SIMBAD references

The flux ratio of Fe XXVI-Lyα to Fe XXV-Heα lines (I_7.0/I_6.7) is a sensitive indicator of the maximum temperature (T_max), and therefore the mass of white dwarf stars (M_WD) in cataclysmic variables (CVs). To examine and calibrate the theoretical I_7.0/I_6.7-T_max-M_WD relations, reliable measurements of T_max and I_7.0/I_6.7 are necessary. In this work, we conduct a thorough investigation of 3-50 keV X-ray spectra of 25 solar neighborhood magnetic and nonmagnetic CVs based on archival NuSTAR and Suzaku observations. The measured T_max are compared to the I_7.0/I_6.7 and M_WD. The results show that the sampled CVs closely follow the theoretical I_7.0/I_6.7-T_max relation. Moreover, all the M_WD estimated from I_7.0/I_6.7 are consistent with the dynamically measured ones. We conclude that I_7.0/I_6.7 can be used as a good diagnostic for T_max and M_WD in both magnetic and nonmagnetic CVs.