Context :

Aims : We wish to investigate the structure , velocity field , and stellar content of the G16.59 - 0.05 high-mass star-forming region , where previous studies have established the presence of two almost perpendicular ( NE–SW and SE–NW ) , massive outflows , and a rotating disk traced by methanol maser emission .

Methods : We performed Very Large Array observations of the radio continuum and ammonia line emission , complemented by COMICS/Subaru and Hi-GAL/Herschel images in the mid- and far-infrared ( IR ) .

Results : Our centimeter continuum maps reveal a collimated radio jet that is oriented E–W and centered on the methanol maser disk , placed at the SE border of a compact molecular core .
The spectral index of the jet is negative , indicating non-thermal emission over most of the jet , except the peak close to the maser disk , where thermal free-free emission is observed .
We find that the ammonia emission presents a bipolar structure consistent ( on a smaller scale ) in direction and velocity with that of the NE–SW bipolar outflow detected in previous CO observations .
After analyzing our previous N _ { 2 } H ^ { + } ( 1–0 ) observations again , we conclude that two scenarios are possible .
In one case both the radio jet and the ammonia emission would trace the root of the large-scale CO bipolar outflow .
The different orientation of the jet and the ammonia flow could be explained by precession and/or a non-isotropic density distribution around the star .
In the other case , the N _ { 2 } H ^ { + } ( 1–0 ) and ammonia bipolarity is interpreted as two overlapping clumps moving with different velocities along the line of sight .
The ammonia gas also seems to undergo rotation consistent with the maser disk .
Our IR images complemented by archival data allow us to derive a bolometric luminosity of \sim 10 ^ { 4 } ~ { } L _ { \odot } and to conclude that most of the luminosity is due to the young stellar object in the hot molecular core .

Conclusions : The new data suggest a scenario where the luminosity and the outflow activity of the whole region could be dominated by two massive young stellar objects : 1 ) a B-type star of \sim 12 M _ { \odot } at the center of the maser/ammonia disk ; 2 ) a massive young stellar object ( so far undetected ) , very likely in an earlier stage of evolution than the B-type star , which might be embedded inside the compact molecular core and power the massive , SE–NW outflow .