Stage 20

This step finally extracts the spectra!

A new directory will be created in the work directory. It will look similar to this workdir + extracted_lc/2022-01-21_18-33-25. We will save the flux information there.

PACMAN uses optimal extraction to extract the spectra.

This effectively converts these 2D spectra:

_images/sp2d_0.png

Into 1D spectra:

_images/sp1d_0.png

The way PACMAN determines the rows which should be used in optimal extraction can be seen in the following plot:

_images/utr0-11.png

The first panel (left) shows the 2D spectrum. The column limits are determined using the trace.

The second panel (middle) shows the median flux in every column.

The third panel (right) shows the absolute difference between the median flux in the adjacent columns. We use these two rows where the flux changes the most as reference rows. The pcf file contains a window parameter. If the two determined peaks are at row=155 & row = 162 and window was set to 12, the data between rows 155-12 and 162+12 will be used in the optimal extraction.

When running Stage 20 you will see an output similar to the following:

Successfully reloaded meta file
Starting s20
in total #visits, #orbits: (3, 12)

***************** Looping over files:   0%|          | 0/225 [00:00<?, ?it/s]
Filename: /home/zieba/Desktop/Data/GJ1214_Hubble13021/ibxy07paq_ima.fits
current visit, orbit:  (0, 0)
--- Looping over up-the-ramp-samples: 100%|██████████| 14/14 [00:00<00:00, 28.74it/s]


***************** Looping over files:   0%|          | 1/225 [00:00<02:53,  1.29it/s]
Filename: /home/zieba/Desktop/Data/GJ1214_Hubble13021/ibxy07pbq_ima.fits
current visit, orbit:  (0, 0)
--- Looping over up-the-ramp-samples: 100%|██████████| 14/14 [00:00<00:00, 21.12it/s]


***************** Looping over files:   1%|          | 2/225 [00:01<03:05,  1.20it/s]
Filename: /home/zieba/Desktop/Data/GJ1214_Hubble13021/ibxy07pcq_ima.fits
current visit, orbit:  (0, 0)
--- Looping over up-the-ramp-samples: 100%|██████████| 14/14 [00:00<00:00, 21.96it/s]




***************** Looping over files: 100%|█████████▉| 224/225 [03:43<00:00,  1.05it/s]
Filename: /home/zieba/Desktop/Data/GJ1214_Hubble13021/ibxy10pmq_ima.fits
current visit, orbit:  (2, 11)
--- Looping over up-the-ramp-samples: 100%|██████████| 14/14 [00:00<00:00, 25.90it/s]


***************** Looping over files: 100%|██████████| 225/225 [03:44<00:00,  1.00it/s]
Saving Metadata
Finished s20

After Stage 20 we can either:

  • Continue with Stage 21 if the user wants to fit spectroscopic light curves.

  • Continue with Stage 30 to fit the broadband (“white”) light curve.