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• Status of the accelerator
• Upgrade plans - PETRA IV
PETRA III - status and upgrade plans.
Rainer WanzenbergDESY - MPE -
SLAC visitOct 10 - 13, 2016
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 2
PETRA - History
The PETRA ring was built in 1976 as an electron – positron colliderand was operated from 1978 to 1986 in this collider mode.
From 1988 to 2007 PETRA II was used as a pre-acceleratorfor the HERA lepton hadron collider ring.
ZeusH1
Hermes
Hera-B
p 40 GeV
e+- 12 GeV
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 3
PETRA as an e+ / e- collider
ConferenceBergen, June 1979:
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 4
PETRA II: 1988 - 2007
e+ or e-: 12 GeVp : 40 GeV
Linac IIPIADESY II
DORIS was operatedas a synchrotron lightsource until 2012(C = 289 m, E = 4.5 GeVεεεεx = 410 nm)
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 5
PETRA III – Construction of the Experimentall Hall
2007 – 2008: The PETRA ring has been converted into a synchrotron light facility.
One octant of the PETRA tunnel has been removed(photo Aug. 2007).
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 6
PETRA III in 2009
Hall NE
Hall E
Max von Laue Hall
Parameter PETRA III
Energy / GeV 6
Circumference /m 2304
Total current / mA 100
Emittance (horz. / vert.) /nm 1 / 0.01
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 7
PETRA III in 2014: Extension Project, two new halls
Implementation of the PETRA III extension: Feb 2014 – Feb 2015
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 8
The DESY site in 2016
Ada Yonath Hall (Extension Hall East) Naming ceremony Sep 14, 2016
Paul P. Ewald Hall (Extension Hall North)Max von Laue Hall
LINAC II PIA DESY II PETRA IIIC = 29 m, E =450 MeV C = 293 m, E = 6 GeV C = 2304 m, E = 6 GeV
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 9
PETRA III
Parameter PETRA IIIEnergy / GeV 6Circumference /m 2304Emittance (horz. / vert.) /nm 1.2 / 0.012Total current / mA 100Number of bunches 960 40Bunch population / 1010 0.5 12Bunch separation / ns 8 192
Damping Wigglers: B ~ 1.5 T, λλλλ = 0.2 m2 x 10 x 4 m = 80 mεεεεx: 5 nm 1.2 nm
Dispersion correction in the wiggler sections:Dx < 18 mm, D y < 5 mm
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 10
Dispersion correction
Wiggler
G.K. Sahoo et al., IPAC.10, THPD086
Horz. plane:combined orbit (u) + dispersion correction D u
R orbit response matrix,S dispersion response matrix
Vert. Dispersion:12 skew quads
horz. offset x = D x∆∆∆∆p/pgenerates vert. kick, whichcan be used to minimize thevert. dispersion
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 11
PETRA III – components
Wigglers
FODO Arc
RF Injection
Longt. Feedback
Undulators
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 12
Hybrid Lattice: DBA and FODO
Qx = 37.12, Qy = 30.27, Energy loss per turn: 5.1 MeV (1.3 MeV without wigglers)
FODO Arc: 14 cells (14.4 m)28 dipoles (28 mrad)L = 5.35 m
DBA octant: 8 cells (23 m)18 dipoles (43.3 mrad) + 5 canting dipoles ( 5 mrad)
L = 1 m L = 0.3 m
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 13
Lattice (cont.)
Extension, DBA like cells DBA octant: canted cell
DipolesL = 1 m
L = 0.5 m(canting)20 mrad
PDA 37 mrad
PDE 20 mrad
PDA 27 mrad
PDD 27 mrad
PDE 20 mrad
PDA 37 mradB = 0.8 … 1 TI ~ 450 A
5 mradPDC
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 14
Beamlines: Max von Laue Hall
Number ID Type Energy range (keV) Cell
P01 10 m U32 (2 x 5 m) 5 – 40
P02 2 m U23 20 – 100 1
P03 2 m U29 8 – 25 1
P04 4 m U65 (APPLE) 0.2 – 3.0 2
P05 2 m U29 8 – 50 3
P06 2 m U32 2.4 – 50 3
P07 (option
low beta)
4 m U19 (IV)
(pres. 2m)
50 – 300 4
P08 2 m U29 5.4 – 30 5
P09 2 m U32 2.4 – 50 5
P10 5 m U29 4 – 25 6
P11 2 m U32 8 – 35 7
P12 2 m U29 4 - 20 7
P13 2 m U29 5 – 35 8
P14 2 m U29 5 - 35 8
High βx
Low βx
High beta: ββββx = 20 m ββββy = 4 mLow beta : ββββx = 1.4 m ββββy = 4 m
Max von Laue Hall: 14 beam lines8 DBA cells ( length 23 m)
Apple PU 4
Undulator PU 10
Undulators PU 8 & PU 9
Beam size:~ 150 µµµµm x 6 µµµµm(high beta)
Orbitstability requirement:
submicron~ 0.6 µµµµm (vert.)
