Baryon Acoustic Oscillations from Integrated Neutral Gas Observations:
  an instrument to observe the 21cm hydrogen line in the redshift range 0.13
  $<$ z $<$ 0.45 -- status update
  BINGO (BAO from Integrated Neutral Gas Observations) is a unique radio
telescope designed to map the intensity of neutral hydrogen distribution at
cosmological distances, making the first detection of Baryon Acoustic
Oscillations (BAO) in the frequency band 980 MHz - 1260 MHz, corresponding to a
redshift range $0.127 < z < 0.449$. BAO is one of the most powerful probes of
cosmological parameters and BINGO was designed to detect the BAO signal to a
level that makes it possible to put new constraints on the equation of state of
dark energy. The telescope will be built in Para\'iba, Brazil and consists of
two $\thicksim$ 40m mirrors, a feedhorn array of 28 horns, and no moving parts,
working as a drift-scan instrument. It will cover a $15^{\circ}$ declination
strip centered at $\sim \delta=-15^{\circ}$, mapping $\sim 5400$ square degrees
in the sky. The BINGO consortium is led by University of S\~ao Paulo with
co-leadership at National Institute for Space Research and Campina Grande
Federal University (Brazil). Telescope subsystems have already been fabricated
and tested, and the dish and structure fabrication are expected to start in
late 2020, as well as the road and terrain preparation.
