Köln 2004 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

HK: Physik der Hadronen und Kerne

HK 43: Nuclear Structure/Spectroscopy VII

HK 43.3: Talk

Thursday, March 11, 2004, 17:30–17:45, A

Complete study of Gamow-Teller strength starting from 64Ni — •Lucia-Ana Popescu and D. De Frenne — Dep. of Subat. and Rad. Phys., Ghent University

We used the complementary reactions (d,2He) and (3He,t) on 64Ni in order to study the Gamow-Teller (GT) strength distributions in 64Co and 64Cu. The 64Ni(d,2He)64Co experiment was performed at the AGOR cyclotron of the KVI, Groningen, with Ed=170MeV, using the EuroSuperNova detector at the Big-Bite Spectrometer. An energy resolution of about 100 keV was achieved. In addition to the ground-state (gs) with J^π=1⁺, several other GT states could be identified and the strengths of them were determined. The complementary reaction 64Ni(3He,t)64Cu was performed at E3He=420MeV at RCNP, Osaka. An energy resolution of 35keV was achieved. Many GT candidate states were identified.

The isospin of the 64Ni gs is T0=4 while the isospin of the gs of 64Co and 64Cu are T=T0+1=5 and T=T0-1=3, respectively. In the (3He,t) reaction the T=3, T=4 and T=5 components of the isospin are excited. The T=5 component is very much suppressed in (3He,t) but it can be studied in detail in the (d,2He) reaction. Combining these information we can study the GT strengths starting from 64Ni in a complete manner. The gs of both 64Co and 64Cu have J^π=1⁺, making the determination of absolute B(GT) values to these states from beta-decay possible. The unit cross sections determined in these experiments provide a very important calibration standard for the fp-shell region. The analysis is in progress. Preliminary results will be presented.