Institut für Physik Ernst-Moritz-Arndt-Universität Greifswald, Germany or just find me on facebook

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1 Gerrit H. Marx stitut für Physik nst-ritz-arndt-niversität Greifswald, Germany or just find me on facebook 6th stes of Nuclear Physics,

2 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

3 Objective: to store and investigate particles in free space light reactions and decay products ser RF charged particles atoms

4 hy, in particular? To make use of extended preparations extended interactions extended reaction periods multi-step sequences

5 Trapping is a serious business S. van der Meer C. bbia Nobel ize 1984 "for their decisive contributions to the large project, which led to the discovery of the field particles and Z [ ]" S. Chu C. Cohen-nnoudji. D. Phillips Nobel ize 1997 "for development of methods to cool and trap atoms with laser light" H. Dehmelt. ul Nobel ize 1989 "for the development of the ion trap technique" E. Cornell. Ketterle C. ieman Nobel ize 1 "for the achievement of Bose-Einstein condensation [ ]"

6 Trapping is also FN Demo trap with single ion video

7 Demo traps with ion ensembles

8 Application of ion storage devices ATOMC PHSCS MOLECLAR & CLSTER PHSCS laser + microwave spectroscopy reactions, life-times PLASMA PHSCS ordered structures CHEMSTR NCLEAR PHSCS nuclear binding energies decay studies FNDAMENTAL TESTS METROLOG CPT, QED parity violation CVC kilogram fine structur constant frequency standards ON BEAM MANPLATON cooling beam-bunching accumulation new accelerator & decelerator concepts ultra-high mass separation

9 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

10 storing force Harmonic potential Cooling electric fields magnetic fields (light fields) harmonic oscillation or 3 independent eigen frequencies damping of oscillation amplitudes infinite storage time: Single electrons trapped for several months! (G. Gabrielse/Harvard)

11 w to trap ions? electrostatic trapping not possible due to Earnshaw static electric and magnetic fields Penning trap CR cell (ion cyclotron resonance) FT-CR MS, FTMS electric radiofrequency fields quadrupolar potential: ul trap, rf trap, QSTOR, ion trap

12 Alternative ion trapping techniques STORAGE RNG small! GS/Darmstadt

13 Future Facilities at GS SS 1/3 SS NESR beam One Example: Factor 1 more pbar trapped or stopped in gas targets than presently NLAC FRS HESR ESR Super FRS CR RESR 1 m BG! NESR

14 Alternative ion trapping techniques EBT Electron Beam on Trap (cf. EBS) LLNL, Livermore/CA replace place: = by isson: =

15 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

16 on storage devices Penning and ul Trap Storage Ring.5 1 cm particles at rest in space relativistic particles

17 Storage of charged particles wanted: if possible: potential minimum in 3 dimensions harmonic force in direction of trap center F ~ - r harmonic oscillations F = -e ~ - r Ax By Cz in addition: = (place equation) z simplification: rotational symmetry (z-axis) y x

18 Storage of charged particles in an ion trap d x y z z d equipotential surfaces: z = const hyperboloidal shapes geometry of ring electrode z end cap geometry of endcaps z z characteristic trap dimension d z z r minimum radius of ring electrode minimum distance between endcaps z ring electrode

19 Storage of charged particles in a Penning / ul trap BT: sign of different! r no simultaneous trapping in 3 dimensions possible by purely electrostatic potentials SOLTON: a: superposition of magnetic field in z-direction: Penning trap b: time varying voltage (RF) between ring electrode and endcaps: ul trap

20 potential ul trap geometries e linear RFQ trap RF 3D confinement ring electrode end cap

21 Buffer gas cooling in - and 3-dimensional ul traps D 3D RF

22 Equation of motion in a ul trap e r,t equation of motion: m r = e e r V cos m m V cos t t z = z = substitution: t u = x, y, z a q z a r 8e mr 4e V z qr V mr d d u a u q u cos u Mathieu differential equation

23 on motion in a ul trap Solution for small amplitudes: u( t) 1 q u cos t cos u t micro motion (fast, RF) macro motion (slow) on trajectory Stable motion only for special combinations of and V STABLT DAGRAM

