084055

We propose a 130 ks observation of the MUSE Ultra Deep Field openParMUDFclosePar which comma upon completion comma will be the deepest openParup to 300hclosePar spectroscopic survey ever done with MUSE-VLT. MUDF is centered on a unique field openParP2139-443closePar of two bright comma physically associated quasars at zvirgul3.23 comma separated by virgul500 kpc in projection. Both quasars are embedded within large Ly nebulae openParvirgul100 kpcclosePar comma which are suggestive of an extended filament connecting the two halos of the quasars. Our main aim is to collect high-quality X-ray spectra to characterise the physical properties openPare.g. X-ray slope comma luminosities comma gas column densities comma accretion rateclosePar in the innermost region of this pair with physically associated extended Ly nebulae.