Home/To the Main Page Search/Search E-Mail

December 2018

20.12.2018 - FLNR CAP Scientific Seminar "Exploration of REciprocity in the STopping of slow ions in matter with computer code REST", 15-00, Flerov Lab Conference Hall.
Speakers: V.Kuzmin, FLNR, JINR

The principle of reciprocity in the electronic stopping of slow ions in matter gives researchers a clear and powerful criterion for testing of reliability of experimental data as well as stopping theories and models. Moreover, the principle allows to determine missing stopping cross section S(Y-> X) upon condition a credible S(X -> Y) is available.
A computer code REST has been developed to facilitate a cumbersome compilation, analysis and visualization of data from various data sets. This work presents a new extended version of the code.

Improvements include:
  • all elements of Paul's database can be analyzed;
  • classic theories by Lindhard & Scharff and by Firsov are implemented;
  • PASS stopping database can be examined;
  • user's database can be appended to Paul's one;
  • the code provides a statistical analysis of available data;
  • up to four additional data sets can be included into plots;
  • the current version of REST utilizes dynamically allocated objects to reduce computer memory usage.

18.12.2018 - FLNR Scientific Seminar "Towards limits of existence of nuclear spieces with EXPERTs", 15-30, Flerov Lab Conference Hall.
Speakers: I.Mukha, O.Kiselev, Helmholzzentrum GSI, Darmstadt

Experimental advances in nuclear spectroscopy beyond the proton dripline with the EXPERT setup (EXotic Particle Emission and Radioactivity by Tracking) will be presented.

(I) Phenomena observed in extremely neutron-deficient quasi-stationary isotopes of argon and chlorine elements will be reported by I.Mukha. The experiment, where spectroscopy of five previously-unobserved proton-unbound isotopes, 28,29,30Cl and 29,30Ar could be achieved, was performed at the FRS fragment separator by using the state-of-the-art tracking technique applied to all reaction products. The newly-observed systematic trends allow for predictions of even lighter systems, located three mass units further away from the dripline, where 26Ar and 25Cl are expected to form the lightest possible isotopes of these chemical elements. With dominating sd-shell configurations, the ground states of these nuclei are close to the transition to the continuum, their lifetimes become shorter than single-orbit times of the nucleons, and thus the well-ordered nuclear structure starts to dissolve: the end of the nuclear map and the transition to chaotic nucleon matter is expected.

(II) The EXPERT members (dominated by the ACCULINNA and FRS teams) work on gripping such a transition in experiments at the Super-FRS separator of the FAIR project. The dedicated detectors of charged particles, neutrons and gamma rays are being developed and tested at FRS and ACCULINNA. Current status of the EXPERT instrumentation will be reviewed by O.Kiselev.

14.12.2018 - FLNR Scientific Seminar "Clusterization, crystalization and exotism of nuclei (goals, tasks and expected results)", 11-00, Flerov Lab Conference Hall.
Speaker: Yushkov A.V., LNVRB, Kazakhstan

13.12.2018 - FLNR Scientific Seminar "Status of RAON and its Experimental Systems", 11-00, Flerov Lab Conference Hall.
Speaker: Seung-Woo Hong, RAON User Liaison Center & Sungkyunkwan University

The Institute for Basic Science (IBS), located in Daejeon, Korea, was established in 2011 by the Korean government. IBS has 28 Research Centers, one of which is the Rare Isotope Science Project (RISP). The accelerator complex for RISP was named RAON, which is a Korean word meaning "joy" or "happiness". The goal of RISP is to produce a variety of stable and rare isotope beams which can be used in a variety of basic scientific research and applications. The RAON can deliver ions from protons to uranium. Proton and Uranium beams are accelerated up to 600 MeV and 200 MeV/u, respectively. The RAON will produce isotopes by using both In-Flight (IF) fragmentation and Isotope Separation On-Line (ISOL) methods. The IF system uses a driver linac which consists of superconducting ECR ion sources, a low energy beam transport (LEBT) section, a 300 keV/u RFQ, a superconducting (SC) linac, a medium energy beam transport (MEBT) section for a 400 kW in-flight fragmentation facility. The ISOL system uses a proton cyclotron as a driver, which accelerates protons to 70 MeV at 1 mA for ISOL facility. The ISOL facility uses a SC linac for post-acceleration of rare isotopes up to about 18.5 MeV/u, while the SC linac of IF facility is capable of accelerating uranium beams up to 200 MeV/u at 8 pμA.

There are seven experimental systems that are under construction, which include KOBRA, LAMPS, MMS, CLS, muSR, NDPS and BIS. The RAON User Liaison Center is established to facilitate the communication between the RISP and the outside users who will use the seven experimental systems. There is also an organization called the "RAON User Association" for promoting the use of the RAON among the users. We welcome participation of international users to the RAON User Association and the RAON User Liaison Center. The presentation will discuss the present status of RAON and it experimental systems and would like to promote international collaboration.

  • Last month seminars