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 15
Fast Orbit Feedback
Digital system:Main Processing Unit
244 BPMs (Libera Electronics)
50 Fast Correctors (vert. + horz.)driven by Digital Power Amplifiers (DPA) (DC to 1 kHz, max. 20 A)
J. Klute, H.-Th. Duhme et al., DIPAC’11, MOPD76
Slow correctors:184 (+ 26) horz. + 194 vert.
Slow corrector
Fast corrector
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 16
Orbit stability – Quality factor
Position Quality= 100 % x
margin: 5 µµµµm (vert.)15 µµµµm (horz.)
90 % 0.5 µµµµm offset from ideal position (vert.)
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 17
New beam lines: Tentative time line
First beam
P65 X-ray absorption spectroscopy Oct. 2015
P64 X-ray absorption spectroscopy Spring 2016
P24 Chemical crystallography 2Q 2017
P21 High-energy X-ray materials science 2Q 2017
P22 Nano X-ray spectroscopy 2Q 2017
P23 Nano X-ray diffraction 2Q 2017
P66 Time-resolved luminescence spectroscopy t.b.d.
P61 High-energy X-ray eng. mat. sci. (HZG) LVP extreme conditions (DESY) 2018
P62 Small-angle X-ray scattering >2018
P63 t.b.c. -----P25 t.b.c -----
Phase 1P
hase 2P
hase 3
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 18
PETRA III Extension North
New Beam lines P64 and P65
Tue 8.9.15, first photon beams from PU64and PU65, 1 mA run
P 65 First experiments in Oct. 2015 scheduled user from June 2016
P 64 First experiments in May 2016
after a problem with the monochromater was solved
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 19
Satellite bunches
Timing mode with 40 Bunches, some experiments need a very good bunch purity (~ 10-9 … 10-8 )But there are satellite bunches generated in PETRA (2 ns and 4 ns) from the injector chain (125 MHz in PIA)
Measurement at beam line P01, July 31, 2015 13:45 h
Studies started Aug. 2015: satellite bunch clearingusing the Multibunchfeed back system
Ref.:Longt. bunch structure in the Photon FactoryT. Obina et al. NIM A 354 (1995) 204-214
Bunch Purity Measurements at PETRA IIIJ. Keil et al. IPAC 2016
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 20
Multi bunch feedback
||effrf
B
||
effxtot
0
21
/41
ZV
I
ZeE
I
sΩ=
= ⊥⊥
τ
πβ
ωτ
Required damping 1/ ττττ:Longt. 800 Hz or 1.25 msHorz. 1400 Hz;Vert. 1400 Hz or 0.7 msBandwidth 62.5 MHz(8 ns bunch spacing)
Sattelite bunch clearing:
longitudinal horizontal vertical
Ithres (mA) 7 6 6
1/ττττ (Hz) 35 50 60
Zeff 3.6 MΩ 45 MΩ/m 54 MΩ/m
Coupled bunch instabilities in PETRA:
→ powerful broadband feedback neccessary
PETRA III: 12 seven cell cavities which large par. shunt impedance
J. Klute, K. Balewski et al., DIPAC’11, TUPD81
Intensity dependent tune shift:
~ 1.6 kHz / mA (vert. Plane)40 Bunche mode: 2.5 mA bunch current
vert. Feedback can excite the low intensitysattelite bunches at their betatron tune
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 21
Clearing procedure: impact on beam line signals
User Run 2016: successful satellite bunch clearingusing the multi bunch feed back systemwith neglectable impact for the beam lines
automatic procedure at every top up injection
was development in close collaboration
withthe beam lines *), the feedback group, the softwaregroup, the Preaccelerators (DESY II, Linac, Pia)
Signal from beam line P10 (counts per second)drop by ~ 25 % is not acceptable for someexperiments. further optimization with reduced kick amplitude and sweep range (tune frequency range)
current
zoomsignal
*) Beam line P01: O. Leupold, H.-C. Wille
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 22
Emittance Diagnostics
North: interferometric measurementdipole radiation(originally set up for a bunchlength measurement)
Von Laue Hall:Diagnostic Beam Line
South East: new diagnostic station
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 23
Emittance Diagnostics in SE
South East: new diagnostic station
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 24
PETRA III Schedule: User Run, April 7 – Dec 22, 2016
Typical week: 168 h user run, Monday … Wednesday 7 h , Thursday 7 h … SundayWednesday: maintenance or short study period + Test run starting at ~ 20 h … 23 h
