Nonstatistical structures in the excitation functions of20Ne(16O,12C)24Mg and20Ne(16O,20Ne)16O reactions

The data on the excitation functions of²⁰Ne(¹⁶O,¹²C)²⁴Mg,²⁰Ne(¹⁶O,¹²C)²⁴Mg^*(1.37, 2⁺),²⁰Ne(¹⁶O,¹²C)²⁴Mg^*(4.12, 4⁺+4.24, 2⁺) +²⁰Ne(¹⁶O,¹²C^*(4.44, 2⁺))²⁴Mg,²⁰Ne(¹⁶O,¹²C)²⁴Mg^*(6.01, 4⁺+6.43, 0⁺),²⁰Ne(¹⁶O,²⁰Ne)¹⁶O,²⁰Ne(¹⁶O,²⁰Ne^*(1.63, 2⁺))¹⁶O, and²⁰Ne(¹⁶O,²⁰Ne^*(4.25, 4⁺))¹⁶O reactions atθ _lab=13° fromE _c.m.=22.8 to 38.6 MeV have been subjected to a statistical analysis comprising of the calculations of the distribution of cross sections, deviation functions, cross-correlation functions, summed excitation functions, cross-channel correlation coefficients and coherence widths. The analysis confirms the existence of nonstatistical structures atE _c.m.=24.6, 27.8, 31.7 and 35.5 MeV, and identifies a new structure of the same nature atE _c.m. =25.6 MeV.     

Infrared spectroscopy of 17O- and 18O-enriched carbon dioxide in the 1700–8300 cm−1 wavenumber region

The assignment of the high resolution Fourier transform spectra of carbon dioxide enriched in ¹⁷O and ¹⁸O which were recorded in LADIR (Paris, France) with the Bruker IFS 125-HR between 1800 and 9000 cm^?1 and in USTC (Hefei, China) with the Bruker IFS 120-HR between 1700 and 9000 cm^?1 was performed. In total 239 bands of 12 isotopologues: ¹⁶O¹²C¹⁶O, ¹⁶O¹²C¹⁸O, ¹⁶O¹³C¹⁶O, ¹⁶O¹³C¹⁸O, ¹⁸O¹²C¹⁸O, ¹⁸O¹³C¹⁸O, ¹⁶O¹²C¹⁷O, ¹⁷O¹²C¹⁷O, ¹⁷O¹²C¹⁸O, ¹⁶O¹³C¹⁷O, ¹⁷O¹³C¹⁷O and ¹⁷O¹³C¹⁸O were observed. Among them, 99 bands were observed for the first time. The majority of new observed bands belong to ¹⁷OCO isotopologues. The positions of 23,003 lines were determined with the experimental uncertainty on the level of 0.001 cm^?1. The spectroscopic constants were fitted to the observed line positions for all observed bands.     

Measuring elastically scattered 18 MeV deuterons and the shape of nuclei

The angular distributions of 18 MeV deuterons elastically scattered on ⁹Be, ¹⁰B, ¹³C, ²⁴Mg, and ²⁵Mg nuclei are measured using the U-150M cyclotron at the Institute for Nuclear Physics (Almaty, Kazakhstan). The free parameters of the scattering matrix of parametrized phase analysis are determined. We estimate the sign of the nucleus??s deformation for even nuclei ⁶⁴Ni, ⁶⁴Zn, ¹⁴⁴Sm, ¹⁸²W, ¹⁸⁴W, ¹⁹²Os, ²³⁸U, and odd nuclei ⁵⁹Co, ⁶³Cu, ⁸⁹Y, ⁹³Nb, ¹⁰³Rh, ¹⁰⁷Ag, ¹⁸¹Ta, ¹⁹⁷Au, ²⁰⁵Tl, and ²⁰⁹Bi.     

