1 / 62

Pan-American Advanced Studies Institute on Rare Isotopes: Rare isotope production and FRIB

Pan-American Advanced Studies Institute on Rare Isotopes: Rare isotope production and FRIB. 10 August, 2010 Bradley M. Sherrill FRIB Chief Scientist. Broad Overview of Talk. Production of rare isotopes Reaction mechanisms Facilities (FRIB) Tests of fundamental symmetries

aviv
Download Presentation

Pan-American Advanced Studies Institute on Rare Isotopes: Rare isotope production and FRIB

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pan-American Advanced Studies Institute on Rare Isotopes: Rare isotope production and FRIB 10 August, 2010 Bradley M. Sherrill FRIB Chief Scientist

  2. Broad Overview of Talk Production of rare isotopes Reaction mechanisms Facilities (FRIB) Tests of fundamental symmetries Effects of symmetry violations are amplified in certain nuclei Societal applications and benefits Bio-medicine, energy, material sciences, national security Goal: Try to talk about something not previously covered in detail at PASI

  3. How do we make rare isotopes? Lithium-7 3 protons, 4 neutrons Suppose we want to study Lithium-11 3 protons, 8 neutrons

  4. An alternative Start with a nucleus with enough neutrons and to make 11Li (e.g. 18O) and remove protons 18O 17N 16C 15B 14Be 18O 11Li 11Li 12Li 13Li

  5. Creation of new isotopes 18-Oxygen Collision 11-Lithium To use this mechanism (projectile fragmentation), an 18O nucleus is accelerated to a velocity of greater than around 50 MeV/u.

  6. Cross Section for Production Beam Target One nucleon removal Around 50 mb (light nuclei) P ≈ 5% 2n removal 5 mb P = .5% And so on Rule of thumb .1 x for each neutron removed 18O rb rt 17N 16C 15B Actual: 16O +12C interaction cross section: 1000 mb (measured at 970 MeV/u) Note: Above around 300 MeV/u the interaction length is shorter than the electronic stopping range of the 16O 14Be 11Li 12Li 13Li

  7. Rare Isotope Production Mechanisms • There are a variety of nuclear reaction mechanisms used to add or remove nucleons (items for the jargon page) • Spallation • Fragmentation • Coulomb fission (photo fission) • Nuclear induced fission • Light ion transfer • Fusion-evaporation (cold, hot, incomplete, …) • Fusion-Fission • Deep Inelastic Transfer • Massive transfer There is no best method. Many still have interesting physics question relevant to their application to produce rare isotopes.

  8. Production Methods – Low Energy • (p,n) (p,nn) etc. • Ep < 50 MeV • Used for the production of medical isotopes. • Selective, large production cross sections (100 mb), and intense (500 mA) primary beams. • Used at HRIBF(ISOL), LLN (ISOL), ANL (in-flight) and Notre Dame (in-flight), Texas A&M (in-flight with MARS, e.g. 23Al) • Fusion-Evaporation • Low energy 5-15 MeV/A and “thin” targets (mg/cm2) • Selective with fairly large production cross sections. • Used at for example ANL(in-flight), JYFL (Jyväskylä) • Fusion-Fission – 238U+12C (basis of Laser acceleration idea D. Habs et al.)

  9. Example of production by fusion-evaporation • Beam and target fuse (post fusion nucleons may be evaporated) • Variant – Incomplete fusion where particles are lost prior to the complete fusion of the participants • High, specific production cross sections • Example: 3He (58Ni, 60Zn)n, ENi = 250 MeV • Production cross section from PACE4 (A.Gavron, Phys.Rev. C21 (1980) 230-236): 60 mb • 1 g/cm2 target • Yield of 60Zn is 7x107/pμA (LBL 88-inch has 10 pμA of 58Ni)

  10. Low Energy - Continued • Multi-Nucleon Transfer reactions (two body final state) • Significant cross section between 10 - 50 MeV/A • High production of nuclei near stability. • Multi-nucleon reactions can be used to produce rare or more neutron rich nuclei, e.g. GSI mass separator had a program to study neutron rich f-p shell nuclei using neutron transfer. • Deeply inelastic reactions (10 - 50?/A MeV/u range) • Deep inelastic - KE of the beam is deposited in the target. Products are emitted away from the beam axis. • Was used to first produce many of the light neutron rich nuclei • Is used to study neutron rich nuclei since the products are “cooler” and fewer neutrons are evaporated than in fusion reactions. • Large cross sections for production of some exotic isotopes

