We present new radio , optical , and X-ray observations of three Ultraluminous X-ray sources ( ULXs ) that are associated with large-scale nebulae .
We report the discovery of a radio nebula associated with the ULX IC342 X-1 using the Very Large Array ( VLA ) .
Complementary VLA observations of the nebula around Holmberg II X-1 , and high-frequency Australia Telescope Compact Array ( ATCA ) and Very Large Telescope ( VLT ) spectroscopic observations of NGC5408 X-1 are also presented .
We study the morphology , ionization processes , and the energetics of the optical/radio nebulae of IC342 X-1 , Holmberg II X-1 and NGC5408 X-1 .
The energetics of the optical nebula of IC342 X-1 is discussed in the framework of standard bubble theory .
The total energy content of the optical nebula is 6 \times 10 ^ { 52 } erg .
The minimum energy needed to supply the associated radio nebula is 9.2 \times 10 ^ { 50 } Â erg .
In addition , we detected an unresolved radio source at the location of IC342 X-1 at VLA scales .
However , our Very Long Baseline Interferometry ( VLBI ) observations using the European VLBI Network likely rule out the presence of any compact radio source at milli-arcsecond ( mas ) scales .
Using a simultaneous Swift X-ray Telescope measurement , we estimate an upper limit on the mass of the black hole in IC342 X-1 using the ” fundamental plane ” of accreting black holes and obtain M _ { BH } \leq ( 1.0 \pm 0.3 ) \times 10 ^ { 3 } Â M _ { \odot } .
Arguing that the nebula of IC342 X-1 is possibly inflated by a jet , we estimate accretion rates and efficiencies for the jet of IC342 X-1 and compare with sources like S26 , SS433 , IC10 X-1 .