Status of the Rare Isotope ReAccelerator Facility ReA , Slide 1 Facility ReA D. Leitner on behalf of the ReA team at Michigan State University
Status of the Rare Isotope ReAccelerator Facility ReA
, Slide 1
Facility ReAD. Leitner
on behalf of the ReA team atMichigan State University
Outline
• Introduction
• ReAcclerator facility
• Commissioning Results and Status
• First radioactive ion beam delivery
NSCL/FRIB Laboratory
, Slide 2
FRIB Accelerator Complex Subsystems
ReAccelerator Facility
, Slide 3J. Wei, NA-PAC'13 FRYBA1
Isotope production reaction mechanisms [1]
ISOL –Isotope Separator On-Line (target “spallation” or fission)– Light ion-induced “spallation” or fission of heavy targets – Isotopes must diffuse from hot targets and effuse to an ion source– Typical beams ~100-1000 MeV protons; typical targets Ta & UC– Photofission using high power electron linac
Most post accelerator facilities are based on
Stopped
, Slide 4
Production Accelerator
Thick Hot Target
Target/Ion Source
Stopped Beams
PostAccelerator
Isotope/Isobar Separator
Several facilities around the world:Rex-Isolde, Spiral, ISAC, EXYPT, SPES,EURISOL …
• Very intense beams of many elements, especially noble gases and alkalis
• Weak beams of refractory and chemically active elements
D. Leitner NA-PAC 2013, slide 4
Isotope production reaction mechanisms [2]
• In-flight heavy-ion fragmentation or fission on a l ight target– Fragments of the beam are kinematically forward directed at ~beam velocity– Rare isotopes are separated physically; no chemical dependence– Typical heavy ion beams are 18O- 238U at 200-2000 MeV/u; typical targets Be or C
Fragment Separator
Stopped BeamsGas or Gas or
Solid Fast • Separated beams of any
species including refractory and
, Slide 5
ReA at MSU is the first post-accelerator coupled to a fragmentation facility
Production Accelerator
SeparatorPost
AcceleratorStopper
Solid Stopper
Fast Beam
Thin Production Target
species including refractory and chemically active elements and isotopes with very short half-lives, even isomers
• Needs gas catcher or solid stopper for post acceleration
D. Leitner NA-PAC 2013, slide 5
CCF Is The Only Facility In The World That Provides Fast, Stopped, And Reaccelerated Beams Of Rare Isotopes
Gas StopperK500 Cyclotron
MoNALISA
Sweeper Magnet
SECAR (design)JENSA
ANASEN, FSU SuNCFFDJANUS..
Momentum Compression Beam Line)
BECOLA
AT-TPC
Cycstopper off line commissioning
20 meter
ReA3 Hall
ReA6-12Hall
LEBIT,Minitrap
, Slide 6
Fast BeamsFast Beams Gas StopperGas Stopper Stopped beamsStopped beams Reaccelerated BeamsReaccelerated Beams
Space for future expansion of the science program
ReAccelerator Facility
A1900 Fragment Separator
K1200 Cyclotron
SEETFSeGAHiRATriplex Plunger CAESARLENDAGRETINA (DOE national user facility)
BCSNERO DDASCAESAR
RFFS
S800
D. Leitner NA-PAC 2013, slide 6
In-flight Fragmentation Offers A Wide Variety Of Rare Isotopes
At the Coupled Cyclotron Facility at MSU (≈10 years of operations)
more than 1000 RIBs have been produced and more than 870 RIBs have
been used in experiments with > 90% availability
Average experiment: primary beam 120 hrs, several secondary RIB beam changes
ReA SC Post-Accelerator – 3 stages(41 SC SRF cavities)
Achromatic Mass Sep
RT RFQ80.5 MHZ RT RFQ
MHB
1+→n+
Mass
separation
Gas
Stopper
Experiments
ReA3 (15 cavities)(2014)
ReA6(+10 cav.)
