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STUDIA UNIVERSITATIS BABEŞ-BOLYAI, PHYSICA, SPECIAL ISSUE, 2001 DATA EVALUATION LINKING BASIC AND APPLIED RESEARCH AMONG EUROPEAN CENTERS OF EXCELLENCE* VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU “Horia Hulubei” National Institute for Physics and Nuclear Engineering (IFIN-HH), P.O. Box MG-6, 76900 Bucharest, Romania ABSTRACT. Review of the atomic and nuclear data evaluation at IFIN-HH is carried out along with research priorities of European Commission (EC) Fifth Framework Programme (FP5). Integration of basic research and objectives of nuclear safety and environmental protection is thus ensured as well that of scientists from Central and Eastern Europe (CEE) into the EC research programmes, e.g. EURATOM and EC Joint Research Center (JRC) projects. Recent experience of IFIN-HH receiving EC/FP5 Support for CEE Centres of Excellence, is discussed with the aim of further increase of the above-mentioned integration. 1. Introduction The objective of consolidation of the scientific basis for, e.g., atomic and nuclear data is a research priority of the EURATOM/Fifth Framework Programme (FP5). Thus, advanced low-activation and radiation-resistant materials, as well as the precise definition of a reference material with reduced activation are main lines of FP5 Key Actions. However, since it is costly and virtually impossible to measure all atomic and nuclear data required by these applications, the development of the corresponding computing methods are essential. On the other hand, specific experimental data do not impose sufficient constraints on the theoretical nuclear reaction models. Most of them could be equally well reproduced in terms of different approaches by adjustment of parameters always involved even in the "parameter free" models. In order to increase the predictable power of model calculations, compensation of opposite effects due to various less accurate parameter values can be avoided by means of1: (a) unitary use of common model parameters for different mechanisms, (b) use of consistent sets of input parameters determined by various independent data analysis, and (c) unitary account of a whole body of related experimental for isotope chains of neighboring elements. Improved nuclear model calculation methods for nuclear activation data have been carried out at IFIN-HH by using the exciton and the Geometry-Dependent Hybrid (GDH) semi-classical models for the pre-equilibrium emission (PE) and Hauser*Lecture 1 at The 2-nd Conference on Isotopic and Molecular Processes, Cluj-Napoca, September 2729, 2001. Work supported in part under the MEC Grant No. 1366/2001. M. Avrigeanu, M. Ivascu, and V. Avrigeanu, Z. Phys. A 329 , 177 (1988); ibid. 335, 299 (1990); Atomkernenergie-Kerntechnik 49, 133 (1987) VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU Feshbach statistical model within the computer code STAPRE-H952. Since PE models have been recently proved3 not able to reproduce the decrease of the (n,p) reaction excitation function in the energy range above the common 15 MeV value, additional work has had to be devoted to this objective. Further advance is possible by the development in the meantime within IFIN-HH of the novel partial level-density formalism4 of the recent IAEA Reference Input Parameter Library (RIPL)5 as well as an improved version of the corresponding computer code PLD6. It should be noted that the statistical-model parameters are involved beyond the reaction cross-section calculations also in various studies of nuclear phenomena from, e.g., elastic scattering to cold fission, which may be used for their analysis too7,8. Moreover, since completion of the EURATOM-FUSION objectives has recently requested nuclear-data evaluation for