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The emission from KCI:Sb 3 + and KI:Sb 3 + excited in the A-absorption band was measured as a function of exciting photon energy and temperature. The A-band excitation produced two emission bands for KCI:Sb 3 + and a single band for KI:Sb 3 + . The definitive assignment of these bands is presented in terms of the adiabatic potential energy surface (APES), in which the effect of the spin-orbit interaction (SO) on the Jahn-Teller (JT) interaction coupling to the Eg mode is taken into account. The polarization spectrum and the angular dependence of polarization ratio of the A -band emission were also studied to determine the symmetry axes of the Sb 3 + -vacancies complex. The results indicate that the anisotropy is associated with the relaxed excited state (RES) ofSb 3 + . It is also found that the JT interaction coupling to the T 2g mode and the vacancies, situated in the next-nearest-neighbor (nnn) and the nearestneighbor (nn) positions to the Sb 3 + ion, give rise to an additive perturbation.

For the purpose of radiation protection, the reference neutron field for calibration of neutron monitors was constructed using radioactive neutron sources-bare-(252)Cf, D(2)O-moderated (252)Cf and (241)Am-Be(alpha,n)-at Korea Research Institute of Standards and Science (KRISS). The well-specified neutron source with its emission rate and the anisotropy was installed at the centre of the neutron irradiation room, which is 6.6 x 7.6 x 6.3 m(3) in size. The neutron spectra of each source was measured using the Bonner sphere spectrometer (KRISS-BSS). Calculations using MCNP5 with realistic geometry and materials in the neutron irradiation room were performed. The calculations and measurements were found to be in good agreement, showing that the neutron calibration facility at KRISS is well established.

Section III (neutron measurements) of the Comité Consultatif des Rayonnements Ionisants, CCRI, conducted a key comparison of primary measurements of the neutron emission rate of an 241 Am-Be(α,n) radionuclide source. A single 241 Am-Be(α,n) source was circulated to all the participants between 1999 and 2005. Eight laboratories participated-the CIAE (China), CMI (Czech Republic), KRISS (Republic of Korea), LNMRI (Brazil), LNE-LNHB (France), NIST (USA), NPL (UK), and the VNIIM (Russian Federation)-with the NPL making their measurements at the start and repeating them near the end of the exercise to verify the stability of the source. Each laboratory reported the emission rate into 4π sr together with a detailed uncertainty budget. All participants used the manganese bath technique, with the VNIIM also making measurements using an associated particle technique. The CMI, KRISS, VNIIM, and later the NPL, also measured the anisotropy of the source although this was not a formal part of the comparison. The first draft report was released in May 2006 and having been discussed and modified by the participants and subsequently reviewed by the CCRI(III), the present paper is now the final report of the comparison.

Correction equations of the coincidence-summing effect for efficiencies of HpGe detector based on the decay scheme were developed by considering the summing up to triple coincidence. The correction equations which do not dependent on the kind of the Ge detector are very useful for efficiency calibrations of a Ge detector in the energy region from 60 to 400 keV by using 75Se radionuclide even with very short source-to-detector distances.