Mass Numbers of Neutron-Deficient Dysprosium Isotopes; NOMBRES DE MASSE DES ISOTOPES DU DYSPROSIUM DEFICIENTS EN NEUTRONS

Technical Report · Sat Oct 31 04:00:00 EST 1959

OSTI ID:4279987

Dobronova, A N; Krijansky, L M; Mourine, A M; Pokrovsky, V N

Studies of the genetic bonds of Dy isotopes with Tb and Gd daughter elements indicated the possible existence of isotopes with A = 159, 157, 155, and 153. To verify this, an attempt was made to determine directly the Dy isotopic masses formed in Ta deep: spallation. The Dy fraction was separated by mass spectrometer, and the gamma spectra of separated Dy isotopes were determined with a scintillation spectrometer. The results confirmed the existence of Dy with A = 159, 157 155 153, and possibly, 151. The weak activity of. Dy/sup 159/ and still weaker Dy/sup 151/ prevented further studies. The following data were found for Dy/sup 157/ T/sub 1/2/, = 8.5 + 0.5 hr; no daughter activity observed; gamma spectrum lines 80 and 325 kev. For Dy/sub 155/ T/sub 1/2/, = 9 plus or minus 2 hr; daughter activity with T/sub 1/2/ approximates 5 days (Tb/sup 155/ ); gamma spectrum lines 80 and 227 kev. For Dy/sub 153/ : T/sub 1/2/, = 7 plus or minus 3 hours; daughter activity with T/sub 1/2/ approximates 2 davs (Tb/sup 153); gamma spectrum line 80 kev. (R.V.J.)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-13-005007
• OSTI ID: 4279987
• Report Number(s): CEA-tr-R556
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BINDING ENERGY
DYSPROSIUM 151
DYSPROSIUM 153
DYSPROSIUM 155
DYSPROSIUM 157
DYSPROSIUM 159
DYSPROSIUM ISOTOPES
ELEMENTS
ENERGY LEVELS
GADOLINIUM
GAMMA RADIATION
HALF-LIFE
MASS
MASS SPECTROMETERS
MEASURED VALUES
NEUTRONS
PHYSICS AND MATHEMATICS
RADIOACTIVITY
SCINTILLATION COUNTERS
SEPARATION PROCESSES
SPECTRA
SPECTROMETERS
TANTALUM
TERBIUM
TERBIUM 153
TERBIUM 155