24 Stability diagram of a ul trap V a Z

25 equency and Mass Distribution of Trapped Clusters equency Distribution frequency separation and width Mass Abundance Mass (amu)

26

27 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

28 inciple of Penning traps Cyclotron frequency: 1 f c q m B end cap PENNNG trap Strong homogeneous magnetic field eak electric 3D quadrupole field z r ring electrode ans Michel Penning (Penning discharge 1936) Hans G. Dehmelt (Nobel prize in physics 1989)

29 Confinement in a Penning trap axial harmonic potential radial confinement with magnetic field

30 Hyperbolical Penning trap Penning trap configurations Cylindrical Penning trap Axial tential main electrod correction ele mm 1 5 mm 1 1 mm main electrodes correction electrodes z (V) main electrodes correction electrodes 4 8 z (V)

31 Equation of motion in a Penning trap plus Lorentz force: F = e (r) + e v B equation of motion: e ( (r) + v B) + mr = axial oscillation e md z e mz z md z or axial frequency substitution: u x iy radial oscillation c c 4 z modified or reduced cyclotron frequency c e B m u t ue i t i c u z u u c c 4 z magnetron frequency

32 on motion in a Penning trap tion of an ion is the superposition of three harmonic eigenmodes: axial motion (frequency f z ) magnetron motion (frequency f ) modified cyclotron motion (frequency f + ) Typical frequencies q = e, m = 1 u, B = 6 T f - 1 khz f + 1 MHz f + f- fc L.S. Brown, G. Gabrielse, v. d. Phys. 58, 33 (1986).

33 ndau levels of an ion in a Penning trap 3 n + Energy of harmonic oscillators: E = + (n + +1/) + z (n z +1/) - - (n - +1/) amplitudes: 1 n z < > n 1 usually cooling: n + 1 n_ quantum number n but modified cyclotron frequency axial frequency magnetron frequency magnetron motion is unstable!

34 Amplitudes of radial modes

35 Manipulation of ion motion

36 Manipulation of ion motion

37 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

38 1 c m 5 c m SOLTRAP AT SOLDE/CERN B = 6 T ecision Trap: Determination of cyclotron frequency somer separation 141g 141m, E=175keV B = 4.7 T eparation Trap: cumulation Cooling sobar separation A=141 1m 6keV SOLDE 6 V ion beam Linear RFQ trap tardation Cooling cumulation Bunching H. Stolzenberg et al., PRL (199) G. Bollen et al., NM A (1996) H. imbault-hartmann, NM B (1997) F. Herfurth et al., NM A (1)

39 Quadrupole excitation for cyclotron frequency measurement Time of flight 1) Excite radial motion with rf frequency ) Measure radial energy as a function of excitation frequency RF = c = ) peat for different frequency video E - ~1meV E + ~ 1eV M. König, t. J. Mass Spec. on oc. 143(1995) [Hz]

40 TOF [ s] M/M [1-8 ] Norm. tensity [A] Carbon clusters for accuracy checks desorption, fragmentation, and ionization from a C 6 pellet induced by 6 ns, 5 mj laser pulses at 53 nm Source of) the a C6 nm and ing trap) Carbon cluster source +.9 kv +. kv to cooling trap laser beam diaphragms lens TOF cluster spectrum C n n = TOF [ s] 1 C 1 + determination of the systematic error and the achievable accuracy by carbon clusters Mass-dependent error K 1 C 1 1 C 1 8 C 9 1 C 11 1 C 6 1 C 7 1 C 1 1 C kv C6 insulator [Hz] RF Cyclotron resonance Masse [amu] A. Kellerbauer et al., EPJD (3) K. Blaum et al, NM B (3) accuracy: m/m.9 1-9

