Details

Autor(en) / Beteiligte

• Belli, P.
• Bernabei, R.
• Boiko, R. S.
• Cappella, F.
• Caracciolo, V.
• Cerulli, R.
• Danevich, F. A.
• Incicchitti, A.
• Kasperovych, D. V.
• Kobychev, V. V.
• Laubenstein, M.
• Leoncini, A.
• Merlo, V.
• Poda, D. V.
• Polischuk, O. G.
• Sokur, N. V.
• Tretyak, V. I.

Titel

Search for alpha and double alpha decays of natural Nd isotopes accompanied by gamma quanta

Ist Teil von

• The European physical journal. A, Hadrons and nuclei, 2024-03, Vol.60 (3), Article 46

Ort / Verlag

Berlin/Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2024

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• From 7 naturally occurring Nd isotopes, 5 are unstable in relation to α decay. If an excited level of the daughter nucleus is populated, or the daughter nucleus is unstable, γ quanta can be emitted. We used an ultra-low background spectrometry system with 4 high purity germanium (HPGe) detectors (about 225 cm 3 volume each) to search for such decays using a highly purified Nd-containing sample with mass of 2.381 kg. Measurements were performed at the INFN Gran Sasso underground laboratory (with an overburden of about 3600 m w.e.) during 51,237 h. Half-life limits for α decays of 143 Nd and 145 Nd were determined to be T 1/2 ( 143 Nd) > 1.1 × 10 20  year and T 1/2 ( 145 Nd) > 2.7 × 10 19  year at 90% C.L. This is an increase of three and two orders of magnitude, respectively, compared with the most restrictive values currently given in literature. A limit for α decay of 144 Nd to the excited level of 140 Ce with E exc  = 1596.2 keV was determined for the first time as T 1/2 ( 144 Nd →  140 Ce * ) > 9.3 × 10 20  year. Restriction for the α decay of 146 Nd to the excited level of 142 Ce with E exc  = 641.3 keV was increased by 3 orders of magnitude to T 1/2 ( 146 Nd →  142 Ce * ) > 1.4 × 10 21  year. For α and 2 α decays of 148 Nd, first T 1/2 limits were set as 4.2 × 10 18  year and 2.1 × 10 20  year, respectively.