Bolshoi Catalogs Public Release, version 1.55.  (12/18/2015).

Each "hlist" file is a catalog which contains all the halos and subhalos at a
single simulation output, in ASCII format.

The numbers in the filename (e.g., hlist_0.XYZ) refer to the scale factor of the
output.  Each halo record is a single line, which has many space-separated columns.
The details of what is in each column is contained in the first few lines of each
catalog, and includes halo positions, velocities, masses, and many other useful
properties.  Some columns contain indices (e.g., depthFirstIndex) which are only
relevant for merger trees---these are kept only for consistency with the merger
tree format.

Note: Previous issues concerning T/|U|, the Peebles spin parameter, and	the
next_coprogenitor_depthfirst_id have been corrected in these catalogs.
Versions >= 1.53 also correct an issue affecting the MMP flag and include a new field
(last_mainleaf_depthfirst_ID) to help with extracting main progenitor histories.

If you use these catalogs, please cite the following four papers:

The original Bolshoi-Planck simulation paper: http://arxiv.org/abs/1411.4001 (Klypin et al. 2014).
The Rockstar halo finder paper: http://arxiv.org/abs/1110.4372 (Behroozi, Wechsler, and Wu, 2012).
The consistent merger trees paper: http://arxiv.org/abs/1110.4370 (Behroozi et al. 2012).
The paper describing these catalogs: http://arxiv.org/abs/1602.04813 (Rodriguez-Puebla et al. 2016).