D incident on 6,7Li, for D energies up to 50 MeV, we have analyzed the possibility to work on it at IFIN-HH. The previous IFIN-HH results concerning both the realistic effective nucleon-nucleon (NN) interaction9 and the use of the double-folding (DF) model for microscopic optical-potential calculation10,11 may be helpful in this respect. We have thus looked for the integration of basic research and objectives of nuclear safety and environmental protection within the EC research programmes such as EURATOM and EC Joint Research Center (JRC). A fruitful cooperation is established in this respect between IFIN-HH and the EC/JRC Institute for Reference Materials and Measurements (IRMM) based on previous IFIN results3,4,6-9, our group working now under the following projects: Association EURATOM - NASTI-Romania (2000-2002), EC/JRC/IRMM project “Neutron Data Measurement and Evaluation Activities”, (two senior scientists and two open positions as PhD-student), and EC/FP5/INCO2 Support for Centres of Excellence under Contract ICA1CT-2000-70023 with IFIN-HH. The last action was initiated and largely guided by EC/JRC/IRMM-Geel, leading finally to the only one successful atomic-physics proposal from EEC under the corresponding FP5 call. Basic points of our group contributions to these projects are given in the following. 2 M. Avrigeanu and V. Avrigeanu, STAPRE-H95 Computer Code, IPNE Report NP-86, Bucharest,1995; in E. Sartori (Ed.), Nuclear Model Codes, OECD NEA Data Bank, Saclay, 1992, p. 102; News NEA Data Bank 17 (1995) 22, 25. 3 A. Fessler, E. Wattecamps, D.L. Smith, and S.M. Qaim, Phys. Rev. C 58, 996 (1998). 4 A. Harangozo, I. Stetcu, M. Avrigeanu, and V. Avrigeanu, Phys. Rev. C 58, 295 (1998). 5 P. Oblozinsky, "Development of Reference Input Parameter Library (RIPL) for Nuclear Model Calculations of Nuclear Data", Report INDC(NDS)-335, IAEA, Vienna, 1995; Report IAEATECDOC-1034, IAEA, Vienna, 1998 [ http://www-nds.iaea.or.at/ripl/ ]. 6 M. Avrigeanu and V. Avrigeanu, Comp. Phys. Comm. 112, 191 (1998). 7 V. Avrigeanu, P.E. Hodgson, and M. Avrigeanu., Phys. Rev. C 49, 2136 (1994). 8 V. Avrigeanu, A. Florescu, A. Sandulescu, and W. Greiner, Phys. Rev. C 52, R1765 (1995). 9 M. Avrigeanu et al., Phys. Rev. C 54, 2538 (1996); ibid. 56, 1633 (1997). 10 M. Avrigeanu, G.S. Anagnostatos, A.N. Antonov, J. Giapitzakis, Phys. Rev. C 62, 017001 (2000). 11 M. Avrigeanu, A.N. Antonov, H. Lenske, and I. Stetcu, Nucl. Phys. A693, 616 (2001). 102 DATA EVALUATION LINKING BASIC AND APPLIED RESEARCH AMONG EUROPEAN CENTERS … 2. Double-folding method for calculation of nuclear potential In order to establish the correctness of various assumptions considered within the DF method11 for the few-nucleon systems, the large density effects on the elastic scattering of 6,8He on 4He within microscopic optical potential have been analyzed. The comparative analysis of the experimental and microscopic elastic scattering angular distributions of 6,8He on 4He has been carried out. The calculated angular distributions have been obtained employing a microscopic real optical potential based on (a) Tanihata and COSMA models (see11 for references) for the density distributions of Helium isotopes (Fig. 1), and (b) the M3Y, BDM3Y, and DDM3Y Paris effective NN interactions (Fig. 2). The sensitivity of the calculated cross sections with respect to both density distributions and effective NN interactions have been analyzed on this basis. 