The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000 Å. II. Measurement of Foreground Zodiacal Light

Models of the zodiacal light are necessary to convert measured data taken from low Earth orbit into the radiation field outside the Solar System. The uncertainty in these models dominates the overall uncertainty in determining the extragalactic background light for wavelengths λ < 100 μm.

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Spectrophotometric measurement of the Extragalacic Background Light

Proceedings of the International Astronomical Union ◽

10.1017/s174392131200957x ◽

2011 ◽

Vol 7 (S284) ◽

pp. 429-436 ◽

Cited By ~ 3

Author(s):

Kalevi Mattila ◽

Kimmo Lehtinen ◽

Petri Väisänen ◽

Gerhard von Appen-Schnur ◽

Christoph Leinert

Keyword(s):

Scattered Light ◽

Spectral Lines ◽

Spectral Signature ◽

Zodiacal Light ◽

Differential Measurement ◽

Extragalactic Background Light ◽

Background Light ◽

The Difference ◽

Lower Limits ◽

Night Sky Brightness

AbstractThe Extragalactic Background Light (EBL) at UV, optical and NIR wavelengths consists of the integrated light of all unresolved galaxies along the line of sight plus any contributions by intergalactic matter including hypothetical decaying relic particles. The measurement of the EBL has turned out to be a tedious problem. This is because of the foreground components of the night sky brightness, much larger than the EBL itself: the Zodiacal Light (ZL), Integrated Starlight (ISL), Diffuse Galactic Light (DGL) and, for ground-based observations, the Airglow (AGL) and the tropospheric scattered light. We have been developing a method for the EBL measurement which utilises the screening effect of a dark nebula on the EBL. A differential measurement in the direction of a high-latitude dark nebula and its surrounding area provides a signal that is due to two components only, i.e. the EBL and the diffusely scattered ISL from the cloud. We present a progress report of this method where we are now utilising intermediate resolution spectroscopy with ESO's VLT telescope. We detect and remove the scattered ISL component by using its characteristic Fraunhofer line spectral signature. In contrast to the ISL, in the EBL spectrum all spectral lines are washed out. We present a high quality spectrum representing the difference between an opaque position within our target cloud and several clear OFF positions around the cloud. We derive a preliminary EBL value at 400 nm and an upper limit to the EBL at 520 nm. These values are in the same range as the EBL lower limits derived from galaxy counts.Unit: We will use in this paper the abbreviation 1 cgs = 10−9erg s−1cm−2sr−1Å−1

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Extragalactic background light measurements and applications

Royal Society Open Science ◽

10.1098/rsos.150555 ◽

2016 ◽

Vol 3 (3) ◽

pp. 150555 ◽

Cited By ~ 31

Author(s):

Asantha Cooray

Keyword(s):

Solar System ◽

Galaxy Formation ◽

Interplanetary Dust ◽

Absorption Feature ◽

Electromagnetic Spectrum ◽

Zodiacal Light ◽

Small Aperture ◽

Extragalactic Background Light ◽

Background Light ◽

Optical Background

This review covers the measurements related to the extragalactic background light intensity from γ-rays to radio in the electromagnetic spectrum over 20 decades in wavelength. The cosmic microwave background (CMB) remains the best measured spectrum with an accuracy better than 1%. The measurements related to the cosmic optical background (COB), centred at 1 μm, are impacted by the large zodiacal light associated with interplanetary dust in the inner Solar System. The best measurements of COB come from an indirect technique involving γ-ray spectra of bright blazars with an absorption feature resulting from pair-production off of COB photons. The cosmic infrared background (CIB) peaking at around 100 μm established an energetically important background with an intensity comparable to the optical background. This discovery paved the way for large aperture far-infrared and sub-millimetre observations resulting in the discovery of dusty, starbursting galaxies. Their role in galaxy formation and evolution remains an active area of research in modern-day astrophysics. The extreme UV (EUV) background remains mostly unexplored and will be a challenge to measure due to the high Galactic background and absorption of extragalactic photons by the intergalactic medium at these EUV/soft X-ray energies. We also summarize our understanding of the spatial anisotropies and angular power spectra of intensity fluctuations. We motivate a precise direct measurement of the COB between 0.1 and 5 μm using a small aperture telescope observing either from the outer Solar System, at distances of 5 AU or more, or out of the ecliptic plane. Other future applications include improving our understanding of the background at TeV energies and spectral distortions of CMB and CIB.