2016 Jan Feb March April May June July Aug. Sep. Okt. Nov. Dez.
1 Interlock Line MDT 1 MDT2 Test Set-up 2 MDT3 3 MDT4 Shut MDT/Test MDT 4 Service5 Down MDT/Run 5 Week6 MDT 6 MDT MDT7 Technical USER 7 MDT MDT MDT8 start up RUN MDT 8 Service9 9 Week MDT10 1011 MDT 1112 12 MDT13 MDT 13 MDT14 14 MDT Service MDT15 MDT MDT 15 MDT / Week16 MDT 16 Test17 MDT Service 17 Runs18 MDT Week 1819 MDT 19 MDT20 MDT MDT 20 MDT21 MDT 21 MDT MDT22 MDT MDT 22 MDT / 23 MDT 23 Test MDT Shut24 Beam 24 Runs Down25 Line MDT 2526 Set-Up 26 MDT27 MDT Service 27 MDT28 Week 28 MDT29 MDT 2930 MDT MDT 30 MDT31 Beam 31 MDT
95.2 %MTBF 37 h
Test Runs / Studies
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 25
P 24 Chemical crystallography
P 21 High-energy X-ray materials science
P 23 Nano diffraction
P 22 Nano spectroscopy
PETRA III: Beamlines in hall East – Further plans
Front end components for the photon beam lines P 22, 23, 24 have been installed in the East hall during the last shut down 2015/16.
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 26
Tentative schedule and plans 2017
Shut down 2017 Jan / Feb / March installation of a chicane in the straight section east preparation for the installation of an In Vacuum Undulator survey / realignment of the accelerator components installation of the undulators PU 22, 23 and 24 new coil configuration for PDE magnets
Shut down 2017 July / Aug installation of an new absorber in the wiggler section North
installed in 2015
Number ID Type Energy range (keV) Cell
PXE P21 4 m U21 (IV) 40 -150
2 m U29 52, 85, 100 P22 2 m U33 2.4 - 15 1 P23 2 m U32 5 - 35 1 P24 2 m U29 8, 15 - 44 2 P25 2PXN P61 10 x 4 m Wiggler 40 - 200 P62 1 P63 1 P64 2 m U33 4 - 44 2 P65 0.4 m U33 4 - 44 2 P66 Dipole 4 eV - 40 eV
front end components installed in 2015/16
2017: installation of undulators,realignment of accelerator components
2017: installation of a chicane,and front end components
2017 July: new absorber + front endcomponents
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 27
In-vacuum undulators
Number ID Type Energy range (keV) Cell
P01 10 m U32 (2 x 5 m) 5 – 40
P02 2 m U23 20 – 100 1
P03 2 m U29 8 – 25 1
P04 4 m U65 (APPLE) 0.2 – 3.0 2
P05 2 m U29 8 – 50 3
P06 2 m U32 2.4 – 50 3
P07 (option
low beta)
4 m U19 (IV)
(pres. 2m)
50 – 300 4
P08 2 m U29 5.4 – 30 5
P09 2 m U32 2.4 – 50 5
P10 5 m U29 4 – 25 6
P11 2 m U32 8 – 35 7
P12 2 m U29 4 - 20 7
P13 2 m U29 5 – 35 8
P14 2 m U29 5 - 35 8
High βx
Low βx
High beta: ββββx = 20 m ββββy = 4 mLow beta : ββββx = 1.4 m ββββy = 4 m
Max von Laue Hall: 14 beam lines8 DBA cells ( length 23 m)
PETRA III: 14 Beamlines in the Max von Laue Hall
Two in-vacuum undulators(One undulator for P21)
have been ordered
delivery of the first undulatoris scheduled for 2017
another one is foreseen for P07
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 28
PETRA
PETRA:
2007-2009 PETRA II PETRA III2014/15 PETRA III Extension2017 Extension Phase 2 + 3
>2025 Major Upgradetowards a diffractionlimited synchrotronradiation facilityPETRA IV
• Upgrade plans - PETRA IV
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 29
X –rays diffraction limit
uncertainty relation:
For photons:
intrinsic diffraction-limited emittance:
