New constraints on the free-streaming of warm dark matter from intermediate and small scale Lyman-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>α</mml:mi></mml:math> forest data

Using data on the Lyman-\ensuremath{\alpha} spectra obtained by the X-shooter and HIRES/MIKE spectrographs, bounds on warm dark matter are computed using state-of-the-art analysis. This places a new best lower limit of 5.3 keV on the mass of thermal relic dark matter.