[en] We present an analysis of the decays B⁰ → K*⁰(892)γ and B⁺ → K*⁺(892)γ using a sample of about 383 million B(bar B) events collected with the BABAR detector at the PEP-II asymmetric energy B factory. We measure the branching fractions Β(B⁰ → K*⁰γ) = (4.47 ± 0.10 ± 0.16) x 10^-5 and Β(B⁺ → K*⁺γ) = (4.22 ± 0.14 ± 0.16) x 10^-5. We constrain the direct CP asymmetry to be -0.033 < Α(B → K*γ) < 0.028 and the isospin asymmetry to be 0.017 < Δ_0- < 0.116, where the limits are determined by the 90% confidence interval and include both the statistical and systematic uncertainties.

[en] In this study, the decay form of ⁹⁹Mo which is supplied by KAERI had been investigated from the analysis of γ-ray energy spectrum radiating from the radioactive element ⁹⁹Mo. The γ-ray energy spectrum was obtained using NaI(T1) scintillation detector and multichannel pulse height analyser. The calibration curve and formula for γ-ray energy versus channel number were made from the two photopeaks of standard radioactive source ²²Na, 140 and 314 channel corresponding to the γ-ray energy of 511 keV and 1275 keV, respectively. The γ-ray energies from ⁹⁹Mo were detected at the same condition with the standard source, and compared with standard energies of ⁹⁹Mo. Experimental results show that the γ-ray energies from the sample are in good agreement with the values of standard source within energy error of 2 keV, which means that the ⁹⁹Mo supplied by the KAERI can be used as a standard radioactive source. (Author)

[en] Using a silica aerogel sample with oxygen gas filled as the positronium (Ps) source and a time selecting energy spectrometer as the equipment, the γ energy from the para-positronium (P-Ps) 2γ decay has been determined as 510995.3 (1.2) eV by a comparison with the precise γ energy 511852.7 (0.8) eV of ¹⁰⁶Ru. The results are useful for measuring the mean γ energy or the γ energy of each lifetime component of positron annihilation in materials

[en] The influence of the measurement apparatus on the γ-decay of coherent rotational states is discussed. It is shown that the mathematical procedure, which has been devised to describe the decay of an unstable particle characterized by a unique quantum state, applies, with suitable changes, also to this case. For very small times, the decay probability still shows the pulses discussed in a previous paper where the influence of the environment was not taken into account. For large times, the interaction with the environment enforces a superposition of exponentials for the decay probability. (author)

[en] High-quality evaluated nuclear and atomic data are needed in applied research and detector calibrations. Using inaccurate gamma-ray emission probabilities may result in tremendous miscalculations, which, in the power reactor industry, could involve large amounts of radioactive material. Similarly, for isotopes used in nuclear medicine, a wrong radiation dose could have serious consequences on the patient's health. For detector calibrations, the effect of inaccurate standards may be propagated to actual measurements, thus producing incorrect results that are often difficult to identify. For these reasons, nuclear scientists from France, Germany, the United Kingdom, and the United States have joined their efforts to evaluate decay data for radionuclides specifically used in applied research and detector calibrations. The evaluation of the relevant data requires the application of uniform and well-defined procedures, Common sources of additional (theoretical) values are used for testing and verifying the total balance of radiation emission probabilities in decay schemes. It is important to have special care when combining results measured with different standards and to apply a single and realistic statistical procedure for averaging discrepant data. The collaboration has adopted the limitation of relative statistical weight method and a computer program for this purpose. The evaluations, which will be published as laboratory reports, will also be submitted to the Nuclear Data Section of the International Atomic Energy Agency, and to the National Nuclear Data Center, Brookhaven National Laboratory, for inclusion in their respective databases

[en] The radiative capture process of the "1"2C+"1"2C and "1"2C+"1"6O reactions has been studied using the very selective 0° Dragon spectrometer at Triumf and its associated BGO γ-array. The experiments have been performed at energies around the Coulomb barrier where resonances in the process have been reported. Our results show previously unobserved γ-decay to doorway states in the "2"4Mg and "2"8Si respectively around 10 to 12 MeV. The nature of the states is discussed and two scenarios are proposed. (author)

[en] We show how to search for radiative decays of Solar neutrinos, whose signature is a photon emitted in the visible energy range. The search may be done using either Solar or Lunar eclipses. Using the total Solar eclipse of October 24, 1995 no signal has been found and a limit on the lifetime corresponding to the radiative decay process is presented. (author)

[en] Using an anti-Compton spectrometer, the gamma ray spectrum of ^166mHo was remeasured with the aim to reveal new Low-intensity gamma transitions since ^166mHo is a recommended calibration standard for Ge(Li) or HPGe detectors. Altogether, 61 gamma transitions were assigned to the ^166mHo decay. All of them were established in the decay scheme. (author). 2 figs., 2 tabs., 16 refs

[en] Nuclear γ-decays supply one of the classical tests of time reversal symmetry. The decay investigated is the E2-M1 mixed 122 keV line in ⁵⁷Fe. The experiment has been done in 1977 at CALTECH and not been analysed up to now. The shell model has been used as a framework for the analysis presented here. To find possible candidates that might further restrict the limits reached by nuclear γ-decay experiments criteria for a systematic search through the nuclear data sheets are given

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