Two new high-precision measurements of the deuterium abundance from absorbers along the line of sight to the quasar PKS1937–1009 were presented .
The absorbers have lower neutral hydrogen column densities ( N ( HI ) \approx 18 cm ^ { -2 } ) than for previous high-precision measurements , boding well for further extensions of the sample due to the plenitude of low column density absorbers .
The total high-precision sample now consists of 12 measurements with a weighted average deuterium abundance of D/H = 2.55 \pm 0.02 \times 10 ^ { -5 } .
The sample does not favour a dipole similar to the one detected for the fine structure constant .
The increased precision also calls for improved nucleosynthesis predictions .
For that purpose we have updated the public AlterBBN code including new reactions , updated nuclear reaction rates , and the possibility of adding new physics such as dark matter .
The standard Big Bang Nucleosynthesis prediction of D/H = 2.456 \pm 0.057 \times 10 ^ { -5 } is consistent with the observed value within 1.7 standard deviations .