4 4 He -3 10 Tanihata COSMA -7 He -2 10 -4 (d) 6 He -2 10 -4 10 8 (b) ] -11 10 10 -3 -3 ] (a) 6 10 -7 10 n(r) [fm ] -3 (r) [fm -11 10 He -3 10 (e) -11 10 p(r) [fm -7 10 4 He -3 10 6 -6 10 -9 He He He -3 10 10 8 (c) (f) 8 He -3 10 -2 -2 10 10 -6 10 -4 10 0 (g) -4 2 4 6 10 0 (h) -9 2 4 6 10 0 (i) 2 4 6 r [fm] Fig. 1. Neutron and proton density distributions for 4,6,8He nuclei by Tanihata and COSMA models. Finally, it results that Tanihata's density distributions and the density dependent DDM3Y Paris effective NN interaction led to better agreement with the experimental data (Fig. 3). Based on these results it becomes possible the use of DF method for calculation of the nuclear potential for complex particles (e.g. 2,3H, 3,4He) emitted in fast-neutron induced reactions on medium nuclei, as well as for evaluation of the nuclear data for D incident on 6,7Li. 103 VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU 100 6 80 4 He+ He COSMA density Einc=151 MeV 60 Bachelier'72 M3Y BDM3Y DDM3Y Tanihata density 40 -UR(r) [MeV] 20 0 0 120 (b) (a) 2 4 8 100 6 0 2 4 He+ He COSMA density 80 Einc=211 MeV 60 Tanihata density M3Y BDM3Y DDM3Y 40 20 0 0 6 4 (d) (c) 2 4 6 0 2 4 6 r [fm] Fig. 2. Comparative analysis of the microscopic real optical potentials, for 6,8He scattered on 4He calculated with Tanihata and COSMA densities, and M3Y, BDM3Y, DDM3Y effective NN interactions. 2 6 0 Einc=151 MeV 10 10 -2 Tanihata 10 d / d [mb/sr] -4 10 -6 10 0 4 He+ He (a) Oganessian'99 Bachelier'72 M3Y BDM3Y DDM3Y 30 60 COSMA density (b) 90 120 150 0 30 60 90 120 150 180 3 10 8 4 He+ He Einc=211 MeV 1 10 Tanihata -1 10 -3 10 0 (c) Oganessian'00 M3Y BDM3Y DDM3Y 30 60 COSMA density (d) 90 0 30 60 90 120 c.m. [deg] Fig. 3. Comparison of the elastic scattering differential cross sections of 6,8He on 4He, calculated with Tanihata and COSMA parametrization and with M3Y, BDM3Y and DDM3Y-Paris effective NN interaction, and the experimental data of Oganessian et al. (1999). 104 DATA EVALUATION LINKING BASIC AND APPLIED RESEARCH AMONG EUROPEAN CENTERS … 3. Improved model calculation of nuclear activation data In the frame of the cooperation between IFIN-HH (Bucharest) and EC/JRC/IRMM (Geel) it was carried out recently the analysis of new IRMM accurate measurements, being established12 that an improper consideration of the normalization method was involved by all recent international evaluated nuclear-data files in the case of the reaction 51V(n,n’)47Sc. Work on new evaluated file for fast-neutron reactions on vanadium, of further interest for EAF-99 become thus necessary. Next, during the Workshop on Activation Data – EAF-2001 (6-7 Nov. 2000, CE de Cadarache) it was stated that extension of the model calculations, requested by the development of the next library version EAF-2003, is conditioned by their validation in various mass regions. It is why the above-mentioned consistent model calculations have been carried on also for the Mo isotopes. The first step of this work has been the study of the activation cross sections for reactions induced on 92Mo, namely, 92Mo(n,p)92Nbm, 92Mo(n,)89Zrg,m, 92Mo(n,2n)91Mog,m, and 92Mo(n,n’p)91Nbm, for which there is also a large amount of measured data. However, there are yet many discrepancies between even recent data sets, while three basic evaluations performed in the last decade at well-known laboratories show wide differences, e.g. up to ~50% for the (n,p) reaction13,14 and ~65% for the (n,) reaction13,15. In order to obtain confident calculated cross sections under these conditions, we have had to enlarge the parameter analysis carried out already in this respect concerning the following quantities which are most important for calculation of the isomeric cross section ratios: 3.1. Ratio between the nuclear moment of inertia I - the third parameter of the backshifted Fermi gas (BSFG) model for the nuclear level density - and the rigid-body value Ir has been obtained16 by using the method of Weigmann17 et al. and the corresponding recent experimental neutron and proton-resonance spacings (RIPL), as shown in Fig. 4. (E*,J) (Levels/MeV) 3 10 51 51 V V 2 10 * * E =10.646 MeV E =10.646 MeV 1 10 Vonach+ (1988) RIPL (1998) 0 10 Vonach+ (1988) RIPL (1998) (b) (a) 0 3 6 9 12 0 3 6 9 12 15 J (h) Fig. 4. Comparison16 of the spin-dependent level densities of the nucleus 51V. 12 P. Reimer, V. Avrigeanu, A.J.M. Plompen, and S.M. Qaim, Phys. Rev. C (in press). S.M. Qaim, R. Wolfle, and B. Strohmaier, Phys. Rev. C 40, 1993 (1989). 