A neutron multiplicity detector for rare spontaneous fission events

The 3He long-counter TETRA at the ALTO ISOL facility

“…The 4π neutron array TETRA was constructed at JINR [14]. It consists of 80 counters ˇlled by 3 He at 7 atm with 1% admixture of CO 2 , the active volume has 50 cm in length and ∅33 mm.…”

Search for Spontaneous fission activity in Salton Sea and Atlantis II hot brines

“…Both specimens were also measured simultaneously and will be named below as Atlantis II samples. We shall give a brief description of the detector, for more details we refer to [5]. The detector consisted of a plexiglass unit 550 mm in diameter and 700 mm high, with a 150mm dia through channel in the middle to place the sample under study.…”

“…The sensitivity of measurements using the neutron detector reached 10-t2-2 x 10 -13 g/g in the 9-range of 2-4. Therefore it was interesting to remeasure the activity of both the Atlantis II and Salton Sea samples using the neutron detector of the JINR Laboratory of Nuclear Reactions, the sensitivity of which reached 10-13 g/g (5). Such measurements are of interest in view of the fact that it was impossible to eliminate the possibility of considerable losses of the sought nuclide in the process of the chemical processing performed in (3).…”

Search for Superheavy Elements in the Nature

“…Special scintillation counting tubes [39,75] In [42,55,76] it is reported on neutron multiplicity measurements by means of 3 He-counting tubes.…”