Quickstart

Ensure you have followed the installation instructions before proceeding with this quickstart guide.

If any example below requires data from the Link to Google Drive folder, it will automatically download the necessary files to the local resources directory.

Examples below assume the user has set the environment variable LIGER_IRIS_DRP_RESOURCE_DIR to a valid directory path, or is using the default resources directory.

Throughput

Instrument throughput curves map wavelength (in microns) to fractional throughput for the imager and IFS modes.

Instrument throughputs are sampled at several wavelengths across the bandpass.

These values do not include the filter transmission.

These are directly included with the package:

from liger_iris_drp_resources.throughput import load_throughputs

# Liger imager
waves, tput = load_throughputs("liger", "img")

# Liger IFS (slicer or lenslet)
waves, tput = load_throughputs("liger", "ifs", "slicer")
waves, tput = load_throughputs("liger", "ifs", "lenslet")

# IRIS imager or IFS
waves, tput = load_throughputs("iris", "img")
waves, tput = load_throughputs("iris", "ifs")

Both waves and tput are numpy arrays.

Filters

A summary table of the filters is included with the package.

from liger_iris_drp_resources.filters import load_filters_summary

# Summary table — dict keyed by filter name
filters = load_filters_summary()
print(filters["K"])
# -> {'filter': np.str_('K'), 'wavemin': np.float64(2.0), 'wavecenter': np.float64(2.2), 'wavemax': np.float64(2.4), 'bandwidth': np.float64(0.4), 'backmag': np.float64(15.1028), 'zpphot': np.float64(4564590399.386499), 'transmission_file': np.str_('iris_filter_K.txt')}

Filter transmission curves are downloaded from the Google Drive.

from liger_iris_drp_resources.filters import download_filter_transmission_curves, load_filter_transmission_curve

# Transmission curve for a specific filter
wave, trans = load_filter_transmission_curve("K")

Gratings

A summary table of the IFS gratings is included with the package.

from liger_iris_drp_resources.gratings import load_gratings_summary

gratings = load_gratings_summary()
print(gratings["K4000"])
# -> {'grating': np.str_('K4000'), 'groov_density': np.int64(151), 'resolution': np.int64(4000), 'alpha': np.float64(10.3), 'dimension': np.float64(32.801), 'wavemin': np.float64(1.975), 'wavemax': np.float64(2.412), 'wavecenter': np.float64(2.1825)}

Model Spectra

Model spectra are hosted on Google Drive. The data simulator and pipeline use specific files stored here.

from liger_iris_drp_resources.model_spectra import download_model_spectra

download_model_spectra()
# Files are saved to /path/to/resources/Model_Spectra/

PSFs

Liger PSFs are hosted on Google Drive as a zip archive.

IRIS PSFs are not yet available.

from liger_iris_drp_resources.psfs import load_liger_psf

# Load the PSF closest to 1248 nm at position (0", 0")
psf, info = load_liger_psf(
    instrument_mode='img', # Instrument mode: 'img' or 'ifs'
    wave=1.248, # Wavelength in microns
    xdet=1024, ydet=1024, # Detector coords
)