Contact
Special Seminars 2008
| Time: | Monday, 6. October 2008, 16.00 h c.t. |
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| Place: | Seminar room Blaum |
| Speaker: | Dr. Yoshitaka Fujita, Department of Physics, Osaka University, Japan |
| Title: | Study of far-stability nuclei by combining mirror Gamow-Teller transitions |
Abstract
Gamow-Teller (GT) transition is one of the most popular nuclear weak processes of
spinisospin (στ) type. It is of interest not only in the study of nuclear physics, but
also in astrophysics; it plays important roles, for example, in supernova-explosion
or nuclear synthesis. Relatively limited information can directly be obtained through
the study of weak processes, such as β decay or neutrino induced reactions. However,
it was found that (p, n) charge-exchange reactions at intermediate incoming energies
(E > 100 MeV) and at 0° could selectively excite GT transitions, that extended the
region of excitation energy of the study. With one-order-of-magnitude improvement of
the energy resolution in (3He,t) measurements at 140 MeV/nucleon, fine structures
of GT excitations, even those of GT giant resonances, can now be studied. Determination
of GT transition strengths for pf-shell nuclei with astrophysical interest is
discussed [1]. We show that quantum number "isospin" and accurate Q values (masses)
of proton-rich nuclei play important roles in such studies.
[1] Y. Fujita et al., Phys. Rev. Lett. 95 (2005) 212501 
| Time: | Tuesday, 23. Sept. 2008, 16.00 h c.t. |
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| Place: | Seminar room Blaum |
| Speaker: | Dr. Joseph Formaggio, Massachussetts Institute of Technology, Cambridge/MA, USA |
| Title: | Twilight: Results from the third final phase of SNO |
Abstract
The Sudbury Neutrino Observatory (SNO) has the ability to measure the total flux of all active flavors of neutrinos using the neutral current reaction, whose signature is a neutron. By comparing the rates of the neutral current reaction to the charged current reaction, which only detects electron neutrinos, one can test the neutrino oscillation hypothesis independent of solar models. This talk will present results from the third and final phase of the SNO experiment.