Infrared Emission at High Galactic Latitude

Results obtained with the Infrared Astronomy Satellite (IRAS) on the IR emission at high galactic latitude are reviewed. We present evidence for the detection of galactic emission at 12, 25, 60, and 100 μm. We describe the morphology of this emission and summarize work on the correlation of IR cirrus with H I, CO, and optical emission. We discuss the contribution of the neutral atomic, ionized, and molecular gas to the total IR emission and the contribution of different components of interstellar dust to the emission seen at different wavelengths.

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Correlation of Infrared Emission with H I and CO Gas in the High Latitude Cloud Area L1642

Symposium - International Astronomical Union ◽

10.1017/s0074180900240680 ◽

1990 ◽

Vol 139 ◽

pp. 216-217

Author(s):

T. Liljeström ◽

R. Laureijs

Keyword(s):

Galactic Plane ◽

Molecular Data ◽

Infrared Emission ◽

Galactic Latitude ◽

Optical Extinction ◽

Suitable Candidate ◽

High Galactic Latitude ◽

Dust Clouds ◽

Background Gas ◽

Co Gas

The high-galactic-latitude cloud L1642 (l = 210.8°, b = −36.7°) is a suitable candidate to relate IR measurements with atomic and molecular data because it has a reasonable size with respect to the rather poor (IRAS) IR resolution, a moderate optical extinction and an isolated location in the direction towards the galactic anticenter. The exceptionally high galactic latitude of −36.7° implies that L1642 is some 60 pc below the galactic plane (if r ≈ 100 pc is adopted for its distance). L1642 is thus sufficiently far off the galactic plane to minimize the confusion by background gas and dust clouds.

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ERE from Graphene Oxide in the ISM. A possible link to IOM?

10.5194/epsc2020-945 ◽

2020 ◽

Author(s):

Peter Sarre

Keyword(s):

Graphene Oxide ◽

Organic Material ◽

Interstellar Dust ◽

Emission Spectra ◽

Optical Emission ◽

Interplanetary Dust ◽

Infrared Emission ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Infrared Space Observatory

Dust particles play a major role in the formation, evolution and chemistry of interstellar clouds, stars, and planetary systems. Commonly identified forms include amorphous and crystalline carbon-rich particles and silicates. Also present in many astrophysical environments are polycyclic aromatic hydrocarbons (PAHs), detected through their infrared emission, and which are essentially small flakes of graphene. Astronomical observations over the past four decades have revealed a widespread unassigned &#8216;extended red emission&#8217; (ERE) feature which is attributed to luminescence of dust grains. A luminescence feature with similar characteristics to ERE has been found in organic material in interplanetary dust particles and carbonaceous chondrites. &#160; There is a strong similarity between laboratory optical emission spectra of graphene oxide (GO) and ERE, leading to this proposal that emission from GO nanoparticles is the origin of ERE and that heteroatom-containing PAH structures are a significant component of interstellar dust. The proposal is supported by infrared emission features detected by the Infrared Space Observatory (ISO) and the Spitzer Space Telescope. &#160; Insoluble Organic Material (IOM) has a chemical structure with some similarities to graphene oxide. &#160;It is suggested this may contribute to the discussion as to whether IOM has an origin in the interstellar medium or the solar nebula, or some combination.

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Graphene oxide nanoparticles in the interstellar medium

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slz131 ◽

2019 ◽

Vol 490 (1) ◽

pp. L17-L20 ◽

Cited By ~ 5

Author(s):

P J Sarre

Keyword(s):