(2015)
ReA12(+16 cav.)proposed
ReA12(+16 cav.)proposed
Fast
RIB
, Slide 8
Requirements : Variable energies 300keV/u – 12MeV/u
Ionization efficiency for all elements
> 20 % EBIT charge breeder + high efficiency linac
Beam rate capabilities 108 ions/sec Hybrid EBIS/T charge breeder
High beam purity A1900, EBIT CB, Q/A
Low energy spread, short pulse length
1keV/u, 1nsec Multiharmonic external buncher and tight phase control in SRF linac
Stopper RIB
D. Leitner NA-PAC 2013, slide 8
Rare Isotope Beam Production
40Ca primary beamAt 140MeV/u
Production rate ~1.3E5 PPS/pnA,
Purity for K-37 ~ 50%
dp/p = 0.5%D. Leitner NA-PAC 2013, slide 9
Rare Isotope Beam Thermalization : RIB Beams Gets Further Purified
ANL 1.2 m long linear gas cellHigh purity helium: ~ 90 Torr, -50CThermalizes RIB ions to < 1eVSingly and doubly charged
Rat
e (c
ps)
Variable degrader and wedge for further purifying the beam
94% 37K+
Second gas catcher or cyclotron stopper
Electrostatic Transport Line at 60keV
Analyzing Magnet
mass
D. Leitner NA-PAC 2013, slide 10MOPMA07, J.A. Rodriguez et al, “The D-Line Project at MSU”
Rare Isotope Beam Thermalization Station
Commissioned 2012/2013
D. Leitner NA-PAC 2013, slide 11
ReA Design Choices: EBIT Charge Breeder
0.085 moduleFY14
0.041 modulesRT RFQ
MHB
Achromatic Mass Separator
Pilot source for linac tuning
n+ RIB beamn+ RIB beam
EBIT1+ RIB beam
D. Leitner NA-PAC 2013, slide 12
EBIT:
• Short breeding time• High ionization efficiency• Charge state flexibility• Low beam contamination• 0.5 ≥ Q/A ≥ 0.2
Charge Breeding In The EBIT Source
Radial electron-beam
Highly charged ions
Trap electrodes
Magnetic field
Electron
collector
Electron
gun
Electron
beam
Continuous injection and
accumulation (~100 ms)
A+
Pulsed extraction (100 µs to ms)
AQ+
q+ q+
V1+1+
2+2+
Pulsed extraction
1+1
Radial electron-beam
space-charge potential
Axial potential well from the trap electrodes
Over-the-potential barrier injection Lower-the-barrier extractionV
Continuous injection D. Leitner NA-PAC 2013, slide 13
EBIT Background Spectrum And Selection Of 37K Charge States
200
250
300
350
400
Ana
lyze
d C
urre
nt [
pA]
H2+
16O
7+
14N
6+
16O
6+
14N
5+
Ar10
+ ,12
C3+
16O
5+
14N
4+
0
50
100
150
200
2 2.5 3 3.5 4
Ana
lyze
d C
urre
nt [
pA]
Mass/Charge Ratio (A/Q)
37K
18+
37K
17+
37K
16+
12C
6+
40A
r16+
37K
19+
37K
15+
37K
14+
37K
13+
37K
12+
37K
11+
37K
10+
37K
9+
12C
4+
40A
r14+
16O
4+, 40
Ar
40A
r13+
40A
r12+
40A
r11+
D. Leitner NA-PAC 2013, slide 14
Background ion intensities from the charge breeder in the region of interest are less than 1 pA
10
100
Ana
lyze
d C
urre
nt [
pA]
K19
+
37K
18+
37K
17+
37K
16+
H2+
15N
7+
16O
7+
14N
6+
12C
6+
40A
r17+
18+
0.1
1
1.8 1.9 2 2.1 2.2 2.3 2.4
Ana
lyze
d C
urre
nt [
pA]
Mass/Charge Ratio (A/Q)
37K
37 37 37
13C
6+
40A
r18+
D. Leitner NA-PAC 2013, slide 15
0.085 moduleFY14
0.041 modulesRT RFQ
MHB
Q/A
Pilot source
ReA Design Choices: RT -RFQ With External Buncher And High Efficiency SC -Linac
