Recent commissioning of the HIRFL-CSR has demonstrated its ability to perform direct mass measurement for short-lived nuclides. Projectile fragments produced by the 78Kr ions at 481.88 MeV/u were separated with the ne...Recent commissioning of the HIRFL-CSR has demonstrated its ability to perform direct mass measurement for short-lived nuclides. Projectile fragments produced by the 78Kr ions at 481.88 MeV/u were separated with the new radioactive beam line in Lanzhou (RIBLL2), and injected into and stored in the experimental storage ring (CSRe). By operating the CSRe as an isochronous mass spectrometry, a typical mass resolution around 2.0×10?5 has been achieved. The masses for 63Ge, 65As and 67Se were measured for the first time. The measured masses are compared with theoretical predictions and the location of the proton drip-line for As isotopes is discussed. The implication of the 65As mass in the astrophysical rapid proton capture process has also been addressed.展开更多
A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou...A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou is designed.The beam profile and the scattering angles on the target are deduced by two parallel plate avalanche counters,and four sets of detector telescopes(including doublesided silicon strip detectors) are placed systematically with the beam line,incorporating with Monte Carlo simulations.The data of ^(16)O on ^(89)Y target were analyzed to compare with the simulation results.It is found that the simulated distribution is agreeable with the experimental data.By assuming the pure Rutherford scattering at small scattering angles,the angular distribution of elastic scattering of^(16)O+^(89)Y at low energies can be reasonably obtained.It indicates that this set of detector setup can be used for the measurement of angular distributions of heavy-ion elastic scattering at energies around Coulomb barrier.展开更多
A velocity separator has been installed at the entrance of the Radioactive Ion Beam Line in Lanzhou (RIBLL) aiming to the experiment of fusion-evaporation reactions. It consists of 2 quadruple triplets and a perpendic...A velocity separator has been installed at the entrance of the Radioactive Ion Beam Line in Lanzhou (RIBLL) aiming to the experiment of fusion-evaporation reactions. It consists of 2 quadruple triplets and a perpendicular electric and magnetic field acting as a Wien filter. The total length of of the separator is 5. 1 m, and the designed maximum electric and magnetic fields are 15 kV/cm and 5 kG, respectively.展开更多
The experiment of measuring the differential cross sections dσ/dθat forward angles for the elastically scattered 17F (141 MeV) and 17O (128 MeV) on the 208Pb target has been carried out at the Radioactive Ion Beam L...The experiment of measuring the differential cross sections dσ/dθat forward angles for the elastically scattered 17F (141 MeV) and 17O (128 MeV) on the 208Pb target has been carried out at the Radioactive Ion Beam Line in Lanzhou (RIBLL). Fig. 1 shows the plots of In(dσ/dθ) versusθ2 for 17F (right panel) and 17O (left panel). The dependence of the ln(dσ/dθ) onθ2 shows quite different behaviors for the two nuclei. For the weakly bound nu-展开更多
基金Supported by the National Natural Science Foundation of China (Grant Nos. 10635080, 10221003, 10675147)National Basic Research Program of China (Grant Nos. 2007CB815000, 2008CB817702)Knowledge Innovation Project of Chinese Academy of Sciences (Grant No. CXTD-J2005-1, KJCX2-SW-N18)
文摘Recent commissioning of the HIRFL-CSR has demonstrated its ability to perform direct mass measurement for short-lived nuclides. Projectile fragments produced by the 78Kr ions at 481.88 MeV/u were separated with the new radioactive beam line in Lanzhou (RIBLL2), and injected into and stored in the experimental storage ring (CSRe). By operating the CSRe as an isochronous mass spectrometry, a typical mass resolution around 2.0×10?5 has been achieved. The masses for 63Ge, 65As and 67Se were measured for the first time. The measured masses are compared with theoretical predictions and the location of the proton drip-line for As isotopes is discussed. The implication of the 65As mass in the astrophysical rapid proton capture process has also been addressed.
基金Supported by the National Natural Science Foundation of China(Nos.11475013,11175011,11035007)
文摘A detector setup for the measurement of angular distribution of heavy-ion elastic scattering at energies around Coulomb barrier on the radioactive ion beam line in Lanzhou at the heavy-ion research facility in Lanzhou is designed.The beam profile and the scattering angles on the target are deduced by two parallel plate avalanche counters,and four sets of detector telescopes(including doublesided silicon strip detectors) are placed systematically with the beam line,incorporating with Monte Carlo simulations.The data of ^(16)O on ^(89)Y target were analyzed to compare with the simulation results.It is found that the simulated distribution is agreeable with the experimental data.By assuming the pure Rutherford scattering at small scattering angles,the angular distribution of elastic scattering of^(16)O+^(89)Y at low energies can be reasonably obtained.It indicates that this set of detector setup can be used for the measurement of angular distributions of heavy-ion elastic scattering at energies around Coulomb barrier.
文摘A velocity separator has been installed at the entrance of the Radioactive Ion Beam Line in Lanzhou (RIBLL) aiming to the experiment of fusion-evaporation reactions. It consists of 2 quadruple triplets and a perpendicular electric and magnetic field acting as a Wien filter. The total length of of the separator is 5. 1 m, and the designed maximum electric and magnetic fields are 15 kV/cm and 5 kG, respectively.
文摘The experiment of measuring the differential cross sections dσ/dθat forward angles for the elastically scattered 17F (141 MeV) and 17O (128 MeV) on the 208Pb target has been carried out at the Radioactive Ion Beam Line in Lanzhou (RIBLL). Fig. 1 shows the plots of In(dσ/dθ) versusθ2 for 17F (right panel) and 17O (left panel). The dependence of the ln(dσ/dθ) onθ2 shows quite different behaviors for the two nuclei. For the weakly bound nu-
