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We have analyzed optical spectra of 25 X-ray sources identified as potentialnew members of the Taurus molecular cloud (TMC), in order to confirm theirmembership in this SFR. Fifty-seven candidates were previously selected amongthe X-ray sources in the XEST survey, having a 2MASS counterpart compatiblewith a PMS star based on color-magnitude and color-color diagrams. We obtainedhigh-resolution optical spectra for 7 of these candidates with the SARGspectrograph at the TNG telescope, which were used to search for Li absorptionand to measure the Ha line and the radial and rotational velocities; 18low-resolution optical spectra obtained with DOLORES for other candidatemembers were used for spectral classification, for Ha measurements, and toassess membership together with IR color-color and color-magnitude diagrams andadditional information from the X-ray data. We found that 3 sources show Liabsorption, with equivalent widths of ~500 mA, broad spectral line profiles,indicating v sin i ~20-40 km/s, radial velocities consistent with those forknown members, and Ha emission. Two of them are classified as new WTTSs, whilethe EW (~ -9 Ang) of the Ha line and its broad asymmetric profile clearlyindicate that the third star (XEST-26-062) is a CTTS. Fourteen sources observedwith DOLORES are M-type stars. Fifteen sources show Ha emission; 6 of them havespectra that indicate surface gravity lower than in MS stars, and theirde-reddened positions in IR color-magnitude diagrams are consistent with theirderived spectral type and with PMS models at the distance of the TMC. TheK-type star XEST-11-078 is confirmed as a new member from the strength of itsHa emission line. Overall, we confirm membership to the TMC for 10 out of 25X-ray sources observed in the optical. Three sources remain uncertain.

Optical spectroscopy of X-ray sources in the Taurus molecular cloud: discovery of ten new pre-main sequence stars