Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Rahul Biswas Applicant's institution: ANL Applicant's division: HEP Project Name: CosmoInfererences Project title: Estimation of Cosmological Parameters from Large Surveys Associated funding: Other Systems: Science: The science objective of this project will be to develop codes to estimate cosmological parameters from simulations of future cosmological surveys. Constraining cosmological parameters from multiple probes simultaneously is the best way of improving our knowledge about dark energy, the cause of the late time acceleration of the universe. The focus of interest will be the supernova component of the Dark Energy Survey, but will also be working on the same problem for the Large Synoptic Survey Telescope. The project will explore different methods of performing the parameter estimation, taking into account systematics of these surveys to determine which methods afford the best recovery of information within a practical time scales. A code that prove well suited to the task, might ultimately be used for analyzing the data from these surveys. Project description: This project will largely employ Markov Chain Monte Carlo methods to sample multi-dimensional Bayesian Posterior Distributions given simulated data. While such methods are often used in ideal situations, we will need to perform these estimates accounting for experimental systematics, such as those studied by us in simulating the Dark Energy Survey (DES) Supernova (SN) survey. The goal would be to produce a code that can be added as a module to the DES analysis pipeline or used separately for the SN component of the DES. Standard publicly available open-source packages such as (cosmoMC http://cosmologist.info/cosmomc/) exist for a treatment of the problem in ideal situations and simpler models. These codes are written in Fortran90 and use a hybrid parallelization involving both MPI and OpenMP. The general concept is that model evaluations are performed using OpenMP, while several MCMC chains are simultaneously evolved using MPI in an embarrassingly parallel mode. We plan to use small numbers of nodes ~ 10 per job. We have modified these packages to allow for some of the models we need, and used them on fusion (work done on startup/ cosmology projects). We need to develop code to extend the parametrization to include parameters that would encode the experimental details. We have studied such details in a previous DES simulation study and estimated the size of constraints based on linearity. The project will require a LAPACK installation (as installed) and some analysis tools are already in MATLAB (also installed). I expect to mostly work by myself on this project, but would like to invite people working on related topics to collaborate. Accordingly, I think 5 project members would be useful to have. We might run some non-parallel jobs for the purpose of debugging and analysis stage. I expect this to be a small fraction of the time eg. less than 5 percent. Project URL: Requested allocation: 20000 Q1: 5000 Q2: 5000 Q3: 5000 Q4: 5000 Justification: The requester has used undetermined amount hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System