Upper limits for the existence of long-lived isotopes of roentgenium in natural gold

Journal Article · Sat Jan 15 00:00:00 EST 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.015801· OSTI ID:21499377

Dellinger, F; Kutschera, W; Forstner, O; Golser, R; Priller, A; Steier, P; Wallner, A; Winkler, G ^[1]

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1. University of Vienna, Faculty of Physics, Vienna Environmental Research Accelerator (VERA) Laboratory, Waehringer Strasse 17, A-1090 Wien (Austria)

A sensitive search for isotopes of a superheavy element (SHE) in natural gold materials has been performed with accelerator mass spectrometry at the Vienna Environmental Research Accelerator, which is based on a 3-MV tandem accelerator. Because the most likely SHE in gold is roentgenium (Rg, Z = 111), the search concentrated on Rg isotopes. Two different mass regions were explored: (i) For the neutron-deficient isotopes {sup 261}Rg and {sup 265}Rg, abundance limits in gold of 3x10{sup -16} were reached (no events observed). This is in stark contrast to the findings of Marinov et al.[Int. J. Mod. Phys. E 18, 621 (2009)], who reported positive identification of these isotopes with inductively coupled plasma sector field mass spectrometry in the (1-10)x10{sup -10} abundance range. (ii) Theoretical models of SHEs predict a region of increased stability around the proton and neutron shell closures of Z = 114 and N = 184. We therefore investigated eight heavy Rg isotopes, {sup A}Rg, A = 289, 290, 291, 292, 293, 294, 295, and 296. For six isotopes no events were observed, setting limits also in the 10{sup -16} abundance range. For {sup 291}Rg and {sup 294}Rg we observed two and nine events, respectively, which results in an abundance in the 10{sup -15} range. However, pileup of a particularly strong background in these cases makes a positive identification as Rg isotopes--even after pileup correction--unlikely.

• OSTI ID: 21499377
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 83, Issue 1; Other Information: DOI: 10.1103/PhysRevC.83.015801; (c) 2011 American Institute of Physics; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CORRECTIONS
GOLD
MASS
MASS SPECTROSCOPY
NEUTRON-DEFICIENT ISOTOPES
NEUTRONS
PLASMA
PROTONS
ROENTGENIUM ISOTOPES
SIMULATION
STABILITY
TANDEM ELECTROSTATIC ACCELERATORS
TRANSACTINIDE ELEMENTS
ACCELERATORS
BARYONS
ELECTROSTATIC ACCELERATORS
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
HADRONS
ISOTOPES
METALS
NUCLEONS
RADIOISOTOPES
SPECTROSCOPY
TRANSITION ELEMENTS
TRANSPLUTONIUM ELEMENTS
TRANSURANIUM ELEMENTS