  11. Deep Inelastic Transfer Example R Broda J Phys G 32, R151-R192 (2006) – work at ANL, recent with GAMMASPHERE I = 106/s σ = 1 mb 20 mg/cm2 Yield = 700/hr Models by Tasson-Got based on Monte Carlo (L. Tassan-Got and C. Stefan, Nucl. Phys. A524, 121 (1991)) and statistical decay of the product GEMINI (R. Charity et al., Nucl. Phys. A483, 371 (1988))

  12. Production Mechanisms – High Energy • Fragmentation (FRIB, NSCL, GSI, RIKEN, GANIL) • Projectile fragmentation of high energy (>50 MeV/A) heavy ions • Target fragmentation of a target with high energy protons or light HIs. In the heavy ion reaction mechanism community this would include intermediate mass fragments. • Spallation (ISOLDE, TRIUMF-ISAC, EURISOL, SPES, …) • Name comes from spalling or cracking-off of target pieces. • One of the major ISOLDE mechanisms, e.g. 11Li made from spallation of Uranium. • Fission (HRIBF, ARIEL, ISAC, JYFL, …) • There is a variety of ways to induce fission (photons, protons, neutrons (thermal, low, high energy) • The fissioning nuclei can be the target (HRIBF, ISAC) or the beam (GSI, NSCL, RIKEN, FAIR, FRIB). • Coulomb Breakup (GSI) • At beam velocities of 1 GeV/n the equivalent photon flux as an ion passes a target is so high the GDR excitation cross section is many barns.

  13. Spallation From Wikimedia Commons: http://en.wikipedia.org/wiki/File:Spallation.gif

  14. Universality of Production Cross Sections Na isotopes H Ravn, CERN

  15. Fragmentation (Projectile) • Pictorial model (above 50 MeV/u) • Parameterization of cross sections (EPAX 2 Sümmerer and Blank, Phys.Rev. C61(2000)034607) • Close related to Silverberg-Tso parameterization • Parameters fit to experimental data (exponential form function of removed nucleons) • Energy independent cross sections • Production cross section does not depend on the target • More detailed models (e.g. ABRABLA (K-H Schmidt et al. - See http://www-win.gsi.de/charms/) • Internuclear Cascade projectile target

  16. Limiting Fragmentation The production yield of residues saturates with a total beam energy of a few GeV. Limiting Fragmentaton H. Ravn - “The saturation cross-section for more exotic species may well first be reached beyond 5 GeV.” Kaufman and Steinberg, PRC 22 (80) 167.

  17. Production cross section depends on mass • Cross section logarithmic with Qg (Tarasov PRC75) • Qg = ME(beam) – ME(fragment) • This provides a means to determine (roughly) the binding energy(M.B. Tsang et al., Phy Rev C DOI:10.1103/PhysRevC.76.041302) • NOTE: The magnitude of the production cross sections do depend on the target 48Ca + W 140 MeV/u 48Ca + Be 140 MeV/u

  18. Production Cross Sections Measured 76Ge Fragmentation at 130 MeV/u Tarasov et al. Phys. Rev. Lett. 102, 142501 (2009)

  19. Fission • Pictorial Model • ABRABLA - See http://www-win.gsi.de/charms/ for excellent details (Schmidt et al.) – J. Benlluire et al. Phy. Rev. C 78 054605 (2008) • LISE++ Fission Models (Tarasov et al.) LISE++ • The initial fragmentation step produces a wide range of excitation energies • Can use photons, protons, nuclei, etc. to induce the fission • Observation: For 500 MeV/u238U the fragmentation and fission cross sections are approximately equal projectile target

  20. Fission Cross Sections Low energy fission can lead to higher yields for certain nuclides. This is the basis of the electron driver upgrade of the TRIUMF (ARIEL).

