EXOMOP

EXOplanet Modeling Package v5.0

Created by Jake Turner

Questions, comments, or concerns can be addressed to

turner(at)email(dot)arizona(dot)edu

To download from terminal type:

wget http://uaastroclub.org/wp-content/uploads/2013/02/EXOMOPv5.0.zip

WHAT IT DOES:

– Finds a linear or quadratic fit to your out of transit baseline. Then it divides your transit by this fit to get a de-trended light curve.

– Fits your de-trended transit data using Levenberg-Marquardt least-squares techniques to a Mandel & Agol (2002) model

– Finds robust errors using the Bootstrap Monte Carlo technique

-Fits your de-trended transit data using a Differential Evolution Markov Chain Monte Carlo (MCMC) fit (ter Braak, 2006) and finds errors.
– Program stops when chains are well-defined using the Gelman-Rubin Statistic (Ford 2006)

– Finds the asymmetry of the transit about the calculated mid-transit time

– Uses the Prayer Bead Method (Residual-Permutation Method) to access the influence of red noise on the transit and calculates new errors (two different methods)

– Uses the Time-Averaging Method (Beta Method) to further access the influence of red noise.

TO COMPILE:

Simply put these procedures in your IDL path

INPUT REQUIREMENTS:

– Your transit file. This file needs to contain: Time (HJD), Normalized Flux, Error

(Program will not run unless you have error bars for each data point)

TO RUN:

In an IDL command window, navigate to the directory containing

your transit file. Then, type:

.r Useful_Values.pro

.r Detrend_linfit.pro

.r Detrend_quadfit.pro

.r exomop_prayer.pro

.r exomop_mcmc.pro

.r EXOMOPv5.0.pro

ENSURING YOU HAVE RELIABLE ERROR BARS:

– Check to make sure that the gauss.ps and gauss_prayer.ps plots are gaussian. If they are not, run your model with more/less fixed parameters

– Also, pay attention to the Bayesian information criterion value (lower values are usually better).

– The file FINAL_EVERYTHING.dat includes all parameter fits, respective errors, both red noise calculation results and residuals.

– It is recommend that you choose the method (LM or MCMC) that minimized the residuals

– Multiple your error bars from FINAL_EVERYTHING.dat for each parameter by the largest beta (either the global value or individual parameter betas)

– To get your final error bars multiple the error bars from step 3 by sqrt(Chi-Squared), where Chi-Squared is the Reduced Chi-Squared in
FINAL_EVERYTHING.dat file. Only do this if the Reduced Chi-Squared is greater than one.

LIMITATIONS:

– Does not fit for period

* These programs (EXOMOPv5.0.pro,model_fit.pro,Useful_Values.pro, Detrend_linfit.pro, beta.pro, bin.pro, beta_model.pro,exomop_mcmc.pro,exomop_chi2.pro,exomop_prayer.pro) are free

* software; you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation; either version 3 of the License, or

* (at your option) any later version.

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

* You should have received a copy of the GNU General Public License

* along with this program; if not, see <http://www.gnu.org/licenses/>