Título
Detection of star streams and turbulence in nearby galaxies: power spectrum analysis of spitzer images
Autor
IVANIO PUERARI
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
Fourier transform power spectra of azimuthal scans in 33 galaxies imaged with the Infrared Array Camera on the Spitzer Space Telescope show an approximate power-law structure over a wide range of wavenumbers with a gradual steepening from 3.6 or 4.5μm to 8.0 μm, in the order of an increasing contribution from gas and dust. At radii with active star formation, the average of the slopes of the 8μm power spectra at intermédiate spatial frequencies is about the same for all galaxies, independent of spiral arm morphology. These power spectra are reminiscent of turbulence, although the 8μm slopes, averaging −2.0, are slightly steeper tan expected (−1.7). Reconstructed images using only these intermediate spatial frequencies at 4.5 μm show aging star complexes distorted by shear. These sheared features illustrate the transition from a hierarchical structure during star formation into azimuthal star streams like the Pleiades moving group in the Solar neighborhood. This is the first time that young star streams have been observed in spiral galaxies other than the Milky Way.
Editor
The Astrophysical Journal
Fecha de publicación
20 de marzo de 2009
Tipo de publicación
Artículo
Versión de la publicación
Versión aceptada
Recurso de información
Formato
application/pdf
Idioma
Inglés
Audiencia
Estudiantes
Investigadores
Público en general
Sugerencia de citación
Block, D. L., et al., (2009). Detection of star streams and turbulence in nearby galaxies: power spectrum analysis of spitzer images, The Astrophysical Journal. Vol.694(1):115–129
Repositorio Orígen
Repositorio Institucional del INAOE
Descargas
263