NIRDust: Probing Hot Dust Emission around Type 2 AGN using K-band Spectra

GAIA GASPAR; MARTÍN CHALELA; JUAN CABRAL; JOSÉ ALACORIA; DAMIÁN MAST; RUBÉN DÍAZ

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2024

0035-8711

Hot dust in the proximity of AGNs strongly emits in the Near Infrared producing a red excess that, in type 2 sources, can bemodeled to measure its temperature. In the era of high spatial-resolution multi-wavelength data, mapping the hot dust aroundSupermassive Black Holes is important for the efforts to achieve a complete picture of the dust role and distribution around thesecompact objects. In this work we propose a methodology to detect the hot dust emission in the proximity of Type 2 AGNs andmeasure its temperature using K-band spectra (휆푐 = 2.2 휇m). To achieve this, we have developed NIRDust, a Python package formodeling K-band spectra, estimate the dust temperature and characterize the involved uncertainties. We tested synthetic and realspectra in order to check the performance and suitability of the physical model over different types of data. Our tests on syntheticspectra demonstrated that the obtained results are influenced by the signal-to-noise ratio (S/N) of the input spectra. However, weaccurately characterized the uncertainties, which remained below ∼150 K for an average S/N per pixel exceeding 20. ApplyingNIRDust to NGC 5128 (Centaurus A), observed with the Gemini South Telescope, we estimated a dust temperature of 662 and667 K from Flamingos-2 spectra and 697 and 607 K from GNIRS spectra using two different approaches