Beam emittance = intrinsic diffraction-limited emittance of the photons
Vertical emittance at PETRA III 10 … 20 pmcorresponds to diffraction-limited emittance hard X –Rays
0.126 nm … 0.251 nm or9.8 keV … 4.9 keV
Upgrade Plan:also achive a very small horizontal emittance (10 pm … 30 pm)
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 30
Upgrade plans (> 2025): PETRA IV
PETRA IV Parameter
Energy 5 GeV (4.5 – 6 GeV)
Current 100 mA (100 – 200 mA)
Number of bunches ~ 1000
Emittance horz. 20 pm rad (10 – 30 pm rad)
vert. 20 pm rad (10 – 30 pm rad)
Bunch length ~ 100 ps
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 31
PETRA IV - project preparation phase
Study group in theAccelerator Divisionwith threeworkpackages:
2.01 Lattice Design
2.02 Injectors
2.03 Technical design
PETRA IV Jan. Feb. März April Mai Juni Juli Aug. Sep. Okt. Nov . Dez.2016 Study group Studies
2017 LatticeDesign
2018 CDR
2019 TDR
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 32
Design Strategy
Lattice Design
Injectors
Technical design
scaling the ESRF cell PETRA IVfirst approach for a cell in the experimental halls
arc cells without undulators modified ESRF cell cell with phase advance of π π π π between sextupoles and
double twist in 4D-phase to enable chromatic corre ction in both planes
Design goal: dynamic acceptance sufficient for accu mulationor for the beam from the existing injector
Design goal: reuse the injector chain
studies to improve emittance investigation of the technical requirements to main tain operation until 2045 studies toward a new injector
Investigation of the technical limits and possibili tiesat an early stage before a lattice design is finali zed
magnet design: design studies of quads, combined fu nction magnets anddipoles with longitudinal gradient
girder design: investigation of concepts with new m aterials, studies of alignment and installation concepts
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 33
PETRA IV – lattice design studies
Scaling of the ESRF cell
length 26.374 m → 23.013 mfactor 0.91 applied to magnets anddrifts
bending angle 11.25° → 5°factor 0.44
rematching the opticphase advance betweensextupoles to maintain ∆µx=3π, ∆µy= π
several variantsa) βx= βy=1.8 m, Dx=0 m @ IDs
b) βx= 6.9 m βy=2.65 m (ESRF)
ESRF II
PETRA III
PETRA IV
arc geometryPETRA and ESRF
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 34
Scaled ESRF cell ( Dx > 0 @ IDs)
> Scaled length of all elements to the P3-cell length of 23 m and changed bending angle from 11.25 ° to 5° (also lo ng. gradient dipoles)
> εx = 8 pm·rad at 5 GeV, 11 pm·rad at 6 GeV
> But: dispersion bump is a factor of ~3 smaller→ sextupole strength ~3 times higher compared to ESR F!
0 5 10 15 200
5
10
15
20
Betafunctions [m]
-0.06
-0.05
-0.04
-0.03
-0.02
-0.01
0.00
0.01
0.02
0.03
Dispersion [m]
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 35
ESRF cell @ 6 GeV
Quadrupoles:
At the edges: ~50 T/m
Near center: ~85 T/m
In CF dipoles: ~34 T/m
Sextupoles:
~1700 T/m2
Octupoles:
~51000 T/m3
Comparison of Magnet Strength
Scaled ESRF cell @ 5 (6) GeV
> Quadrupoles:
At the edges: ~60 (72) T/m
Near center: ~100 (120) T/m
In CF dipoles: ~38 (46) T/m
> Sextupoles:
~4000 (4800) T/m2
> Octupoles:
?
