1 / 12

The 2-Body Photodisintegration Reaction 4 He( g ,n) 3 He below 30 MeV

The 2-Body Photodisintegration Reaction 4 He( g ,n) 3 He below 30 MeV. John Kelley , R. Raut, G. Rusev, S.C. Stave, A.P. Tonchev,  W. Tornow Triangle Universities Nuclear Laboratory North Carolina State University Duke University.

yauvani-sharma
Download Presentation

The 2-Body Photodisintegration Reaction 4 He( g ,n) 3 He below 30 MeV

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. The 2-Body Photodisintegration Reaction 4He(g,n)3He below 30 MeV John Kelley, R. Raut, G. Rusev, S.C. Stave, A.P. Tonchev,  W. Tornow Triangle Universities Nuclear Laboratory North Carolina State University Duke University

  2. “Equality” vs Inequality of 4He(g,n/p)3He/3H sWhat are the Implications? • Charge Symmetry • Isospin Mixing

  3. Present State

  4. 4He(g,3He)n below 30 MeV at the High Intensity g-ray Source (HIGS) Compton backscatter FEL photons from electrons in a storage ring FEL.

  5. Photon Flux from Plastic Scintillator Paddle Efficiency measured by comparison with NaI Pb 10” x 12” NaI detector Well understood efficiency g-ray beam Plastic scintillator paddle / PMT Pb 10 mm Collimator

  6. Experimental Setup PMT 3He-Xe gas scintillator Pb g-ray beam Plastic Scintillator paddle/PMT Pb 10 mm Collimator

  7. Active 4He/Xe 5 cm diameter scintillation cell max 50 mm diameter

  8. 4He/Xe scintillation cell vs Xe scintillation cell “target out”

  9. Photon-induced reaction thresholds (in MeV) Isotope Nat. Abundance (%) (g,p) (g,a) (g,n) (g,2n) (g,na) xenon isotopes 128 1.92 8.17 1.77 9.61 16.84 11.19 131 21.18 8.82 2.55 6.61 15.87 8.85 136 8.87 9.93 3.66 7.99 14.44 11.73 magnesium isotopes 24 78.99 11.69 9.31 16.53 26 11.01 14.15 10.61 11.09 oxygen isotopes 16 99.762 12.13 7.16 15.67 18 0.200 15.94 6.23 8.05 He isotopes 4 99.762 19.81 - 20.58 Atomic effects Eg=27 MeV 4He+g -> 3He(1.6 MeV) & n (4.8 MeV)

  10. Busy Inhibit Linear Gate High Rate/ High ThresholdAnti-Pileup Circuit • High Threshold – minimize multi-pulse pileup in the CFD • Linear Gate • Dt~100 ns – (with inhibit Dt~10 us) • minimize pileup in Spectroscopic Amplifier Scaler PULSER FIFO AMP AMP FIFO FIFO AMP inhibit 3He Cell CFD Scaler GDG Paddle AMP Logic Scaler Computer Busy

  11. Results • Proof of principle • Beamtime expected in the next quarter

More Related