1. RIKEN Nishina Center for Accelerator-based Science
RI Beam Factory Project at RIKEN
H.Sakurai
RIKEN Nishina Center for Accelerator-based Science

2. Overview of RIBF facility and physics with exotic nuclei
Introduction of Phase-I facility and Experimental programs
Recent achievements and future plan
Summary

3. RIBF Facility Layout Phase-II Experimental Installations
2007~2010 (plan)
Existing facility
RIPS
SHE
GARIS
~100 MeV/u
~5 MeV/u
RILAC
AVF
fRC
RRC
SRC
IRC
BigRIPS/ZeroDegree
CRIB (CNS)
~10 MeV/u
MeV/nucleon
New facility
Phase–I
SRC + BigRIPS/ZeroDegree
440 M$ (1$=100JPY)
350 MeV/nucleon
up to U
1st beam in 2006

4. Exploration of the limits of nuclear existence
- towards the drip-lines -
3rd generation of RI beam facility “Fission fragment of U”
SRC high energy and intense heavy ion beams upto U
350 – 400 A MeV Goal of intensity 1 p-micro A
BigRIPS high acceptance for fission fragments
Projectile fragmentation
48Ca, 58Ni, 78Ge, 78Kr,
112Sn, 204, 208Pb, 238U, ...
350~400A MeV
proton-rich side
neutron-rich A<50 or A>160
limit of production
1 particle/day
Fission
238U 350A MeV
neutron-rich side 20<Z<60
wide dynamic range
78Ni ~10 particles/sec goal

5. Phase-II construction 2007-2010
To maximize the potentials of intense RIBs available at RIBF
60 M$
SCRIT - e-RI collision
Wakasugi, Suda et al.
SAMURAI - large acceptance
Kobayashi et al.
Rare RI Ring – mass
　　Ozawa et al.
SHARAQ - high resolution
Shimoura et al.
in 2008
SLOWRI- slow beams
Wada et al.
RI Spin Lab. at RIPS –pol. RI beam Ueno et al.
About 2M $ was approved in FY2007 for the infrastructure, radiation shields, ZeroDegree electronics.

6. Acceleration Flow in RI Beam Production
RILAC
RRC
fRC
IRC
SRC
BigRIPS
ZDS
by Narumasa Miyauchi 6

7. BigRIPS /ZeroDegree
Exploration into “Isospin Frontier” toward the drip-lines
Reaction study fit for high energy domain A MeV
operated by Kubo group
BigRIPS Fragment Separator
high acceptance for fission fragments
pid for RI beams at the second section
ZeroDegree Multi-function BT line
pid for ejectiles in inclusive- and semi-exclusive measurement
medium resolution (p/dp ~ 2000 – 4000)
Experimental set-ups
PID section
RIB production
PID section

8. Basic parameters of BigRIPS
T. Kubo et al.
Configuration Two-stage separator
First stage Two bends
Second stage Four bends
Energy degrader Achromatic wedge
Quadrupoles Superconducting
Angular acceptance
Horizontal mr
Vertical mr
Momentum acceptance %
Max. magnetic rigidity Tm
Total length m
Momentum dispersion*
First stage m
Second stage m
Momentum resolution**(1st order)
First stage
Second stage***
In-flight fission of 238U at 350 MeV/u
~ 100 mr
~ 10 %
* At the mid-focus of the stage.
** Those in the case when a 1 mm beam spot is assumed.

9. Specifications of optical modes
(I) Achromatic: Large acceptance mode
Maximum magnetic rigidity = 7.3 Tm
Angular acceptance Horizontal = +/-45 mrad, Vertical = +/-30 mard
Momentum acceptance = +/-3 %
Momentum dispersion = 2.24 cm/%
Momentum resolution = (X,P)/(X,X) =1240
(II) Achromatic: High resolution mode
Maximum magnetic rigidity = 9.0 Tm
Angular acceptance Horizontal = +/-20 mrad, Vertical = +/-30 mard
Momentum acceptance = +/-3 %
Momentum dispersion = 2.12 cm/%
Momentum resolution = (X,P)/(X,X) = 2120
(III) Dispersive spectrometer mode
Maximum magnetic rigidity = 9.0 Tm
Angular acceptance Horizontal = +/-20 mrad, Vertical = +/-30 mard
Momentum acceptance = +/-2 %
Momentum dispersion = 4.13 cm/%
Momentum resolution = (X,P)/(X,X) = 4130
(IV) Transmission mode

10. Phase-I programs at BigRIPS/ZeroDegree 2007~
Rare-Isotope Physics Programs
Fast RI beam production to search for new isotopes
Global survey to search for anomalous regions
Specific programs with deuteron beams
BigRIPS in-flight production of fast rare-isotope beams
Ground state properties and low lying excited states
via decay spectroscopy / transmission method:
particle stability, T1/2, Qb, sR, Ex.(2+)...
Deeply bound pionic states via (d, 3He) at 500 MeV
Three-body force via pol. d+p elastic scattering at 700 MeV
ZeroDegree multi-function beam line for inclusive/semi-inclusive measurements
　　production of 3rd RI beams
Collectivity and matter distribution
via in-beam gamma / missing mass spectroscopy
One step energy regime 200~300 A MeV
B(E2), B(M1), (p,p), (p,p’), Ex....

