Specific heat and thermal history of the Saricicek howardite
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Özet
Meteorites are excavated fragments from asteroid surfaces and planets, and determining their thermophysical properties is important since they contain valuable information about internal structures of their parent bodies. We investigated thermophysical properties of the Saricicek meteorite by differential scanning calorimetry (DSC), measuring phase transition temperatures, enthalpy changes and specific heat capacities of samples and thermogravimetric analysis (TGA), investigating weight change in a sample as a function of temperature or time. DSC results indicate that troilite alpha/beta and beta/gamma phase transition temperatures of the interior part of the meteorite were at 421.98 +/- 0.02 and 581.74 +/- 1.71 K, and troilite content of interior and crust parts of the meteorite were 0.28 and 0.02 wt%, respectively. Relict temperatures were calculated as 453 +/- 10, 465 +/- 17, and 588 +/- 55 K; specific heat capacities were measured as 779, 745, and 663 J kg(-1) K-1 at 300 K; and predicted as 568, 537, and 480 J kg(-1) K-1 at 200 K, for interior, edge, and crust, respectively. TGA results revealed that Saricicek's weight loss was 0.98% at 1170 degrees C, and water content and hydrogen abundance at 200-800 degrees C were 0.34% and 0.04%, respectively. Obtained results shed light on a thermal history of Saricicek's parent body and provide further knowledge on thermal alteration of 4 Vesta.