... region

Table 1 and Fig. 7 are only available in electronic form at http://www.aanda.org

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... five fields

The field L1495 around V410 Tau was observed twice; the two observations are labelled XEST-23 and XEST-24. The fields around T Tau, AA Tau and BP Tau (XEST-01, XEST-25 and XEST-28, respectively) were not used; these are outlying fields, containing only one known TMC member each in the cases of XEST-25 and XEST-28, and three known members, but far away from the rest of TMC, in the case of XEST-01.

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... stars

About half of the 121 detected known TMC members are protostars and CTTs.

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... diagram

Note that reasonable estimates of $A_{\rm V}$ are obtained from the color-color diagram if our sources show no significant IR excess; this is consistent with the finding that our sample could be dominated by WTTs.

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... time

The counts in each band depend on the spectral shape of the source, which is in general different for the various sources.

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...2005)

With respect to the solar photospheric values by Anders & Grevesse (1989), the adopted abundances are: C = 0.45, N = 0.788, O = 0.426, Ne = 0.832, Mg = 0.263, Al = 0.5, Si = 0.309, S = 0.417, Ar = 0.55, Ca = 0.195, Fe = 0.195, Ni = 0.195. The same set of abundances was used by Güdel et al. (2007a) to fit the spectra of known TMC members.

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... case

We expect at most about 20 false associations among the 226 (i.e. 347 minus 121 TMC members) X-ray sources with an IR counterpart within 3''.

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... discussion

The candidate XEST-03-028 with high probability of membership is among the faint sources without mass estimate; its position in the IR diagrams might indicate very high absorption and/or IR excess.

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...$0.02{-}1.2~M_{\odot}$)

The positions in the IR diagrams of the candidates XEST-07-005 and XEST-17-043 with high probability of membership could suggest for them a substellar mass.

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