Author: Martin Kilbinger

athena: Tree code for second-order correlation functions

Martin Kilbinger, CEA Saclay, Service d'Astrophysique (SAp), France

METHOD athena is a 2d-tree code written in C, which estimates second-order correlation functions from input galaxy catalogues. These include shear-shear correlations (cosmic shear), position-shear (galaxy-galaxy lensing) and position-position (spatial angular correlation).

  DOWNLOAD Get the latest version athena_1.7.tgz. A readme file is available. Run the code on the test data set. New features and bug fixes in version 1.7 (Mar 2014):

• General
  • Added FITS file support. Input catalogues and output correlation function files can be both in ascii or fits format.
    (Note: If reading a FITS file causes a segmentation fault, remove the compiler option "-std=c99", either from CMakeLists.txt or src/Makefile.athena".)
  • Format of resample files changed, only relevant columns are output.
  • Compilation of code automated using cmake. Alternatively, the traditional Makefile is still usable.
  • Directory structure changed.

To compile and run the code, you need a C-compiler. To calculate the angular correlation function, including reading mask files and creating random catalogues, gsl and perl and required. The library cfitsio is optional (for FITS file support).

Further scripts are part of the athena package:

• The python script pallas.py calculates (band-)power spectrum by integrating over the correlation function using an estimator from this paper. Further, the aperture-mass dispersion is compuated, also via integrating the correlation function.
• The perl script woftheta_xcorr.pl is the master script for angular correlation function calculations. It creates random catalogues and calls athena for all necessary combinations of data and random catalogues, including redshift bins, and outputs the Landy & Szalay (1993) and Hamilton (1993) estimators of the correlation function.
• Two perl scripts (cat2gal.pl and center_gal.pl) calculate projections of an input catalogue in spherical coordinates, and transform an arbitrary (ascii) input catalogue into an athena-readable format.
• The python script test_suite_athena.py runs a series of tests for easy comparison with expected results.
• Various scripts to transform and plot resampled data (e.g. Jackknife)

• ---

  For older versions of athena please contact me (martin.kilbinger at cea.fr).

REFERENCES

• athena on the Astrophysics Source Code Library: ascl link, ads link.
• pallas: Schneider, van Waerbeke, Kilbinger & Mellier, 2002, A&A, 396, 1

AUTHORS
Martin Kilbinger
Christopher Bonnett (gal-gal lensing)
Jean Coupon (venice)

With helpful suggestions from Henry McCracken, Lance Miller, and Barnaby Rowe. Ami Choi, Jonathan Benjamin, Matthieu Béthermin, and Shahab Joudaki are thanked for testing the code and bug-hunting.

CONTACT
Please feel free to send questions, feedback and bug reports to martin.kilbinger@cea.fr. If you want to be added to the athena mailing list, to get updates about new versions and bug-fixes, send me a mail to martin.kilbinger@cea.fr. 

LINKS
CosmoPMC (cosmology sampling with Population Monte Carlo [PMC])
nicaea (cosmology and lensing package)
reduced-shear corrections home

Last updated February 2017.

Counts of Amplified Mass Elevations from Lensing with Ultrafast Simulations
Chieh-An Lin (University of Edinburgh)

Description

Camelus is a fast weak lensing peak count modeling in C. It provides a prediction on peak counts from input cosmological parameters.

Here is the summary of the algorithm:

• Sample halos from a mass function
• Assign density profiles, randomize their positions
• Compute the projected mass, add noise
• Make maps and create peak catalogues

For a more detailed description, please take a look at Lin & Kilbinger (2015a).

Downloads

Please check the GitHub page of Camelus.

Requirements

The following softwares are required:

• cmake
• gcc
• gsl
• fftw
• nicaea v2.5

Updates

Current release: Camelus v1.31

New features in v1.31 - Mar 22, 2016:

• Made installation more friendly by removing the dependency on cfitsio and mpi
• Added the routine for computing 1-halo & 2-halo terms of the convergence profile
• Flexible parameter space for PMC ABC
• Remove files: FITSFunctions.c/.h

New features in v1.3 - Dec 09, 2015:

• New files: constraint.c/.h
• Allowed multiscale peaks in one data vector
• Allowed a data matrix from several realizations
• Used the local galaxy density as the noise level in the S/N
• Increased the parameter dimension for PMC ABC
• Changed the summary statistic options for PMC ABC

New features in v1.2 - Apr 06, 2015:

• Improved the computation speed by a factor of 6~7
• Converted the halo array structure into a binned structure, called "halo_map"
• Converted the galaxy tree structure into a binned structure, called "gal_map"
• Added the population Monte Carlo approximate Monte Carlo (PMC ABC) algorithm

New features in v1.1 - Jan 19, 2015:

• Fixed the bug from calculating halo radii

New features in v1.0 - Oct 24, 2014:

• Fast weak lensing peak count modeling

References

• Bartelmann & Schneider (2001). Phys. Rep., 340, 291.
• Fan et al. (2010). ApJ, 719, 1408.
• Lin & Kilbinger (2017), submitted to A&A.
• Lin, Kilbinger & Pires (2016), A&A, 593, A88.
• Lin & Kilbinger (2015a). A&A, 576, A24.
• Lin & Kilbinger (2015b), 583, A70.
• Lin & Kilbinger (2015c), ascl:1502.015 (software page)
• Peel, Lin et al. (2017), 599, A79.
• Marin et al. (2011).
• Takada & Jain (2003a). MNRAS, 340, 580.
• Weyant et al. (2013). ApJ, 764, 116.

Contact information

Authors:

• Chieh-An Lin
• Martin Kilbinger
• François Lanusse

Please feel free to send questions, feedback and bug reports to calin AT roe DOT ac DOT uk.

Last updated Jun 26, 2015.