Data analysis pipeline for evaluating flux recovery in millimeter-wave galaxy observations from the Gran Telescopio Milimétrico (GTM), using TolTEC camera simulations.
The pipeline compares simulated input flux against TolTEC's observed output across three wavelength bands (1.1 mm, 1.4 mm, 2.0 mm) to quantify instrument accuracy and derive calibration factors.
All notebooks are located in the TolTEC Galaxy Analysis/ folder.
Introductory guide to working with FITS files using astropy.io.fits. Covers:
- Opening a FITS file and inspecting its structure with
info() - Accessing image data (HDU arrays) and headers
- Displaying 2D images with
matplotlib - Reading binary table extensions (
.srl.FITS) and accessing specific columns and rows
Step-by-step walkthrough of the full flux comparison workflow. Covers:
- Loading a TolTEC observation with
ToltecSignalFitsand applying a weight cut - Reading simulated input sources from a
.csvcatalog withSimuInputSources - Performing PSF photometry with
inphotPSto compare input vs. observed flux - Extracting PyBDSF source catalogs with
BdsfCat - Matching catalogs with
CatalogMatchand plotting results
Minimal worked example using a single source catalog at 1.1 mm. Useful for understanding the photometry workflow before scaling up.
Demonstrates that the input-to-observed flux relationship is not one-to-one and derives a calibration constant:
- Computes the ratio between input and observed flux across all sources
- Applies the mean ratio as a calibration factor
- Plots flux comparisons before and after calibration
Complete analysis pipeline applied to the galaxy NGC 3938 across all three TolTEC bands:
- Segments images with
photutilsto identify sources - Reprojects the input model (MIPS 24 µm resolution) to TolTEC resolution using a Gaussian convolution kernel
- Performs aperture and PSF photometry
- Compares input vs. observed fluxes per band
Python · NumPy · Astropy · Matplotlib · Photutils · Jupyter