Clustering of the Lyman Alpha Clouds in the Line of Sight to the Z=3.66 QSO 0055-269

Cristiani, S.; D'Odorico, S.; Fontana, A.; Giallongo, E.; Savaglio, S.

Clustering of the Lyman Alpha Clouds in the Line of Sight to the Z=3.66 QSO 0055-269

Authors

Description

The spectrum of the Q0055-269 ($z=3.66$) has been observed at the resolution of 14 km s$^{-1}$ in the wavelength interval 4750--6300 Å. The statistical distribution of the Doppler parameter for the Ly$_α$ lines is peaked at $b\simeq 23$ km s$^{-1}$. The column density distribution is described by a power-law with a break at $\log N_{HI} \simeq 14.5$. Significant clustering, with $ξ\simeq 1$ at $Δv=100$ km s$^{-1}$, is detected for lines with $\log N_{HI} \geq 13.8$. Two voids of size $\sim 2000$ km s$^{-1}$ are found in the spectrum with a probability of $2\times 10^{-4}$.
4 pages uuencoded compressed postscript, to appear in the proceedings of the ESO Workshop on "QSO Absorption Lines", Garching 21-24 November 1994