Young stellar group around Sh 2-295

We analysed multi-object spectroscopic data acquired with Gemini/GMOS to search for typical features of T Tauri stars (TTs) and to determine their spectral types. Lithium absorption line ({lambda} 6708{AA}) was used as a youth indicator, while H{alpha} emission was investigated to probe accretion activity. We also derived ages based on optical photometry from Gaia DR3 and compared the projected spatial distribution to diffuse infrared emission.

We identified 29 TTs, including six new members of the association and three classical TTs. The equivalent width of the LiI absorption line suggests an age of 8.1^+2.1^_-3.8_Myr, while optical photometric data indicate stellar ages ranging from ~1 to 14Myr. Younger stars are concentrated around Sh 2-295, whereas the older ones are more widely dispersed.

We increased the number of known TTs related to the CMa association. Our results support a scenario of multiple star formation episodes, including a younger group that may have been triggered by the expansion of Sh 2-295. The influence of SN events appears limited in this context.