Highly Charged Ion Astrophysics in the Laboratory: A New User Facility at Clemson University. Chad E. Sosolik Dept. of Physics and Astronomy

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1 Highly Charged Ion Astrophysics in the Laboratory: A New User Facility at Clemson University Chad E. Sosolik Dept. of Physics and Astronomy

2 Clemson s New User Facility Highly charged ion (HCI) production Electron Beam Ion Trap (EBIT) Ion extraction and transport Custom beamline HCI-materials interactions UHV vacuum chambers (target, prep, etc.) Measurement/Detection tools ions, electrons, mass loss, x-rays

3 Proposal MRI-R 2 Five Emphasis Areas Surface and Interface Nanoscience Electronic Materials and Devices Fusion-Relevant Materials Studies Laboratory Astrophysics Radiation Effects on Electronics

4 Proposal MRI-R 2 Building a User/Collaborator Base Five Emphasis Areas Surface and Interface Nanoscience Electronic Materials and Devices Fusion-Relevant Materials Studies Laboratory Astrophysics Radiation Effects on Electronics

5 Clemson University Electron Beam Ion Trap (CUEBIT) Funded (March 15, 2010) National Science Foundation Equipment/Facilities Funds ($1.65 million) Clemson University Staff Operator/Technician (search soon!) Fully renovated laboratory space (in progress) Three years of committed shop time

6 The EBIT in CUEBIT Born 29 October 1986 LLNL Mort Levine and Ross Marrs with the first EBIT at LLNL.

7 The EBIT in CUEBIT A Penning trap with an intense, monoenergetic, electron beam down the axis.

8 The EBIT in CUEBIT E1 (200 V) E2 (100 V) E3 (200 V) B field Energy (q*v) Trapped Ions (or electrons) X (position)

9 Highly Charged Ions Definition(s) An atom missing more than 1or 2 electrons An atom missing several dozen electrons Any atom that has been stripped of a large number of electrons (Q» 1) such that the total energy yielded during reneutralization (E 0 ) is outside the realm of ordinary experience with laboratory ions (E 0» 10 ev) Ref: J.D. Gillaspy, J. Phys. B. 34, R93 (2001).

10 Highly Charged Ions Neutralization Energy the sum of all the ionization energies of the charge states at and below the ion

11 Highly Charged Ions Neutralization Energy Hydrogen (scaled) Xenon (isonuclear sequence)

12 Highly Charged Ions Neutralization Energy

13 HCI-Materials Interactions The Basic Picture x-ray x-ray q+ e - e - e - e- Resonant neutralization e - and x-ray emission Desorption and sputtering q- hollow atom

14 CUEBIT: The Plan

15 CUEBIT: The Plan HCI Beam

16 CUEBIT: The Plan HCI Beam X-rays Electrons Sputtered Particles Scattered Ion/Atoms Real-time mass loss Sample control (heated/cooled)

17 HCIs: Laboratory Astrophysics Cosmic chronometers (Cosmochronometry) time span of nucleosynthesis in our galaxy Example: decay products of Re-187 in meteorites Neutral Re half life of 4.2 x 10 9 yrs Highly ionized Re half life of 33 yrs Ref: F. Bosch et al., Phys. Rev. Lett. 77, 5190(1996). Decay proceeds more rapidly through electron capture than escape

18 HCIs: Laboratory Astrophysics X-ray astrophysics radiation encountered is signature of complex events exploding stars, matter falling into black holes highly ionized matter Two facts: Earth s atmosphere is opaque to x-rays HCIs don t occur naturally on Earth How do you test detectors and the theoretical models used to interpret your data?...with an EBIT...

19 HCIs: Laboratory Astrophysics Charge Exchange Measurements Neutral gas injected into the EBIT Detection of emitted X-rays Comet in a lab Charge exchange between O 8+, Ne 10+ and various targets (e.g. H 2 0, CH 4, and CO 2 ) Ref: S. Otranto, R.E. Olson, andp. Beiersdorfer, Phys. Rev. A 73, (2006) Absolute excitation cross sections Calibration of intensity ratios the 3d-2p to 3s-2p transitions in neon-like Fe 16+

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21 HCIs: Laboratory Astrophysics Materials synthesis in space Nanodiamond dust postulated in the interstellar medium Related to spectral signature of quasars Ref: L. Binette et al., Ap. J. 631, 661(2005). Found in meteorites HCI irradiation of graphite (in the laboratory) Nanoscale diamond-like structure formation Ref: E. Sideras-Haddad et al., Nucl. Instrum. Meth. B 267, 2774 (2005).

22 CUEBIT: What should we plan for? HCI Beam X-rays Electrons Sputtered Particles Scattered Ion/Atoms Real-time mass loss Sample control (heated/cooled) From the NSF-MRI-R 2 proposal: We will: i) operate as a user facility for ground-based exposures of astrophysically relevant surfaces, and ii) conduct fundamental research into astrophysical ices and dust on supported substrates as they relate to the evolution of interstellar matter.

23 CUEBIT: What should we plan for? HCI Beam X-rays Electrons Sputtered Particles Scattered Ion/Atoms Real-time mass loss Sample control (heated/cooled) Thanks to The Organizers National Science Foundation

24 Highly Charged Ion Astrophysics in the Laboratory: A New User Facility at Clemson University Chad E. Sosolik Dept. of Physics and Astronomy sosolik@clemson.edu