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EMPEROR

Exoplanet Mcmc Parallel tEmpering for Rv Orbit Retrieval

Overview

EMPEROR (Exoplanet Mcmc Parallel tEmpering for Rv Orbit Retrieval), is a Python-based algorithm that automatically searches for signals in Radial Velocity timeseries, employing Markov chains and parallel tempering methods, convergence tests and Bayesian statistics, along with various noise models. A number of posterior sampling routines are available, focused on efficiently searching for signals in highly multi-modal posteriors. The code allows the analysis of multi-instrument and multi-planet data sets and performs model comparisons automatically to return the optimum model that best describes the data.

Make sure to check the documentation!

Why EMPEROR?

  • It's really simple to use
  • It has a series of configuration commands that will amaze you
  • Advanced Noise Model
  • Quite Flexible!

Dependencies

This code makes use of:

All of them can be easily installed with pip.

For additional capabilities, you can install:

Installation

Pip

In the console type

pip3 install astroEMPEROR

From Source

In the console type

git clone https://github.com/ReddTea/astroEMPEROR.git

Installation Verification

Download the tests folder and run test_basic.py to make sure everything works!

In terminal:

python test_basic.py

Quick Usage

We need to set up our working directory with two subfolders, datafiles and datalogs, the former for data input, the later for output.

๐Ÿ“‚working_directory
 โ”ฃ ๐Ÿ“œmini_test.py
 โ”ฃ ๐Ÿ“‚datafiles
 โ”ƒ โ”ฃ ๐Ÿ“‚51Peg
 โ”ƒ โ”ƒ โ”— ๐Ÿ“‚RV
 โ”ƒ โ”ƒ โ”ƒ โ”— ๐Ÿ“œ51peg.vels
 โ”ฃ ๐Ÿ“‚datalogs
 โ”ƒ โ”ฃ ๐Ÿ“‚51Peg
 โ”ƒ โ”ƒ โ”— ๐Ÿ“‚run_1

Running the code is as simple as:

import astroemperor

sim = astroemperor.Simulation()

sim.set_engine('reddemcee')
sim.engine_config['setup'] = [2, 100, 500, 1]
sim.load_data('51Peg')  # read from ./datafiles/

sim.plot_trace['plot'] = False  # deactivate arviz plots
sim.autorun(1, 1)  # (from=1, to=1): just 1 keplerian

Outputs

All results can be found in the datalogs folder. You will see chain plots, posterior plots, histograms, phasefolded curves, the chain sample and more!