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Most of the experimental cross-sections present in this database have been measured in inverse kinematics at the GSI FRagment Separator (FRS). For many target materials important for EURISOL, experimental cross-section data do not exist. In those cases, a reliable prediction can nevertheless be made using ABRABLA nuclear reaction code developed at GSI. A list of publications related to cross-section measurements at the FRS, or to the development of ABRABLA code can be found here.
In order to retrieve cross-section information, the first step is to define which information are desired. Via drop-down menus in the upper panel (database options), select the reaction, cross-section type and the desired produced element.
When all of the three above mentioned options are defined, the lower panel (database results) will display which information are available for download.
This part of the database contains predictions of ISOL efficiencies for many elements and target materials relevant to EURISOL. The prediction is based on the parameterization of extraction efficiencies in function of nuclide half-lives, as proposed in [1]. The values of the parameters used in the database have been obtained by analysis of yield data from CERN-ISOLDE with 600 MeV protons [2]. One should note that these data do not reflect the performance of modern, state-of-the-art ISOL targets, or of those that will be available at EURISOL. They are rather intended to serve as a starting guideline, which allows an overview of documented ISOL efficiencies across the table of nuclides and different Target-and-Ion-Source (TIS) systems. It is our aim to update the values of efficiency parameters based on a thorough analysis of a more recent set of yield data or, eventually, a projection to the future technologies that will be available at EURISOL.
The function used to describe the dependence of efficiencies on isotopic half-lives is the following [1]:
This function was fitted to deduced efficiencies at CERN-ISOLDE [1]. The three parameters of the fit quantify the essential properties of the extraction efficiency for the element and the target – ion-source system in question:
εs - "Saturation" efficiency, i.e. value of the efficiency in the limit of long half-lives
α - Exponent characteristic of the power-function behavior of the efficiency with short half-lives
t0 - Characteristic value of half-lives where the transition from power-function to saturated behavior takes place.
The values of these parameters are retrievable for every element and TIS under "target information" (see below). The same parameters are used to calculate ISOL efficiencies isotope by isotope of the given element. These are retrievable under "efficiencies". A figure of efficiencies in function of mass-number is also available.
In order to predict efficiencies for isotopes for which half-lives have not yet been measured, theoretical predictions have been used. On the neutron-deficient side, predictions of FRDM model were used, as published by P. Möller et al. in [3]. On the neutron-rich side, the empirical parameterization of X. Zhang et al [4] was used.
To retrieve efficiency information, first define the element for which information are desired via drop-down menu in the upper panel. After that, click any of the options in the the lower panel (database results) to retrieve available information.
[1] S. Lukić et al., NIM A565 (2006) 784-800, arXiv nucl-ex/0601031
[2] H.-J.
Kluge, ISOLDE user's guide, CERN Geneva, 1986,
http://isolde.web.cern.ch/ISOLDE/
[3] P. Möller et al., Atomic Data Nucl. Data Tables 59 (1995) 185-381
[4] X. Zhang et al., J. Phys. G: Nucl. Part. Phys. 34 (2007) 2611–2632