Skip to main content

ORIGIN OF RADIO EMISSION IN RADIO-QUIET QUASARS

Image Credit: NASA/Goddard Space Flight Center

Radio emission of radio-quiet quasars may be due to stars formation in the quasar host galaxy, to a jet launched by the supermassive black hole, or to relativistic particles accelerated in a wide-angle radiatively-driven outflow.


Recently some authors (Zakamska et al 2016) examine whether radio emission from radio-quiet quasars is a byproduct of stair formation in their hosts. They find that even the most generously computed star formation rates are insufficient to explain the observed radio emission, by about an order of magnitude. They cannot distinguish between radio emission due to compact weak jets and radio emission due to wide angle winds. The problem of distinguishing radio emission from compact jets from radio emission as a bi-product of radiatively driven has proven espexially difficult because the two mechanisms are similar in terms of energetics.


Read more>>
http://arxiv.org/pdf/1511.00013v2.pdf
http://mnras.oxfordjournals.org/content/455/4/4191.abstract

Etichette:

Comments

Post a Comment

Popular posts from this blog

QUASARS AND THE COSMIC REIONIZATION

Credit: NASA/ESA Recently it has been suggested that quasars can be primarily responsible for the reionization of the universe.
Post a Comment
Read more

BOUNCING BLACK HOLES

Image: Illustration of a dusty supermassive black hole. Credit: ESA/NASA, the AVO project and Paolo Padovani Black holes could be bouncing stars as a consequence of quantum gravity: when the density of matter becomes high enough, quantum gravity effects generate sufficient pressure to compensate the matter's weight, the collapse ends, and matter bounces out. In a black hole, matter's collapse could stop before the central singularity is formed.
Post a Comment
Read more

SUPERNOVAE FROM WD-WD DIRECT COLLISIONS

Image: Supernova remnant N 63A. Credit: NASA/ESA/HEIC and The Hubble Heritage Team (STScI/AURA) Models for supernovae (SNe) related to thermonuclear explosions of white dwarfs (WDs) have been extensively studied over the last few decades, mostly focusing on single degenerate (accretion of material of a WD) and double degenerate (WD-WD merger) scenarios.
Post a Comment
Read more