchrotrons will operate
close to the space charge limits with tolerable beam losses of the order of a few
percent. The control of collective instabilities and the reduction of the ring
impedances is a subject for the R&D phase.
Beam Diagnostic Challenges in the FAIR Project 10Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Challenges in the Accelerator Parameters (2)
Challenges in the Accelerator Parameters (2)
Straight section of the synchrotron tunnel with a shielded small recess building
Cross section of the synchrotron tunnel with an inner size of 5 x 4 m2, SIS100 (bottom) and SIS300 (top) cryostats are shown with cryogenic bypass lines (yellow)
Beam Diagnostic Challenges in the FAIR Project 11Andreas Peters, Peter Forck
BIW `06, May 1st 2006
General Challenges for Beam Diagnostics (1)
General Challenges for Beam Diagnostics (1)
Despite quite different beam parameters of the FAIR synchrotrons and
storage rings, common realizations of SIS100, SIS300 and all storage ring
diagnostics are mandatory to save man-power and costs during the R&D
phase and enable a cost reduction due to the large quantities during the
construction phase.
Large dynamic range, e.g. in SIS100: from low currents beams for
adjustments up to space charge limited intensities of heavy ions, from
long bunches at injections up to short pulses after bunch rotation /
compression.
Because the acceptance was limited to 3*emittance (KV-Distribution) in
the synchrotrons and 2*emittance in the transfer lines , a precise
alignment of the beam in the vacuum pipe is strongly advised. The beam
diagnostics system has to allow a precise orbit measurement and the
capability for online feedback on the closed orbit, on the betatron tune,
on chromaticity and on coupling.
If the loss budget in the superconducting synchrotrons is only a few
percent, current measurements with high accuracy (~10-4) for controlling
beam losses are mandatory.
Beam Diagnostic Challenges in the FAIR Project 12Andreas Peters, Peter Forck
BIW `06, May 1st 2006
General Challenges for Beam Diagnostics (2)
General Challenges for Beam Diagnostics (2)
Due to the compactness of all accelerators the repetition rates are quite
high (up to the MHz region), which is a challenging task e.g. for turn-by-
turn profile measurements based on a RGM system.
Additional constraints have to be fulfilled, which are sometimes
challenging:
installations in cryogenic parts of the accelerators,
UHV conditions (pressure: 5×10-12 mbar) and
high radiation levels.
The complex, „quasi-parallel“ operation scheme demands a highly
reliable and flexible data acquisition system adapted to the fast pulsed
machines parameters.
Complicated scheme of transport lines with high diversity of magnetic
rigidities.
Beam Diagnostic Challenges in the FAIR Project 13Andreas Peters, Peter Forck
BIW `06, May 1st 2006
General Challenges for Beam Diagnostics (3)
General Challenges for Beam Diagnostics (3)
not part of thebeam lines
sc 100 Tmsc 90 Tm
18 Tm13 Tm
sc 300 Tm
SIS18
SIS300
Dump
CBMPP2
AP
CR
RESR
SFRSTarg
LE-Cave
HE-Cave
NESR
FLAIR
HESR
PP1 PbarTarg
SIS100
1
2 34
5 67
8
910
11
12 1314 15
16
17 18 1921
22 23
24
2526
27
28
29
20
30
31
32
3334
35
36
37
3839
40
4142
43 4445
46
D
A
BC
E F
G H I
J K LMN
O
P Q
R
ST
U
Schematic view of FAIR beam transport lines
Total length of about 2350 m of allbeam lines (excluding Antiproton-
Separator, FLAIR beam lines, ...), divided in 46 sections with differing parameters.
In the transfer lines the high dynamic range of intensities and energies as well as ion species leads to the necessity of destructive measurement methods needed for low currents and in parallel to non-destructive devices for high currents which would destroy any material in the beam optical path.
Beam Diagnostic Challenges in the FAIR Project 14Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Beam Diagnostic Challenges in DetailBeam Diagnostic Challenges in Detail
Examples of beam diagnostic challenges concerning the ring
accelerators in detail and R&D for possible solutions:
(1) Current measurement in SIS100 from dc to short single bunch
operation (operating bandwidth of 10 kHz)
(2) BPM systems for the cryogenic synchrotron environment with
varying acceleration frequencies
(3) Turn-by-turn profile measurement (RGM) in synchrotrons and
storage rings with high repetition rates (MHz) under UHV
conditions
Beam Diagnostic Challenges in the FAIR Project 15Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (a)Current Measurement in SIS100 (a)
Injection (4*stacking)
Protons U28+
Nmax 4*1013 5*1011
E [MeV/u] / trev [µs] 2000 / 3.81 92 / 8.72
Icoasting/Ibunch [A] 1.6 / 8 0.28 / 1.45
After acceleration
E [GeV/u] / trev [µs] 26 / 3.62 2.38 / 3.76
Icoasting/Ibunch [A] 1.8 / 8.8 0.6 / 3.2
After bunch merging & compression (h: 8 1, bunch length 25/60 ns)
Icoasting/Ibunch [A] 1.8 / 384 1.2 / 57
Theoretical upper limits of currents in SIS100
Beam Diagnostic Challenges in the FAIR Project 16Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (b)Current Measurement in SIS100 (b)
Solutions: a) Use the NPCT of Bergoz; an installation in SIS18 is scheduled for August 2006 and tests starting in October 2006 – Question: Will the feedback loop of the NPCT work stable under high current bunched beam condition (bunch frequency of some MHz) ?
