Measurements of the mean diffuse galactic light spectrum in the 0.95 {\mu}m to 1.65 {\mu}m band from CIBER

TL;DR

This study measures the near-infrared diffuse galactic light spectrum between 0.95 and 1.65 micrometers using CIBER, revealing a featureless continuum consistent with scattered starlight models and extending previous optical and infrared measurements.

Contribution

First measurement of the DGL spectrum in the 0.95-1.65 μm range with absolute calibration, correlating spectral data with dust maps to isolate the DGL component.

Findings

DGL spectrum shows no resolved features.

Consistent with models of scattered starlight.

Extends previous optical and infrared measurements.

Abstract

We report measurements of the Diffuse Galactic Light (DGL) spectrum in the near-infrared, spanning the wavelength range 0.95-1.65 {\mu}m by the Cosmic Infrared Background ExpeRiment (CIBER). Using the low-resolution spectrometer (LRS) calibrated for absolute spectro-photometry, we acquired long-slit spectral images of the total diffuse sky brightness towards four high-latitude fields spread over four sounding rocket flights. To separate the DGL spectrum from the total sky brightness, we correlated the spectral images with a 100 {\mu}m intensity map, which traces the dust column density in optically thin regions. The measured DGL spectrum shows no resolved features and is consistent with other DGL measurements in the optical and at near-infrared wavelengths longer than 1.8 {\mu}m. Our result implies that the continuum is consistently reproduced by models of scattered starlight in the Rayleigh scattering regime with a few large grains.