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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 (and also joint modelling with Astrometry), 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.

Why EMPEROR?

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

Quick Install

Dependencies

This code makes use of:

All of them can be easily installed with pip.

For additional capabilities, you can install:

Pip

In the console type 

pip install astroemperor

From Source

In the console type 

git clone https://github.com/ReddTea/astroemperor/
cd astroemperor
python -m pip install -e .

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.

📂working_directory
 ┣ 📜mini_test.py
 ┣ 📂datafiles
 ┃ ┣ 📂51Peg
 ┃ ┃ ┗ 📂RV
 ┃ ┃ ┃ ┗ 📜51peg.vels
 ┣ 📂datalogs
 ┃ ┣ 📂51Peg
 ┃ ┃ ┗ 📂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

User Guide

In depth utilities of EMPEROR.

License and Attribution

Copyright (c) 2024 Pablo Peña Rojas.

EMPEROR is open software under the MIT License (see License).

If you use EMPEROR, please cite the paper (arXiv, ADS, SciX, aanda).

BibTeX: 

@ARTICLE{2025A&A...704A.323P,
       author = {{Pe{\~n}a R.}, Pablo A. and {Jenkins}, James S.},
        title = "{EMPEROR: I. Exoplanet MCMC parallel tempering for RV orbit retrieval}",
      journal = {A\&A},
     keywords = {methods: data analysis, methods: numerical, techniques: radial velocities, planets and satellites: detection, planets and satellites: individual: HD 55693, planets and satellites: individual: Barnard's Star, Earth and Planetary Astrophysics, Instrumentation and Methods for Astrophysics},
         year = 2025,
        month = dec,
       volume = {704},
          eid = {A323},
        pages = {A323},
          doi = {10.1051/0004-6361/202554336},
archivePrefix = {arXiv},
       eprint = {2511.05331},
 primaryClass = {astro-ph.EP},
       adsurl = {https://ui.adsabs.harvard.edu/abs/2025A&A...704A.323P},
      adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}