Comparison of the Fe-57 hyperfine interactions in silicate phases in Saricicek howardite and some ordinary chondrites

International Conference on Hyperfine Interactions and their Applications (HYPERFINE) -- FEB 10-15, 2019 -- INDIAWOS: 000467083400005Silicate crystals have different thermal history in non-differentiated and differentiated meteorites. This leads to some differences in the Fe2+ and Mg2+ distribution between the M1 and M2 sites in olivine, orthopyroxene and clinopyroxene crystals in stony meteorites resulting in small variations in the Fe local microenvironment. For this reason, a comparison of Mossbauer hyperfine parameters for the Fe-57 in the M1 and M2 sites in orthopyroxene and Ca-rich clinopyroxene for non-differentiated NWA 6286 LL6, NWA 7857 LL6 and Tsarev L5 ordinary chondrites and differentiated Saricicek howardite was carried out. The results obtained demonstrated small variations in quadrupole splitting and isomer shift for the studied non-differentiated and differentiated stony meteorites.Ministry of Science and Higher Education of the Russian Federation [3.1959.2017/4.6]; Act 211 Government of the Russian Federation [02.A03.21.0006]; Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [MFAG/113F035]The authors wish to thank G.A. Yakovlev and Dr. M.S. Karabanalov for the help with scanning electron microscopy with energy dispersive spectroscopy. This work was supported by the Ministry of Science and Higher Education of the Russian Federation (the Project No 3.1959.2017/4.6) and Act 211 Government of the Russian Federation, contract No 02.A03.21.0006. O.U. acknowledges the Scientific and Technological Research Council of Turkey (the Project number: MFAG/113F035)