From in-plane to out-of-plane enhancement of the directed flow in 64Zn on 58Ni collisions between 35 and 79 MeV/u

doi:10.1016/0370-2693(94)91053-7

Physics Letters B

Volume 331, Issues 3–4, 7 July 1994, Pages 285-289

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Abstract

The azimuthal distributions of light particles relative to the reaction plane have been measured for several bins of experimentally estimated impact parameters in the reactions of ⁶⁴Zn + ⁵⁸Ni at energies between 35 and 79 MeV/u. An in-plane enhancement for mid-rapidity Z = 1, 2, 3 particles is observed at low incident energy but gradually evolves to out-of-plane enhancement (squeeze-out effect) with increasing energy. This evolution depends on the impact parameter in a way similar to the flow parameter. The energies for this system at which the azimuthal distribution is uniform are lower than the corresponding balance energies.

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^☆: Experimental performed at GANIL.

²: On leave of absence from IPNE, Heavy Ion Department, Bucuresti, Roumania.

³: On leave of absence from Institut de Physique Nucléaire, Orsay, France.

⁴: On leave of absence from Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil.

⁵: Present address: Brookhaven National Laboratory, New York, USA.

¹: On leave of absence from Institute of Modern Physics, Lanzhou, P.R. China.

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From in-plane to out-of-plane enhancement of the directed flow in 64Zn on 58Ni collisions between 35 and 79 MeV/u☆

Abstract

Phys. Lett. B

Phys. Lett. B

Phys. Lett. B

Phys. Lett. B

Phys. Lett.

Nucl. Phys. A

Nucl. Phys. A

Phys. Rev. C

Phys. Rev. C

From in-plane to out-of-plane enhancement of the directed flow in $^{64} Zn$ on $^{58} Ni$ collisions between 35 and 79 MeV/u☆