Diffuse Galactic Backgrounds with SPHEREx: A Pilot Study of Background Modeling and Its Impact on Extinction
Abstract
We present a spectral analysis of diffuse Galactic background emission using SPHEREx data in a pilot Galactic-plane field, where uncertainty in the estimation of the diffuse infrared background is a major source of systematic uncertainty in extinction studies at near- and mid-infrared wavelengths. We construct channel-resolved background maps across the 0.75--5~μm range using a Large Median Filter approach and then carry the extinction analysis forward only for the cleaner long-wavelength subset at λ≥ 3 μm. In the present field, comparison against an earlier masked-median background model gives a median channel-by-channel background difference of about 6\% and a maximum change of |Δτnorm|≃ 7.4 near 3.205~μm, underscoring the importance of wavelength-dependent background modeling. These results demonstrate that spectral mapping with SPHEREx provides a practical framework for controlling diffuse background systematics and enables improved constraints on dust opacity and extinction in the Galactic plane.
Related
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BibTeX
@misc{lim2026diffuse,
title = {{Diffuse Galactic Backgrounds with SPHEREx: A Pilot Study of Background Modeling and Its Impact on Extinction}},
author = {Wanggi Lim and Jae Hwan Kang and Keunho J. Kim and Young-Jun Kim},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.04780},
eprint = {2610.04780},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.04780},
}
RIS
TY - UNPB
TI - Diffuse Galactic Backgrounds with SPHEREx: A Pilot Study of Background Modeling and Its Impact on Extinction
AU - Wanggi Lim
AU - Jae Hwan Kang
AU - Keunho J. Kim
AU - Young-Jun Kim
PY - 2026
DA - 2026/10/03
PB - arXiv
DO - 10.48550/arxiv.2610.04780
UR - https://arxiv.org/abs/2610.04780
AB - We present a spectral analysis of diffuse Galactic background emission using SPHEREx data in a pilot Galactic-plane field, where uncertainty in the estimation of the diffuse infrared background is a major source of systematic uncertainty in extinction studies at near- and mid-infrared wavelengths. We construct channel-resolved background maps across the 0.75--5~μm range using a Large Median Filter approach and then carry the extinction analysis forward only for the cleaner long-wavelength subset at λ≥ 3 μm. In the present field, comparison against an earlier masked-median background model gives a median channel-by-channel background difference of about 6\% and a maximum change of |Δτ_norm|≃ 7.4 near 3.205~μm, underscoring the importance of wavelength-dependent background modeling. These results demonstrate that spectral mapping with SPHEREx provides a practical framework for controlling diffuse background systematics and enables improved constraints on dust opacity and extinction in the Galactic plane.
ER -