Role of thermal and photobeta decays in processes of nucleosynthesis of problematic p nuclei of 113In, 115Sn, 92,94Mo, and 96,98Ru in massive stars

The temperature dependence of the rates of ¹¹³Cd →¹¹³In, ¹¹⁵In →¹¹⁵Sn, ⁹²Zr→⁹²Nb →⁹²Mo, ⁹⁴Zr→⁹⁴Nb →⁹⁴Mo, ⁹⁶Mo →⁹⁶Tc→⁹⁶Ru, and ⁹⁸Mo→⁹⁸Tc→⁹⁸Ru thermal beta transitions was studied at temperatures of massive-star matter in the range of 1 × 10⁸–6 × 10⁹ K. These decays are the possible channel of synthesis of the p nuclei of ¹¹³In, ¹¹⁵Sn, ⁹²,⁹⁴Mo, and ⁹⁶,⁹⁸Ru. The abundances of these nuclei present a challenge for models that study the explosivemechanism of synthesis. The contribution of photobeta decay to the synthesis of the aforementioned p nuclei was estimated. It was shown that the channel of thermal beta decay for ¹¹³In, ¹¹⁵Sn, ⁹⁴Mo, and ⁹⁸Ru p nuclei and the channel of photobeta decay for the ⁹⁶Mo p nucleus could be efficient at the high-temperature quasiequilibrium stage of massive-star evolution.     

Transition probabilities of the X1Σ+, A1Π, B1Δ, C1Σ+, and D1Π states of the AlO+ cation

ABSTRACT

This study computes the potential energy curves of the X¹Σ⁺, A¹Π, B¹Δ, C¹Σ⁺, and D¹Π states of AlO⁺ cation and the transition dipole moments between them. The orders of the rotationless radiative lifetimes are 10–100?μs for the A¹Π state, 1–1000?ms for the B¹Δ state, 10?ns for the first well and 100?ns for the second well of the C¹Σ⁺ state, and 1?μs for the D¹Π state. Emissions of the B¹Δ–A¹Π and D¹Π–C¹Σ⁺ systems are so weak that they are hardly measured via spectroscopy, the emissions of the C¹Σ⁺–X¹Σ⁺, C¹Σ⁺–A¹Π, and D¹Π–X¹Σ⁺ systems are so strong that they can be detected readily, and emissions of the A¹Π–X¹Σ⁺ and D¹Π–A¹Π systems can be observed through spectroscopy only by a significant effort. There is a strong great similarity between spontaneous emissions of the A¹Π–X¹Σ⁺ system of the AlO⁺ cation and the A²Π–X²Σ⁺ system of the AlO radical. The emissions of the A²Π–X²Σ⁺ system of the AlO radical have been measured in outer space Therefore, it is highly possible that the emissions of the A¹Π–X¹Σ⁺ system of the AlO⁺ cation can be detected in the astrophysical media.     

Precision atomic mass spectrometry with applications to fundamental constants, neutrino physics, and physical chemistry

We present a summary of precision atomic mass measurements of stable isotopes carried out at Florida State University. These include the alkalis ⁶Li, ²³Na, ^39,41K, ^85,87Rb, ¹³³Cs; the rare gas isotopes ^84,86Kr and ^{129,130,132,136}Xe; ^17,18O, ¹⁹F, ²⁸Si, ³¹P, ³²S; and various isotope pairs of importance to neutrino physics, namely ^74,76Se/^74,76Ge, ¹³⁰Xe/¹³⁰Te, and ¹¹⁵In/¹¹⁵Sn. We also summarize our Penning trap measurements of the dipole moments of PH^?+? and HCO^?+?.     

