Ultraviolet emission from stellar populations within tidal tails: Catching the youngest galaxies in formation?

dc.contributor.authorGil de Paz, Armando
dc.contributor.authorotros, ...
dc.description© 2005. The American Astronomical Society. All rights reserved. Artículo firmado por 25 autores. GALEX is a NASA small explorer launched in 2003 April. We gratefully acknowledge NASA’s support for construction, operation, and science analysis for the GALEX mission, developed in cooperation with the Centre National d’Etudes Spatiales of France and the Korean Ministry of Science and Technology.
dc.description.abstractNew Galaxy Evolution Explorer (GALEX) observations have detected significant far-UV (FUV; 1530 Å) and near-UV (NUV; 2310 Å) emission from stellar substructures within the tidal tails of four ongoing galaxy mergers. The UV-bright regions are optically faint and are coincident with H I density enhancements. FUV emission is detected at any location where the H I surface density exceeds ~2 M_☉ pc^-2, and it is often detected in the absence of visible wavelength emission. UV luminosities of the brighter regions of the tidal tails imply masses of 10^6 to ~10^9 M_☉ in young stars in the tails, and H I luminosities imply similar H I masses. UV-optical colors of the tidal tails indicate stellar populations as young as a few megayears, and in all cases ages under 400 Myr. Most of the young stars in the tails formed in single bursts, rather than resulting from continuous star formation, and they formed in situ as the tails evolved. Star formation appears to be older near the parent galaxies and younger at increasing distances from the parent galaxy. This could be because the star formation occurs progressively along the tails, or because the star formation has been inhibited near the galaxy/tail interface. The youngest stellar concentrations, usually near the ends of long tidal tails, have masses comparable to confirmed tidal dwarf galaxies and may be newly forming galaxies undergoing their first burst of star formation.
dc.description.departmentDepto. de Física de la Tierra y Astrofísica
dc.description.facultyFac. de Ciencias Físicas
dc.identifier.citationBarnes, J. E., & Hernquist, L. E. 1992, ARA&A, 30, 705 Braine, J., Duc, P.-A., Lisenfeld, U., Charmandaris, V., Vallejo, O., Leon, S., & Brinks, E. 2001, A&A, 378, 51 Bruzual, G., & Charlot, S. 2003, MNRAS, 344, 1000 de Grijs, R., Lee, J. T., Clemencia Mora Herrera, M., Fritze-v. Alvensleben, U., & Anders, P. 2003, NewA, 8, 155 Duc, P.-A., & Mirabel, I. F. 1998, A&A, 333, 813 Haynes, M. P., & Giovanelli, R. 1991, ApJS, 77, 331 Hibbard, J. E., Vacca, W. D., & Yun, M. 2000, AJ, 119, 1130 Hibbard, J. E., & van Gorkom, J. H. 1996, AJ, 111, 655 Hibbard, J. E., van Gorkon, J. H., Rupen, M. P., & Schiminovich, D. 2001, in ASP Conf. Ser. 240, Gas and Galaxy Evolution, ed. J. E. Hibbard, M. P. Rupen, & J. H. van Gorkom (San Francisco: ASP), 659 Hibbard, J. E., et al. 2005, ApJ, 619, L87 Knierman, K. A., Gallagher, S. C., Charlton, J. C., Hunsberger, S. D., Whitmore, B., Kundu, A., Hibbard, J. E., & Zaritsky, D. 2003, AJ, 126, 1227 Kotilainen, J. K., Reunanen, J., Laine, S., & Ryder, S. D. 2001, A&A, 366, 439 Langston, G., & Teuben, P. 2001, in ASP Conf. Ser. 240, Gas and Galaxy Evolution, ed. J. E. Hibbard, M. P. Rupen, & J. H. van Gorkom (San Francisco: ASP), 862 Martin, D. C., et al. 2005, ApJ, 619, L1 McMahon, R. G., Walton, N. A., Irwin, M. J., Lewis, J. R., Bunclark, P. S., & Jones, D. H. 2001, NewA Rev., 45, 97 Mihos, J. C., & Hernquist, L. E. 1994, ApJ, 427, 112 ———. 1996, ApJ, 464, 641 Mirabel, I. F., Dottori, H., & Lutz, D. 1992, A&A, 256, L19 Nordgren, T. E., Chengalur, J. M., Salpeter, E. E., & Terzian, Y. 1997, AJ, 114, 913 Saviane, I., Hibbard, J. E., & Rich, R. M. 2004, AJ, 127, 660 Schlegel, D. J., Finkbeiner, D. P., & Davis, M. 1998, ApJ, 500, 525 Schombert, J. M., Wallin, J. F., & Struck-Marcell, C. 1990, AJ, 99, 497 Stanford, S. A., & Balcells, M. 1990, ApJ, 355, 59.
dc.journal.titleAstrophysical journal
dc.publisherAmerican Astronomical Society
dc.rights.accessRightsopen access
dc.subject.keywordInteracting galaxies
dc.subject.keywordMerging galaxies
dc.subject.keywordDwarf galaxies
dc.subject.ucmAstronomía (Física)
dc.titleUltraviolet emission from stellar populations within tidal tails: Catching the youngest galaxies in formation?
dc.typejournal article
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
198.13 KB
Adobe Portable Document Format