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RT Cru belongs to the rare class of hard X-ray emitting symbiotics, whoseorigin is not yet fully understood. In this work, we have conducted a detailedspectroscopic analysis of X-ray emission from RT Cru based on observationstaken by the Chandra Observatory using the Low Energy Transmission Grating(LETG) on the High-Resolution Camera Spectrometer (HRC-S) in 2015 and the HighEnergy Transmission Grating (HETG) on the Advanced CCD Imaging SpectrometerS-array (ACIS-S) in 2005. Our thermal plasma modeling of the time-averagedHRC-S/LETG spectrum suggests a mean temperature of $kT \sim 1.3$ keV, whereas$kT \sim 9.6$ keV according to the time-averaged ACIS-S/HETG. The soft thermalplasma emission component ($\sim1.3$ keV) found in the HRC-S is heavilyobscured by dense materials ($> 5 \times 10^{23}$ cm$^{-2}$). The aperiodicvariability seen in its light curves could be due to changes in eitherabsorbing material covering the hard X-ray source or intrinsic emissionmechanism in the inner layers of the accretion disk. To understand thevariability, we extracted the spectra in the "low/hard" and "high/soft"spectral states, which indicated higher plasma temperatures in the low/hardstates of both the ACIS-S and HRC-S. The source also has a fluorescent ironemission line at 6.4 keV, likely emitted from reflection off an accretion diskor dense absorber, which was twice as bright in the HRC-S epoch compared to theACIS-S. The soft thermal component identified in the HRC-S might be anindication of a jet that deserves further evaluations using high-resolutionimaging observations.

Long-term X-ray Variability of the Symbiotic System RT Cru based on Chandra Spectroscopy