njcuk9999/apero_demo

Demonstration exercises to get familiar with the APERO drs

APERO Demos

The aim of these demos is to walk you through some of the key steps in the data reduction using APERO.

• Slides
• Example solutions

Prerequisites for exercises

• Python 3.9 (e.g. via conda)

  conda create --name=apero-demo python=3.9
  conda activate apero-demo
  pip install -r requirements.txt
  

• DS9 (download)

• dfits and fitsort

  • python implementation: download
  • C implmentation: download

• Download the file bundle: download

Exercise 1: Cube to RAMP: Correlated double sampling (CDS)

• Step 1: Find the ramp and the cube for Proxima (HE) HIERARCH ESO DPR TYPE = OBJECT,SKY using dfits and fitsort (or python)
• Step 2: Load the cube in ds9
• Step 3: In DS9 play with the cube scaling (linear, log, histogram, min max, zscale etc)
• Step 4: In DS9 “Animate” the cube to see photons accumulating
• Step 5: In python create CDS “last minus first frame” from the cube. Express the resulting image in ADU/s
• Step 6: In DS9 compare to provided ramp image for Proxima

Example answer code: demo1.py

Exercise 2: Looking at detector cosmetics

• Step 1: Find the DARK_FP RAMP file
• Step 2: In python remove horizontal striping
• Step 3: In python remove the “butterfly” pattern

Example answer code: demo2.py

Exercise 3: Calibrating a 2D image

• Step 1: Find the localization files (A and B)
• Step 2: Find the wavelength solution file
• Step 3: Find the preprocessed Proxima image
• Step 4: In python overplot the localization traces on the preprocessed image
• Step 5: In python add the wavelengths at 10 nm intervals to the step 4 plot (i.e. at …, 1200nm, 1210nm, 1220nm, 1230nm, …)

Example answer code: demo3.py

Exercise 4: Extraction, making the S1D

• Step 1: Find the e2dsff A file for Proxima
• Step 2: Find the associated blaze file using the e2dsff header
• Step 3: Get the wavelength solution from the e2dsff (header or ORDER_TABLE extension)
• Step 4: In python construct a 1D wavelength grid
• Step 5: In python calculate an S1D using the blaze and the flux

Example answer code: demo4.py

Exercise 5: Telluric correction

• Step 1: Find the extracted s1d for Proxima (fiber A)
• Step 2: Find the telluric corrected s1d for Proxima (fiber A)
• Step 3: Find the associated recon and s1d template
• Step 4: Shift the s1d template using the BERV
• Step 5: Plot the flux (corrected/uncorrected) and template
• Step 6: Plot the normalized ratio of the corrected flux to template
• Step 7: Plot the transmission
• Bonus: Plot the OH line model from the pclean file (use fitsinfo to look at the extension names)

Example answer code: demo5.py

Exercise 6: Radial velocities using the line-by-line approach

• Step 1: Get the tcorr LBL file for Proxima
• Step 2: Get the associated recon file for the tcorr Proxima file.
• Step 3: Plot a histogram of the sigma away from the mean velocity
• Step 4: Plot the “trumpet plot” with the 3.5 sigma outliers and see if they match absorption features.

Example answer code: demo6.py