The evaluation of half-lives and other decay data used in nuclear astrophysics and cosmochronology

The current status of some decay data used in nuclear astrophysics and cosmochronology is presented. The half-life of ⁷⁹Se has been evaluated as 3.6(3) × 10⁵ yr. The total energy of non-neutrino radiation released in act of ³⁷Ar decay has been obtained being 2.709 (16) keV per disintegration. The recommended half-life values of the long-lived radionuclides (T _1/2 ≳ 10⁶ yr) of ²⁶Al, ⁴⁰K, ⁵³Mn, ⁶⁰Fe, ⁸⁷Rb, ⁹³Zr, ⁹⁸Tc, ¹⁰⁷Pd, ¹²⁹I, ¹³⁵Cs, ¹⁴⁶Sm, ¹⁷⁶Lu, ¹⁸²Hf, ¹⁸⁷Re, ²⁰⁵Pb, ²³²Th, ²³⁵U, ²³⁸U, ²⁴⁴Pu, and ²⁴⁷Cm are given based on the evaluations published until 2010.     

Statistical analysis of24Mg+24Mg elastic and inelastic scattering

The data on the excitation functions of²⁴Mg+²⁴Mg elastic and inelastic (²⁴Mg +²⁴Mg^*(2⁺),²⁴Mg^*(2⁺)+²⁴Mg^*(2⁺),²⁴Mg+²⁴Mg^*(4⁺),²⁴Mg^*(4⁺)+²⁴Mg^*(2⁺),²⁴Mg+²⁴Mg^*(6⁺)) scattering fromE _c.m=42 to 56 MeV have been subjected to a statistical analysis consisting of calculations of deviation function, cross-correlation function, cross-channel correlation coefficients, coherence widths, and the distribution of cross sections. On the basis of the analysis resonant structures atE _c.m=45.70, 46.65, 47.35 and 47.75 MeV have been confirmed. Two new resonant structures atE _c.m=44.55 and 50.50 MeV have been identified.     

Investigation of neutron deficient nuclei in the region 28<N,Z <50 with the help of heavy ion compound reactions

In-beamγ ray spectroscopy withγ singles spectra,γγ coincidences andγ ray angular distributions has been performed with several target-projectile combinations:^natCa +³²S,^natCa +⁴⁰Ca,⁵⁴Fe +¹⁴N,⁵⁸Ni +¹²C,⁵⁸Ni +¹⁴N,⁶⁶Zn +¹⁶O,⁶⁸Zn +¹⁶O. Level schemes of⁶⁶Ge,⁶⁸Ge,⁶⁹As,⁷⁰Se,⁷⁴Kr,⁸⁰Sr and⁸²Sr have been deduced. The following level energies and spin-parity assignments have been found:⁶⁶Ge: 957.4 keV, 2⁺; 1693.7; 2174.7, (4⁺); 3685.7; 4207.5;⁶⁸Ge: 1015.8, 2⁺; 1777.9, 2⁺; 2267.9, 4⁺; 2428.8, 3(⁺); 2649.1, 3^?; 3582.3, (5^?); 3649.3, (5^?); 3696.2, (6⁺); 3883.3, (6^?); 4054.4, (7^?); 4454.6; 4837.3;⁶⁹As: 98.2; 164.6;789.6;863.2; 1306;2160;2210.4;2831.5;3258.3;3263.5;3991.1;5195.7;⁷⁰Se: 945.4, 2⁺; 1600.9; 2039.4, (4⁺);⁷⁴Kr: 455.7, 2⁺; 1013.5, (4⁺); 1781.5;⁸⁰Sr: 385.4, 2⁺; 980.2, (4⁺); 1763.2, (6⁺);⁸²Sr: 573.4, 2⁺; 1328.5,(4⁺); 2229.6,(6⁺). γ ray activity spectra have been measured after the bombardment of natural Ca with³²S. The half-life of the new isotope⁶⁹Se has been found to be 27±3 sec. Recoil distance Doppler-shift measurements have been performed with the reactions^62,64Ni,⁶⁶zn(¹⁶O, 2n)^{76, 78} Kr,⁸⁰Sr. The following half-lives have been determined:⁷⁶Kr: 423.8 keV, 2⁺, 37±5 psec; 1034.2,4⁺, 5.7±1.6;⁷⁸Kr: 455.3, 2⁺, 25±3; 1120.0, 4⁺, 3.8±1;⁸⁰Sr: 385.4, 2⁺, 44±6. The energy and half-life systematics of the first excited state of even-even nuclei suggest a maximum of nuclear deformation in the region 28≦N, Z≦50 near ₃₈ ⁷⁶ Sr₃₈ or ₄₀ ⁷⁸ Zr₃₈.     

