Getting to the bottom of the lagoon - Dust, magnetism, and star formation

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/168937· OSTI ID:6596572

Mccall, M L; Richer, M G; Visvanathan, N ^[1]

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1. York Univ., North York (Canada) Toronto Univ. (Canada) Mount Stromlo and Siding Spring Observatories, Canberra (Australia)

A V-band polarimetric survey of stars associated with the Lagoon Nebula (M8; NGC 6523) and the embedded cluster NGC 6530 has been conducted. The data have been combined with existing photometric and spectroscopic observations in order to study the dust in the immediate vicinity and to investigate the alignment of magnetic field lines with identifiable symmetry axes. Using the cluster method, it has been possible to separate multiple stars from single stars and thereby derive acccurate values for the ratio of total to selective extinction and the distance modulus. The value of R for the associated dust is 4.6 + or - 0.3. Anomalous reddening is a characteristic of the region, not just Herschel 36. Electric vectors show a high degree of alignment perpendicular to the direction of the extension of the large-scale distributions of ionized gas and massive stars. The overall collapse of molecular gas appears to have been asymmetrical, proceeding most rapidly along a direction parallel to magnetic field lines. A lot of the dust mixed with the ionized gas has been destroyed, so the large-scale uniformity of reddening laws and polarization position angles indicates that much of the dust responsible for extinction and polarization is associated with neutral gas. 69 refs.

• OSTI ID: 6596572
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 357; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640102 -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ATMOSPHERES
COSMIC DUST
COSMIC GASES
CRYSTAL STRUCTURE
DUSTS
FLUIDS
GASES
GRAIN SIZE
IDENTIFICATION SYSTEMS
INTERSTELLAR MAGNETIC FIELDS
INTERSTELLAR SPACE
IONIZED GASES
MAGNETIC FIELDS
MICROSTRUCTURE
NEBULAE
PHOTOMETRY
POLARIMETRY
POLARIZATION
SIZE
SPACE
SPECTROSCOPY
STAR CLUSTERS
STAR EVOLUTION
STARS
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR RADIATION