Source: Orange Book ESRF UpgradeMagnet constraints at ESRF: g < 91 T/m, m < 4.3 kT/m2, o < 70 kT/m3
Magnets are shorter due to scaling→ less space for additional elements
Dispersion bump2.5 x smaller
Length scaling:26 m/23 m = 1.13
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 36
950 1000 1050 1100 11500
5
10
15
20
25
30
35
Betafunctions [m]
-0.07
-0.06
-0.05
-0.04
-0.03
-0.02
-0.01
0.00
0.01
0.02
0.03
Dispersion [m]
Optics of Arcs
9 ESRF cells, 207 m, 45°
Matched to zero dispersion
~3.5 cm
~25 m
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 37
Parameter Value
Energy E 5 GeV
Tunes Qx, Qy 187.77 / 72.26
Circumference C 2348 m
Nat. Chromaticity ξx, ξy -394 / -212
Mom. Compaction factor α 1.2·10-4
Energy spread σE 0.56·10-3
Nat. Emittance ε0 9 pm·rad
Damping times τx,τy,τe 82, 121, 81 ms
Energy loss/turn ∆E 643 keV
Parameters of the scaled ESRF Lattice
-8 -6 -4 -2 0 2 4 6 8X [mm]
0
2
4
6
8
10
12
14
16
18
Y [mm]
> 512 Turns, no errors
> εx = 9 pm·rad, βx = 21.4 m, βy = 20.9 m, Dx = 0 mm
> Physical aperture 20 mm
> Ax = (2.5 mm) 2 / 21.4 m = 0.29 mm·mrad
> Ay = (5 mm) 2 / 20.9 m = 1.2 mm·mrad
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 38
Phase space exchange solution
y <---> x
x <---> y
Exchange x y
SF SD
same cell type willcorrect horz. and vert.chromaticity in differentsections of the ring
∆φ∆φ∆φ∆φx=π=π=π=πSF SF
• Similar to Moebius scheme, with two phase space exchanges in the rings
• Allows non-interleaved sextupole scheme with π/π phase advance: large DA
Lattice design
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 39
Ring with a double twist, dynamic aperture
on momentum aperture ~ 4 mm mrad, or 20 mm at ββββ = 100 menergy acceptance ~ 2.4 %
Lattice Version 0 without undulator sections
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 40
Optics version 1 (with undulator insertions)
• arc cells with non interleaved sextupoles
• Scaled ESRF cells in two octants• extension halls not yet included• emittance ~ 20/20 pm (5 GeV)
Lattice Version 1combination:
not an optimal solutionsmall dynamic aperture
new undulator cell under development
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 41
Injectors
Design goal: reuse the injector chain
Linac IIS-Band Linace- e+ converter (presently not used)two guns (bombarder type + triode)
PIAaccumulator ring (designed for e+ operation)
DESY II 450 MeV 7 GeV, Emittance (6 GeV, PETRA III) ~ 350 nmIntensity: max. 2 x 1010, typical 1 x 1010
(for PETRA III top-up 40 bunch mode: 5 x 109
To maintain operation of the injector complex until 2045 requires certainlya careful review of all technical subsystem and the required investments.
Studies have started on the possibilities to improv e the DESY II emittance
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 42
DESY II emittance versus horz. tune (6 GeV)
NN
6 7 8 9 10 110
100
200
300
400
500
600
Qx
ε x / n
m*r
ad
large dispersion
working point withbest emittance~180 nm·rad
presently usedworking point320 nm·rad
localminimum~280 nm·rad
QF QD SFSD
optic
E = 6 GeVQy = 5.7
natural chromaticities at the 3 working points:
ξ ξ ξ ξ X=-7 ξ ξ ξ ξ X=-8 ξ ξ ξ ξ X=-17
The presently installed quad power supplies do not allowan operation at working point 3 with full energy.
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 43
Technical Design
Magnet design: collaboration with NIIEFA, Efremov i nstitute
Study of a dipole quadrupole magnet for PETRA IV
Strategy : Investigation of the technical limits and possibilitiesat an early stage before a lattice design is finali zed
auxiliary coil
main coil
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 44
Study of a dipole quadrupole for PETRA IV
Magnetic field B yx: 6 mm … 18 mm, y = 0,G = 46.6 T/m
First 2D simulations of a combined function magnet
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 45
Collaborations
Collaborations:
• ESRF: support with lattice data for ESRF upgrade
• Mikael Eriksson (Lund, MAX lab)has joined the PETRA IV project preparation as a ge neralist from June 2016
• Efremov institute - DESY collaboration: magnet design
• SLAC – DESY collaboration (meeting July 2016)support with lattice data for PEPX (SLAC-PUB-14785)
considered topics for a collaboration: lattice theory, impedance and collective effects
Collaborations are necessary to handle all the acti vities related to PETRA III and PETRA IV:
R. Wanzenberg | SLAC visit, Oct 10-13, 2016 | 46
Thank you for your attention !