Our activity
We closely cooperate, as a part of international collaboration FULIS with the laboratories: Ganil and LPC-Caen. We take part, from many years, in experiments conducted there.
During that time the FULIS collaboration have conducted several experiments such as: 86Kr+208Pb → 294118, at the beam energy E=5.270 MeV/u, 54Cr+208Pb → 262106, E=4.698 and 4.756 MeV/u, and in the fall of 2003 58Fe+208Pb → 266108, E=4.920, 4.870 and 4.82 MeV/u and 76Ge+208Pb → 284114, E=4.90 MeV/u. In the measurements aimed at synthesis of elements 106 (Sg) and 108 (Hs) we have found 12 and 7 events correspondingly which confirms the production of these nuclei. For the isotope of the element Z=108 this gives around 10% of all documented events so far. In reaction with Ge beam, attempt to make synthesis of Z=114, we have found one interesting event. Further analysis is needed, especially background and random coincidences have to be considered, to confirm or not the synthesis of that element in this reaction. It is also worth to mention the inverse kinematics experiments: 208Pb+18O,12C. In such a case projectile is heavier then the target nucleus, Zp>Zt. As a consequence the fusion products have much higher kinetic energy then in the analogous reaction made in normal kinematics. So it was possible to modify detection setup working at GANIL and install additional detector. This was ionization chamber which was build in Kraków [Wie04] (some photos of the detector one can find here). Results of these experiments were presented at international conferences and in the form of publications [Pet1_01], [Pet2_01], [Gre02], [Wie04].
Our goal is to further modify SHE detection system working at GANIL by constructing gaseous detector which will use inter alia gas scintillation. We plan also to build low noise electronics dedicated for such detector. The second goal is to modify fast analysis software, prepared by our group, which was used in many many experiments to search on-line for alpha chains.
Our group is experienced in detector construction and associated electronics building. In the last years in the Hot Matter Physics Department (HMPD) we have build several gas detectors which were used in many experiments. Among them are: gas detector generating signal which is the convolution of the Bragg curve and a given partition function, multi-anode gas detector or ionization chamber [Sos84], [Sos94], [Ada03], [Wie04]. Information on electronics which we have build in HMPD can be found in [Loj03], [Ada03].
Obtained results will be presented on conferences and published as a paper. They will be also the basis for the PhD theses of the project members.
Steps in the project:
- Building multi-plane gas detector. By charge collection detector will determine position and energy loss of the passing particles. Using scintillation in gas, fast time signal will be generated. 24 low noise preamplifier and electronics for photomultiplier will be build.
- In next stage we plan to construct 24-channel spectroscopic amplifier.
- Software monitoring the detector will be written and we will modify acquisition program for on-line alpha chains identification.
- the test measurements will be done on the available accelerators.
- As a last step we will install the detector in the GANIL detection system which is used for years to study super-heavy elements production.
Andrzej Wieloch