41 Ca 35 Ca 36 Ca 37 Ca 38 Ca 39 Ca 4 Ca 41 Ca 4 Ca 43 Ca 44 Ca 45 Ca 46 Ca 47 Ca 48 Ca 49 Ca 5 Ca 51 Ca 5 Ca K 35 K 36 K 37 K 38 K 39 K 4 K 41 K 4 K 43 K 44 K 45 K 46 K 47 K 48 K 49 K 5 K 51 K 5 K 53 K Ar 31 Ar 3 Ar 33 Ar 34 Ar 35 Ar 36 Ar 37 Ar 38 Ar 39 Ar 4 Ar 41 Ar 4 Ar 43 Ar 44 Ar 45 Ar 46 Ar 47 Ar 48 Ar 49 Ar 5 Ar Cl 31 Cl 3 Cl 33 Cl 34 Cl 35 Cl 36 Cl 37 Cl 38 Cl 39 Cl 4 Cl 41 Cl 4 Cl 43 Cl 44 Cl 45 Cl 46 Cl 47 Cl 48 Cl 49 Cl S 7 S 8 S 9 S 3 S 31 S 3 S 33 S 34 S 35 S 36 S 37 S 38 S 39 S 4 S 41 S 4 S 43 S 44 S 45 S 46 S 47 S P 6 P 7 P 8 P 9 P 3 P 31 P 3 P 33 P 34 P 35 P 36 P 37 P 38 P 39 P 4 P 41 P 4 P 43 P 44 P 45 P Si Si 3 Si 4 Si 5 Si 6 Si 7 Si 8 Si 9 Si 3 Si 31 Si 3 Si 33 Si 34 Si 35 Si 36 Si 37 Si 38 Si 39 Si 4 Si 41 Si Al Al 3 Al 4 Al 5 Al 6 Al 7 Al 8 Al 9 Al 3 Al 31 Al 3 Al 33 Al 34 Al 35 Al 36 Al 37 Al 38 Al Mg Mg 1 Mg Mg 3 Mg 4 Mg 5 Mg 6 Mg 7 Mg 8 Mg 9 Mg 3 Mg 31 Mg 3 Mg 33 Mg 34 Mg 35 Mg Na 19 Na Na 1 Na Na 3 Na 4 Na 5 Na 6 Na 7 Na 8 Na 9 Na 3 Na 31 Na 3 Na 33 Na 34 Na 35 1 Ne 16 Ne 17 Ne 18 Ne 19 Ne Ne 1 Ne Ne 3 Ne 4 Ne 5 Ne 6 Ne 7 Ne 8 Ne 9 Ne 3 Ne F 15 F 16 F 17 F 18 F 19 F F 1 F F 3 F 4 F 5 F 6 F 7 F 9 8 O 1 O 13 O 14 O 15 O 16 O 17 O 18 O 19 O O 1 O O 3 O N 11 N 1 N 13 N 14 N 15 N 16 N 17 N 18 N 19 N N 1 N N 3 6 C 8 C 9 C 1 C 11 C 1 C 13 C 14 C 15 C 16 C 17 C 18 C 19 C C 5 B 7 B 8 B 9 B 1 B 11 B 1 B 13 B 14 B 15 B 17 B Be 6 Be 7 Be 8 Be 9 Be 1 Be 11 Be 1 Be Li 5 Li 6 Li 7 Li 8 Li 9 Li 1 Li 11 1 He 3 He 4 He 5 He 6 He 7 He 8 He 9 H 1 H H n Br 69 Br 7 Br 71 Br 7 Br 73 Br 74 Br 75 Br 76 Br 77 Br 78 Br 79 Br 8 Br 81 Br 8 Br 83 Br 84 Br 85 Br 86 Br 87 Br 88 Br 89 Br 9 Br 91 Br 9 Br 93 Br As 64 As 65 As 66 As 67 As 68 As 69 As 7 As 71 As 7 As 73 As 74 As 75 As 76 As 77 As 78 As 79 As 8 As 81 As 8 As 83 As 84 As 85 As 86 As 87 As 88 As 89 3 Ge 61 Ge 6 Ge 63 Ge 64 Ge 65 Ge 66 Ge 67 Ge 68 Ge 69 Ge 7 Ge 71 Ge 7 Ge 73 Ge 74 Ge 75 Ge 76 Ge 77 Ge 78 Ge 79 Ge 8 Ge 81 Ge 8 Ge 83 Ge 84 Ge 85 Ge Ga 6 Ga 61 Ga 6 Ga 63 Ga 64 Ga 65 Ga 66 Ga 67 Ga 68 Ga 69 Ga 7 Ga 71 Ga 7 Ga 73 Ga 74 Ga 75 Ga 76 Ga 77 Ga 78 Ga 79 Ga 8 Ga 81 Ga 8 Ga 83 Ga Zn 57 Zn 58 Zn 59 Zn 6 Zn 61 Zn 6 Zn 63 Zn 64 Zn 65 Zn 66 Zn 67 Zn 68 Zn 69 Zn 7 Zn 71 Zn 7 Zn 73 Zn 74 Zn 75 Zn 76 Zn 77 Zn 78 Zn 79 Zn 8 Zn Cu 55 Cu 56 Cu 57 Cu 58 Cu 59 Cu 6 Cu 61 Cu 6 Cu 63 Cu 64 Cu 65 Cu 66 Cu 67 Cu 68 Cu 69 Cu 7 Cu 71 Cu 7 Cu 73 Cu 74 Cu 75 Cu 76 Cu 77 Cu 78 Cu 79 Cu