ORIGAMI Update - version 1.2

Posted on April 7, 2014

A new version of ORIGAMI, v1.2, is now available; the links to the tarball and documentation, below and on the sidebar, have been updated. ORIGAMI is now released under the Modified BSD license. This update includes some minor bug fixes and the addition of a routine to determine the cosmic web environment of ORIGAMI halos.


Posted on October 12, 2012

The ORIGAMI code consists of a few simple C routines and makes use of the Delaunay tessellation calculation routines from the VOBOZ package, which itself relies on the Qhull package. The most recent ORIGAMI source code tarball is available to download here, and installation instructions are available here. If you would like to use ORIGAMI, have questions, or find issues with the code, please contact me. The code was developed in collaboration with Mark Neyrinck.

Finding Folds in Phase-Space

ORIGAMI is a dynamical method of determining the morphology of particles in a cosmological simulation by checking for whether, and in how many dimensions, a particle has undergone shell-crossing. ORIGAMI appears in the Haloes Gone MAD Comparison Project (see Knebe et al. 2011), and the method paper has been published in ApJ.


The image above shows the Lagrangian (initial) positions of simulation particles colored by their redshift-zero morphology tag, where red = halo, yellow = filament, teal = wall, and blue = void. (Click for a larger image.)