We present the largest-ever sample of 79 Ly \alpha emitters ( LAEs ) at z \sim 7.0 selected in the COSMOS and CDFS fields of the LAGER project ( the Lyman Alpha Galaxies in the Epoch of Reionization ) .
Our newly amassed ultradeep narrowband exposure and deeper/wider broadband images have more than doubled the number of LAEs in COSMOS , and we have selected 30 LAEs in the second field CDFS .
We detect two large-scale LAE-overdense regions in the COSMOS that are likely protoclusters at the highest redshift to date .
We perform injection and recovery simulations to derive the sample incompleteness .
We show significant incompleteness comes from blending with foreground sources , which however has not been corrected in LAE luminosity functions in the literature .
The bright end bump in the Ly \alpha luminosity function in COSMOS is confirmed with 6 ( 2 newly selected ) luminous LAEs ( L _ { Ly \alpha } > 10 ^ { 43.3 } erg s ^ { -1 } ) .
Interestingly , the bump is absent in CDFS , in which only one luminous LAE is detected .
Meanwhile , the faint end luminosity functions from the two fields well agree with each other .
The 6 luminous LAEs in COSMOS coincide with 2 LAE-overdense regions , while such regions are not seen in CDFS .
The bright-end luminosity function bump could be attributed to ionized bubbles in a patchy reionization .
It appears associated with cosmic overdensities , thus supports an inside-out reionization topology at z \sim 7.0 , i.e. , the high density peaks were ionized earlier compared to the voids .
An average neutral hydrogen fraction of x _ { HI } \sim 0.2 – 0.4 is derived at z \sim 7.0 based on the cosmic evolution of the Ly \alpha luminosity function .