Co 5 Co 51 Co 5 Co 53 Co 54 Co 55 Co 56 Co 57 Co 58 Co 59 Co 6 Co 61 Co 6 Co 63 Co 64 Co 65 Co 66 Co 67 Co 68 Co 69 Co 7 Co 71 Co 7 Co 73 Co 74 Co Fe 46 Fe 47 Fe 48 Fe 49 Fe 5 Fe 51 Fe 5 Fe 53 Fe 54 Fe 55 Fe 56 Fe 57 Fe 58 Fe 59 Fe 6 Fe 61 Fe 6 Fe 63 Fe 64 Fe 65 Fe 66 Fe 67 Fe 68 Fe Mn 46 Mn 47 Mn 48 Mn 49 Mn 5 Mn 51 Mn 5 Mn 53 Mn 54 Mn 55 Mn 56 Mn 57 Mn 58 Mn 59 Mn 6 Mn 61 Mn 6 Mn 63 Mn 64 Mn 65 Mn Cr 43 Cr 44 Cr 45 Cr 46 Cr 47 Cr 48 Cr 49 Cr 5 Cr 51 Cr 5 Cr 53 Cr 54 Cr 55 Cr 56 Cr 57 Cr 58 Cr 59 Cr 6 Cr 61 Cr 6 Cr 63 Cr 64 3 V 43 V 44 V 45 V 46 V 47 V 48 V 49 V 5 V 51 V 5 V 53 V 54 V 55 V 56 V 57 V 58 V 59 V 6 V 61 4 Ti 39 Ti 4 Ti 41 Ti 4 Ti 43 Ti 44 Ti 45 Ti 46 Ti 47 Ti 48 Ti 49 Ti 5 Ti 51 Ti 5 Ti 53 Ti 54 Ti 55 Ti 56 Ti 57 Ti r 165 r 166 r 167 r 168 r 169 r 17 r 171 r 17 r 173 r 174 r 175 r 176 r 177 r 178 r 179 r 18 r 181 r 18 r 183 r 184 r 185 r 186 r 187 r 188 r 189 r 19 r 191 r 19 r 193 r 194 r 195 r 196 r 197 r Mt 66 Mt Hs 63 Hs 64 Hs 65 Hs 67 Hs Bh 6 Bh 61 Bh 6 Bh Sg 58 Sg 59 Sg 6 Sg 61 Sg 63 Sg 65 Sg Db 55 Db 56 Db 57 Db 58 Db 6 Db 61 Db 6 Db Rf 53 Rf 54 Rf 55 Rf 56 Rf 57 Rf 58 Rf 59 Rf 6 Rf 61 Rf 6 13 Lr 5 Lr 53 Lr 54 Lr 55 Lr 56 Lr 57 Lr 58 Lr 59 Lr 6 Lr 61 Lr 6 1 No 5 No 51 No 5 No 53 No 54 No 55 No 56 No 57 No 58 No 59 No 6 No 6 11 Md 45 Md 46 Md 47 Md 48 Md 49 Md 5 Md 51 Md 5 Md 53 Md 55 Md 56 Md 57 Md 58 Md 59 Md Fm 4 Fm 43 Fm 44 Fm 45 Fm 46 Fm 47 Fm 48 Fm 49 Fm 5 Fm 51 Fm 5 Fm 53 Fm 54 Fm 55 Fm 56 Fm 57 Fm 58 Fm Es 41 Es 4 Es 43 Es 44 Es 45 Es 46 Es 47 Es 48 Es 49 Es 5 Es 51 Es 5 Es 53 Es 54 Es 55 Es 56 Es Cf 37 Cf 38 Cf 39 Cf 4 Cf 41 Cf 4 Cf 43 Cf 44 Cf 45 Cf 46 Cf 47 Cf 48 Cf 49 Cf 5 Cf 51 Cf 5 Cf 53 Cf 54 Cf 55 Cf Bk 38 Bk 4 Bk 4 Bk 43 Bk 44 Bk 45 Bk 46 Bk 47 Bk 48 Bk 49 Bk 5 Bk Cm 38 Cm 39 Cm 4 Cm 41 Cm 4 Cm 43 Cm 44 Cm 45 Cm 46 Cm 47 Cm 48 Cm 49 Cm 5 Cm Am 3 Am 3 Am 34 Am 35 Am 36 Am 37 Am 38 Am 39 Am 4 Am 41 Am 4 Am 43 Am 44 Am 45 Am 46 Am Pu 8 Pu 9 Pu 3 Pu 31 Pu 3 Pu 33 Pu 34 Pu 35 Pu 36 Pu 37 Pu 38 Pu 39 Pu 4 Pu 41 Pu 4 Pu 43 Pu 44 Pu 45 Pu 46 Pu Np 5 Np 6 Np 7 Np 8 Np 9 Np 3 Np 31 Np 3 Np 33 Np 34 Np 35 Np 36 Np 37 Np 38 Np 39 Np 4 Np 41 Np 4 Np 43 Np Md sf p stable Mass measured at SOLTRAP ference mass C 1 C C 3 C 4 C 4 C 5 C 6 C 7 C 8 C 9 C 1 C 11 C 1 C 11 C 1 C 13 C 14 C 15 C 16 C 17 C 18 C 19 C 18 C 19 C C 1 C Carbon clusters for absolute mass measurements Mass measured at SOLTRAP ference mass