n+ RIB beam
, Slide 16
EBIT1+ RIB beam
SRF LINAC� 80.5 MHz RF frequency�Flexible energy range (deceleration 300keV/u to maximum linac energy in small steps�External multi harmonic buncher to minimize the longitudinal emittance
D. Leitner NA-PAC 2013, slide 16
Room Temperature Radio Frequency Quadrupole (RFQ )
• Pulsed operation (160kW, 25%)• Energy Boost: 12 keV/u - 600 keV/u• 4-rod structure, 92 cells, 3.3 m long• Buncher : 80.5MHz, 161MHz, (241.5 MHz)• Nom 82 % beam capture measured
Longitudinal acceptance (white area)
Beam at the entrance of
MHB
Beam at the entrance of RFQ
0
100
200
300
400
500
600
700
880 890 900 910 920 930 940 950
Cou
nts
(arb
.uni
t)
nsec
FWHM0.52 nsec
12.54 nsec
Beam bunch after RFQ
D. Leitner NA-PAC 2013, slide 17
Q. Zhao et al., PAC’07; D. Leitner et al, PAC’11; W. Wittmer et al., NA-PAC’13 (MOPSM07)
Compact Superconducting Linac With 2 Types Of Quarter Wave Resonators
• 7 β=0.041 cavities are in operation since 2010 with excellent performance and stability
• Routinely operated at 160% of the specified gradient
Measured Phase and Amplitude Stability
Cavity Phase Std Amplitude Std
, Slide 18
Cavity Phase Stddev (deg)
Amplitude Stddev (%)
82 0.149 0.025 %
84 0.207 0.009 %
85 0.043 0.018 %
88 0.14 0.013 %
89 0.06 0.020 %
91 0.248 0.046 %
D. Leitner NA-PAC 2013, slide 18
D. Leitner et al., SRF'2011
Compact Superconducting Linac With 2 Types Of Quarter Wave Resonators
• Cryomodule 3 will be installed and commissioned in the in 2014
• β=0.085 cavities were redesigned to reliably provide high gradient acceleration fields
cavitysolenoid
1010
SC248SC249SC251SC252
0 10 20 30 40 50
β = 0.085 quarter-wave resonator test results
Epeak
(MV/m)
• Eleven β=0.085 cavities have been tested (all tested well above specifications)
• CM4 (FRIB prototype) 2015, novel bottom up design
solenoid
D. Leitner NA-PAC 2013, slide 19FRYBA1, J. Wei et al, “Progress towards the Facility for Rare Isotope Beams”A. Facco et al., IPAC'2012
108
109
0 2 4 6 8
SC252SC253SC254SC256SC255
Qua
lity
Fac
tor
Eacc
(MV/m)
ReA6
(4K)ReA3 (4K)
4K
Diagnostic Systems Are Very Challenging For RIB Post-accelerators (Dynamic Range 10 pps To 1012 pps)
1, 2, 3, 4, 5, 6, 10
Diagnostics
1 FC
2 Slit profile monitor
3 Viewer, MCP or crystals
4 Bunch lengths, timing
5 Slits, aperture
6 Attenuators
1, 2, 4, 5,7 1, 2, 3 4,5
7,12
12 1, 2,
1, 2, 3, 4, 5, 6
1,2, 4,9,
11, 7
1,3,8
1,2, 3,7,8
6 Attenuators
7 Detectors (decay, scattering, in beam)
8 MCP, TOF
9 Pepperpot
10 Emittance Scanner
11 Energy defining slits
12 BPM
12 1, 2, 5, 4
1, 11
1, 2, 5 4, 7
1,3,8
ReA linac has a lot beam diagnostics to support the wide range of beam intensities
D. Leitner NA-PAC 2013, slide 20
ReA Beam Line Is Well UnderstoodDesign compares well with the actual tuning paramet ers of the beam line
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
A1900
Beam Envelope
MOPSM07, W. Wittmer et al.
