2019MNRAS.484L..24S

We have found three new luminous blue variable (LBV) candidates in the star-forming galaxy NGC 4736. They show typical well-known LBV spectra, broad and strong hydrogen lines, He I lines, many Fe II lines, and forbidden [Fe II] and [Fe III]. Using archival Hubble Space Telescope and ground-based telescope data, we have estimated the bolometric magnitudes of these objects from -8.4 to -11.5, temperatures, and reddening. Source NGC 4736_1 (M_v = -10.2 ± 0.1 mag) demonstrated variability between 2005 and 2018 as ΔV ≃ 1.1 mag and ΔB ≃ 0.82 mag; the object belongs to LBV stars. NGC 4736_2 (M_v < -8.6 mag) shows P Cyg profiles and its spectrum has changed from 2015 to 2018. The brightness variability of NGC 4736_2 is ΔV ≃ 0.5 mag and ΔB ≃ 0.4 mag. In NGC 4736_3 (M_v = -8.2 ± 0.2 mag), we found strong nebular lines, broad wings of hydrogen; the brightness variation is only ≃0.2 mag. Therefore, the last two objects may reside to LBV candidates.