N. Saito The RISING stopped beam physics meeting Technical status of RISING at GSI N. Saito - GSI...

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N. Saito The RISING stopped beam physics meeting Technical status of RISING at GSI N. Saito - GSI for the RISING collaboration • Introduction Detector performance First results of RISING Coming experiments Outline

Transcript of N. Saito The RISING stopped beam physics meeting Technical status of RISING at GSI N. Saito - GSI...

N. Saito The RISING stopped beam physics meeting

Technical status of RISING at GSI

N. Saito - GSIfor the RISING collaboration

• Introduction• Detector performance• First results of RISING• Coming experiments

Outline

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Fragment Separator (FRS)

RISING with fast beams

Rare isotope beam + Target

In-beam - spectroscopy

Reaction target ~ 0.5 g/cm2

: ~ 100 MeV/u > 1000 pps

Ge-array

Beam

production target

Degrader

400 – 1000 MeV/u

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

• Secondary fragmentation – With a Be target – Weak inelastic excitation – Population of higher spin

states

• Coulomb excitation – With a Au target – Inelastic excitation

enhanced– One step excitation – Low spin – Excitation to high energy

Type of experiments

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Atomic Background Radiation

Atomic background cross section

To measure - rayabove ~ 400 keV

Beam energy ~ 100 MeV/u

X-rays from target atoms

Radiative electron capture (REC)

Primary Bremsstrahlung (PB)

Secondary Bremsstrahlung (SB)

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

FRagment Separator (FRS)

Dipole magnets : B selection

~ 100 MeV/u

400~1000 MeV/u

MUSIC : Z measurementMulti-wire chambers : Tracking

Fast plastic scintillator : Time of Flight (TOF)

AQ

Be c u

=

Degrader : E

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Identification of beam

Primary beam : 86Kr at 419 MeV/u Fragment setting : 56Cr

CATE

56Cr

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Identification of outgoing particle

CATE-Si • position sensitive• 0.3 mm thick Si • E measurement

CATE-CsI• CsI + PIN diode • Stop beams• E measurement

55Ni + 9Be

108Sn + 197Au

Two-step fragmentation

Coulomb excitation

CAlorimeter TElescope array

ECsI

ESi

ESi

E CsI

Si

CsI 5cm

5cm

E vs E ZZ

E + E AA

Z ~ 0.7

A < 1

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

p

MW MW CATE

Si CsITarget

x

y

Beam spot reconstruction on the target

x

y

Outgoing particle distribution on CATE

Tracking of incoming & outgoing particles

CATE-Si pos. res. ~ 5 mmopening angle ± 3°

MW pos. res. ~ 1 mm

Event-by-event Doppler correction

Impact parameters

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

RISING Ge-array

• 15 EUROBALL cluster detectors

• Clusters at forward angle• Large Lorentz boost (~0.4) • Optimum Doppler shift correction • Minimizing Doppler broadening

• Ring1 at 15.9° 70 cm• Ring2 at 33.0° 70 - 140 cm• Ring3 at 36.0° 70 - 140 cm

• Design (100MeV/u,1.3MeV -ray )• Option 1 : high resolution

• E = 1.0 % (FWHM)• = 1.5 %

• Option 2 : closest geometry• E = 1.6 % (FWHM)• = 2.8 %

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

RISING detectors

Target : Au or Be

15 EUROBALL cluster Ge detectors

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

RISING detectors

• HECTOR array : 8 BaF2 detectors. • For GDR experiments. • Time resolution : ~1 ns. • Background study.

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

RISING detectors

CATE

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Data acquisition system

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

First accepted proposalsNo. Nuclei of Interest Primary Beam Spokespersons Experiment Type Accepted

Request (days)

1(S244)

34/36Mg 48Ca P. Mayet2 step fragmentation

lifetime6

245Cr,53Ni,45Sc,

53Mn58Ni M. Bentley 2 step fragmentation 7

3 68Ni 86Kr A. Bracco GDR 7

454Ca, 78Ni ,56Cr 86Kr

H. Grawe,H. Hübel, P.Reiter 

Coulex 13

5 88Kr, 90Sr, 86Se 238U D. Tonev Coulex 10

6 102-110Sn, 94-98Ru

124Xe C. Fahlander,M. Górska

Coulex 6

7 132Sn 238U G. de Angelis Knock-out 5

8 132Xe 136Xe A. MajCoulex, Angular

Distr. / Correlations3

9 134Te 136Xe K.-H. Speidel Coulex, g-factor 7

10185,186,187Pb 238U

J. Gerl,A. Andreyev

G.D. Dracoulis

2 step fragmentationlifetime

8

84Kr 84Kr Coulex, Ang. Corr. ~ 78’

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Coulomb excitation of stable 84Kr

84Kr at 113 MeV/u on a 0.4 g/cm2 Au

Conditions for the analysis :• Particle Identification before and after the target• Scattering angle selection 84Kr : 0.5 ~ 2.5 degrees• Selection of one-step Coulomb excitation <M>=1• 84Kr : = 0.396 ( from TOF measurement)

Without D.c. With D.c.

