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RITU MARA Summary
RITU AND MARA: A complementary couple
Cath Scholey
Department of PhysicsUniversity of Jyvskyl
Arctic FIDIPRO-EFES Workshop20th-24th April 2009
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 1 / 14
RITU MARA Summary
Layout
1 RITUIntroductionPhysics Programme @ RITUThe 100Sn Region
2 MARASeparator DesignCurrent StatusPhysics GoalsA≈100 Example
3 Summary
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 2 / 14
RITU MARA Summary
RITU - Recoil Ion Transport Unit (est. 1993)
Magnet configuration: QDQQ
He-gas filled ∼0.7mbarTransmission:Very symmetric ≈ 60 %,e.g 84Kr + 90ZrVery asymmetric ≈ 10 %,e.g 22Ne+238U
Efficient, very little massresolving power.
Ancillaries:At present: JuroGam II,GREAT and Köln plungerIn the future: JuroGam X,SAGE, LISA, JYFLplunger and GREAT
26 New isotopes: 210,211Th, 206−208Ac, 201−204Ra, 198,200Fr, 195,197Rn, 190−195At, 189Po, 176Tl,171,174Hg, 164Ir, 161Os,159Re, 157W.
>50 First excited states: Lightest 78Y, Heaviest 255Lr, most neutron deficient 180Pb.
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 3 / 14
RITU MARA Summary
RITUs Nuclear Landscape
Spectroscopy above 100Sn
Transitional Proton Dripline Nuclei
The Heavy ElementsShape Coexistance in the Pb region
SP States +Proton Decay above Pb
N-rich NucleiTransfer reactions
Mass 60-70N~Z, CEDin IAS Isomer studies
Mass 130-150X5 symmetries?
Octupole CollectivitySpectroscopy of Trans-U Nuclei
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 4 / 14
RITU MARA Summary
Enhanced Collectivity above Sn
JYFL studiesRecoil decaying taggingmeasurements - fast alphaor proton decay to selectthe γ-rays of interest.
54Fe(54Fe,2n)106Teσ ≈ 25 nbHadinia et al., PRC 72041303(R) (2005)58Fe(52Cr,3n)107TeHadinia et al., PRC 70064314 (2004)58Ni(54Fe,p2n)109Iσ ≈ 10µbPetri et al., PRC 76054301 (2007)58Ni(54Fe,2n)110Xeσ ≈ 50 nbSandzelius et al., PRL 99022501 (2007)
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 5 / 14
RITU MARA Summary
Life-time Measurements
Life-time measurements of 109I - 2 weeks last December - D.M. Cullen. VeryPreliminary results of states in 109Sb. Also produced 108,109Te 106,108Sn and hopefully109I.
band 2
μ
μ
μ
μ
ENERGY (keV)
CO
UN
TS / 0
.5ke
V
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 6 / 14
RITU MARA Summary
Life-time Measurements
Life-time measurements of 109I - 2 weeks last December - D.M. Cullen. VeryPreliminary results of states in 109Sb. Also produced 108,109Te 106,108Sn and hopefully109I.
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 6 / 14
RITU MARA Summary
Enhanced Collectivity above Sn - The next steps
In-beamExcited states in 108I - Scholey, Uusitalo
B(E2) Measurements of the 2+ and 4+ statesin 108,110,112Te - Cederwall and Wadsworth.
Using β-delayed α and proton emission as aselective tag for RDT.
Decay SpectroscopyAccepted proposal: Search 108Xe and theproton decay of 108I
Submitted proposal: Search for 113Ba.
In the near future 112Ba.
