A soft and transient ultraluminous X-ray source with 6-h modulation in the NGC 300 galaxy

A. Sacchi, P. Esposito, D. de Martino +13

We investigate the nature of CXOU J005440.5-374320 (J0054), a peculiar bright ($\sim$$4\times 10^{39}$ erg/s) and soft X-ray transient in the spiral galaxy NGC 300 with a 6-hour per…