Abrasion -Fission

The code operates under MS Windows environment and provides a highly user-friendly interface. It can be freely downloaded from the following internet addresses:

http://www.nscl.msu/edu/lisehttp://dnr080.jinr.ru/lise

Application The program has been developed to calculate the transmission and yields of fragments and fusion residues produced and collected in a spectrometer. LISE++ is the new generation of the LISE code, which allows the creation of a spectrometer through the use of different blocks. A block can be a dipole (dispersive block), a material, a piece of beampipe, etc.

The LISE code may be applied at low-energy, medium-energy and high-energy facilities (fragment- and recoil-separators with electrostatic and/or magnetic selections). A number of these facilities like A1900 and S800 at NSCL, RIPS at RIKEN, LISE and SPEG at GANIL, FRS at GSI, COMBAS and ACCULINA at Dubna, based on the separation of projectile-like fragments are included or might be easily added to the existing optical configuration files.

Chart1

40

13

9

8

6

3

3

18

The LISE code geography

Japan13%

USA40%

Germany9%

other17%

Geography

USA40

Japan13

Germany9

Russia8

France6

China3

Italy3

Other18

100

USA39.92%413940

Japan13.03%135113

Germany9.17%9519

Russia8.46%8778

France5.53%5736

China3.40%3523

Italy3.09%3203

Other17.40%180418

Grand Total100.00%10367100

Geography

The LISE code geography

other17%

Germany9%

USA40%

Japan13%

Main featuresFast analytical calculationsReaction mechanisms projectile fragmentation, fusion-evaporation, Coulomb fission, Abrasion-Fission Highly userfriendly environmentOptics ( Transport matrices are used)Ion charge state distribution calculations (4 methods)Range and energy loss in material calculations (4 methods)Contribution of secondary reactions in the targetDifferent selection methods (Brho, Wedge, velocity, Erho)In-built help supportIn-built powerful tools

In action

In-Flight Fission In the development of the fission mechanism in the LISE++ framework it is possible to distinguish the following principal directions: * Production cross-section of fragments* Kinematics of reaction products* Spectrometer tuning to the fragment of interest to produce maximal rate (or purification)High-energy secondary-beam facilities such as RIA, RIBF and GSI provide the technical equipment for a new kind of fission experiment. We need fast predictions of fission fragment intensities.A new model of fast analytical calculation of fission fragment transmission through a fragment separator has been developed in the framework of the LISE++ code.

Coulomb FissionDeexcitation channels for 238U nuclei at 600 MeV/u excited by a lead target. The solid red curve represents fission decay. The blue dashed line represents 1n-decay channel, black dotted and green dot-dashed curves respectively 2n- and 3n-decay channels.

Abrasion-Fission

Abrasion-Fission

Abrasion-Fission: what is solution?

Fission excitation function

Three-excitation-energy-region modelPartial and total mass distributions of Strontium fission fragments in the reaction 238U(80MeV/u)+Be.

Total fission cross-sections of 238U at relativistic energies Total fission cross-sections of 238U at energies between 0.6 and 1 GeV per nucleon. See inset in the figure for details. LISE calculations were done for two prefragment excitation energy values. 13.3 and 27 MeV/dA.

238U(1AGeV) + PbT.Enqvist et al., Nucl.Phys. A658 (1999) 47-66

238U(1AGeV) + pM.Bernas et al, Nucl.Phys. A725 (2003) 213-253

238U(1AGeV) + pMeasured and LISE calculated fission-fragment mean kinetic energies as a function of their proton for the data [Ber03] (238U(1AGeV)+p).

208Pb(1AGeV) + pT.Enqvist et al., Nucl.Phys. A686 (2001) 481-524.

208Pb(1AGeV) + dT.Enqvist et al., Nucl.Phys. A703 (2002) 435-465

KinematicsSelectionLISE++ MCmethodLISE++ DistrMethodAfter target After dipole238U(920AMeV)+Pb(5g/cm2)->100ZrTwo different methods for fission fragment kinematics are available in LISE++: MCmethod and DistrMethod. DistrMethod is the fast analytical method applied to calculate the fragment transmission through all optical blocks of the spectrometer. MCmethod (Monte Carlo) has been developed for a qualitative analysis of fission fragment kinematics and utilized in the Kinematics calculator.

Selection132Sn fragment energy distribution after the second dipole obtained in the reaction 238U(80MeV/u)+Be(80mg/cm2). Two dimensional identification plot for fission fragments using an achromatic Be-wedge (60mg/cm2). 81Zn is selected by a red contour. Two dimensional identification plot for fission fragments without a wedge. Zinc isotopes are selected by a red contour.

Secondary Reactions, Optimum targetIncludes the reaction coefficient of losses and the secondary reactions contribution coefficientOptimal target thickness of Tin isotopes produced in the fission of 238U(1AGeV, 1pnA) on a Be-target taking into account secondary reactions contributions.

SummaryWelcome to the LISE site to see details!Register in LISEs sites to get information about new versions of the code http://www.nscl.msu.edu/lise or http://dnr080.jinr.ru/lise

The authors thank for the help in developing Coulomb fission model in the program:

Matthew Amthor (NSCL/MSU)Brad Sherrill (NSCL/MSU) Michael Thoennessen (NSCL/MSU)Jorge Pereira Conca (NSCL/MSU)Marc Hausmann (NSCL/MSU)Helmut Weick (GSI) and DOE #DE-FG03-03ER41265 grantNSF #PHY-01-10253 grant A new model of fast analytical calculation of fission fragment transmission* through a fragment separator has been developed in the framework of the LISE++ code.

The LISE++ program has become an important tool for the planning experiments at different laboratories around the world (RIBF,RIA,GSI).

Next steps: secondary reactions in wedge, secondary target, RF-kicker, Monte Carlo transmission.

* kinematics of fission products, production cross-section of fragments (Abrasion-Fission & Coulomb fission), spectrometer tuning