Abstract
For the violent collisions of 27 MeV/nucleon40Ar with Ag, coincidence measurements have been made between heavy residues and intermediate mass fragments (3≦Z≦14) or light charged particles. From the analysis of the correlation between heavy residues (mass and velocity) and intermediate mass fragments, the main characteristics of the dominant mechanisms, fusion and partially damped collisions preceded or accompanied by a preequilibrium emission, are presented. Balances concerning mean values of parallel linear momentum, mass and atomic number, are established and confirm that a complete description of violent collisions was obtained. Then thermalization is discussed, first in terms of excitation energies derived from kinematics between heavy residues and intermediate mass fragments, and secondly in terms of initial temperature estimates derived from light charged particle spectra. Very hot nuclei (T⋍5.7–6.6 MeV) are produced over a large impact parameter range from very central collisions to medium peripheral ones. Various experimental results are compared to predictions obtained with semi-classical calculations (Landau-Vlasov equation). From their good agreement one may conclude that, depending on the impact parameter, thermal equilibrium is achieved within 4–10×10−22 s.
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Gregoire, C., Tamain, B.: Ann. Phys. Fr.11, 323 (1986)
Dayras, R.: J. Phys.47C, 13 (1986)
Gelbke, C.K., Boal, D.H.: Prog. Part. Nucl. Phys.19, 33 (1987)
Guerreau, D.: In: Nuclear matter and heavy ion collisions, p. 187, Soyeur, M., Flocard, H., Tamain, B., Porneuf, M. (eds.) New York: Plenum Publishing Corporation 1989
Borderie, B., Rivet, M.F., Tassan-Got, L.: Ann. Phys. Fr.15, 287 (1990)
Toepffer, C., Cheuk-Yin Wong: Phys. Rev. C25, 1019 (1982)
Köhler, H.S., Nilsson, B.S.: Nucl. Phys. A417, 541 (1984)
Aichelin, J., Bertsch, G.: Phys. Rev. C31, 1730 (1985)
Kruse, H., Jacak, B.V., Molitoris, J.J., Westfall, G.D., Stocker, H.: Phys. Rev. C31, 1770 (1985)
Gregoire, C., Remaud, B., Sebille, F., Vinet, L., Raffray, Y.: Nucl. Phys. A465, 317 (1987)
Cassing, W.: Z. Phys. A — Atomic Nuclei327, 87 (1987)
Cassing, W.: Z. Phys. A — Atomic Nuclei327, 447 (1987)
Cassing, W.: Z. Phys. A — Atomic Nuclei329, 471 (1988)
Remaud, B., Gregoire, C., Sebille, F., Schuck, P.: Nucl. Phys. A488, 423c (1988)
Borderie, B., Montoya, M., Rivet, M.F., Jouan, D., Cabot, C., Fuchs, H., Gardes, D., Gauvin, H., Jacquet, D., Monnet, F.: Phys. Lett. B205, 26 (1988)
Rivet, M.F., Borderie, B., Gregoire, C., Jouan, D., Remaud, B.: Phys. Lett. B215, 55 (1988)
Gardes, D., Monnet, F., Barbey, S., Borderie, B., Dumail, M., Gobbi, A., Rivet, M.F., Volkov, P.: Nucl. Instrum. Methods A247, 347 (1986)
Borderie, B., Rivet, M.F., Cabot, C., Fabris, D., Gardes, D., Gauvin, H., Hanappe, F., Peter, J.: Z. Phys. A — Atoms and Nuclei318, 315 (1984)
Rivet, M.F., Borderie, B., Gauvin, H., Gardes, D., Cabot, C., Hanappe, F., Peter, J.: Phys. Rev. C34, 1282 (1986)
Kaufman, S.B., Steinberg, E.P., Wilkins, B.D., Unik, J., Gorski, A.J., Fluss, M.J.: Nucl. Instrum. Methods115, 47 (1974)
Lefort, M.: In: Heavy ion collisions, Vol. 2, p. 47, Bock, R. (ed.), Amsterdam: North Holland 1980
Schröder, W.U., Huizenga, J.R.: In: Treatise on heavy ion science. Vol. 2, p. 115, Bromley, D.A. (ed.), New York: Plenum Press 1984
Galin, J., Moretto, L.G., Babinet, R., Schmitt, R., Jared, R., Thompson, S.G.: Nucl Phys. A255, 472 (1975)