Severe problem of GSI DCCT: Above specific levels of beam current and/or revolution frequency the loop starts to oscillate (right). Mostly it gets back control. But: Did it settle to the correct working point ?
Beam Diagnostic Challenges in the FAIR Project 17Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (c)Current Measurement in SIS100 (c)
Solutions: b) Design of an alternative current measurement based on the idea of a clip-on ampere-meter with a GMR sensor in the gap of a toroidal core (collaboration with University of Kassel, Germany).
Simulated magnetic flux in a slit toroidal coreScheme of an clip-on ampere-meter
Beam Diagnostic Challenges in the FAIR Project 18Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (d)Current Measurement in SIS100 (d)
Assuming a measurement bandwidth of 10 kHz, the resolution of different GMR sensors is in the order of ~100 nT
Resolution measurement of different GMR sensors (by NVE corporation)
Beam Diagnostic Challenges in the FAIR Project 19Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (e)Current Measurement in SIS100 (e)
Data sheet characteristics:
Saturation field: 10 mT
Specified linear range:± 0 – 7 mT
Operating frequency: dc 1 MHz
Example for the DC characteristics of a GMR sensor (NVE AA005)
Measurements concerning high frequency behaviour are under way !
Beam Diagnostic Challenges in the FAIR Project 20Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Current Measurement in SIS100 (f)Current Measurement in SIS100 (f)
Construction of a first test set-up with a split core (either VITROVAC 6025 F or CMD 5005 from CMI ferrite) and two gaps for sensor positioning to be built in
SIS18 in autumn 2006
Due to the two half shells an installation without vacuum break is possible!
Existing SIS18 DCCT with added new core
Details
Beam Diagnostic Challenges in the FAIR Project 21Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development - detector (a)BPM development - detector (a)
Curved section of SIS100
Straight section of SIS100
Beam Diagnostic Challenges in the FAIR Project 22Andreas Peters, Peter Forck
BIW `06, May 1st 2006
Apertures/mm:
horizontal = 268
vertical = 116
length = 350
separation rings on the ground potential
simulated beam
BPM development – detector (b)BPM development – detector (b)
Different types of BPMs are necessary:
• SIS100 version: elliptical, cryogenic
• SIS300 version: round, cryogenic
• Storage rings: large aperture up to 300 mm, normal temperature env., but high bakeout temperaturesPosition sensitivity and linearity:
For shoe-box type calculated
Δx(f) = K(f) * Δ/Σ+ offset(f)
Careful mechanical design
(high f by bunch-compression)
R&D: Matching RF- and cyrogenic requirements
Starting point: ESR BPM
Necessity of guard rings (1)
Beam Diagnostic Challenges in the FAIR Project 23Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development – detector (c)BPM development – detector (c)
Necessity of guard rings (2)
Cross talk between plates in one plane (should be low!)
Simulations on ESR type:Geometry Structure on ceramics
Metal plates
no guard ring 1mm gap
-5.1dB -7.9dB
no guard ring 2mm gap
-8.1dB -10.8dB
with guard ring -20.8dB -22.5dB
separation rings on the ground potential
Metal plates seem to be the better choice, but:
Mechanical stability of an arrangement of numerous single metal plates is poor due to experience from collaborators in Dubna (Nuclotron)!
Structure on ceramics chosen!
Beam Diagnostic Challenges in the FAIR Project 24Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development – detector (d)BPM development – detector (d)
Present layout of SIS100 BPM version
(elliptical shape)
BPM parameters:
Capacity: ~ 100 pF
Length: 30 cm
For maximal beam current i.e. Nz 4x1013 e/bunch and bunch length of 25 ns:
Qm=4.3 x 10-7 C
U=4.3 kV
For minimal beam current i.e. Nz 4x108 e/bunch and bunch length of 60 ns:
Qm=4.4 x 10-13 C
U=4.4 mV
Barrier bucket behaviour (long bunches!) not studied until now!
Further adjustment of parameters needed!
Beam Diagnostic Challenges in the FAIR Project 25Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development – analog electronics (e)BPM development – analog electronics (e)
In the case of SIS100/300 the hybrid must most likely positioned in the cryogenic area!
