RI Beam Factory Project at RIKEN

H.SakuraiRIKEN Nishina Center for Accelerator-based Science

http://www.nishina.riken.jp/

1. Overview of RIBF facility and physics with exotic nuclei

2. Introduction of Phase-I facility and Experimental programs

3. Recent achievements and future plan4. Summary

RIPSGARIS

~100 MeV/u

CRIB (CNS) BigRIPS/ZeroDegree

~5 MeV/u

350-400 MeV/nucleon

Existing facility

New facility 350 MeV/nucleon up to U

1st beam in 2006

Phase–I 2007-SRC + BigRIPS/ZeroDegree440 M$ (1$=100JPY)

Phase-IIExperimental Installations2007~2010 (plan)

RIBF Facility Layout

SRC

RILAC

AVF

RRCfRC

IRC

SHE

~10 MeV/u

- towards the drip-lines -

Fission 238U 350A MeV

neutron-rich side 20<Z<60

wide dynamic range

Projectile fragmentation 48Ca, 58Ni, 78Ge, 78Kr, 112Sn, 204, 208Pb, 238U, ... 350~400A MeV proton-rich side neutron-rich A<50 or A>160

SRC high energy and intense heavy ion beams upto U 350 – 400 A MeV Goal of intensity 1 p-micro ABigRIPS high acceptance for fission fragments

limit of production 1 particle/day

Exploration of the limits of nuclear existence

3rd generation of RI beam facility “Fission fragment of U”

78Ni ~10 particles/sec goal

SAMURAI - large acceptance Kobayashi et al.

SHARAQ - high resolution Shimoura et al.

Rare RI Ring – mass　　 Ozawa et al.

SCRIT - e-RI collision Wakasugi, Suda et al.

SLOWRI- slow beams Wada et al.

Phase-II construction 2007-2010To maximize the potentials of intense RIBs available at RIBF

RI Spin Lab. at RIPS –pol. RI beam Ueno et al.

http://rarfaxp.riken.go.jp/RIBF-TAC05/

in 2008

60 M$

About 2M $ was approved in FY2007 for the infrastructure, radiation shields, ZeroDegree electronics.

by Narumasa Miyauchi

Acceleration Flow in RI Beam Production

RILAC

RRC

fRC

IRC

SRC

BigRIPS

ZDS

6

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

BigRIPS /ZeroDegree

operated by Kubo group

Exploration into “Isospin Frontier” toward the drip-linesReaction study fit for high energy domain 200-300A MeV

RIB productionPID section

PID section

Configuration Two-stage separator First stage Two bends Second stage Four bendsEnergy degrader Achromatic wedgeQuadrupoles SuperconductingAngular acceptance Horizontal 80 mr Vertical 100 mrMomentum acceptance 6 %Max. magnetic rigidity 9 TmTotal length 77 mMomentum dispersion* First stage -2.31 m Second stage 3.3 mMomentum resolution**(1st order) First stage 1290 Second stage*** 3300

Basic parameters of BigRIPS

* At the mid-focus of the stage. ** Those in the case when a 1 mm beam spot is assumed.

In-flight fission of 2

38U at 350 MeV/u~ 100 mr~ 10 %

T. Kubo et al.

Specifications of optical modes(I) Achromatic: Large acceptance mode

Maximum magnetic rigidity = 7.3 TmAngular acceptance Horizontal = +/-45 mrad, Vertical = +/-30 mardMomentum acceptance = +/-3 %Momentum dispersion = 2.24 cm/%Momentum resolution = (X,P)/(X,X) =1240

(II) Achromatic: High resolution modeMaximum magnetic rigidity = 9.0 TmAngular acceptance Horizontal = +/-20 mrad, Vertical = +/-30 mardMomentum acceptance = +/-3 %Momentum dispersion = 2.12 cm/%Momentum resolution = (X,P)/(X,X) = 2120

(III) Dispersive spectrometer modeMaximum magnetic rigidity = 9.0 TmAngular acceptance Horizontal = +/-20 mrad, Vertical = +/-30 mardMomentum acceptance = +/-2 %Momentum dispersion = 4.13 cm/%Momentum resolution = (X,P)/(X,X) = 4130

(IV) Transmission mode

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, Q, R, 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 beamsCollectivity 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....

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 regionsSpecific programs with deuteron beams

RIBF layout

in 2007-2008(Phase-I layout)

Experimental set-ups

ZDS: Zero-Degree forward Spectrometer

-spectroscopy

in-beam gamma spectroscopymissing mass spectroscopy

total reaction cross sections

(d,3He) Pol.d+p

ZeroDegree Spectrometer

http://www.nishina.riken.jp/UsersGuide/BigRIPS/intensity.html

RI beam intensities at BigRIPS for first two years 2007-2008

Primary beam energy 350AMeV48Ca (200pnA), 86Kr (100pnA),136Xe (10pnA), 238U(2pnA)

Secondary beam energy ~250A MeVCross sections Fragmentation EPAX-II

Fission GSI-data (U+Be), ABRABLA (Coulomb)

