The characteristics of heavy ion tracks in phosphate glasses after irradiation under various temperature conditions are presented. Calibration experiments are performed to obtain the dependence of ...the parameters of the etched tracks on the sample heating temperature and time and on the moment of heating a sample in relation to irradiation and etching. To effectively identify the ion charges, the stability of reproducing the optimum chemical etching conditions (etching chemical solution composition, concentration, etching time) is strictly observed in processing irradiated glasses. The results obtained allow us to conclude that phosphate glasses can be effectively used to detect and identify the superheavy nuclei synthesized at the Factory of Superheavy Elements of the Joint Institute for Nuclear Research (JINR).
Two independent methods: Asymptotic Normalization Coefficients (ANC) and Modified Diffraction Model (MDM) were applied to new and existing experimental data to search for states with enhanced radii ...in isobaric analogue states (IAS) of 12B and 12N. The ANC analysis of the 11B(d,p)12B reaction at Ed = 21.5 MeV has confirmed neutron halo existence for two states of 12B: 2−, 1.67 MeV and 1−, 2.62 MeV 1. Some new results were obtained for higher excited states: halo-like states were observed for 0+, 2.72 MeV and 3−, 3.39 MeV states. It should be mentioned that the last one is unbound state, which is 19 keV above the neutron emission threshold and in both states last neutron has a non-zero orbital momentum (ln=1 and ln=2 correspondingly). We propose to use MDM to study isobaric analogue states of 12B in the mirror 12N nucleus and apply it to analyze the (3He,t) reaction data. The existing in the literature data are not completed enough to make definite conclusion about halo in the 2− and 1− states of 12N. This fact simulated us to carry out a new experiment on the 12C(3He,t)12N reaction at the end of 2018. The measurements were conducted at the University of Jyväskylä (Finland) using the K130 cyclotron to produce a 3He beam at E(3He)=40 MeV. The differential cross sections of the 12C(3He,t)12N reaction were measured in the c.m. angular range 8°-70°. Preliminary results for angular distributions are obtained. MDM analysis of preliminary (3He,t) experimental data is done.
The differential cross sections for the
12
C(
3
He,
t
)
12
N reaction leading to formation of the 1
+
(ground state), 2
+
(0.96 MeV), 2
−
(1.19 MeV), and 1
−
(1.80 MeV) states of
12
N are measured at
...E
(
3
He) = 40 MeV. The analysis of the data is carried out within the modified diffraction model and distorted wave Born approximation. Increased rms radii have been obtained for the ground, 2
−
(1.19 MeV), and 1
−
(1.80 MeV) states. We revealed that
12
B,
12
N, and
12
C in the isobaric analogue states with
T
= 1, and spin-parities 2
−
and 1
−
have increased radii and exhibit properties of neutron and proton halo states.
The paper is devoted to the neutron-physical parameters obtained via combined calculations and experimental measurements for the exit of the WWR-K reactor beam tube. The experimentally measured ...values of the thermal and fast neutron flux densities at the exit comprise 9.6 × 108 and 8.4 × 107 cm-2 s-1 , respectively. The dose rate of gamma-emission is 30 Sv/h. The obtained parameters will be used in designing of the collimation and screening systems of the installation for radiography and tomography to be created at the beam tube #1.
GaAs Schottky barrier detectors for α particle spectrometry have been tested. Detectors had an input window area of 80 mm
2
and a working barrier layer thickness of 40–50 μm. The energy resolution ...(FWHM) measured on 5.499 MeV α line of
238
Pu source amounted to 17.5 keV at a generator peak width of 7.8 keV. In the measurements on a
226
Ra source, detectors showed linear response and nearly 100% charge collection efficiency at reverse bias above 65 V for all energies of α particles emitted from the source. Tests for thermal stability showed that the proposed detectors can be used in alpha-spectrometry of radionuclides at temperatures up to 120°C.
