[en] This evaluation was completed in May 2011, and the literature available at this date has been included here. ²²⁹Th is a member of the ²³³U decay series. This was recognized by Hagemann et al. (1947Ha02). ²³³Th β^- decay → ²³³Pa β^- decay → ²³³U α decay → ²²⁹Th. Decay Scheme: ²²⁹Th is a part of the 4n+1 series of Neptunium decay chain which decays 100% by the emission of α particles to the ground and the excited states in ²²⁵Ra. 5 (1)% populates the ground state of ²²⁵Ra. Important impurities in the production of ²²⁹Th are U-238 and U-232. The decay scheme is reasonably complete and consistent. Its overall consistency is verified by the comparison between Q(calc), deduced from the evaluated average energies of all emissions, and Q(alpha) from the atomic mass evaluation of Audi et al. (2003Au03). A percentage deviation between Q(calc) and Q(alpha) is 0.32%. There are, however, 26 unplaced gamma rays observed in this decay scheme. The level energies, spins, parities along with the multipolarities and mixing ratios of the γ-rays presented in this evaluation are from 2009Ja03

[en] Evaluated: June 2011. This evaluation was completed in June 2011, and the literature available at this date has been included here. ²³³U is usually produced by n-capture on 232Th and subsequent beta-decays of ²³³Th and ²³³Pa. That is ²³²Th(n,γ) → ²³³Th →²³³Pa → ²³³U. The samples used in various measurements were several years (∼20 years) old and generally enriched to 99.9%. The impurities may come from ²³²U (T_1/2 = 70 y) produced by the ²³³U(n,2n) reaction during the ²³²Th target irradiation in the reactor. However, radiochemical separation was performed before measurements in almost all of the published reports. Decay Scheme: ²³³U is part of the 4n+1 series of the Neptunium decay chain which disintegrates almost entirely by alpha decay to about 50 excited levels including the ground state of ²²⁹Th. A very small amount (6 x 10^-11%) disintegrates by spontaneous fission. The level energy of the isomeric 3/2⁺ 1^st excited state has been taken from the recent highly precise measurement of Beck et al. (2007Be16). Many investigations were carried out of this unusually low nuclear excited state. In a recent work (2011), Campbell et al. (2011Ca17) explored the possibility of optical excitation of this nuclear state and produced laser-cooled crystals of triply charged ²²⁹Th in a linear Paul trap. A new value of nuclear electric quadrupole moment Q = 3.11(16) eb was deduced by them. The decay scheme is reasonably complete and consistent. Its overall consistency is verified by the comparison between Qcalc (4908.5 ± 1.2 keV) deduced from the evaluated average energies of all emissions, and Qalpha (4893 ± 2 keV) from the atomic mass evaluation of Audi et al. (2003Au03). The percentage deviation between Q_calc and Q_alpha is 0.4 ± 0.6%. There are, however, 44 unplaced gamma rays observed in this decay scheme. The level energies, spins, parities along with the multipolarities and mixing ratios of the γ-rays presented in this evaluation are from 2008Br17

[en] There are several methods for the measurements of beta delayed neutron emission probabilities (P_n), which is given by the ratio of number of beta-delayed neutron decays to the total number of beta decays i.e N_n/N_β. Therefore, this involves the measurements of beta, neutron and gamma depending on the method. The experimental facilities available at the Variable Energy Cyclotron Centre, Kolkata, India has been presented in the light of the possible measurements of beta delayed neutron emission probability

[en] Good and reliable nuclear data are the backbone for both applied and basic research in nuclear physics. The nuclear data have a very wide range and are obtained through precise measurements and detection of charged particles, neutrons and gammas. Many laboratories generate such data with varying precision and accuracy. These data need to be evaluated so that the end user gets a reliable value to be used for application. The evaluation also helps to assess the need of further measurements. (author)

[en] Spectroscopic studies of the neutron rich nuclei gained momentum by the development of the radioactive ion beam (RIB) facilities and the new generation of detection techniques around the world. The RIB facility at GANIL along with the high acceptance spectrometer VAMOS coupled to high efficiency, highly segmented gamma detector array EXOGAM makes an ideal combination to study the detailed spectroscopy of the neutron rich nuclei around N = 20 in the so called Island-of-inversion. An experiment, with this setup, has been performed with cocktail radioactive beam to study the spectroscopy of the neutron rich even-even, odd-p, odd-n and odd-odd nuclei around N = 20 in the island-of-inversion. The new results obtained in the present measurement have been discussed. (author)

[en] The energy level systematics of the γ-soft nuclei at mass ∼70 region have been reviewed. Lifetimes of the high spin levels in ⁷³Se and ⁷⁵Br have been measured by DSAM method. The experimental data have been analysed in terms of a triaxially deformed Woods-Saxon potential

[en] Details of the evaluation of ²³³U were described, which is now almost complete following the review process. Many experimental measurements have been made for this radionuclide, which undergoes effectively 100% α decay to ²²⁹Th, with very minor spontaneous fission and cluster branches. A consistent set of measurements for the total half-life allow a weighted mean with a reduced _² of 0.39 to be calculated, whereas for the spontaneous fission branch only a lower limit has been consistently measured. A complex decay scheme has been produced containing fifty-three levels in the ²²⁹Th daughter, with 267 γ rays and thirty-one α-particle transitions. An energy value of 7.6(5) eV has been determined for the very low-lying level in ²²⁹Th following work published in 2007 (2007Be16). A good Q-value balance is obtained from the decay scheme that compares well with the recommended value of Audi et al. Work on the decay of ²²⁹Th is in the early stages, with the literature survey complete and an initial set of nuclear levels formulated. Work will also be undertaken with F.G. Kondev on ²⁰⁹Tl and ²⁰⁹Pb in conjunction with his ENSDF mass chain evaluation for A = 209

[en] The case of a domain wall of finite thickness is examined by use of two different expressions for the energy-stress tensor of domain walls but no symmetry condition. It is found that the equations of general relativity show that such walls cannot be in static equilibrium, and further even nonequilibrium walls can be consistent with Einstein's equations only under very special circumstances

[en] A quadratic relation between the red shift and distance as has apparently emerged from the analysis of Nicoll and Segal (1978. Proc. Nat. Acad. Sci. (USA), 75,535 and Ann. Phys. (USA), 113,1.), may be consistent with relativistic cosmology if the present deceleration parameter has a high value and the Hubble constant a low value. Consequences of these are worked out. (author)

[en] A microscopic description of the recent data on the Coulomb form factors for the Osub(gnd)⁺→2₂⁺ transitions in the nuclei ⁴⁸Ti and ⁵⁰Cr is attempted in terms of the prolate and oblate intrinsic states resulting from realistic effective interactions operating in the 2p-1f shell. The results for the higher momentum-transfer region show dramatic improvements compared to the form factor estimates obtained in some recent shell model calculations involving the fsub(7/2)sup(n)+fsub(7/2)sup(n-1)psub(3/2) configurations. (author)