The near infrared airglow continuum conundrum. Constraints for ground-based faint object spectroscopy

Abstract

The airglow continuum in the near infrared is a challenge to quantify due to its faintness, and the grating scattered light from atmospheric hydroxyl (OH) emission lines. Despite its faintness, the airglow continuum sets the fundamental limits for ground-based spectroscopy of faint targets, and makes the difference between ground and space-based observation in the interline regions between atmospheric emission lines. We aim to quantify the level of airglow continuum radiance in the VIS -- NIR wavelength range observable with silicon photodetectors for the site Observatorio del Roque de los Muchachos in a way that our measurement will not be biased by the grating scattered light. We aim to do this by measuring the airglow continuum radiance with a minimal and controlled contamination from the broad instrumental scattering wings caused by the bright atmospheric OH lines. We measure the airglow continuum radiance with longslit $\lambda /\Delta \lambda \sim 4000$ spectrograph in $\sim$100Å wide narrow band passes centered at 6720, 7700, 8700 and 10500Å (in line with the R, I, and Z broadbands) with the 2.5-meter Nordic Optical Telescope under photometric dark sky conditions. The bandpasses are chosen to be as clean as possible from atmospheric absorption and the OH line emission keeping the radiation reaching the grating surface at minimum. We observe the zenith equivalent airglow continuum to be 22.5mag/arcsec2 at 6720Å band, and 22mag/arcsec2 at 8700Å. We derive upper limits of 22mag/arcsec2 at 7700Å due to difficulty to find a clean part of spectrum for measurement, and 20.8mag/arcsec2 at 10500Å due to low system sensitivity. Within measurement errors and the natural variability expected for the airglow emission our results for the Observatorio del Roque de los Muchachos are comparable to values reported for other major observatory sites. (abridged)

arXiv comment18 pages, 12 figures, 5 tables. Accepted for publication in A&A

References in corpus (31)

• The Great Observatories Origins Deep Survey: Initial Results From Optical and Near-Infrared Imaging
• Cosmic-Ray Rejection by Laplacian Edge Detection
• The Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry
• The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: I. Limits and Detections
• The Pan-STARRS1 Database and Data Products
• The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: II. Model of the Interplanetary Dust Cloud
• COSMOS : Hubble Space Telescope Observations
• COSMOS2020: A panchromatic view of the Universe to $z\sim 10$ from two complementary catalogs
• An atmospheric radiation model for Cerro Paranal. I. The optical spectral range
• The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: IV. Cosmological Implications
• An advanced scattered moonlight model for Cerro Paranal
• The COBE Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background: III. Separation of Galactic Emission from the Infrared Sky Brightness
• Infrared Emission from the Radio Supernebula in NGC 5253: A Proto-Globular Cluster?
• Angular Power Spectra of the COBE DIRBE Maps
• The Dancing Sky: 6 years of night sky observations at Cerro Paranal
• The case for OH suppression at near-infrared wavelengths
• The Luminosity Function of Lyman alpha Emitters at Redshift z=7.7
• Suppression of the near-infrared OH night sky lines with fibre Bragg gratings - first results
• Optical Night-Sky Brightness at Mauna Kea over the Course of a Complete Sunspot Cycle
• Lines and continuum sky emission in the near infrared: observational constraints from deep high spectral resolution spectra with GIANO-TNG
• Ultraviolet to optical diffuse sky emission as seen by the Hubble Space Telescope Faint Object Spectrograph
• OHS: OH-airglow Suppressor for the Subaru Telescope
• 15 years of VLT/UVES OH intensities and temperatures in comparison with TIMED/SABER data
• First demonstration of OH suppression in a high efficiency near-infrared spectrograph
• A Calibrated Measurement of the Near-IR Continuum Sky Brightness Using Magellan/FIRE
• SKYSURF: Constraints on Zodiacal Light and Extragalactic Background Light through Panchromatic HST All-Sky Surface-Brightness Measurements: I. Survey Overview and Methods
• The nature of the near-infrared interline sky background using fibre Bragg grating OH suppression
• A GIANO-TNG high resolution IR spectrum of the airglow emission
• Low-Resolution Spectrum of the Zodiacal Light with AKARI InfraRed Camera
• Spatial and Temporal Stability of Airglow Measured in the Meinel Band Window at 1191.3 nm
• Structure, variability, and origin of the low-latitude nightglow continuum between 300 and 1,800 nm: Evidence for HO${}_2$ emission in the near-infrared