Zoran Andjelkovic Johannes Gutenberg – Mainz University GSI Darmstadt Laser Spectroscopy of Highly Charged Ions and Exotic Radioactive Nuclei (Helmholtz Young Investigator Group) SPECTRAP meeting status report

Zoran Anđelković 2 A short progress overview Introduction: –HITRAP overview –magnet & trap Beamline & detectors: –transporting the ions –deceleration –necessary modifications Current status and measurements: –candidates –status –time plan

Zoran Anđelković 3 Overview of the HITRAP Facility UNILAC SIS 400 MeV/u ESR U 92+ Pb 81+ Bi 80,82+ 4 MeV/u Electron cooling and deceleration Stripper target Post decelerator Cooler trap Experiments with particles at rest HITRAP SPECTRAP trapping of HCI cooling nearly to rest laser spectroscopy of HFS

Zoran Anđelković 4 system overview + ions from: sputter gun (Ar) oven (Mg) EBIT (mid Z) HITRAP (high Z)

Zoran Anđelković 5 trap overview

Zoran Anđelković 6 added mirrors and lenses increased fluorescence rate (solid angle) low wavelengths not reachable

Zoran Anđelković 7 beam transport simulations by Shailen Bharadia beam waist measurements with a 4-jaw slit slight deformation after bending good trasport efficiency, injection into the B field

Zoran Anđelković 8 decelerating ions two stage deceleration deceleration efficiency of some 90% (energy not sharp) simulations: inside B field even better

0 V V V 0 V V -990 V 2,5 keV 10 eV SIMION simulations by Dirk Tiedemann

Zoran Anđelković 10detectors Destructive: MCP in-line Channeltron for off-axis detection Non-destructive: Resonant detection inside the trap Arrival detector endcap C R L detect excite from an endcap

Zoran Anđelković 11 current layout + extensions new He recovery line an extension needed to be mounted: MCP to be mounted: channeltron + a small platform extension

Zoran Anđelković 12 hyperfine transition measurements TypeIonTransition [nm] A [1/s] H-like 165 Ho 66+ F=3 – F= Re 74+ F=2 – F= Re 74+ F=2 – F= Tl 80+ F=0 – F= Tl 80+ F=0 – F= Pb 81+ F=0 – F= Bi 82+ F=4 – F= U 91+ F=3 – F= Li-like 209 Bi 80+ F=4 – F=

Zoran Anđelković 13 or fine transitions im mid Z GroupIonConf.Transition [nm] A [1/s] IIIA (16)S 11+ 2s 2 2p 2 P 1/2 - 2 P 3/ (18)Ar 13+ 2s 2 2p (26)Fe 13+ 3s 2 3p (27)Co 14+ 3s 2 3p IVA (20)Ca 14+ 2s 2 2p 2 3P0-3P13P0-3P (21)Sc 15+ 2s 2 2p (22)Ti 16+ 2s 2 2p (23)V 17+ 2s 2 2p (33)As 19+ 3s 2 3p

Zoran Anđelković 14 or just to have a slow start... trapping Ar 2+ –readily available in large quantities –spectroscopy difficult if not impossible trapping and laser cooling of Mg + –easy to trap, laser available –a bit problematic to produce combination of the two Pb + –strong interest in the results –very difficult to produce –difficult to trap

Zoran Anđelković 15 the resonant frequencies

Zoran Anđelković 16 Current status We have: platform with infrastructure assembled beamline experimental control electronics (LabVIEW oriented) cryo-electronics almost ready We want: an ion source electronics, detectors... Next steps: connect the cryo-electronics and wire the trap prepare an ion source (sputter gun, oven, EBIT?) cool down the magnet and the fun starts...

Zoran Anđelković 17 and now for something completely different... month: Cryo-electronics done x Modify the platform, beamline xx Trap instalation and wiring xx Trapping, testing, practicing xxx Cooling down xxxx Initial experiments xx... Zoran – hopefully no lab work xx TIME PLAN!