We present the clustering properties of 151 Lyman- \alpha emitting galaxies at z \approx 4.5 selected from the Large Area Lyman Alpha ( LALA ) survey .
Our catalog covers an area of 36 ’ x 36 ’ observed with five narrowband filters .
We assume that the angular correlation function w ( \theta ) is well represented by a power law A _ { w } \Theta ^ { - \beta } with slope \beta = 0.8 , and we find A _ { w } = 6.73 \pm 1.80 .
We then calculate the correlation length r _ { 0 } of the real-space two-point correlation function \xi ( r ) = ( r / r _ { 0 } ) ^ { -1.8 } from A _ { w } through the Limber transformation , assuming a flat , \Lambda -dominated universe .
Neglecting contamination , we find r _ { 0 } = 3.20 \pm 0.42 h ^ { -1 } Mpc .
Taking into account a possible 28 % contamination by randomly distributed sources , we find r _ { 0 } = 4.61 \pm 0.6 h ^ { -1 } Mpc .
We compare these results with the expectations for the clustering of dark matter halos at this redshift in a Cold Dark Matter model , and find that the measured clustering strength can be reproduced if these objects reside in halos with a minimum mass of 1– 2 \times 10 ^ { 11 } h ^ { -1 } M _ { \odot } .
Our estimated correlation length implies a bias of b \sim 3.7 , similar to that of Lyman-break galaxies ( LBG ) at z \sim 3.8 - 4.9 .
However , Lyman- \alpha emitters are a factor of \sim 2 –16 rarer than LBGs with a similar bias value and implied host halo mass .
Therefore , one plausible scenario seems to be that Lyman- \alpha emitters occupy host halos of roughly the same mass as LBGs , but shine with a relatively low duty cycle of 6–50 % .