Clear evidence for the early triggering of a luminous quasar-like AGN in a major, gas rich merger

Дата и время публикации : 2013-11-27T09:35:46Z

Авторы публикации и институты :
Patricia S. Bessiere
Clive N. Tadhunter
Cristina Ramos Almeida
Montserrat Villar Martin

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 10 Pages, 4 figures, accepted for publication in MNRAS
Первичная категория: astro-ph.CO

Все категории : astro-ph.CO

Краткий обзор статьи: We present deep, intermediate resolution, long slit Gemini GMOS-S optical spectra of the SDSS type II quasar J002531-104022, which is a highly disturbed system currently undergoing a major merger event. We use these data to model the ages and reddenings of the stellar populations in three distinct spatial regions and find a remarkable uniformity in the properties of the young stellar populations (YSP) that dominate the optical spectra. The YSPs are all found to have relatively young ages (tysp < 40$ Myr), strongly implying that the latest episode of star formation and quasar activity have been triggered quasi-simultaneously. The lack of reddening deduced from both continuum modelling and the measured Balmer decrements (E(B-V) <0.3) suggests that starburst and/or AGN induced outflows have already effectively removed a substantial proportion of the gas and dust from the central region. These findings starkly contrast with model predictions which suggest an offset of a few 100 Myr between the peak of merger induced star formation and the emergence of the optically visible quasar activity. Based on our stellar population fits we also show that the total stellar mass is in the range (4 – 17) X 10^10 solar masses, lower than typically found for quasar host galaxies.

Category: Physics