A new measurement of differential cross sections for elastic psup.6Li scattering in the energy range 0.35-1.2 MeV was performed. A partial-wave analysis of the data obtained in this way was carried ...out, and potentials simulating the psup.6Li interaction were constructed. Various experiments devoted to studying elastic psup.6Li scattering over the broad energy range of 0.5-50 MeV were analyzed on the basis of the optical model. By using the potentials obtained from the partial-wave analysis, the possibility of describing the astrophysical S factor for radiative proton capture on sup.6Li at low energies was considered within the potential cluster model involving forbidden states.
Within the framework of the modified potential cluster model with classification of orbital states according to the Young schemes, the possibility of describing experimental data for the ...astrophysical S-factor of psup.15N radiative capture at energies from 50 to 1500 keV is considered. It is shown that on the basis of Ml and E1 transitions from various psup.15N scattering states to the ground state of the sup.16O nucleus in the psup.15N channel it is entirely possible to successfully explain the overall behavior of the S-factor in the considered energy region in the presence of two resonances. Keywords: nuclear physics, light atomic nuclei, low energies and astrophysical energies, elastic scattering, psup.15N system, astrophysical S-factor, potential description, radiative capture, total cross sections, thermonuclear reactions, primordial nucleosynthesis, potential cluster model, forbidden states, classification of orbital states according to the Young schemes.
Existing experimental data on elastic and inelastic deuteron scattering on sup.6Li nuclei in the energy range from 8 to 50 MeV were analyzed within the approach of coupled reaction channels. The ...coupling of elastic scattering and inelastic scattering accompanied by the transition to the 3.sup.+ state at E.sub.x = 2.186 MeV and the mechanism involving the exchange of an alpha-particle cluster were taken into account in respective calculations. The phenomenological potentials obtained from the present analysis describe well experimental angular distributions at all energies and in full angular ranges. The depths of the real and imaginary parts of the potentials in question depend smoothly on energy at fixed values of the remaining parameters. The energy dependence of relevant volume integrals agrees well with similar data for the p + sup.6Li, α + sup.6Li, and sup.12C + sup.12C systems and with the predictions of a microscopic theory.
The mass-energy distributions and cross sections of proton-induced fission of
232
Th have been measured at the proton energies of 7, 10, 13, 20, 40, and 55 MeV. Experiments were carried out at the ...proton beam of the K-130 cyclotron of the JYFL Accelerator Laboratory of the University of Jyväskylä and U-150m cyclotron of the Institute of Nuclear Physics, Ministry of Energy of the Republic of Kazakhstan. The yields of fission fragments in the mass range
A
= 60–170 a.m.u. have been measured up to the level of 10−4%. The three humped shape of the mass distribution up has been observed at higher proton energies. The contribution of the symmetric component grows up with increasing proton incident energy; although even at 55 MeV of proton energy the shoulders in the mass energy distribution clearly indicate the asymmetric fission peaks. Evolution of shell structure was observed in the fission fragment mass distributions even at high excitation energy.
We present the results of measurements and analysis of the differential cross sections of the 11B(d, p)12B reaction leading to formation of the 1+ ground state and the 0.953-MeV 2+, 1.674-MeV 2−, ...2.621-MeV 1−, 2.723-MeV 0+, 3.389-MeV 3− excited states of 12B at Ed = 21.5 MeV. The analysis of the data was carried out within the coupled-reaction-channels method for the direct neutron transfer and the Hauser-Feshbach formalism of the statistical compound-nucleus model. We deduced the spectroscopic factors, asymptotic normalization coefficients, and rms radii of the last neutron in all states studied. The existence of the neutron halos in the 1.674-MeV 2− and 2.621-MeV 1− states was found in consistence with the earlier published data. New information about the enlarged rms radii (6.5 fm) of the last neutron in the unbound 3.389-MeV 3− states of 12B was obtained, which may indicate the evidence of the neutron halo with the orbital momentum of the last neutron equal to two.
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![Radiative p[sup.15]N captur...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1064-8887/small "Radiative p[sup.15]N capture in the region of astrophysical energies")