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Observations of the Near-Infrared Extragalactic Background Light

Symposium - International Astronomical Union ◽

10.1017/s0074180900225928 ◽

2001 ◽

Vol 204 ◽

pp. 87-100

Author(s):

Toshio Matsumoto

Keyword(s):

Large Scale ◽

Near Infrared ◽

High Redshift ◽

Far Infrared ◽

Zodiacal Light ◽

Extragalactic Background Light ◽

Background Light ◽

Infrared Telescope ◽

Total Energy Flux ◽

Infrared Spectrometer

We searched for the near infrared extragalactic background light (IREBL) in data from the Near Infrared Spectrometer (NIRS) on the Infrared Telescope in Space (IRTS). After subtracting the contribution of faint stars and a modeled zodiacal component, a significant isotropic emission is detected whose in-band flux amounts to ~ 30 nWm−2sr−1. This brightness is consistent with upper limits of COBE/DIRBE, but is significantly brighter than the integrated light of faint galaxies. The star subtraction analyses from DIRBE data show essentially the same results apart from the uncertainty in the model of the zodiacal light. A significant fluctuation of the sky brightness was also detected. A 2-point correlation analysis indicates that the fluctuations have a characteristic spatial structure of 100 ~ 200 arcmin. This could be an indication of the large scale structure at high redshift. Combined with the far infrared and submillimeter EBL, the total energy flux amounts to 50 ~ 80 nWm−2sr−1 which is so bright that unknown energy sources at high redshifts are required.

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Large angular scale fluctuations of near-infrared extragalactic background light based on the IRTS observations

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psz063 ◽

2019 ◽

Vol 71 (4) ◽

Cited By ~ 3

Author(s):

Min Gyu Kim ◽

Toshio Matsumoto ◽

Hyung Mok Lee ◽

Woong-Seob Jeong ◽

Kohji Tsumura ◽

...

Keyword(s):

Large Scale ◽

Near Infrared ◽

High Redshift ◽

Zodiacal Light ◽

Extragalactic Background Light ◽

Background Light ◽

Normal Galaxies ◽

Infrared Telescope ◽

Angular Scale ◽

Using Data

Abstract We measure the spatial fluctuations of the Near-Infrared Extragalactic Background Light (NIREBL) from 2° to 20° in angular scale at the 1.6 and $2.2\, \mu \mathrm{m}$ using data obtained with Near-Infrared Spectrometer (NIRS) on board the Infrared Telescope in Space (IRTS). The brightness of the NIREBL is estimated by subtracting foreground components such as zodiacal light, diffuse Galactic light, and integrated star light from the observed sky. The foreground components are estimated using well-established models and archive data. The NIREBL fluctuations for the 1.6 and $2.2\, \mu \mathrm{m}$ connect well toward the sub-degree scale measurements from previous studies. Overall, the fluctuations show a wide bump with a center at around 1° and the power decreases toward larger angular scales with nearly a single power-law spectrum (i.e., ${F[\sqrt{l(l+1)C_l/2\pi }]} \sim \theta ^{-1}]$, indicating that the large-scale power is dominated by the random spatial distribution of the sources. After examining several known sources, contributors such as normal galaxies, high-redshift objects, intra-halo light, and far-IR cosmic background, we conclude that the excess fluctuation at around the 1° scale cannot be explained by any of them.

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21. Light of the Night Sky

Transactions of the International Astronomical Union ◽

10.1017/s0251107x00004582 ◽

1982 ◽

Vol 18 (1) ◽

pp. 211-218

Author(s):

H. Tanabe ◽

R.H. Giese ◽

R. Dumont ◽

M. Harwit ◽

C. Leinert ◽

...

Keyword(s):

Light Source ◽

Large Distance ◽

Zodiacal Light ◽

Extragalactic Background Light ◽

Background Light ◽

Night Sky ◽

Light Components ◽

Celestial Sphere

The light of the night sky includes several components which spread all over the celestial sphere. These light components are terrestrial (airglow), interplanetary (zodiacal light), galactic (integrated starlight, diffuse galactic light) and extragalactic (extragalactic background light). Thus the study of nature of each light source, covering large distance, is pursued in different fields of astronomy. However, the techniques of measurement for respective components are similar and the knowledge of other lights is indispensable even in the study of a particular component.

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Background Light from Population III Stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900150636 ◽

1987 ◽

Vol 117 ◽

pp. 414-414

Author(s):

Jonathan C. McDowell

Keyword(s):

Dark Matter ◽

Background Radiation ◽

Large Fraction ◽

Rest Mass ◽

Critical Density ◽

Density Parameter ◽

Extragalactic Background Light ◽

Background Light ◽

Far Ultraviolet ◽

The Universe

It has been proposed (e.g. Carr, Bond and Arnett 1984) that the first generation of stars may have been Very Massive Objects (VMOs, of mass above 200 M⊙) which existed at large redshifts and left a large fraction of the mass of the universe in black hole remnants which now provide the dynamical ‘dark matter’. The radiation from these stars would be present today as extragalactic background light. For stars with density parameter Ω* which convert a fraction ϵ of their rest-mass to radiation at a redshift of z, the energy density of background radiation in units of the critical density is ΩR = εΩ* / (1+z). The VMOs would be far-ultraviolet sources with effective temperatures of 105 K. If the radiation is not absorbed, the constraints provided by measurements of background radiation imply (for H =50 km/s/Mpc) that the stars cannot close the universe unless they formed at a redshift of 40 or more. To provide the dark matter (of one-tenth closure density) the optical limits imply that they must have existed at redshifts above 25.

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