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tokens: WDs should have lower Ṁ than novae with lighter WDs. The fact that heavier WD novae require a smaller total accreted mass to ignite the thermonuclear explosion ( Shara et al. 2010 ; Glasner Truran 2009 ; Yaron et al. 2005 ) does not seem to provide any insight into how this would control Ṁ between OBs. Furthermore, while binaries with massive WD and high Ṁ may “disappear” from the diagram because they become common envelope systems ( Nomoto 1982 ), there appears to be no obvious way to hide the other missing M WD − Ṁ combinations (unless they become other kinds of CVs?). A tempting speculation, if this distribution is confirmed, is that the strip populated by the old novae discussed here may define the range of Ṁ and t 3 values where novae can occur. Observational Ṁ determinations for more (old) novae are clearly needed before exploring this idea any further. 12.5. Correlation between <italic>Ṁ</italic> and OB amplitude An interesting correlation exists between the OB amplitude and Ṁ (see Fig. 6 ) that associates large amplitude to low Ṁ . In hindsight, this is not completely surprising given the correlation between and Ṁ reported in Sect. 12.1 . Unlike that correlation, which requires knowledge of several physical parameters (distance, inclination, etc.), this one has as independent variable: the observed OB amplitude (i.e., the difference between two apparent magnitudes). Fig. 6. Correlation between accretion rate and the OB amplitude. Top panel : Ṁ computed using individual WD masses. Bottom panel : Ṁ computed using M WD = 1 M ⊙ for each nova. That the correlation exists without the correction for inclination is somewhat surprising, and may be due to the fact that for most of our novae the correction is relatively small. This would also explain why DQ Her, the nova in the sample with the largest i correction, appears as an outlier in Fig. 6 . Nevertheless, this correlation provides a direct way to estimate Ṁ for any nova for which only the OB amplitude is known. Thus, the OB amplitude acts as a proxy for Ṁ , much in the way that t 3 does (see Sect. 12.4 ). It should be noted that Schmidtobreick Tappert (2015) suggested that novae with large OB amplitudes are candidates for low-mass-transfer-rate systems, but they assumed that the absolute magnitude of a nova explosion differs only slightly for different systems, unlike what is shown by the L / L Edd and the MMRD relations; see Figs. 1 and 2 . The fits in terms of the explicit observables, computed as described in Sect. 2.2 , are 13. Concluding summary The new and precise distances from Gaia , together with the data of Paper I and from the literature, allowed us do determine new system parameters for our sample of 18 old novae with UV data (e.g., M v max , , L OB / L Edd , , Ṁ ). The final values include a detailed treatment of the errors and their propagation and are summarized in Table 2 . Functional relations are provided in the text for all correlations (either revisited or new) presented