Linac transmission RIB beams≈ 70%
The ReA Linac (CM1+CM2) Was Characterized Using Stable Beams
• Absolute energy calibration of ReA using 992 keV Al(p,γ) resonance
• Linac was tuned in 2keV energy steps• Measured energy spread of 0.5% FWHM is close to
predicted value
L. Ling-Ying et al., manuscript under preparationD. Leitner NA-PAC 2013, slide 22
CAESAR Detector Array
For Rare Isotope Beam Operations Pilot Beams Are Used To Pre-tune The Linac
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
0
10
20
30
40
50
0 20 40 60 80 100
Cou
nts
Energy [MeV]
241Am calibration source
16O5+ 40Ar13+
87Rb28+
A1900
MOPSM07, W. Wittmer et al.
Pilot Beam
For Rare Isotope Beam Operations Pilot Beams Are Used To Pre-tune The Linac
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
0
10
20
30
40
50
0 20 40 60 80 100
Cou
nts
Energy [MeV]
241Am calibration source
16O5+ 40Ar13+
87Rb28+
A1900
MOPSM07, W. Wittmer et al.
Pilot Beam
Background Ion from EBIT
For Rare Isotope Beam Operations Pilot Beams Are Used To Pre-tune The Linac
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
0
10
20
30
40
50
0 20 40 60 80 100
Cou
nts
Energy [MeV]
241Am calibration source
16O5+ 40Ar13+
87Rb28+
A1900
MOPSM07, W. Wittmer et al.
Pilot Beam
Charge Bred BeamRb+ → Rb28+
from the EBIT
For Rare Isotope Beam Operations Pilot Beams Are Used To Pre-tune The Linac
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
A1900
15N7+, A/Q=2.1428
MOPSM07, W. Wittmer et al.
0.1
1
10
100
1.8 1.9 2 2.1 2.2 2.3 2.4
Ana
lyze
d C
urre
nt [
pA]
Mass/Charge Ratio (A/Q)
37K
19+
37K
18+
37K
17+
37K
16+
H2+
15N
7+
13C
6+
16O
7+
14N
6+
12C
6+
40A
r17+
40A
r18+
For Rare Isotope Beam Operations Pilot Beams Are Used To Pre-tune The Linac
EBIT CB
RFQ
CM2
CM3 (2014)
CM1SECAR
AT-TPCD-LineN4 Stopped beams
First RIB beam delivered
Low Energy Experimental hall
A1900
15N7+, A/Q=2.142813C6+, A/Q=2.1667
MOPSM07, W. Wittmer et al.
0.1
1
10
100
1.8 1.9 2 2.1 2.2 2.3 2.4
Ana
lyze
d C
urre
nt [
pA]
Mass/Charge Ratio (A/Q)
37K
19+
37K
18+
37K
17+
37K
16+
H2+
15N
7+
13C
6+
16O
7+
14N
6+
12C
6+
40A
r17+
40A
r18+
37Cl
Ene
rgy
Loss
[A
.U.]
Radioactive Ion Beam Measured In The ANASENIonization Chamber
37Cl
37K
Ene
rgy
Loss
[A
.U.]
Contaminant beams in same setting as 37K17+
Reaccelerated 37K RIB
Cl
13C
Energy [A.U.]
Ene
rgy
Loss
[
Cl
13C
Energy [A.U.]E
nerg
y Lo
ss [
First radioactive ion beam delivery to user 8/20/2013!
Summary
• ReA is the first post-accelerator coupled to a fragmentation facility
• The EBIT charge breeder provides high purity beams
• The SC cavities perform above specification and have been operated reliably since 2010
• Commissioning and final installations are progressing well, RIB • Commissioning and final installations are progressing well, RIB beams below or close to the Coulomb barrier(light ions) will available for users in 2014
• The first radioactive ion beam was delivered to users in August of 2013
• ReA will serve as post accelerator for FRIB
Co-authors
D. Leitner1,2, D. Alt2, T. M.Baumann2, C. Benatti2, B. Durickovich1, K. Kittimanapun2, A. Lapierre2, L. Ling-Ying, S. Krause2, F. Montes2, D. Morrissey2, S. Nash2, R. Rencsok2, A. Rodriguez1, C. Sumithrarachchi2, S. Steiner2, S. Schwarz2, M. Syphers2, S. Williams2, W. Wittmer1, X. Wu1
1Facility for Rare Isotope Beams, Michigan State University,
, Slide 30
1Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824 USA2National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA