0
Charge exchange and spectroscopy with isolated             highly-charged ions                   Nicholas D. Guise        ...
Overview  GoalEngineer highly-charged ions (HCI) of interest in metrology, astrophysics,plasma diagnostics, and collision ...
Permanent Magnet Penning Traps            One-Magnet Trap                                      Two-Magnet Trap• B field pr...
Experiment Region              TOF Detector:              8 mm diameter                                                   ...
Ion Capture and Detectiont=0                              t=tcapture ≈ 17 µs          t=tstorage ≈ 200ms       t ≈ tstorag...
Ion Extraction and Capture Timing
Ion Energy             Ion energy             ~ 5.5 eV
Ion Charge Exchange          sum of all         bare Ne        charge state evolution          charge states      nuclei  ...
Ion Storage: Pressure Dependence       Parameters     Two-Magnet Trap       V0≈ 2.5 kV   ∆V=Vring-Vendcap = 25 V
Long-Term Focus: H-like ions in Circular                   Rydberg States                                       • Theory m...
New Apparatus for Low Charge StatesElectrongun         Ion                                    18 mm            production ...
Summary• Unitary architecture NdFeB Penning traps are used to capture and  store highly charged ions extracted from the NI...
Upcoming SlideShare
Loading in...5
×

Charge exchange and spectroscopy with isolated highly-charged ions

426

Published on

Talk given by Nicholas Guise (NIST) at DAMOP12, Orange County, California, USA (08/06/12)

Published in: Education, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
426
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
3
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "Charge exchange and spectroscopy with isolated highly-charged ions"

  1. 1. Charge exchange and spectroscopy with isolated highly-charged ions Nicholas D. Guise Samuel M. Brewer, Joseph N. Tan Quantum Measurement Division National Institute of Standards and Technology Gaithersburg, MD 20899 8 June 2012
  2. 2. Overview GoalEngineer highly-charged ions (HCI) of interest in metrology, astrophysics,plasma diagnostics, and collision studies q/m Basic Scheme analyzing magnet fs comb 1) Extract HCI from EBIT source ion 2) Recapture in Penning trap trap laser ions 3) Study recaptured ions -charge exchange -optical spectroscopy CX beam MCP detector EBIT (electron beam ion trap)
  3. 3. Permanent Magnet Penning Traps One-Magnet Trap Two-Magnet Trap• B field provided by one NdFeB magnet • B field more homogeneous near center• Magnet also functions as ring electrode • Holes in ring provide optical access• Simple construction with copper endcaps • Iron electrodes shape field profile J.N. Tan, S.M. Brewer, and N.D. Guise, Rev. Sci. Instrum. 83, 023103 (2012)
  4. 4. Experiment Region TOF Detector: 8 mm diameter Photomultiplier <1 ns rise time TubeNe10+ Beam Spot Time-of-Flighton Position-Sensitive MCP MCP Detector (TOF), on retractable translator XY Position Sensitive MCP 1-Magnet Detector Penning Trap 2-Magnet RF Trap/ Penning Trap Lens/Filter
  5. 5. Ion Capture and Detectiont=0 t=tcapture ≈ 17 µs t=tstorage ≈ 200ms t ≈ tstorage+1 µsextract ions pulse trap closed pulse trap open ions arrive at MCPfrom EBIT to capture ions to dump ions detectorEBIT MCP capture dump applied voltage Front Endcap Ring Back Endcap
  6. 6. Ion Extraction and Capture Timing
  7. 7. Ion Energy Ion energy ~ 5.5 eV
  8. 8. Ion Charge Exchange sum of all bare Ne charge state evolution charge states nuclei H-like Ne He-like Ne10+ Ne bare Ne only nuclei Parameters H-like Two-Magnet Trap Ne He-like Ne V0 ≈ 2.5 kV∆V=Vring-Vendcap = 25 V
  9. 9. Ion Storage: Pressure Dependence Parameters Two-Magnet Trap V0≈ 2.5 kV ∆V=Vring-Vendcap = 25 V
  10. 10. Long-Term Focus: H-like ions in Circular Rydberg States • Theory more accurate than for Electron Probability Hydrogen S states due to: Distribution • negligible interactions with the nucleus • accuracy of calculated corrections, including QED effects • |n› → |n-1› transitions are accessible to optical frequency combnucleus: Ze+ electron state: | n,l,m › |m|=l=n-1 U.D. Jentschura, P.J. Mohr, J.N. Tan, and B.J. Wundt, Phys. Rev. Lett. 100, 160404 (2008).
  11. 11. New Apparatus for Low Charge StatesElectrongun Ion 18 mm production TOF detector region Experiment region with two-magnet Penning trap
  12. 12. Summary• Unitary architecture NdFeB Penning traps are used to capture and store highly charged ions extracted from the NIST EBIT.• Captured ion species include Ne10+, Ne9+, Ne8+, Ar16+, Ar15+, Ar14+, Ar13+, N7+, and Kr17+.• Ion storage times of order 1 second are limited primarily by collisions with residual gas at 300 K.• Ongoing experiments include studies of charge exchange, optical measurements of metastable lifetimes (upcoming talk by S. Brewer).• New apparatus will utilize similar NdFeB construction for a room- temperature “mini-EBIT” source, for planned spectroscopy with low-Z hydrogen-like ions.
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×