NIRDust: Near Infrared Dust Finder

NIRDust is a python package that uses K-band (2.2 micrometers) spectra to measure the temperature of the dust heated by an Active Galactic Nuclei (AGN) accretion disk.

Motivation:

K-band nuclear/circumnuclear spectral continuum of Type 2 AGNs is often composed of two components: the stellar population emission and a hot 700 - 1600 K dust component. If a Reference Spectrum is used to model the stellar emission, the dust component can be fitted by a blackbody function in order to obtain its temperature.

Features

The package provides several functionalities to pre-process spectra and fit the hot dust component of a AGN K-band spectrum with black body functions.

NIRDust needs a minimum of two spectra to run: a target one, where the dust temperature will be determined, and a reference spectrum, where the emission is considered to be purely stellar. The reference spectrum spectrum will be used by NIRDust to model the stellar emission from the target spectrum.

Footnote: the hot dust component may or may not be present in your type 2 nuclei, do not get disappointed if NIRDust finds nothing.

Requeriments

You will need Python 3.8 or higher to run NIRDust.

Installation

You can install the least stable version of NIRDust from pip:

$ pip install nirdust

Or, for the develovepment instalation clone this repository and then inside the local directory execute

$ pip install -e .

Citation

If you use NIRDust in a scientific publication, we would appreciate citations to the following paper:

Gaspar, Gaia and Chalela, Martín and Cabral, Juan and Alacoria, José and Mast, Damián and Díaz, Rubén J (2024). NIRDust: probing hot dust emission around type 2 AGN using K-band spectra. 10.1093/mnras/stae008

Bibtex

@article{10.1093/mnras/stae008,
    author = {Gaspar, Gaia and Chalela, Martín and Cabral, Juan and Alacoria, José and Mast, Damián and Díaz, Rubén J},
    title = "{nirdust: probing hot dust emission around type 2 AGN using K-band spectra}",
    journal = {Monthly Notices of the Royal Astronomical Society},
    volume = {528},
    number = {2},
    pages = {2952-2963},
    year = {2024},
    month = {01},
    issn = {0035-8711},
    doi = {10.1093/mnras/stae008},
    url = {https://doi.org/10.1093/mnras/stae008},
    eprint = {https://academic.oup.com/mnras/article-pdf/528/2/2952/56541590/stae008.pdf},
}

Full-text: https://arxiv.org/abs/1912.09585