Molecular constants for NSCl and NSF

The complete infrared spectrum of gaseous NSCl, including the hitherto unobserved ν₃, is reported. A set of force constants for gaseous NSCl consistent with a number of pieces of independent data such as the isotopic shifts (¹⁴N³²S³⁵Cl, ¹⁵N³²S³⁵Cl, ¹⁴N³²S³⁷Cl, ¹⁵N³²S³⁷Cl, ¹⁴N³⁴S³⁵Cl and ¹⁵N³⁴S³⁵Cl), centrifugal distortion constants (¹⁴N³²S³⁵Cl), and the inertia defect (¹⁴N³²S³⁵Cl) has been computed. Also, the force field of NSF has been redetermined using the vibrational frequencies and the centrifugal distortion constants.     

Low-lying electronic states of BeH+ with the effect of inner electrons

The potential energy curves of the low-lying electronic states of BeH⁺ molecular ion are performed by using highly accurate multi-reference configuration interaction with AV5Z basis sets for H atom and ACV5Z basis set for Be atom, 1s inner shell of Be is considered as the core orbit and the active orbit, respectively, which are used to characterise the spectroscopic properties of a manifold of singlet and triplet states. Fourteen electronic states correlated with eight dissociation channels are investigated, we have found that the a³Σ⁺ and c³Σ⁺ both are bound states, the 3³Σ⁺ possesses double wells, and the C¹Σ⁺, 3³Σ⁺, 2³Π, 2¹Π, 1¹Δ, 1³Δ, 2³Δ and 2¹Δ states are studied for the first time. Transition dipole moment, Franck–Condon factors q_υ′υ^″ and Einstein coefficients A_υ′υ^″ for A¹Σ⁺–X¹Σ⁺, 2¹Π–B¹Π, c³Σ⁺–a³Σ⁺ and b³Π–a³Σ⁺ systems have been calculated. Radiative lifetime of A¹Σ⁺–X¹Σ⁺ band system has also been determined.     

Superheavy research in Japan

At RIKEN (The Institute of Physical and Chemical Research) in Japan, we have performed experiments to study the productions and decays of the heaviest elements produced by one-neutron emission channels of ²⁰⁸Pb and ²⁰⁹Bi based heavy-ion-induced fusion reactions. A gas-filled-type recoil separator has been used for collecting evaporation residues of the reactions separating them from high intensity beam particles. The reactions studied were ²⁰⁸Pb(⁵⁸Fe,n)²⁶⁵Hs, ²⁰⁸Pb(⁶⁴Ni,n)²⁷¹Ds, ²⁰⁹Bi(⁶⁴Ni,n)²⁷²Rg, ²⁰⁸Pb(⁷⁰Zn, n) ²⁷⁷112, and ²⁰⁹Bi(⁷⁰Zn,n)²⁷⁸113. In studies of the first four reactions we have provided the independent confirmations of the productions and their decays of the isotopes, ²⁶⁵Hs, ²⁷¹Ds, ²⁷²Rg, and ²⁷⁷112, as well as the decay properties of their decay daughters, previously studied by Hofmann et al., a group of Gesellschaft für Schwerionenforschung (GSI), Germany. In the last reaction, we observed two decay chains originated from the isotope ²⁷⁸113, assigned firstly by generic correlation of the alpha decay chains connected into the previously known decay of ²⁶⁶Bh and ²⁶²Db via previously unknown alpha decays of ²⁷⁸113, ²⁷⁴Rg and ²⁷⁰Mt.     