Vaz, L.C., Logan, D., Alexander, J.M., Duek, E., Guerreau, D., Kowalski, L., Rivet, M.F., Zisman, M.S.: Z. Phys. A — Atoms and Nuclei311, 89 (1983)
Gadi-Dayras, F.Z.: Ph. D. Thesis, Orsay (1988) (unpublished)
Zamick, L.: Phys. Lett. B45, 313 (1973)
Gregoire, C., Jacquet, D., Pi, M., Remaud, B., Sebille, F., Suraud, E., Schuck, P., Vinet, L.: Nucl. Phys. A471, 399c (1987)
Gogny, D.: Proc. Int. conf. on nuclear self-consistant field, p. 176, Ripka, G., Porneuf, P. (eds.), Amsterdam: North Holland 1975
Sebille, F., Royer, G., Gregoire, C., Remaud, B., Schuck, P.: Nucl. Phys. A501, 137 (1989)
Randrup, J.: Nucl. Phys. A383, 468 (1982)
Tassan-Got, L., Stephan, C.: Nucl. Phys. A524, 121 (1991)
Randrup, J., Vandenboch, R.: Nucl. Phys. A474, 219 (1987)
Ericson, T., Strutinsky, V.: Nucl. Phys.8, 284 (1958)
Alexander, J.M., Guerreau, D., Vaz, L.C.: Z. Phys. A — Atomic and Nuclei305, 313 (1982)
Zielinska-Pfabe, M., Gregoire, C.: Phys. Rev. C37, 2594 (1988)
Guerreau, D., Galin, J.: Private communication of unpublished results
Hubert, F., Moral, R. Del, Dufour, J.P., Emmermann, H., Fleury, A., Poinot, C., Pravikoff, M.S., Delagrange, H., Lleres, A.: Nucl. Phys. A456, 535 (1986)
Moretto, L.: Nucl. Phys. A247, 211 (1975)
Moretto, L., Wozniack, G.J.: Prog. Part., Nucl. Phys.21 (1988)
Borderie, B., Rivet, M.F., Cabot, C., Fuchs, H., Gardes, D., Hanappe, F., Jouan, D., Montoya, M.: Z. Phys. A — Hadrons and Nuclear338, 369 (1991)
Toke, J., Schröder, W.U., Huizenga, J.R.: Phys. Rev. C40, 1577 (1989)
Wile, J.L., Datta, S.S., Schröder, W.U., Huizenga, J.R., Toke, J., Souza, R.T. De: Phys. Rev. C39, 1845 (1989)
Gonin, M., Cooke, L., Hagel, K., Lou, Y., Natowitz, J.B., Schmitt, R.P., Srivastava, B., Turmel, W., Utsunomiya, H., Wada, R., Fornal, B., Nardelli, G., Nebbia, G., Viesti, G., Zanon, R., Prete, G., Gonthier, P., Wilkins, B.: Phys. Lett. B217, 406 (1989)
Nebbia, G., Hagel, K., Fabris, D., Majka, Z., Natowitz, J.B., Schmitt, R.P., Sterling, B., Mouchaty, G., Berkowitz, G., Strozewski, K., Viesti, G., Gonthier, P.L., Wilkins, B., Namboodiri, M.N., Ho, H.: Phys. Lett. B176, 20 (1986)
Fuchs, H., Burgel, M., Homeyer, H., Ingold, G., Jahnke, U., Thoma, G.: Phys. Rev. C31, 465 (1985)
Terlau, W., Burgel, M., Budzanowski, A., Fuchs, H., Homeyer, H., Roschert, G., Uckert, J., Vogel, R.: Z. Phys. A — Atomic Nuclei330, 303 (1988)
Bougault, R., Delaunay, F., Genoux-Lubain, A., Le Brun, C., Lecolley, J.F., Lefebvres, F., Louvel, M., Steckmeyer, J.C., Adloff, J.C., Bilwes, B., Bilwes, R., Glaser, M., Rudolf, G., Scheibling, F., Stuttge, L., Ferrero, J.L.: Nucl. Phys. A488, 255c (1988)
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Experiment performed at the GANIL National Facility in Caen, France
It is a pleasure for us to thank J.C. Steckmeyer and L. Tassan-Got for fruitful discussions and for providing us with some calculations. We also thank the whole GANIL staff and S. Barbey and P. Lelong for their strong technical support before and during the experiment. H.F. wants to express his gratitude to the IPN Orsay for the kind hospitality during his sabbatical.
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Jouan, D., Borderie, B., Rivet, M.F. et al. Dynamics and thermalization in violent collisions between40Ar and Ag at 27 MeV/nucleon. Z. Physik A - Hadrons and Nuclei 340, 63–77 (1991). https://doi.org/10.1007/BF01284482
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DOI: https://doi.org/10.1007/BF01284482