Measure the radial velocity

This notebook uses the RVFitter class to do an MCMC fit. It looks up the spectral type on Simbad to estimate the temperature, and estimates the log(g) from the spectrum (you should have a Balmer line in there somewhere).



In [1]:

    
# Import a bunch of stuff
import StarData
import HelperFunctions
import Fitters
import Mamajek_Table
import SpectralTypeRelations
import matplotlib.pyplot as plt
import logging
import triangle
from astropy.io import fits
import numpy as np
import sys
import os

%matplotlib inline

logger = logging.getLogger()
logger.setLevel(logging.INFO)

# Get the HDF5 filename. Might want to change this eventually.
#home = os.environ['HOME']
#sys.path.append('{}/School/Research/CHIRON_data/Chiron-Scripts/'.format(home))
#from Search_slow import hdf5_filename
hdf5_filename = '/Volumes/DATADRIVE/Kurucz_Grid/TS23_grid_full.hdf5'









    



Module 'anfft' (FFTW Python bindings) could not be imported.
To install it, try running 'easy_install anfft' from the terminal.
Falling back on the slower 'fftpack' module for ND Fourier transforms.






    



:0: FutureWarning: IPython widgets are experimental and may change in the future.



In [2]:

    
flattened_orders = HelperFunctions.ReadExtensionFits('../20130106/HIP_28691_flattened.fits')
%matplotlib notebook
for order in flattened_orders:
    plt.plot(order.x, order.y, 'k-', alpha=0.4)



In [3]:

    
# Fit the RV to the flattened spectrum
teff, logg = 13029.7582664, 3.84273512393
reload(Fitters)
flat_fitter = Fitters.RVFitter(flattened_orders, model_library=hdf5_filename, 
                               T=teff, logg=logg, feh=0.0)
#flat_fitter.fit(backend='multinest', n_live_points=1000, basename='RVFitter/HIP109521_20131021-', overwrite=False)









    



Determine Chunk Log: Wl is 131072



In [4]:

    
flat_fitter.fit(backend='multinest', n_live_points=1000, basename='RVFitter/HIP28691_20130106-', overwrite=False)









    



/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (56347.8469849). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (61459.5413208). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (17263.8893127). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (83904.2663574). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (36103.7254333). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (6828.30810547). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (20129.6806335). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (7467.26989746). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (76258.901258). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (93899.2196423). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (7019.3370191). Not broadening!
  linear=True, findcont=False)
/Users/kgulliks/.PythonModules/GeneralScripts/Fitters.py:1630: UserWarning: vsini too small (8773.93207885). Not broadening!
  linear=True, findcont=False)



In [5]:

    
%matplotlib inline
flat_fitter.triangle()



In [6]:

    
flat_fitter.samples.describe()









    Out[6]:






  
    
      
      RV
      epsilon
      lnprob
      vsini
    
  
  
    
      count
      4802.000000
      4802.000000
      4802.000000
      4802.000000
    
    
      mean
      10.003080
      0.999958
      -4726413.328631
      69.119883
    
    
      std
      0.017158
      0.000043
      1.406978
      0.034871
    
    
      min
      9.946934
      0.999622
      -4726422.565226
      68.998693
    
    
      25%
      9.991472
      0.999942
      -4726414.049124
      69.096499
    
    
      50%
      10.003121
      0.999971
      -4726413.000564
      69.119348
    
    
      75%
      10.014842
      0.999988
      -4726412.284657
      69.143084
    
    
      max
      10.057651
      1.000000
      -4726411.401565
      69.253313



In [7]:

    
%matplotlib notebook
flat_fitter.plot()









    














    











    Out[7]:





<matplotlib.axes._subplots.AxesSubplot at 0x10bfdefd0>



In [ ]:

	RV	epsilon	lnprob	vsini
count	4802.000000	4802.000000	4802.000000	4802.000000
mean	10.003080	0.999958	-4726413.328631	69.119883
std	0.017158	0.000043	1.406978	0.034871
min	9.946934	0.999622	-4726422.565226	68.998693
25%	9.991472	0.999942	-4726414.049124	69.096499
50%	10.003121	0.999971	-4726413.000564	69.119348
75%	10.014842	0.999988	-4726412.284657	69.143084
max	10.057651	1.000000	-4726411.401565	69.253313