  21. Summary of High Energy Production Mechanisms • CHARMS http/www.gsi.de/charms

  22. Nuclear Chart in 1966 The availability of rare isotopes over time The good old days Less than 1000 known isotopes Available today New territory to be explored with next-generation rare isotope facilities blue – around 3000 known isotopes

  23. Rare Isotope Production Techniques • Target spallationand fragmentation by light ions (ISOL – Isotope separation on line) • Photon or particle induced fission • In-flight Separation following nucleon transfer, fusion, projectile fragmentation/fission Target/Ion Source beam Post Acceleration Accelerator Uranium Fission Neutrons target Reactor Post Acceleration Electrons Accelerator Protons Accelerator beam Beam Beams used without stopping Fragment Separator target Post Acceleration Gas catcher/ solid catcher + ion source

  24. Jargon • ISOL • In-flight (projectile fragmentation is one production mechanism) Target/Ion Source Post Acceleration Accelerator Accelerator Beam Fragment Separator

  25. Types of ISOL Ion Sources Beam into page Target P. Butler

  26. Production is only one part of the equation I = sIbTuseableediffedeseeffeis_effeaccel_eff H. Ravn • s - production cross section • Ib - beam intensity • Tuseable - usable target thickness • ediff – diffusion efficiency • edes – desorption efficiency • eeff – effusion efficiency • eis_eff - ionization efficiency • eaccel_eff - acceleration efficiency target

  27. fragment yield after target fragment yield after wedge fragment yield at focal plane In-Flight Production Example: NSCL’s CCF D.J. Morrissey, B.M. Sherrill, Philos. Trans. R. Soc. Lond. Ser. A. Math. Phys. Eng. Sci. 356 (1998) 1985. K500 Example: 86Kr → 78Ni ion sources coupling line 86Kr14+, 12 MeV/u K1200 A1900 focal plane p/p = 5% production target transmission of 65% of the produced 78Ni 86Kr34+, 140 MeV/u stripping foil wedge

  28. Exotic Beams Produced at NSCL More than 1000 RIBs have been made – morethan 830 RIBs have been used in experiments 12 Hours for a primary beam change; 3 to 12 hours for a secondary beam

  29. Advantages/Disadvantages of ISOL/In-Flight In-flight: GSI RIKEN NSCL FRIB GANIL ANL RIBBAS … • Provides beams with energy near that of the primary beam • For experiments that use high energy reaction mechanisms • Luminosity (intensity x target thickness) gain of 10,000 • Individual ions can be identified • Efficient, Fast (100 ns), chemically independent separation • Production target is relatively simple ISOL: HRIBF ISAC SPIRAL ISOLDE SPES EURIOSOL • Good Beam quality (πmm-mr vs. 30πmm-mr transverse) • Small beam energy spread for fusion studies • Can use chemistry (or atomic physics) to limit the elements released • 2-step targets provide a path to MW targets • High beam intensity leads to 100x gain in secondary ions 400kW protons at 1 GeV is 2.4x1015 protons/s

  30. Sensitivity of Production of Rare Isotopes in Flight The production cross sections for the most exotic nuclei are extremely small; but, facilities can have tremendous sensitivity. The projectile intensity at FRIB (48Ca 400 kW, ≅ 2x1014 ion/s) is such that production cross sections as low as 3x10-20 b (30 zeptobarns, 3x10-48 m2 ) are useful. Neutrino elastic scattering cross sections are Comparison super heavy elements are produced with .5 pb, 5x10-12 b (e.g. element 113 at RIKEN in cold fusion)

  31. World view of rare isotope facilities Ariel Black – production in target Magenta – in-flight production

  32. Gordon Ball, TRIUMF

  33. Present status of the Ariel Project • 50 MeV, 500 kW superconducting e-linac funded • matching funding from BC province for buildings (funded June 2010) • second proton beamline deferred until next 5YP Gordon Ball, TRIUMF

  34. HRIBF 25MV Tandem Electrostatic Accelerator Injector for Radioactive Ion Species 1 (IRIS1) Injector forStable Ion Species (ISIS) Oak Ridge Isochronous Cyclotron (ORIC) Enge Spectrograph Daresbury Recoil Separator (DRS) High Power Target Laboratory (HPTL) Recoil Mass Spectrometer (RMS) On-Line Test Facility (OLTF)