14 P.E. Garret, L.A. Bernstein, J.A. Baker, K. Hauschild, C.A. McGrath, D.P. McNabb, W. Younes, M.B. Chadwick et al, Phys. Rev. C 62, 054608 (2000). 15 N. Yamamuro, Nucl. Sci. Eng. 109, 128 (1991). 16 V. Avrigeau, T. Glodariu, A.J.M. Plompen, H. Weigmann, J. Nucl. Sci. Eng. (to be published). 17 H. Weigmann, C. Wagemans, A. Emsallem, and M. Asghar, Nucl. Phys. A368, 117 (1981). 13 105 VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU 3.2. The analysis of the nuclear-level density parameters a and of the back-shifted Fermi gas (BSFG) model was carried out for 70 isotopes in the atomic-mass range A=79-111. The fit of the most recent experimental low-lying discrete levels (ENSDF file on the BNL-Brookhaven web site) and the s-wave nucleon resonance spacings (the corresponding RIPL file on the NDS/IAEA-Vienna web site) was done in this respect, corresponding to the values 0.5, 0.75, and 1 for the ratio I/Ir (Fig. 5). 16 * BSFG: I/Ir=0.5-0.75 (E =0-Bn) * BSFG: I/Ir=0.5-0.75 (E =0-8 MeV) BSFG: I/Ir=0.5 14 10 a (MeV even-even even-odd odd-even odd-odd even-even even-odd odd-even odd-odd -1 ) 12 8 BSFG: I/Ir=1 BSFG: I/Ir=0.75 14 12 10 8 even-even even-odd odd-even odd-odd 80 90 100 even-even even-odd odd-even odd-odd 110 80 90 100 110 A Fig. 5. Values of the level-density parameter a obtained by fit of the ENSDF and RIPL data 3.3. The BSFG model has been used for the nuclear level density at excitation energies lower than 12 MeV, which is the excitation region in which the corresponding parameters are obtained by fit of experimental data. At higher excitation it has been adopted the realistic analytical formula of Schmidt et al.18. This approach has been revised on the basis of all available data for the level density at excitation energies above the binding energy16 (Fig. 6). 3.4. The optical model potential (OMP) for calculation of proton transmission coefficients on the residual nucleus 92Nb, for energies up to 20 MeV, has been established through the analysis of the available 93Nb(p,n)93Mo reaction cross sections up to Ep=5.5 MeV, and total proton reaction cross sections around Ep=10 MeV (Fig. 7). 3.5. The systematics of the correction factor of the -ray strength functions shown in Fig. 8(a), used for the -ray transmission coefficients calculation in the framework of a modified energy-dependent Breit-Wigner model, has been established by analyzing the RIPL average radiative widths of the s-wave neutron resonance. At the same time the -ray decay schemes have been considered most carefully as shown, e.g., in Fig. 8(b). 18 K.-H. Schmidt, H. Delagrange, J.P. Dufour, N. Carjan, and A. Fleury, Z. Phys. A 308, 215 (1982). 106 DATA EVALUATION LINKING BASIC AND APPLIED RESEARCH AMONG EUROPEAN CENTERS … 55 10 56 Mn 6 Fe Bn=10.227 MeV Bp+Ep/2=10.500 MeV Bn=11.198 MeV =1.60 MeV W'95=0.05 MeV p 10 4 10 2 10 0 10 6 D0 =7.1 +- 7 keV =0 MeV W'95=0.68 MeV B RO1; Ir RO12; Ir/2 ROevap; evap.spec. DENS(5.40/0.75/-0.30) DENS(a=6.222)/KC:dW=-0.78 (n(B): 0.668) DENS(11.2-15 MeV) DN RO DENS (5.50/0.75/-1.92: D 0=6.43) DENS (a=6.111)/KC:dW=-0.19 (n(B): 0.672) DENS (10.2-15 MeV) 57 60 Co Ni Bn=11.376 MeV Bp+Ep/2=8.82 / 9.591 MeV Bn=11.389 MeV =1.549 MeV p Levels/MeV D0 =19.4+-2.4 / 13.3+-1.1 KeV =0 MeV 10 4 10 2 10 0 10 8 10 6 10 4 10 2 10 0 W'95=-0.16 MeV W'95=-0.89 MeV B B B B DENS(5.80/0.75/-1.15) DENS(a=6.333)/KC: dW=-1.16 (n(B): 0.747) DENS(11.4-15 MeV) DN RO1; Ir RO1.2; Ir/2 