SIMBAD references

We report on the first detection of maser emission in the J=11-10, J=14-13, and J=15-14 transitions of the v=0 vibrational state of SiS toward the carbon-rich star IRC +10216. These masers seem to be produced in the very inhomogeneous region between the star and the inner dust formation zone, located at ≃(5-7)R_*, with expansion velocities below 10 km.s^–1. We interpret the pumping mechanism as being due to overlaps between v=1-0 rovibrational lines of SiS and mid-IR lines of C₂H₂, HCN, and their ¹³C isotopologues. The large number of overlaps found suggest the existence of strong masers for high-J v=0 and v=1 SiS transitions, located in the submillimeter range. In addition, it could be possible to find several rotational lines of the SiS isotopologues displaying maser emission.