Transfer reaction studies to states in 14N and 14C

States in ¹⁴N and ¹⁴C have been populated by the Li-induced reactions ¹⁰B(⁶Li, d), ¹¹B(⁶Li, t/³He), ¹¹B(⁷Li, α), ¹²C(⁶Li, α), and ¹³C(⁷Li, ⁶He/⁶Li) at E_Li = 32 and 34 MeV. Selective population of states is observed with these reactions. Angular distributions were measured for the ¹¹B(⁶Li t/³He) analog reactions. Experimental criteria are developed to allow the identification of analog states up to 18.40 and 16.45 MeV excitation in ¹⁴N and ¹⁴C, respectively.     

Infrared spectrum of CS2: “Hot” bands associated with the 2185 cm−1 band and evidence for the CS2 laser assignment

The 10⁰100⁰0 band of CS₂ has been measured with a resolution of 0.030 cm^?1. The following “hot” bands associated with this transition were also measured and analyzed: 11¹101¹0, 12⁰102⁰0, 12²102²0, 13³103³0, 20⁰110⁰0, 30⁰120⁰0, 21¹111¹0, and 22⁰112⁰0. In addition, the 10⁰100⁰0 bands of the isotopic species ¹³C³²S₂, ¹²C³²S³³S, and ¹²C³²S³⁴S were measured in natural abundance. With the results of these measurements it is shown that the 02⁰112⁰0 transitions do indeed coincide with the CS₂ laser transitions, as do the 00⁰110⁰0 transitions. New arguments are given favoring the latter assignment.     

High-resolution infrared spectroscopy of NNO and NNO in the 1200–3500 cm region

We present a continuation of our investigation of the second most abundant isotopic species of nitrous oxide, ¹⁴N¹⁵N¹⁶O and ¹⁵N¹⁴N¹⁶O, in the infrared (IR). Our two previous contributions looked at the 3500–9000 cm⁻¹ region for ¹⁴N¹⁵N¹⁶O and ¹⁵N¹⁴N¹⁶O, respectively, in the 3500–9000 cm⁻¹ region. The use of highly enriched isotopologue samples in this study allowed us to go further into the IR, down to 1200 cm⁻¹. A total of 2 2742 transitions have been assigned based on the effective Hamiltonian model, with 108 of them being reported here for the first time. Rovibrational analyses of 98, 101, 8, 3, 6, 1 and 1 bands for the ¹⁴N¹⁵N¹⁶O, ¹⁵N¹⁴N¹⁶O, ¹⁵N¹⁵N¹⁶O, ¹⁴N¹⁵N¹⁸O, ¹⁵N¹⁴N¹⁸O, ¹⁴N¹⁵N¹⁷O and ¹⁵N¹⁴N¹⁷O isotopologues, respectively, were also performed.     

Excitation functions for 44Sc, 46Sc, and 47Sc radionuclides produced in the interaction of 45Sc with deuterons and 6He

Experimental excitation functions are presented for ⁴⁵Sc(d, p)⁴⁶Sc, ⁴⁵Sc(d, t)⁴⁴Sc, ⁴⁵Sc(⁶He, ⁵He*)⁴⁶Sc and ⁴⁵Sc(6He, α)⁴⁷Sc reactions at projectile energies near the Coulomb barrier. The obtained excitation functions for reactions ⁴⁵Sc(d, p)⁴⁶Sc and ⁴⁵Sc(⁶He, ⁵He*)⁴⁶Sc have similar behavior and have a maxima near the Coulomb barriers of these reactions. The compilation of the available experimental data, obtained at deuteron- and ⁶He-energies near the Coulomb barrier, showed that the values of the cross sections at the maxima of the excitation functions obtained in (d, p) reactions and the reactions for one-neutron pickup from the ⁶He projectiles have a different Z-dependence.     

