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In bombardments of $^{244}\mathrm{Pu}$ with $^{34}\mathrm{S}$ we discovered the \ensuremath{\alpha}-decaying nuclide $^{273}110$. We conducted an extensive off-line search of the raw data for event sequences which fit the expected pattern of implantation in a position-sensitive detector and subsequent decay of $^{273}110$ and its descendants. We observed one three-member sequence of genetically linked \ensuremath{\alpha} decays, resulting in ${\mathit{E}}_{\mathrm{\ensuremath{\alpha}}}$=11.35 MeV, a half-life of 0.${3}_{\mathrm{\ensuremath{-}}0.2}^{+1.3}$ ms, and a production cross section of about 0.4 pb for $^{273}110$. Other possible $^{273}110$ event chains were also observed. The measured \ensuremath{\alpha}-particle energy for the N=163 nuclide $^{273}110$ provides direct evidence for a neutron shell closure at N=162. \textcopyright{} 1996 The American Physical Society.

In bombardments of ${}^{238}$U targets with 186-MeV ${}^{34}$S projectiles we discovered the $\ensuremath{\alpha}$-decaying nuclide ${}^{267}$108 with a half-life of ${19}_{\ensuremath{-}10}^{+29}$ ms, ${E}_{\ensuremath{\alpha}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}9.74$ to 9.87 MeV, and a production cross section of about 2.5 pb. The new nuclide was identified by measuring correlations in energy, time, and position to establish genetic links between its implantation in a position-sensitive silicon detector and subsequent $\ensuremath{\alpha}$ decay followed by $\ensuremath{\alpha}$ decays of known descendant nuclides.

In bombardments of ${}^{244}\mathrm{Pu}$ targets with 114- and 120-MeV ${}^{22}\mathrm{Ne}$ projectiles we detected 69 $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\alpha}$ correlations linking $\ensuremath{\alpha}$ decays of ${}^{261}\mathrm{Rf}$ and ${}^{257}\mathrm{No}.$ We observed one $\ensuremath{\alpha}$ peak with ${E}_{\ensuremath{\alpha}}=8.30\ifmmode\pm\else\textpm\fi{}0.06$ MeV for ${}^{261}\mathrm{Rf}$ and peaks with \ensuremath{\alpha}-particle energies 8.07\char21{}8.40 MeV for ${}^{257}\mathrm{No}.$ The half-life of ${}^{257}\mathrm{No}$ was measured to be $25\ifmmode\pm\else\textpm\fi{}3$ s. No correlations were found between $\ensuremath{\alpha}$ decays and subsequent spontaneous fission events, from which we calculated an upper limit of 1.5% for the fission branch of ${}^{257}\mathrm{No}$ and estimated an upper limit of 3% for the \ensuremath{\alpha}-decay branch of ${}^{262}\mathrm{Rf}.$ The cross section of the ${}^{244}\mathrm{Pu}{(}^{22}\mathrm{Ne}{,5n)}^{261}\mathrm{Rf}$ reaction was measured to be about 4 nb at both ${}^{22}\mathrm{Ne}$ energies used. We also report on some results from ${}^{242}\mathrm{Pu}{+}^{22}\mathrm{Ne}$ and ${}^{238}\mathrm{U}{+}^{26}\mathrm{Mg}$ bombardments.

A new statistical function has been found to simulate the angular distributions of evaporation residues produced by heavy-ions. Experimental results are compared with the calculated ones.

The reaction22Na(n, p)22Ne has been investigated at a neutron energy up to 1,000 eV by the time-of-flight method at the reaction IBR-30 of JINR. A neutron resonance was found in the reaction cross section. By fit, the parameters assigned to the resonance wereE0=145±11 eV;Γn0=1.6±0.2eV;Γp1=114±20eV. The presence of this resonance explains the large values for the thermal cross section of this reaction.

The36Cl(n,p)36S reaction cross-section was measured by the time-of-flight method in the IBR-30 pulsed reactor of the JINR. The measured cross-section shows three not previously observed neutron resonances with energies En = 1.3; 3.5 and 8.2 keV for which the parameters Ap=gΓnΓp/Γ: 0.07 ±0.01; 0.08 + 0.03 and 1.7 + 0.3 eV were determined, respectively. Comparison of these results with the excited states obtained by the36S(p, γ)37Cl reaction made possible a more exact determination of the scale energy of the37Cl nucleus excited states.

The 22Na(n,p) 22Ne reaction has been investigated at a neutron energy up to 1000 eV by the time-of-flight method at IBR-30 reactor of JINR. A neutron resonance was found in the reaction cross section. By fit, the parameters assigned to the resonance were Eo=145±11 eV; Γno; =1.6±0.2 eV; Γp1 =114±20 eV. The presence of this resonance explains large values for the thermal cross section of this reaction.