RITU and the new separator at Jyvskyl

J. Uusitalo, J. Sarn, M. LeinoRITU and -groupsUniversity of Jyvskyl, Department of Physics

Magnetic configuration QvDQhQvMaximum beam rigidity 2.2Tm Bending radius 1.85 m Angular acceptance 8 msr - measured with alpha source Dispersion 10 mm/% of B Dipole bending angle 25o- Total length 4.8 mRITU, Recoil Ion Transport Unit

40Ar + 175Lu >211Ac + 4nEfr = 33 MeVqave = 6.9vert. acc. 26 mradhoriz. acc. 77 mradAcceptance 8 msr

JUROGAMRITUGREAT

Nuclear Physics Group at Daresbury, University of Liverpool, Manchester University, University of Surrey, York University,Keele University

MWPCPIN-diodesDSSSDPlanar GeClover GeTDR acquisition system

The GREAT detector system2x 60mm x 40mm DSSD28x 40mm x 40mm PINSegmented planar GeCompton-suppressed Ge cloverGas counters

U.K. Universities & DaresburyTriggerless TDR DAQ systemPresently at JYFL

NIMB 204, 138 (2003)T. Enqvist et.al.,

112Sn(86Kr, 3n)195Rn @ 365 MeV

0, 26 mrad, 0, 1mm

Dispersion 15 mm/%BA gas-filled recoil separator plan

if B difference 4 % between195Rn and beam 86Kr, and 7 mrad for beam and 26 mrad for 195RnRITU QDQQ with 25o dipole magnet DQQ with 50o dipole magnet DQQ with 50o dipole magnet, and Bn = -4

The new JYFL vacuum mode separatorDesign, ion optics and PhysicsMatti Leino, Jan Sarn, Juha Uusitalo,RITU and GAMMA groups

Magnetic rigidity:

Electric rigidity:Resolving power:

Deflection angles in electric field:

Universal:

- Both electric and dipole fields are needed - Beam is dumped inside the first dipole (chamber)- Mass resolving power about 350 FWHM can be reached- Full energy beam suppression factor of 109-1015 can be expected

Charged particle in electric and magnetic fields

DRS:Q1-Q2-Q3-WF1-WF2-Q4-Q5-Q6-S1-S2-MD1-Q7-Q8-Q9 (13.0 m)CARP: Q1-MD1-H1-H2-ED1-H3-Q2CAMEL: Q1-Q2-ED1-S1-MD1-S2-ED2HIRA: Q1-Q2-ED1-M1-MD1-ED2-Q3-Q4(8.6 m) JAERI-RMS:Q1-Q2-ED1-MD1-ED2-Q3-Q4-O1(9.4 m)FMA: Q1-Q2-ED1-MD1-ED2-Q3-Q4(8.2 m)EMMA:Q1-Q2-ED1-MD1-ED2-Q3-Q4(9.04 m)JYFL new:Q1-Q2-Q3-ED1-MD1 (6.74 m)

QquadrupoleSsextupoleHhexapoleMmultipoleOoctupoleWFvelocity filterEDelectric dipoleMDmagnetic dipoleMass separators all around the world: some trends

- Maximizing angular, mass and energy acceptance while minimizing geometric and chromatic aberrations.

- The largest aberrations are (x|2), (x|) and (x|2). These are minimized by adding a curvature to the magnetic dipole entrance and exit.

- Higher order aberrations found to be negligible.Design principles and aberrations

Optical layout in floor coordinates

Angular focus in x- and y-directionsX-direction, 5 angles: 0, 15 and 30 mradY-direction, 5 angles: 0, 20 and 40 mrad

Energy focus and mass dispersion in x-directionEnergy deviation: 0, 3.5 and 7.0 %Angles: 0 and 30 mrad,Masses: 0 and 1 %Energies: 0 and 7.0 % 3 different energies 3 different angles 3 different masses

FMAJYFL new

- ConfigurationQQEDMDEDQQQQQEDMD- Horizontal magnification -1.93-1.58- Vertical magnification 0.98-4.48- M/Q dispersion -10.0 mm/%8.1 mm/%- First order resolving power, 259256 2 mm beam spot Solid angle acceptance 8 msr10 msr- Energy acceptance for central mass and angle +20 % - 15 %+20 % - 15 %- M/Q acceptance 4 % 7 %

Main properties of the new separator compared to FMA

What kind of research work can be done were RITU separator is not feasible

Probing the N Z line up to 112Ba- decay spectroscopy (proton and -particle decay) at the 100Sn region- rp-process- proton-neutron pairing interaction- mirror nucleio study of isospin symmetry breakingo proton skins (N < Z nuclei) D. Joss- superdeformation and hyperdeformation (N Z 40)

Methods- focal plane detector system:o DSSSD, position sensitive gas counter (1 mm granularity)- Trackingo Ge-detectors- MWPC & ICo Z- identification - tape system- focal plane spectroscopy - , proton, , , -delayed protons and alphas - prompt and delayed coincidences - in-beam spectroscopy tagging with using focal plane measurables

Phase space correction

Mass separation at focal plane

X-deviations versus TOF can be seen in phase space corrected data -> time correction can be made to improve x-resolution

Simulation of electric field in deflector (code Poisson Superfish) gap 14 cm rounded edges splitted anode maximum voltage between plates is about 0.5 MV

Simulating particle trajectories in deflector fieldSimple modified Euler equation is used to trace particles in electric field.Real transfer matrix coefficients can be obtained from these simulations. This more realistic matrix can be used in optical simulations of the new separator.100 MeV, 100 u, 26 e200 MeV, 50 u, 21 e92Mo: 362 MeV, 92 u, 32 e147Tm: 222 MeV, 147 u, 37 e

JIono ionoptical simulations, Jan Sarn Features (some are not implemented yet): both graphical and text interfaces uses GICO/GIOS transfer matrices adjustable aperture slits export/import data real particle parameters as input data (m, E, q) Multiple types of plots Windows and Linux