DENS(6.10/0.75/0.05) DENS(a=6.667)/KC: dW=-0.26 (n(B): 0.704) DENS(11.4-15 MeV) 70 69 Ge As 10 Bn=12.270 MeV =0 MeV Bn=11.536 MeV =1.435 MeV W'95=3.76 MeV W'95=4.13 MeV B B DENS (9.80/0.75/1.00) DENS (a=7.778)/KC: dW=5.54 (n(B): 0.753) DENS (11.5-15 MeV) B B DENS (9.25/0.75/-0.70) DENS (a=7.667)/KC: dW=5.17 (n(B): 0.762) DENS (12.3-15 MeV) 104 10 8 10 6 10 4 10 2 10 0 114 Pd 10 Sn Bn=10.014 MeV =1.177 MeV Bn=10.300 MeV =1.124 MeV W'95=1.83 MeV W'95=1.83 MeV B B DENS (13.25/0.75/0.60) DENS (a=11.556)/KC: dW=5.00 (n(B): 0.769) DENS (10-15 MeV) 0 5 10 15 20 B B DENS (13.50/0.75/1.30) DENS (a=12.667)/KC: dW=1.46 (n(B): 0.865) DENS (10.2-15 MeV) 0 5 10 15 20 25 E*(MeV) Fig. 6. Experimental and calculated observable total level densities 16. -1 0.8 10 93 93 Nb(p,n) Mo 93 -2 p + Nb 0.6 -3 10 Johnson+ (1979) Johnson+ (1979) Perey (1963) BG (1969) Modified OMP (a) -4 10 -5 10 2 3 4 Ep (MeV) 5 R (b) (b) 10 0.4 Carlson (1996) Johnson+ (1979) Perey (1963) BG (1969) Modified OMP (b) 0.2 0.0 6 7 8 9 10 Ep (MeV) Fig. 7. Comparison of experimental and calculated (p,n) and proton total reaction cross sections19. 107 VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU 1.0 2.5 Obninsk: e-e Obninsk: odd-A Obninsk: o-o 92 2.0 E (MeV) 0.8 1.5 * FSR 0.6 Nb 0.4 0.2 1.0 0.5 0.0 100 Beijing: e-e Beijing: odd-A Beijing: o-o (a) 80 90 (b) 0.0 100 0 92 Nb 31 m 2 4 6 8 J (h) A Fig. 8.(a) Systematics of the EDBW -ray strength functions, and (b) -ray decay scheme of 92Nb. Finally, the calculated19 excitation functions for activation reactions 92Mo(n,)89Zrg,m, 92Mo(n,2n)91Mog,m, and 92Mo(n,n’p)91Nbm are shown in Figs. 9-11. 92Mo(n,p)92Nbm, 0.12 92 92 m Mo(n,p) Nb 0.10 -1 10 + (2 ) 92 Kanda (1972) Rahman+ (1985) Marcinkovski+ (1986) Ikeda+ (1988) Kobayashi+ (1988) Liskien+ (1989) Kimura+ (1990) Qaim+ (1993) Kong+ (1995) Molla+ (1986,1997) Debrecen (1998) Filatenkov+ (1999) STAPRE-H (2001) 0.06 0.04 0.02 0.00 91 m Mo(n,n'p) Nb -2 10 - (1/2 ) (b) (b) 0.08 -3 10 Greenwood+ (1987) Liskien+ (1989) Qaim+ (1993) STAPRE-H (2001) -4 10 -5 6 8 10 12 14 16 18 10 20 8 10 12 En (MeV) 14 16 18 20 En (MeV) Fig. 9. Comparison19 of experimental and calculated (n,p) and (n,n’p) cross sections of 92Mo. 92 0.08 91 92 Mo(n,2n) Mo 91 92 m Mo(n,2n) Mo ( 1/2 ) 0.8 0.4 0.2 0.0 12 14 16 18 En (MeV) 20 Minetti+ (1968) Lu+ (1970) Qaim (1971) Kanda (1972) Hasan+ (1972) Sigg+(1975) Fujino+ (1977) Rao+ (1979) Amemiya+ (1982) Marcinkowsi+ (1986) Ikeda+ (1988) Bostan+ (1996) Filatenkov+ (1999) STAPRE-H (2001) 0.04 0.02 0.00 0.15 - (b) Brolley+ (1952) Minetti+ (1968) Abboud+ (1969) Qaim (1971) Hasan+ (1972) Kanda+ (1972) Maslov+ (1972) Bormann+ (1976) Rao+ (1979) Pepelnik+ (1985) STAPRE-H (2001) (b) + 0.06 0.6 91 Mo(n,2n) Mo 0.20 - m(1/2 )/g(9/2 ) 1.0 Brolley+ (1952) Prasad+ (1967) Curzio (1968) Karolyi+ (1968) Abboud (1969) Qaim (1971) Kanda (1972) Habbani+ (1997) STAPRE-H (2001) 0.10 0.05 0.00 13 14 15 16 17 13 14 15 En (MeV) 16 17 18 En (MeV) Fig. 10. Comparison19 of experimental and calculated (n,2n) reaction cross sections of 92Mo. 19 M. Avrigeanu, V. Avrigeanu, and A.J.M. Plompen, J. Nucl. Sci. Eng. (to be published). 108 19 DATA EVALUATION LINKING BASIC AND APPLIED RESEARCH AMONG EUROPEAN CENTERS … The agreement between calculated and the available experimental data could be considered good in the limit of experimental errors. It is thus proved the GDH specific account of the nuclear-density distribution. Moreover, one of the main assumptions of the model is intra-nuclear transition rate based on average imaginary OMP, so that no free parameter comes in and the corresponding results become more confident. 