Vibration-rotation bands of 14N15N16O15N14N16O: 1.6–5.7 μm region

The infrared Fourier spectrum of 63 bands of ¹⁴N¹⁵N¹⁶O and of 69 bands of ¹⁵N¹⁴N¹⁶O have been measured and analyzed from 1750 to 6000 cm^?1. The rotational constants are given for 20 Σ, 11 Π, 7 Δ, and 3 Φ levels of ¹⁴N¹⁵N¹⁶O and 21 Σ, 14 Π, 8 Δ, and 5 Φ levels of ¹⁵N¹⁴N¹⁶O. Two bands of the previously unreported isotopic species ¹⁴N¹⁵N¹⁷O and ¹⁵N¹⁴N¹⁷O have been observed. Several local resonances are present in the levels 31^1c0 and 04⁰1 in ¹⁴N¹⁵N¹⁶O; 10⁰1, 06⁰0, 11^1d1, 12⁰1 in ¹⁵N¹⁴N¹⁶O. In both isotopes two “forbidden” Δ-Σ transitions are observed: 04^2c0-00⁰0 and 12^2c0-00⁰0.     

Activation cross-sections of titanium isotopes at neutron energies of 13.5–14.8 MeV

The cross-sections for ~(46) Ti(n,2 n)~(45) Ti, ~(46) Ti(n,p)~(46 m+g) Sc+~(47) Ti(n,d*)~(46 m+g) Sc, ~(46)Ti(n,p)~(46 m+g) Sc, ~(47) Ti(n,p)~(47) Sc+~(48) Ti(n,d*)~(47) Sc, ~(47) Ti(n,p)~(47) Sc, ~(48) Ti(n,p)~(48) Sc+~(49) Ti(n,d*)~(48) Sc,~(48) Ti(n,p)~(48) Sc, and ~(50) Ti(n,α)~(47) Ca reactions were investigated around neutron energies of 13.5–14.8 Me V by means of the activation technique. Fast neutrons were produced by the~3 H(d,n)~4 He reaction. Neutron energies from different directions in the measurements were obtained in advance using the method of cross-section ratios for ~(90) Zr(n,2 n)~(89 m+g) Zr and ~(93) Nb(n,2 n)~(92 m) Nb reactions. The results obtained are analyzed and compared with the experimental data provided by the literature and verified nuclear data in the JEFF-3.3,CENDL-3.1, ENDF/B-VIII.0 libraries, as well as results calculated by Talys-1.9 code.     

A study of three-nucleon transfer reactions on 17O

The reactions ¹⁷O(¹¹B, ⁸Li)²⁰Ne, ¹⁷O(¹²C, ⁹Be)²⁰Ne and ¹⁷O(¹³C, ¹⁰B)²⁰F have been studied using beams of 115 MeV ¹¹B and ¹²C and 105 MeV ¹³C incident on a gas target. Shell-model calculations have been performed for ²⁰Ne and ²⁰F, for comparison with the experimental data. It is found that the data can be interpreted using the shell model spectroscopic factors and a semi-classical reaction theory. We justify the use of the latter by applying it to the cases of three-nucleon transfer on ¹⁶O. Spin assignments are suggested for previously unidentified states in ²⁰F.     

The microwave spectrum of HGeCl

The J = 1₀₁-0₀₀ and 2₀₂-1₀₁ transitions of nine isotopomers of chlorogermylene, H⁷⁴Ge³⁵Cl, H⁷⁴Ge³⁷Cl, H⁷²Ge³⁵Cl, H⁷²Ge³⁷Cl, H⁷⁰Ge³⁵Cl, H⁷⁰Ge³⁷Cl, H⁷⁶Ge³⁵Cl, H⁷⁶Ge³⁷Cl, and H⁷³Ge³⁵Cl are measured at 8-9 and 16-18 GHz. The effective rotational constants, the nuclear quadrupole coupling constants of ³⁵Cl, ³⁷Cl, and ⁷³Ge, and the nuclear spin-rotation coupling constants of ³⁵Cl and ³⁷Cl are determined.