Pion-transfer reaction spectroscopy of inverse kinematics for studies of deeply bound pionic atoms in heavy nuclei

doi:10.1016/0168-9002(90)90180-E

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Volume 292, Issue 3, 15 July 1990, Pages 619-628

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Abstract

A new type of nuclear reaction spectroscopy using inverse kinematics is proposed and discussed with a special emphasis on the application to charge-exchange pion-transfer reactions such as (d, ²He) and (t, ³He) to embed real pions onto heavy nuclei forming deeply bound pionic atoms, which were predicted by Toki and Yamazaki to have narrow widths due to the repulsive strong-interaction potential. A typical case considered is to use heavy-ion projectiles of 400 MeV/u range on a light target such as d or t and to measure the recoil particles of low-energy range corresponding to forward scattering. The recoil momentum is shown to be nearly equal to the Lorentz-invariant momentum transfer of the reaction, typically, around 140 MeV/c, which is proportional to the excitation energy. Compared to the conventional method, the present inverse-kinematics one not only provides a better energy resolution (around 100 keV at 140 MeV excitation) but also permits studies of π⁻ bound states on unstable nuclei, hitherto unconceivable objects for spectroscopy. Some experimental configurations to be used in a cooled circulating beam are discussed.

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Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Pion-transfer reaction spectroscopy of inverse kinematics for studies of deeply bound pionic atoms in heavy nuclei

Abstract

Phys. Lett.

Phys. Lett.

SATURNE Proposal no. 214

Nucl. Phys.

Deeply bound pionic states in heavy nuclei

Mesic atoms and mesic nuclei

Formation of deeply bound pionic atoms in the (d,<sup>3</sup>He) reaction

Deeply bound pionic atoms on β -unstable nuclei

Fission as a filter for the study of heavy hypernuclei and other exotic atoms and nuclei

Deeply bound pionic atoms with resonant Compton scattering