CollaborationOne of the largest heavy-ion facilities in the Asia/world

Open for the world-wide user community

International Collaboration Workshop on Experiments at the RIBF6th-9th November 2006 ~130 participants; ~30 from foreign institutes/universities

Presentation and discussion of experimental projects to be done in collaborationTo identify common interestsTo have “show case” for experimental technique, methods, detectors …To establish collaborationsTo prepare proposals

MOU“Creation of the council for China-Japan Research Collaboration on Nuclear Physics”10th November 2006

19 proposals submitted to PAC Feb.2007 (74% international)

France-Japan collaboration will be established soon

Recent achievements / Future plan

28th Dec. 2006First Beam 27Al10+ at RIBF-SRC

Mar. 200712th 86Kr31+ beam at 345 A MeV several pnA.13th First Production of RIBs at BigRIPS23rd First successful acceleration of 238U beam 0.002pnA27th First production of radioactive isotope beams via a U beam

Last week 238U beam 0.02pnA max BigRIPS Commissioning; New isotope 125Pd

Recent achievements

First beam accelerated at SRC K2600MeV

16:00 28th Dec., 2006 27A ｌ 10+ 345MeV/u

N=Z

N=Z+1

N=Z+2

N=Z+3

Sc

Ca

TiV

CrMn

Fe

Co

NiCu

Zn

K

Ar Cl

S P

SiAl

43Sc

54Fe

First RIB

13th Mar. 200786Kr + Be(2mm) at 345 MeV/u

E

TOF (F3-F7) Kubo et al.

PID for isotopes created via a 345 A MeV U beams w/o degrader

TOF(F3-F7) [ns]

E@

F7 [

MeV

]

Nb

Y

Tc

Rh (Z=45)

Ag

In

Sb

IXe

RbBr (Z=35)

AsGa

CuCo

Zr (Z=40)

Mo

Ru

Pd

Cd

Sn (Z=50)

Te

Sr

KrSe

Ge

Zn (Z=30)

Ni

Fe

98Y

132Sn

104Zr

117Rh

91Br

76Zn70Ni

82Ge

Mar. 27th, 2007

T. Kubo et al.

A/Q

Z

Z

A/Q

Z=46

Bρ: 7.438 TmTarget: Be 7mm

Total dose: ~1×1013

Total time: 25.4 hours

238U86+ 345 MeV/u～ 1enA on Target

The first test experiment at RIBF

M.Bernas et a. PLB 331(94)19; PLB 415(97) 111

122Pd

123Pd124Pd

125Pd

122Pd45+

121Pd45+

120Pd45+

119Pd45+

123Pd45+

A/Q

Co

unt

s

122Pd 2.6521(2.6506) 38 counts

123Pd 2.6739(2.6728) 245 counts

124Pd 2.6956(2.6952) 173 counts

125Pd 2.7174(2.7171) 59 counts

122Pd45+ 2.7111(2.708) 16 counts

121Pd45+ 2.6888(2.6871) 55 counts

120Pd45+ 2.6666(2.6648) 41 counts

119Pd45+ 2.6444(2.6413)

123Pd45+ 2.7333(2.7321) 15 counts126Pd?

A/Q resolution(r.m.s): 0.07% At Z=40

Discovery of 125Pd

Cf. 124Pd 19 counts, 125Pd(cand.) 1count at GSI, 1997 PLB 415, 111 (97) total dose ~1x108

Setup for May-2007 Commissioning

Prod. Target Be 7mmtBeam-intensity monitor PL 1mmt x 3

Double AchromaticPL 0.2mmtPPAC(x,y) x2

Momentum DispersivePPAC(x,y) x2

Double AchromaticPL 0.2mmtPPAC(x,y) x2Silicon 0.33 mmt x2 for ENaI for EClover for isomeric states

Setup to search for new isotopes

B

TOF

Mom. SlitDp/p=2%(Max 6%)W/o Wedge

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.SakuraiOECU, Osaka Y. MizoiRikkyo Univ. M. MatsushitaUniv. of Tokyo H. Suzuki, T. Nakao, H. KimuraSaitama Univ. T. Kuboki, T. YamaguchiTsukuba Univ. A. Ozawa, T. Moriguchi, Y. YasudaTokyo Inst. Tech. T. Nakamura, T. Nannichi, T. Shimamura, Y. Nakayama

GSI H. Geissel, H. WeickANL J. NolenNSCL/MSU O.Tarasov, T. Nettleton, D. Bazin, B. Sherrill, D. MorrisseyGANIL W.Mittig

Collaborators

200718th 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

2008Prototype of new linac injector coupled with 28GHz ECR is being installed. Increase of U intensity and decouple bet. SHE and BigRIPS

Future plan

SUMMARY

PAC Feb 200719 proposals at BigRIPS/ZD, 74 % International Collaboration

Commissioning of Accelerator System and BigRIPS is going smoothly step by stepDiscovery of new isotope 125Pd

Experiments will start in this Oct.-Nov at BigRIPS/ZD.

Next PAC this Sep. http://www.nishina.riken.jp/UsersGuide

You are welcome Come to RIKEN and see what is going on.

http://www.nishina.riken.jp/