0.60 0.012 Mo(n,) Zr 89 m 92 - ( 1/2 ) Lu+ (1970) Hasan+ (1972) Kanda (1972) Sigg+ (1975) Fujino+ (1977) Rao+ (1979) Anemiya+ (1982) Marcinkowski+ (1985) Ikeda+ (1988) Filatenko+ (1999) STAPRE-H(2001) 0.006 0.004 92 0.01 0.00 6 8 10 12 Mo(n,) Zr 14 16 18 20 0.30 Kanda (1972) Filatenko+ (1999 STAPRE-H (2001) 0.15 89 En (MeV) 89 + 0.008 Mo(n,) Zr 0.45 - 0.02 92 0.010 m(1/2 )/g(9/2 ) (b) 0.03 Kanda (1972) Qaim (1974) Fujino+ (1977) Rao+ (1979) Garuska+ (1980) Artemev+ (1980) Anemiya+ (1982) Pepelnik+ (1985) Marcinkowski+ (1985) Ikeda+ (1988) Liskien+ (1989) Kong+ (1991) Molla+ (1986,1997) Debrecen (1998) Filatenko+ (1999) Haight+ (1981) STAPRE-H (b) 0.04 0.002 0.000 6 8 10 12 14 16 18 20 En (MeV) 0.00 6 8 10 12 14 16 18 En (MeV) Fig. 11. Comparison19 of experimental and calculated (n,) reaction cross sections of 92Mo. 4. International collaboration by networking and twinning Civil nuclear power is a major component of the energy production in Europe and in the world. The scarcity of R&D funds and markets compels to co-ordination of the nuclear research undertaken by the various actors, countries and organisations. A “durable” European structure in this respect is proposed to be a network of “centres of excellence”, of technical topics that, each one in his turn, will be organized in networks20. The strategic orientation should be given by a Steering Committee of the network, which will be assisted by a more operational structure (an operating agent, e.g. EC/JRC). Reliable theoretical models and their associated parameters are needed for computation of physical quantities that cannot be easily measured but are essential for the design of advanced nuclear energy production systems (e.g. fusion reactors and accelerator-driven systems) as well as for analysis of the performance of systems intended to reduce the inventory of long-lived radioisotopes in nuclear waste. Therefore it is important to harmonise the policies and standards of safety and environmental protection of EEC countries and EU member states and to integrate all activities in the domain of nuclear energy. The IFIN-HH successful project “Inter-Disciplinary Research and Applications based on Nuclear and Atomic Physics” (IDRANAP) under the EC/FP5/INCO2 “Support for Centres of Excellence” 21 is actually a useful experience in this respect. This proposal, largely guided by EC/JRC/IRMM-Geel and being finally the only one successful atomic- 20 MICHELANGELO Network: R&D needs of nuclear-energy industry and also long-term planning, EC, Brussels, October 2000. 21 EC/FP5/INCO2 (Confirming the international role of Community research, 1998-2002) “Support for Centres of Excellence”, Call identifier: ICFP599A1AM03, 1999-06-15 (deadline: 1999-10-15). 109 20 VLAD AVRIGEANU, MARILENA AVRIGEANU and TUDOR GLODARIU physics project from EEC under this FP5 call, has had the following scientific, social and economical main objectives: promotion in Romania of applications deriving from atomic and nuclear physics research; interdisciplinary research in fields such as ecology, health, biology, science of materials; to ensure conditions for scientific activities where students from Romanian or regional universities may find PhD programmes and an inspiring scientific climate to improve their training that counteract their tendency of migration in the West. However, negotiation of the actual contract did not take into account that the "excellence" does not characterize the work conditions of the unit submitting the proposal IDRANAP but the results of the staff obtained even in such conditions. Therefore, real helpful assistance should be provided firstly for improvement of the work conditions at the own site. Nevertheless, development of international collaboration by networking and twinning is decisive in order to enhance the expertise of our researchers as well as our research infrastructure so that we may be able to participate in European programmes. 110