42 Phys. v. Lett. 9, 1151, dito 93, 75, dito 93, 1581 (all 4)

43 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

44 Excitation of on tion + (-) RF exc + (-) Phase Splitter (+) - (+)

45 Detection of on tion red.cyc,(+)

46 Detection of on tion A dipolar RF field with amplitude V RF excites ions during the time T RF into a coherent cyclotron motion at a larger radius. r red.cyc,( ) V R RF T B e image current induced in the detection plates is given by RF nq VRFT ( t) mr RF sin ωt e line width (FHM) of the induced signal only depends on the detection duration T detect. red.cyc,( ) T 1 detect.

47 Fourier Transformation Time domain: transient s equency domain: mass spectrum m/z

48 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

49 Non neutral electron and ion plasmas vortex crystals ion crystals Fluorescence of trapped Ca + (G. erth /Mainz) Electrons in a Malmberg trap (C.F. Driscoll/ San Diego) For an overview see: Non neutral plasma physics V F. Anderegg, L.S., C.F. Driscoll (eds.) AP conf. proc. 66 ()

50 troduction inciples of trapping Alternative ion trapping techniques ul trap Penning trap SOLTRAP FT-CR MS Non-neutral plasma Electrostatic trap

51 Photon optics - ion optics Optical resonator rticle resonator E k, q V V>E k /q V M Trapping of fast ion beams using electrostatic field Courtesy of D. Zajfman L

52 Electrostatic trap R.N. olf et al., t. J. Mass Spectrom (13) 13 F. ienholtz et al., Nature 498 (13) 346 Masses of exotic calcium isotopes pin down nuclear forces

53 Everything s a trap if you are not careful.