Isotope Shift Measurements of Samarium Muonic Atom X-rays in Thin Solid Deuterium Films

在这项研究中，我们提出了在薄的固体氢膜中注入稳定的钐同位素，通过直接的μ子转移反应形成μ子原子，然后用这些注入的离子进行μ子X射线光谱，以确定同位素位移和转移率。μ子原子X射线的同位素位移测量了原子核的核电荷分布，钐同位素特别令人感兴趣，因为它们的核特性显示出非常突然的变化。这一发展对于扩展固体氢膜方法以在未来产生具有不稳定核的μ子原子至关重要。在RIKEN-RAL的μ子设施中，将大约1 ppm的稳定钐同位素1 <148>Sm和1 <152>Sm注入到薄的固体氘膜中，获得了非常有希望的结果。在4.5MeV的钐中观察到了清晰的2 p → 1 s μ子跃迁的X射线峰，同位素位移与^<148>Sm仍具有球形核，而^ Sm的核<152>已高度变形相一致。

In this research, we proposed to implant stable samarium isotopes in thin solid hydrogen films to form muonic atoms through the direct muon transfer reaction, and then conduct muonic X-ray spectroscopy with those implanted ions to determine isotope shifts and transfer rates. The isotope shift of muonic atom X-rays measures the nuclear charge distribution of the nucleus, and samarium isotopes are of particular interest because they show very abrupt changes in their nuclear characteristics. This development is crucial in order to expand the solid hydrogen film method to produce muonic atoms with unstable nuclei in the future. Very promising results were obtained at the RIKEN-RAL muon facility with stable samarium isotopes ^<148>Sm and ^<152>Sm of about 1 ppm implanted into a thin solid deuterium film. Clear X-rays peaks from the 2p→1s muonic transitions in samarium (about 4.5MeV) were observed, and the isotope shift was consistent with that ^<148>Sm still has a spherical nucleus, while the nucleus of ^<152>Sm is highly deformed.