The nature of blue cores in spheroids

Simple item page
dc.contributor.authorMenanteau, F
dc.contributor.authorMartel, AR
dc.contributor.authorTozzi, P
dc.contributor.authorFrye, B
dc.contributor.authorFord, HC
dc.contributor.authorInfante, L
dc.contributor.authorBenítez, N
dc.contributor.authorGalaz, G
dc.contributor.authorCoe, D
dc.contributor.authorIllingworth, GD
dc.contributor.authorHartig, GF
dc.contributor.authorClampin, M
dc.date.accessioned2025-01-21T01:07:09Z
dc.date.available2025-01-21T01:07:09Z
dc.date.issued2005
dc.description.abstractWe investigate the physical nature of blue cores in early-type galaxies through the first multiwavelength analysis of a serendipitously discovered field blue-nucleated spheroid in the background of the deep Hubble Space Telescope ACS/WFC griz multicolor observations of the cluster A1689. The resolved g - r, r - i, and i - z color maps reveal a prominent blue core identifying this galaxy as a "typical'' case study, exhibiting variations of 0.5 - 1.0 mag in color between the center and the outer regions, opposite to the expectations of reddened metallicity- induced gradients in passively evolved elliptical galaxies. From a Magellan-Clay telescope spectrum we secure the galaxy redshift at z = 0.624. We find a strong X-ray source coincident with the spheroid galaxy. Spectral features and a high X-ray luminosity indicate the presence of an active galactic nucleus (AGN) in the galaxy. However, a comparison of the X-ray luminosity to a sample derived from the Chandra Deep Field - South displays L-X to be comparable to type 1/QSO galaxies while the optical flux is consistent with a normal star-forming galaxy. We conclude that the galaxy's nonthermal component dominates at high-energy wavelengths, while we associate the spheroid blue light with the stellar spectrum of normal star-forming galaxies. We argue for a probable association between the presence of blue cores in spheroids and AGN activity.
dc.fuente.origenWOS
dc.identifier.eissn1538-4357
dc.identifier.issn0004-637X
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/96283
dc.identifier.wosidWOS:000227405800012
dc.issue.numero2
dc.language.isoen
dc.pagina.final702
dc.pagina.inicio697
dc.revistaAstrophysical journal
dc.rightsacceso restringido
dc.subjectgalaxies : active
dc.subjectgalaxies : elliptical and lenticular, cD
dc.subjectX-rays : galaxies
dc.titleThe nature of blue cores in spheroids
dc.typeartículo
dc.volumen620
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas