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AMS for astrophysics, p-process work and other. Michael Paul, Philippe Collon. 146 Sm p-process Strong requirements on ATLAS “beam-switching” capabilities Very important for MANTRA Over the years there have been campaigns to detect
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AMS for astrophysics, p-process work and other Michael Paul, Philippe Collon
146Sm p-process • Strong requirements on ATLAS “beam-switching” capabilities Very important for MANTRA • Over the years there have been campaigns to detect • 44Ti (40Ca(a,g)44Ti during a-rich freeze-out during core-collapse supernova events) • Stellar (n,g) cross-section of 62Ni (slow-s-process)
P-nuclei and the p-process Stable: 74Se, 78Kr, 84Sr, 92Mo, 94Mo, 96Ru, 98Ru, 102Pb, 106Cd, 108Cd, 112Sn, 113Sn, 114Sn, 115Sn, 120Te, 124Xe, 126Xe, 130Ba, 132Ba, 136Ce, 138La, 138Ce, 144Sm, 152Gd, 156Dy, 162Er, 164Er, 168Yb, 174Hf, 180Ta, 180W, 184Os, 190Pt, 196Hg “Long-lived”: 93Mo, 109Cd, 133Ba, 241Gd, 157Tb, 158Tb, 173Lu, 174Lu, 193Pt,205Pb, 207Bi, 208Bi, (228-231Th)
AMS identification and counting of 146Sm discrimination from 146Nd impurities
FN TANDEM INJECTOR GFM Spectrograph ECR-II ATLAS LINAC ECR-I PII BOOSTER LINAC Argonne ATLAS facility: Accelerated Ions: iso-(m/q) 146Sm22+,146Nd22+ m/q=146/22 Pilot beam (by m/q scaling): 80Kr12+,147Sm22+, 152Sm23+
146Nd 146Sm after data filtering using time-of-flight spectrum 146Sm/147Sm ~ 10-12
New half-life: 68±7 million years (compared to 103±5 million years)
62Ni(n,g)63Ni cross section (1) Implantation (2) extraction (3) AMS measurement AMS measurement based on gas-filled magnet technique (split-pole Enge) to separate 63Ni from 63Cu
H. Nassar et al. Phys. Rev. Lett. 96(2006) 041102 Production of 44Ti using a 40Ca beam Separation of the 44Ti and 44Ca isobars
AMS measurement requirements • VERY stable ECR conditions • High and STABLE transmission through the accelerator • Overall stability and repeatability (especially for absolute measurements) • A number cannot be made at tandem facilities • Most of the time is spent in setup and tuning last at least a week of beamtime