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We performed high-resolution optical spectroscopy and X-ray observations ofthe recently identified Mira-type symbiotic star EF Aql. Based onhigh-resolution optical spectroscopy obtained with SALT, we determine thetemperature ($\sim $55 000 K) and the luminosity ($\sim$ 5.3 $L_\odot$) of thehot component in the system. The heliocentric radial velocities of the emissionlines in the spectra reveal possible stratification of the chemical elements.We also estimate the mass-loss rate of the Mira donor star. Our Swiftobservation did not detect EF Aql in X-rays. The upper limit of the X-rayobservations is 10$^{-12}$ erg cm$^{-2}$ s$^{-1}$, which means that EF Aql isconsistent with the faintest X-ray systems detected so far. Otherwise wedetected it with the UVOT instrument with an average UVM2 magnitude of 14.05.During the exposure, EF Aql became approximately 0.2 UVM2 magnitudes fainter.The periodogram analysis of the V-band data reveals an improved period of320.4$\pm$0.3 d caused by the pulsations of the Mira-type donor star. Thespectra are available upon request from the authors.

Optical spectroscopy and X-ray observations of the D-type symbiotic star EF Aql