N. Saito The RISING stopped beam physics meeting Technical status of RISING at GSI N. Saito - GSI for the RISING collaboration Introduction Detector performance.

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


• 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


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)


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


Identification of beam

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

CATE

56Cr


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


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


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 %


RISING detectors

Target : Au or Be

15 EUROBALL cluster Ge detectors


RISING detectors

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


RISING detectors

CATE


Data acquisition system


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’


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]


Coulex of radioactive beams

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

Preliminary

56Cr 2+->0+


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


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


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)


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





NiCoFeMnCr

CaTi

ArS

Si

CATE ECsI

CATEdESi

52Fe 2+ -> 0+

52Fe 4+ -> 2+

Preliminary


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 %


FRagment Separator (FRS)


Fast plastic scintillator : Time of Flight (TOF)

~ 100 MeV/u

400~1000 MeV/u

MUSIC : Z

Multi-wire chambers : Tracking


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


Two-step fragmentation

Analysis by T.Saito

58Ni 700 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+


FRagment Separator


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

Multiwire chambers : TrackingMUSIC : Z measurement

~ 100 MeV/u

~ 1 GeV/u

N. Saito The RISING stopped beam physics meeting Technical status of RISING at GSI N. Saito - GSI for the RISING collaboration Introduction Detector performance.

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