Graphene Oxide ◽

Interstellar Dust ◽

Emission Spectra ◽

Optical Emission ◽

Infrared Emission ◽

Dust Particles ◽

Infrared Space Observatory ◽

Interstellar Clouds ◽

General Acceptance ◽

Extended Red Emission

ABSTRACT Dust particles play a major role in the formation, evolution and chemistry of interstellar clouds, stars, and planetary systems. Commonly identified forms include amorphous and crystalline carbon-rich particles and silicates. Also present in many astrophysical environments are polycyclic aromatic hydrocarbons (PAHs), detected through their infrared emission, and which are essentially small flakes of graphene. Astronomical observations over the past four decades have revealed a widespread unassigned ‘extended red emission’ (ERE) feature which is attributed to luminescence of dust grains. Numerous potential carriers for ERE have been proposed but none has gained general acceptance. In this Letter it is shown that there is a strong similarity between laboratory optical emission spectra of graphene oxide (GO) and ERE, leading to this proposal that emission from GO nanoparticles is the origin of ERE and that these are a significant component of interstellar dust. The proposal is supported by infrared emission features detected by the Infrared Space Observatory (ISO) and the Spitzer Space Telescope.

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Distribution of IRAS Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900159194 ◽

1987 ◽

Vol 124 ◽

pp. 229-245

Author(s):

Michael Rowan-Robinson

Keyword(s):

Interstellar Dust ◽

Local Group ◽

Big Bang ◽

Galactic Latitude ◽

Gravitational Acceleration ◽

Microwave Background ◽

High Galactic Latitude ◽

Galaxy Surveys ◽

Infrared Wavelengths ◽

The Universe

Infrared wavelengths are free of several of the problems that plague optical galaxy surveys. At high galactic latitude ≥99% of 60μ sources in the IRAS Point Source Catalog, after deletion of obvious stars, are galaxies. At lower latitudes care has to be taken to avoid confusion with emission from interstellar dust (the ‘cirrus’). IRAS galaxies have been used to determined the direction of the gravitational acceleration acting on the Local Group due to galaxies and clusters within about 200 Mpc. This agrees well with the direction of the microwave background dipole. The density of matter in the universe, distributed like IRAS galaxies, needed to account for the observed velocity of the Local Group, corresponds to Ωo = 1.0 ± 0.2. In the standard hot Big Bang model, 90–95% of this matter would have to be non-baryonic.IRAS galaxies are significantly less clustered than optically selected galaxy samples.

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Infrared emission and optical scattering by the high galactic latitude dust cloud L1642

Advances in Space Research ◽

10.1016/0273-1177(86)90208-5 ◽

1986 ◽

Vol 6 (7) ◽

pp. 37-41

Author(s):

R.J. Laureijs ◽

K. Mattila ◽

G. Schnur

Keyword(s):

Dust Cloud ◽

Infrared Emission ◽

Optical Scattering ◽

Galactic Latitude ◽

High Galactic Latitude

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Extended Infrared Emission in Seyfert Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900155019 ◽

1987 ◽

Vol 121 ◽

pp. 127-129

Author(s):

J.M. Rodriguez Espinosa ◽

R.J. Rudy

Keyword(s):

Star Formation ◽

Single Photon ◽

Optical Emission ◽

Far Infrared ◽

Seyfert Galaxies ◽

Infrared Emission ◽

Conclusive Evidence ◽

Small Grains ◽

Almost All ◽

Ir Emission

We have analyzed far-IR (IRAS) data for a sample of optically selected Seyfert galaxies. The far-infrared emission is uncorrelated, or at best weakly correlated, with the UV-optical emission from these sources. We find the far-IR emission to be extended in a number of objects. We discuss the possibility that Seyfert galaxies are undergoing circumnuclear bursts of star formation. For comparison with the large aperture IRAS data we have also obtained new ground-based measurements at 10 and 20 μm for a sample of 17 Seyfert galaxies. Conclusive evidence for extended 10 and 20 μm emission is seen in 7 out of 17 objects. In addition, almost all of the objects have ground-based fluxes which are smaller than those measured by IRAS. Finally, for five objects the emission appears to be more extended at 10 μm than at 20 μm. This would be expected if the 10 μm emission arose, in part, from a population of very small grains for which single photon heating is important.

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