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Many jets are detected at X-ray wavelengths in the Sun's polar regions, andthe ejected plasma along the jets has been suggested to contribute mass to thefast solar wind. From in-situ measurements in the magnetosphere, it has beenfound that the fast solar wind has photospheric abundances while the slow solarwind has coronal abundances. Therefore, we investigated the abundances of polarjets to determine whether they are the same as that of the fast solar wind. Forthis study, we selected 22 jets in the polar region observed by Hinode/EIS (EUVImaging Spectrometer) and XRT (X-Ray Telescope) simultaneously on 2007 November1-3. We calculated the First Ionization Potential (FIP) bias factor from theratio of the intensity between high (S) and low (Si, Fe) FIP elements using theEIS spectra. The values of the FIP bias factors for the polar jets are around0.7-1.9, and 75$\%$ of the values are in the range of 0.7-1.5, which indicatesthat they have photospheric abundances similar to the fast solar wind. Theresults are consistent with the reconnection jet model where photosphericplasma emerges and is rapidly ejected into the fast wind.

Photospheric Abundances of Polar Jets on the Sun Observed by Hinode