84Kr 2+ 0+

FWHM ~ 1.5 %

Energy [keV] Energy [keV]

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Coulex of radioactive beams

86Kr 419 MeV/u → 56Cr 136 MeV/u on Au 1.0 g/cm2

Preliminary

56Cr 2+->0+

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Two-step fragmentation58Ni 600 MeV/u → 55Ni 171 MeV/u on Be 0.7 g/cm2

NiCoFeMnCr

CaTi

ArS

Si

CATE ECsI

CATEdESi

Preliminary

2+ -> 0+

4+ -> 2+

6+ -> 4+

(8+ -> 6+)

50Cr

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Schedule 2004

May : Two experiments at relativistic energies with HECTOR GDR in 68Ni (A. Bracco) Shell structure at N>>Z nuclei (H. Grawe, H. Hübel, P. Reiter)

Nov/Dec : Experiments at relativistic energies with MINIBALL

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

MINIBALL

Angle 51.3° 86°

Detectors 5 3

Distance 400 mm 400 mm

E 0.36 % 0.37 %

0.82 % 0.36 %

Array E

Clusters 1.0 % 1.5 %

Clusters (70cm) 1.6 % 2.8 %

MINIBALL 0.36 % 1.2%

Total 1.2 % 4.0 %

max = 7.4 % (MINIBALL at ~20cm)

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

2004 May : Experiments at relativistic energies with HECTOR Nov/Dec : Experiments at relativistic energies with MINIBALL

2005 - April : Experiments at relativistic energies with MINIBALL Autumn : Experiments with stopped beams

- -isomer decay - - and -decay- Lifetime measurements in ps~ns with electrical timing methods

2006 Experiments with relativistic beams and stopped beams Feasibility studies for experiments with slowed-down beams

- Multiple Coulomb excitation- One- and two-particle transfer reactions- Fusion and deep inelastic reactions

Schedule

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Two-step fragmentation58Ni 600 MeV/u → 55Ni 171 MeV/u on Be 0.7 g/cm2

NiCoFeMnCr

CaTi

ArS

Si

CATE ECsI

CATEdESi

52Fe 2+ -> 0+

52Fe 4+ -> 2+

Preliminary

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

RISING Ge-array

• 15 EUROBALL cluster detectors • Clusters at forward angle

• Large Lorentz boost (~0.4) • Optimum Doppler shift correction • Minimizing Doppler broadening

•Ring1 at 15.9° 70 cm•Ring2 at 33.0° 70 - 140 cm•Ring3 at 36.0° 70 - 140 cm

•Performances for different distances• Design

• E = 1.0 % (FWHM)• = 1.5 %

• Option : closest geometry• E = 1.6 % (FWHM)• = 2.8 %

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

FRagment Separator (FRS)

Dipole magnets : B selection

Fast plastic scintillator : Time of Flight (TOF)

~ 100 MeV/u

400~1000 MeV/u

MUSIC : Z

Multi-wire chambers : Tracking

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Relativistic Coulomb excitation with the 84Kr primary beam

Scattering angle dependence

2.0-2.5

0.5-1.0

1.5-2.0 2.5-3.0

1.0-1.50.0-0.5

Preliminary

Mainly elastic scattering

Nuclear reactionCoulomb excitationAnalysis by T.Saito

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Two-step fragmentation

Analysis by T.Saito

58Ni 700 MeV/u → 55Ni 171 MeV/u on Be 0.7 g/cm2

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

Two-step fragmentation58Ni 600 MeV/u → 55Ni 171 MeV/u on Be 0.7 g/cm2

NiCoFeMnCr

CaTi

ArS

Si

CATE ECsI

CATEdESi

Preliminary

54Ni 2+ -> 0+

54Ni 4+ -> 2+

29 Mar. 2004N. Saito The RISING stopped beam physics meeting

FRagment Separator

Dipole magnets : B selection

Fast plastic scintillator : Time-Of-Flight (TOF)

Multiwire chambers : TrackingMUSIC : Z measurement

~ 100 MeV/u

~ 1 GeV/u