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tokens: and denote the median of each band in the observed spectrum and model, and gives the standard deviation in each band in the observed spectrum. As also described in Manara et al. (2013a) , this does not represent a true distribution as the noise in the template spectrum is neglected. The models are visually compared to confirm that the best-fit model matches the observed spectrum. The uncertainties are estimated from the range of UV-excess fluxes spanned by models that yield a similar -like value as the best-fit model and match the spectrum visually (details are described in Sect. 4.3 ). Table 5 Parameter ranges of the hydrogen slab model. The measured UV-excess flux is converted to accretion luminosity (). The mass accretion rates () are then calculated byunder the assumption that gas accretes from the disk truncation radius in free-fall onto the star, where is adopted for consistency with pre-existing measurements (see review by Hartmann et al. 2016 ). Table 6 Mass accretion properties in the Cha association. Notes. Columns 2–7 list equivalent widths (EW), accretion luminosity (; using conversions from Alcalá et al. 2014 ), and mass accretion rates () for H and H, respectively. The last two columns list and determined from UV excess. 4.3. Description of fits and uncertainties Figures A.1 – A.4 show the best-fit model for each object. The values of and are listed in Table 6 . Uncertainties in the accretion rates are introduced by uncertainties in the stellar parameters, the distance, and in the individual fits (see, e.g., Herczeg Hillenbrand 2008 ; Manara et al. 2013a ). For our sample, uncertainties in are 0.3 dex. Weak accretors, such as RECX 11, have uncertainties of 0.5 dex because the excess is fainter than the photosphere, thereby increasing the uncertainty in bolometric correction. Upper limits on are difficult to estimate and depend on the ability to distinguish any excess emission from the underlying photospheric spectrum and on an uncertain bolometric correction. In order to estimate upper limits of for non-accreting objects, we perform a similar model fit as described above. The upper limits are compared to the detections in Fig. 8 a in terms of the ratio of . For K stars, the upper limit of for non-accreting stars is similar to of RECX 11. For M stars, the upper limits are almost uniform at (see also Manara et al. 2013b ), with the exception of RECX 12 (). Fig. 7 As in Fig. 6 . J0843, J0844, RECX 5 and RECX 9 show clear indications of UV-excess. For RECX 11, a slight excess is seen. Comments on each fit to the spectra of accreting objects are provided below. <italic>J0843 and J0844</italic>: due to the pronounced observed Balmer jump and strong excess in the Balmer and Paschen continua, the slab model parameters and therefore the are well constrained. Models using templates within 0.5 spectral subclasses yield accretion rates that agree to within 10% of these values. <italic>RECX 5</italic>: the best-fit is calculated using the M4