Total fusion cross sections
RITU MARA Summary
MARA- Mass Analysing Recoil Apparatus (est. 201X)
Juha Uusitalo – DesignerJan Sarén - Simulator
Point to point focus in Y point to || for deflector
Fixed energyfocus gives m/q
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 8 / 14
RITU MARA Summary
MARA- Mass Analysing Recoil Apparatus (est. 201X)
MARA Specifications - Mass resolving power 1/250Ion optical configuration Q1Q2Q3DEDMLength from target to the focal plane 6.7 m(reference particle)Angular acceptance 8 msr (±45 mrad in x
and ±55 mrad in y)Electric rigidity acceptance for approximately ± 15%central trajectory (depends on magnetic dipole chamber)Dispersion 8 mm/(% of m/q)Q1 effective length 250 mmQ1 aperture diameter 100 mmQ1 maximum field gradient 10.0 T/mQ2,3 effective length 350 mmQ2,3 aperture diameter 150 mmQ2,3 maximum field gradient 10.0 T/mElectric dipole pending angle and radius φ = 20◦ and ρ = 4.00 mElectric dipole gap 140 mmMagnetic dipole pending angle and radius φ = 40◦ and ρ = 1.00 mMagnetic dipole gap 100 mm
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 8 / 14
RITU MARA Summary
MARA - Current Status
3 quadrupoles, 2 power supplies, 1 magnetic dipole, simulations are in progress. One electrostatic deflectoris missing!
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 9 / 14
RITU MARA Summary
MARA - Current Status
RITU MARA
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 9 / 14
RITU MARA Summary
MARA - Physics Goals
Decay spectroscopy (proton and α-particle decay) around 100Sn.112Ba→108Xe→104Te→100SnProton drip-line spectroscopyCompetition between proton and γ-rays.new proton emitters
rp-processmasses half-lives and isomers in N=Z nuclei determine the rp- processsynthesis rate.
Proton-neutron pairing interaction with T = 0 and T = 1Mirror nuclei
Effects of increasing Coulomb field -CED in IASStudy of isospin symmetry breakingProton skins (N < Z nuclei)
Super-deformation and hyper-deformation (N≈Z ≈40)In reality, the users decide and ideas are welcome, as is funding!
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 10 / 14
RITU MARA Summary
Focal plane
Focal plane detector system: slit system 10cm up-stream and down-stream of thefocal plane. At the focal plane - MWPC (1 mm granularity), 40cm down-streamDSSDs
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 11 / 14
RITU MARA Summary
108Xe - a worked exampleCross-sections (PACE4)
EVAPORATION - Compound nucleus 112Xe; Mode 1Excitation energy 59.2 MeV
Compound nucleus formation cross section: 6.44e+02 mb
L I S E ++ [Noname]18-04-2009 13:25:24
49.5 50.5 51.5 52.5 53.5 54.5 55.5 56.5 57.5 58.5Neutrons (N)
45
47
49
51
53
55
Pro
ton
s (Z
)
5e-031e-022e-023e-026e-021e-012e-014e-018e-011e+003e+005e+009e+002e+013e+016e+011e+02
54Fe(58Ni,4n)108Xe @240MeV target thickness 0.5µg/cm2 beam energy calculated by Korgul et al, PRC 77 034301 (2008)
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 12 / 14
RITU MARA Summary
108Xe - a worked example
Still to doTOF flight Hopefully gives backreduction of 2
Spherical Aperture before the 1st
QuadrupoleCut 108Xe by 7%, but others by 30%,purely recoil cone dependent.
Charged particle detection @ targetposition.
Include horizontal angle correctionwith position sensitive detectors.
half-lives of exotic nuclei are usuallyon our side. Factor of 106.
REMEMBER we can run slower andlonger as more beamtime is availablethanks to the new cyclotron.
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 12 / 14
RITU MARA Summary
Summary
RITU - Is a very efficient and versatile separator.
Produced new isotopes from W to Th (hope to produce more, bothheavier and lighter)
Excited states ranging from Y to Lr
MARA - will be a very selective device
Complement and continue to the successes of RITU and with MARA
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 13 / 14
RITU MARA Summary
Thanks
Thanks to the RITU-γ team.
Thanks to all those who have performed experiments at JYFL and thosewho are planning to.
Thanks to Juha Uusitalo and Jan Sarén for their work on MARA.
Thanks to you for listening.
Cath Scholey (JYFL, Finland) RITU AND MARA: A complementary couple April 21st , 2009 14 / 14
RITUIntroductionPhysics Programme @ RITU The 100Sn Region
MARASeparator DesignCurrent StatusPhysics GoalsA100 Example
Summary
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