From CS
J. Belleman
(from CERN-PS)
Beam Diagnostic Challenges in the FAIR Project 26Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM – data acquisition and analysis (f)BPM – data acquisition and analysis (f)
Behind the amplifier chain no additional analog signal treating direct digitization!
Common EU-FP6-initiative of GSI, CERN and Instrumentation Technologies for a digital data evaluation platform for fast cycling hadron machines with varying frequencies:
Main board 4 channel ADC input board
Scheme of Libera electronics
Beam Diagnostic Challenges in the FAIR Project 27Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development – data acquisition and analysis (g)
BPM development – data acquisition and analysis (g)
Two different approaches for data evaluation are under development now:
CERN: digital version of classical base line restoring and PLL implementation using RF frequency input and phase tables
GSI: Free running algorithm with the following implementation:
PU signal
Libera
ADC Averaging for noise reduction, using a median filter with a short length of 5
taps
Summing of each data sample at the input -> gate
construction using the fact that the data between 2 bunches should have a linear trend
FPGA
Integration over each
bunch using the
constructed gates
SBC
Position calculation outside the
FPGA due to floating point
limitation
Beam Diagnostic Challenges in the FAIR Project 28Andreas Peters, Peter Forck
BIW `06, May 1st 2006
BPM development – data acquisition and analysis (h)
BPM development – data acquisition and analysis (h)
Results of offline implementation/calculation:
Both methods (CERN/GSI) are under development and implementation in FPGA code; test are foreseen in the 2nd half of 2006 !
Measurement in SIS18 harmonic number = 4
Beam Diagnostic Challenges in the FAIR Project 29Andreas Peters, Peter Forck
BIW `06, May 1st 2006
RGM Development – Requirements (a)RGM Development – Requirements (a)
Parameters given by the machines:• Revolution frequency
• in SIS 100/300: 110 – 280 kHz• in the Storage Rings: 125 kHz – 1.4 MHz
• Beam pipe apertures:• in SIS 100/300: 135 * 65 mm2, resp. 90 mm in diameter (SIS300)• in the Storage Rings: up to 300 mm in diameter• adaptive spatial resolution down to 0.1 mm (rel. 1%) necessary due to cooled beams• Transversal measurement range: ~ 100 mm
• Turn-by-turn readout necessary e.g. for matching of the injected beam emittance orientation and dispersion setting with respect to the acceptance• Detection of secondary e-/ions ( conversion with e.g. phosphor P47) , thus
• E-field (E50 V/mm, 1% in-homogeneity) and• B-field for guidance (B0.03 T, 1% in-homogeneity) compact because of limited space
• Read-Out Modes: a) high resolution measurement on ms time scale with CCD camera
b) turn-by-turn: array of ~100 photo-diodes or multi-anode PM or SiPM
Beam Diagnostic Challenges in the FAIR Project 30Andreas Peters, Peter Forck
BIW `06, May 1st 2006
RGM development – mechanical design (b)RGM development – mechanical design (b)
First design of RGM with magnets, but the following changes are necessary:
• Possibility of change between CCD and multi-diode readout
• Due to low magnetic rigidities in the storage rings compensations of the applied magnetic fields of the RGM are necessary more complex magnet installations
• Alternative design with permanent magnets is under calculation at ITEP, Moscow
First test of RGM version with CCD readout, but without magnetic field are foreseen in collaboration with FZ Jülich at their COSY proton storage ring in the 2nd half of 2006!
Beam Diagnostic Challenges in the FAIR Project 31Andreas Peters, Peter Forck
BIW `06, May 1st 2006
RGM development – turn-by-turn readout (c)RGM development – turn-by-turn readout (c)
Alternative sensor for turn-by-turn readout: Silicon Photomultiplier (B. DOLGOSHEIN et al., MEPI, Moscow)
First commercial sensor on the market (www.SensL.com)
Up to 103 silicon micro pixels per mm2, dimensions scalable
Beam Diagnostic Challenges in the FAIR Project 32Andreas Peters, Peter Forck
BIW `06, May 1st 2006
The Most Challenging Part of the FAIR Project ...
The Most Challenging Part of the FAIR Project ...
Realisation/Stage Plan
2007 (start of final design) 2014
Stage 1 Stage 2 Stage 3
Beam Diagnostic Challenges in the FAIR Project 33Andreas Peters, Peter Forck
BIW `06, May 1st 2006
AcknowledgementAcknowledgement
Instead of a summary:
Thanks to all colleagues and collaborators contributing to
this talk with their papers and pictures!
Thanks to our small technical review board (Tom Shea and
Hermann Schmickler) for valuable discussion and their
consulting!
Thanks for your attention!
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