Emission of sup 23 F and sup 24 Ne in cluster radioactivity of sup 231 Pa

Journal Article · Sun Nov 01 04:00:00 EST 1992 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.46.1939· OSTI ID:7157118

Price, P B ^[1]; Bonetti, R; Guglielmetti, A; Chiesa, C; Matheoud, R; Migliorino, C ^[2]; Moody, K J ^[3]

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1. Physics Department, University of California, Berkeley, California 94720 (United States) Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)
2. Istituto di Fisica Generale Applicata, Universita degli Studi di Milano, Milano (Italy) Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy)
3. Nuclear Chemistry Division, University of California, Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

Using a track-recording phosphate glass detector with a standard deviation {sigma}{sub {ital Z}}=0.23 charge unit, we collected {similar to}2100 tracks of energetic clusters emitted from {sup 231}Pa. Of these, 1348 survived cuts on energy, angle of incidence to the detectors, and {chi}{sup 2}. All but one of them are consistent with {sup 24}Ne, and our measured branching ratio, {ital B}(Ne/{alpha})=(13.4{plus minus}1.7){times}10{sup {minus}12}, for an alpha-decay half-life for {sup 231}Pa of 3.28{times}10{sup 4} yr. This value of {ital B} is a factor of 2.2 greater than was determined by Tretyakova {ital et} {ital al}., who observed 252 Ne decays. We identify one event as {sup 23}F, the nucleus predicted by cluster emission models to have the second highest branching ratio for emission from {sup 231}Pa. This corresponds to a branching ratio {ital B}(Ne/F)=1347{sub {minus}940}{sup +6440}, the 1{sigma} limits being governed by inverse Poisson statistics. Published models predict lower values of {ital B}(Ne/F), ranging from 3 to 400. Our event, if its 4{sigma} deviation from Ne is regarded as sufficient evidence for F, would be the first example of emission of an odd-{ital Z} cluster in spontaneous cluster radioactivity.

• DOE Contract Number: AC03-76SF00098; W-7405-ENG-48
• OSTI ID: 7157118
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Journal Name: Physical Review, C (Nuclear Physics); (United States) Vol. 46:5; ISSN 0556-2813; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

663210* -- Ground-State Radioactivity-- (1992-)
663590 -- Nuclear Mass Ranges-- A=220 & Above-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY
ALPHA DECAY RADIOISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BRANCHING RATIO
DATA
DECAY
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
FLUORINE 23
FLUORINE ISOTOPES
HEAVY ION DECAY RADIOISOTOPES
HEAVY NUCLEI
INFORMATION
ISOTOPES
LIGHT NUCLEI
MINUTES LIVING RADIOISOTOPES
NEON 24
NEON 24 DECAY RADIOISOTOPES
NEON ISOTOPES
NUCLEAR DECAY
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
PROTACTINIUM 231
PROTACTINIUM ISOTOPES
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
YEARS LIVING RADIOISOTOPES