Astronomy & Astrophysics

Table 1: Observing log for the three Chandra ACIS-S observations of V410 Tau. Rotational phases are computed using the new ephemeris given in Table 2. Values refer to the 0.2-8 keV energy band.
Table 2: Ephemeris of V410 Tau: value by P94 and our update.
Table 3: X-ray spectral parameters of V410 Tau derived from a joint fit to the three ACIS observations that represent the stars' quiescent state. A constant normalization factor was applied to allow for the observed difference in X-ray brightness between the three data sets: $N_{\rm 200190} = 1$ , $N_{\rm 200191} = 0.91 \pm 0.04$ , $N_{\rm 200130} = 0.74 \pm 0.04$ . Errors are 90% confidence levels.
Table 4: X-ray and H $\alpha$ flux and respective luminosities of V410 Tau during the campaign in November 2001. X-ray emission was measured in the 0.4-8 keV energy interval.