{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Example of fitting: 51 Pegasi b\n", "\n", "To show how to fit some RV data, let's start with possibly the most famous exoplanet, 51 Peg b. We will quickly fit a circular model, find a best-fit solution using MAP, explore parameter uncertainty with MAP, and derive a mass-estimate $M_p\\sin{i}$.\n", "\n", "The ELODIE data and parameters used in this example notebook for 51 Peg b were obtained from [Birkby et al. 2017](http://doi.org/10.3847/1538-3881/aa5c87)." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "from pathlib import Path\n", "\n", "import matplotlib.pyplot as plt\n", "import numpy as np\n", "import pandas as pd\n", "from astropy.stats import knuth_bin_width\n", "\n", "import ravest.prior\n", "from ravest.fit import Fitter\n", "from ravest.model import calculate_mpsini\n", "from ravest.param import Parameter, Parameterisation" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [ { "data": { "text/html": [ "
| \n", " | time | \n", "vel | \n", "verr | \n", "tel | \n", "
|---|---|---|---|---|
| 0 | \n", "-7389.467245 | \n", "-33258.0 | \n", "9.0 | \n", "ELODIE | \n", "
| 1 | \n", "-7387.528344 | \n", "-33225.0 | \n", "9.0 | \n", "ELODIE | \n", "
| 2 | \n", "-7344.688737 | \n", "-33272.0 | \n", "7.0 | \n", "ELODIE | \n", "
| 3 | \n", "-7271.772638 | \n", "-33310.0 | \n", "7.0 | \n", "ELODIE | \n", "
| 4 | \n", "-7270.775020 | \n", "-33248.0 | \n", "7.0 | \n", "ELODIE | \n", "
| ... | \n", "... | \n", "... | \n", "... | \n", "... | \n", "
| 148 | \n", "-4387.643306 | \n", "-33266.0 | \n", "8.0 | \n", "ELODIE | \n", "
| 149 | \n", "-4166.392013 | \n", "-33315.0 | \n", "7.0 | \n", "ELODIE | \n", "
| 150 | \n", "-4147.379446 | \n", "-33196.0 | \n", "7.0 | \n", "ELODIE | \n", "
| 151 | \n", "-4141.412989 | \n", "-33300.0 | \n", "8.0 | \n", "ELODIE | \n", "
| 152 | \n", "-4112.460190 | \n", "-33275.0 | \n", "7.0 | \n", "ELODIE | \n", "
153 rows × 4 columns
\n", "| \n", " | P_b | \n", "K_b | \n", "Tc_b | \n", "g_ELODIE | \n", "
|---|---|---|---|---|
| 0 | \n", "4.230002 | \n", "55.976960 | \n", "-674.084961 | \n", "-33250.532144 | \n", "
| 1 | \n", "4.230000 | \n", "56.032717 | \n", "-674.110868 | \n", "-33249.981486 | \n", "
| 2 | \n", "4.229999 | \n", "56.967785 | \n", "-674.121499 | \n", "-33251.031873 | \n", "
| 3 | \n", "4.230001 | \n", "55.040490 | \n", "-674.112143 | \n", "-33251.381550 | \n", "
| 4 | \n", "4.230000 | \n", "55.134806 | \n", "-674.106411 | \n", "-33251.106240 | \n", "
| ... | \n", "... | \n", "... | \n", "... | \n", "... | \n", "
| 11195 | \n", "4.230000 | \n", "56.958168 | \n", "-674.115266 | \n", "-33251.053848 | \n", "
| 11196 | \n", "4.230000 | \n", "54.325356 | \n", "-674.112199 | \n", "-33250.795378 | \n", "
| 11197 | \n", "4.230001 | \n", "56.729050 | \n", "-674.124347 | \n", "-33250.233786 | \n", "
| 11198 | \n", "4.230000 | \n", "57.262604 | \n", "-674.108625 | \n", "-33251.374769 | \n", "
| 11199 | \n", "4.230001 | \n", "55.987968 | \n", "-674.111669 | \n", "-33250.617294 | \n", "
11200 rows × 4 columns
\n", "