Science

A prime justification for the accelerated beams facility (ISAC) at TRIUMF is the study of radiative capture reactions using radioactive beams. Some key reactions for heavy-element synthesis during explosive burning in stars involve radioactive reactants of short half-lives. Table 1 lists some of these astrophysically-interesting reactions of the initial ISAC program. The limited intensity of radioactive beams and the small cross sections for capture reactions require a detection system which has both high efficiency for detection of reaction products and highly effective suppression of beam background. The DRAGON system has been designed for radioactive beam capture studies at ISAC; with support from NSERC, TRIUMF and agencies outside Canada, construction is under way on a windowless gas target, electromagnetic mass separator (EMS) and recoil ion detector for DRAGON. This request is for an economical addition to DRAGON, a compact array of gamma-ray detectors, which will enhance its ability to suppress background and should provide additional information of significance both in performing the experiment and in interpreting the results.

dra_99.pdf

Author: n/a

Journal: Submitted to NSERC

The ¹³N(p,γ)¹⁴O reaction is very important for our understanding of explosive astrophysical sites, such as novae and supernovae. This reaction deter- mines the conditions under which the CNO cycle changes to the Hot CNO cycle, the main process of energy generation in such sites.

Since ¹³N is unstable, and is very close in mass to ¹³C, the DRAGON recoil mass separator at TRIUMF will firstly study the ¹³C(p,γ)¹⁴N reaction so that its properties can be compensated for when studying the ¹³N(p,γ)¹⁴O reaction.

Early analysis showed that not all the ¹⁴N recoils, from the ¹³C(p,γ)¹⁴N reaction, make it through the DRAGON to the end detector.

aaron-report.pdf

Author: Bebington, A. M.

Journal: