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EARLY IMPORTANCE. “The submm galaxies generate a significant fraction of the energy output of all the galaxies in the early Universe.” (Submm = submillimeter). https://lnkd.in/dAkZ_ejH View in LinkedIn

COSMIC TIME SCALES. “The rapid enrichment by metals and dust at very high redshift discussed above suggests that quasar host galaxies could have undergone intense episodes of star formation. Similar chemical abundances are typically found in local galaxies which, however, evolved on longer time scales.” https://lnkd.in/dHcpNrnR View in LinkedIn

SUBMILLIMETER GALAXIES. “A cosmologically significant population of very luminous high-redshift galaxies has recently been discovered at submillimeter (submm) wavelengths.” https://lnkd.in/dAkZ_ejH View in LinkedIn

QUASAR ROLE. “Supermassive black holes (SMBHs) at the centres of galaxies are known to actively accrete, forming so-called `active galactic nuclei' (AGN) or `quasars'. These AGN are believed to feed back energy into their host galaxies, regulating star formation and the growth of the SMBH itself.” https://lnkd.in/d9BB4wDY View in LinkedIn

“THE POWER SOURCE for dusty galaxies. About 99% of the energy released by galaxies in the submm and far-IR wavebands is produced by thermal emission from dust grains; the remainder comes from fine-structure atomic and molecular rotational line emission. However, the source of the energy to power this emission by heating dust is often unclear.” (IR = infrared; Submm == submillimeter wavelengths). https://lnkd.in/dAkZ_ejH View in LinkedIn

HIGH ENERGY SOURCES. “The first extragalactic submm/mm surveys using SCUBA and MAMBO revealed a population of very luminous high-redshift galaxies, which as a population, were responsible for the release of a significant fraction of the energy generated by all galaxies over the history of the Universe.” (Submm == submillimeter wavelengths). https://lnkd.in/dAkZ_ejH View in LinkedIn

CHALLENGING WAVELENGTHS. “With the possible exception of the hardest X-ray wavebands, studies of distant galaxies in the submm waveband remained elusive for the longest period.” The many reasons for this difficulty are discussed. (Submm == submillimeter wavelengths). https://lnkd.in/dAkZ_ejH View in LinkedIn

CLEAR SEPARATION. “The detection of submm radiation from distant galaxies is one of the most recent developments in observational cosmology, and has finally brought this region of the electromagnetic spectrum into use for making cosmological observations not directly connected with the cosmic microwave background (CMB).” (Submm == submillimeter wavelengths). https://lnkd.in/dAkZ_ejH View in LinkedIn

NOVEL TERRITORY. “This review discusses the results of a new type of direct observation of the galaxy formation process, made possible by the development of powerful new radiation detectors sensitive to wavelengths in the range 200 µm to about 1 mm: the submillimeter (submm) waveband.” (Submm == submillimeter wavelengths). https://lnkd.in/dAkZ_ejH View in LinkedIn

GEOMETRY DEPENDENT. “If the geometry of absorbing and scattering material is known or assumed, then radiative transfer models can be used to predict the SED of a galaxy, which should differ depending on whether the source of heating is a very small AGN with a very hard UV SED, or a more extended, softer-spectrum nuclear star-forming region. Note that the results are expected to be very sensitive to the assumed geometry.” (AGN = active galactic nuclei; UV = ultraviolet; SED = spectral energy distributions). https://lnkd.in/dAkZ_ejH View in LinkedIn