1970011

GX 339-4 is the archetype of low-mass X-ray binary/microquasar. It recently entered into a new X-ray outburst (ATels 15577 15578) and was also detected at other wavelengths (radio ATels 1580). The source is currently in a standard hard X-ray state associated with the presence of a strong collimated compact jet. It is a one of the very few microquasar where multi-wavelength sub-second variability has been detected (ie including infra red observations). As such a multi-wavelength campaign including MeerKat Visir at ESO and the recently launched JWST is currently ongoing (eg ATel 15596). We want to take the opportunity of the next JWST observation scheduled on Sept. 10 @ 00h42 UTC lasting about 3 hours to obtain simultaneous coverage at high-energies with INTEGRAL. This will permit us to probe the > 20 keV spectral region and in particular search for signatures of the said jet. Additionally the fast time variability of the source can be searched with non-standard techniques especially in the range 20-100 keV. While JEM-X will provide a soft X-ray spectrum the core of the justification is based on IBIS (SPI being in annealing during rev 2547 when the JWST observations is meant to occur). [truncated! Please see actual data for full text]