Emission of helium ions after antiproton annihilation in nuclei

doi:10.1016/0375-9474(88)90547-7

Nuclear Physics A

Volume 485, Issues 3–4, August 1988, Pages 445-460

https://doi.org/10.1016/0375-9474(88)90547-7 Get rights and content

Abstract

Spectra of hydrogen and helium ions emitted after stopped antiproton annihilation in nuclei have been measured with a Si-detector telescope. Targets of ¹²C, ⁴⁰Ca, ⁶³Cu, ⁹²Mo, ⁹⁸Mo and ²³⁸U were used. The ³He and ⁴He energy spectra can be fitted with the exponential function e^−E/T. The parameter T is essentially independent of the target mass number A. A simple pickup model reproduces the ⁴He/³He ratios as a function of Z and N (target proton and neutron number). The proton spectra from the ²³⁸U target indicate that some protons are also emitted by the fission fragments.

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¹: Permanent address: Florida State University, Tallahassee, Florida 32306, USA.

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Emission of helium ions after antiproton annihilation in nuclei

Abstract

Nucl. Phys.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Phys. Lett.

At. Data Nucl. Data Tables

Nucl. Instr. Meth.