11. RIBF layout in 2007-2008 in-beam gamma spectroscopy
missing mass spectroscopy
RIBF layout in
(Phase-I layout)
b-spectroscopy
total reaction cross sections
(d,3He)
Pol.d+p
ZeroDegree Spectrometer
Experimental set-ups
ZDS: Zero-Degree forward Spectrometer

12. RI beam intensities at BigRIPS for first two years 2007-2008
Primary beam energy 350AMeV
48Ca (200pnA), 86Kr (100pnA),136Xe (10pnA), 238U(2pnA)
Secondary beam energy ~250A MeV
Cross sections Fragmentation EPAX-II
Fission GSI-data (U+Be), ABRABLA (Coulomb)

13. Collaboration
One of the largest heavy-ion facilities in the Asia/world
Open for the world-wide user community
International Collaboration Workshop on Experiments at the RIBF
6th-9th November 2006
~130 participants; ~30 from foreign institutes/universities
Presentation and discussion of experimental projects to be done in collaboration
To identify common interests
To have “show case” for experimental technique, methods, detectors …
To establish collaborations
To prepare proposals
MOU
“Creation of the council
for China-Japan Research Collaboration on Nuclear Physics”
10th November 2006
19 proposals submitted to PAC Feb (74% international)
France-Japan collaboration will be established soon

14. Recent achievements / Future plan

15. Recent achievements 28th Dec. 2006 First Beam 27Al10+ at RIBF-SRC
Mar. 2007
12th Kr31+ beam at 345 A MeV several pnA.
13th First Production of RIBs at BigRIPS
23rd First successful acceleration of 238U beam 0.002pnA
27th First production of radioactive isotope
beams via a U beam
Last week
238U beam 0.02pnA max
BigRIPS Commissioning;
New isotope 125Pd

16. First beam accelerated at SRC K2600MeV
16:00 28th Dec., 2006
27Aｌ MeV/u

17. First RIB 13th Mar. 2007 Kubo et al. 86Kr + Be(2mm) at 345 MeV/u DE
N=Z+2
N=Z+1
86Kr + Be(2mm) at 345 MeV/u
N=Z+3 Zn Cu Ni Co
54Fe
N=Z Fe Mn Cr V Ti
43Sc Sc K Ca Cl Ar P S Si Al
TOF (F3-F7)
Kubo et al.

18. PID for isotopes created via a 345 A MeV U beams w/o degrader
TOF(F3-F7) [ns]
[MeV] Xe
Mar. 27th, 2007 I
Sn (Z=50) Sb
132Sn Cd In Pd
117Rh Ag Ru
Rh (Z=45) Mo
Zr (Z=40) Tc
104Zr Nb Sr
98Y Y Kr
91Br Rb Se
Br (Z=35) Ge
82Ge As
Zn (Z=30) Ga
76Zn Ni Cu Co
70Ni Fe
T. Kubo et al.

19. Z Z A/Q A/Q The first test experiment at RIBF 238U86+ 345 MeV/u
～ 1enA on Target Z
Bρ: Tm
Target: Be 7mm
Total dose: ~1×1013
Total time: 25.4 hours
Z=46 Z
A/Q
A/Q
M.Bernas et a. PLB 331(94)19; PLB 415(97) 111

20. Discovery of 125Pd A/Q Cf. 124Pd 19 counts, 125Pd(cand.) 1count
A/Q resolution(r.m.s): 0.07%
At Z=40
A/Q
Cf. 124Pd 19 counts, 125Pd(cand.) 1count
at GSI, 1997 PLB 415, 111 (97)
total dose ~1x108

21. Setup for May-2007 Commissioning
Double Achromatic
PL 0.2mmt
PPAC(x,y) x2
Silicon 0.33 mmt x2 for DE
NaI for E
Clover for isomeric states
Setup to search for new isotopes
Double Achromatic
PL 0.2mmt
PPAC(x,y) x2
Mom. Slit
Dp/p=2%
(Max 6%)
W/o Wedge Br
TOF
Prod. Target Be 7mmt
Beam-intensity monitor
PL 1mmt x 3
Momentum Dispersive
PPAC(x,y) x2

22. Collaborators RIKEN Nishina Center T. Kubo (Spokesman), T. Ohnishi,
K. Yoshida, A. Yoshida, K. Kusaka, N. Fukuda, M. Ohtake, Y.Yanagisawa,
H. Takeda, Y. Yamaguchi, N. Aoi, K. Yoneda, H. Otsu, S. Takeuchi, D. Kameda,
T. Sugimoto, Y. Kondo, K. Tanaka, H. Scheit, Y. Gono, T. Motobayashi,
H.Sakurai
OECU, Osaka Y. Mizoi
Rikkyo Univ M. Matsushita
Univ. of Tokyo H. Suzuki, T. Nakao, H. Kimura
Saitama Univ T. Kuboki, T. Yamaguchi
Tsukuba Univ A. Ozawa, T. Moriguchi, Y. Yasuda
Tokyo Inst. Tech. T. Nakamura, T. Nannichi, T. Shimamura, Y. Nakayama
GSI H. Geissel, H. Weick
ANL J. Nolen
NSCL/MSU O.Tarasov, T. Nettleton, D. Bazin, B. Sherrill, D. Morrissey
GANIL W.Mittig

23. Future plan
2007
18th June-
Accelerator + BigRIPS Commissioning w/ U beam
Sept.(plan) RIBF PAC
At the beginning of Oct. ZeroDegree Commissioning
Oct.-Nov.
MT for approved experiments at the first PAC
2008
Prototype of new linac injector
coupled with 28GHz ECR is being installed.
Increase of U intensity and decouple bet. SHE and BigRIPS

24. SUMMARY
PAC Feb 2007
19 proposals at BigRIPS/ZD, 74 % International Collaboration
Commissioning of Accelerator System and BigRIPS is
going smoothly step by step
Discovery of new isotope 125Pd
Experiments will start in this Oct.-Nov at BigRIPS/ZD.
Next PAC this Sep.
You are welcome
Come to RIKEN and see what is going on.