  35. Fission products of 252Cf spontaneous fission stopped in gas and accelerated CARIBU gives access to exotic beams not available elsewhere. Physics with beams from CARIBU (1 & 2 nucleon transfer reactions) needs the new energy regime opened by the Energy Upgrade (12 MeV/u) . Solenoid Spectrometer greatly expands the effectiveness of both the fission fragment beams and the existing in-flight RIB program at these higher energies. CARIBU upgrade Argonne National Laboratory: CARIBU & Energy Upgrade & HELIOS: Unique Synergy CARIBU ATLAS Energy Upgrade HELIOS R. Janssens ANL

  36. Yields from the ANL Upgrade Guy Savard, ANL

  37. Facility for Rare Isotope Beams, FRIB Broad Overview • Driver linac capable of E/A  200 MeV for all ions, Pbeam 400 kW • Early date for completion is 2018; TPC 613M$ • Upgrade options (tunnel can house E/A = 400 MeVuranium driver linac, ISOL, multi-user capability …) Thomas Glasmacher Project Manager KonradGelbke Director

  38. Overview of the FRIB Facility • Lowest cost configuration that meets technical requirements • Upgradable • Reviewed by various advisory committees • Endorsed by CD1 Lehman review July 2010

  39. FRIB Cutaway View • Experimental areas and scientific instrumentation for fast, stopped and reaccelerated beams • Beam power ramps from 10 kW in year 1 to 400 kW in year 4

  40. Details of the FRIB Layout Superconducting RF cavities 4 types ≈ 344 total Epeak ≈ 30 MV/m Β=0.04 β = 0.08 β = 0.2 β = 0.5

  41. Fragment Separator Details • Marc Hausman; Project leader Unused isotopes could be collected at the beam dump and mass selection slits • Self-contained target building • Full remote-handling to maximize facility efficiency (target change/week) • Target applicable to light and heavy beams (about 1/3 of power lost in target) • Beam dump for unreacted primary beam for up to 400 kW beam power

  42. The Five-Minute Rap Version Rare Isotope Rap by Kate McAlpine (also did the LHC Rap)

  43. LISE++ Simulation Code The code operates under Windows and provides a highly user-friendly interface. It can be downloaded freely from the following internet address: O. Tarasov, D. Bazinet al. http://www.nscl.msu.edu/lise

  44. Fragmentation at 400MeV/u • LISE++ Simulation for 124Xe and 208Pb fragmentation Momentum distrib. 100Sn Relatively ‘easy’ to collect due to small phase space 200W • Angles ≤ ± 20 mrad • Momentum ± 3 - 8 % M. Hausmann, T. Nettleton

  45. In-Flight Fission at 400 MeV/u • LISE++ Fission model for 238U pf pb 132Sn 76Ni • Angles ± 40 - 60 mrad • Rigidity ± 6 - 10 % • Plus correlations due to fission kinematics M. Hausmann, T. Nettleton

  46. Production Target and Beam Dump Area Grouted floor over shield blocks Target floor shielding Beam dump floor shielding

  47. Cyclotron gas stopper Linear gas stopper Solid stopper (LLN (Belgium), KVI (Netherlands)) Key FRIB component: Beam Stopping Fast ions He gas G. Savard, ANL, D. Morrissey NSCL LLN, GSI, et al. Beams for precision experiments at very low-energies or at rest and for reacceleration

  48. Preliminary Performance Baseline Schedule for 2018 Early Completion – CD-4 in 2020 CALENDAR YEAR TPC covers schedule range

  49. What New Nuclides Will FRIB Produce? • FRIB will produce more than 1000 NEW isotopes at useful rates (4500 available for study) • Theory is key to making the right measurements • Exciting prospects for study of nuclei along the drip line to mass 120 (compared to 24) • Production of most of the key nuclei for astrophysical modeling • Harvesting of unusual isotopes for a wide range of applications Rates are available at http://groups.nscl.msu.edu/frib/rates/

  50. FRIB Organizational Structure and User Input into the Project

More Related