TUNA Lunch Talk:

Darryl Leiter

Visiting Scientist, NRAO

A unified answer to the question "WHY ARE SOME QUASARS RADIO LOUD?"

March 4

12:10PM, Room 230, NRAO, Edgemont Road


Gravitational microlensing-reverberation observations and analysis, performed on two well-known Quasars (Q2237 - The Einstein Cross) and (Q0957 - The Twin), have revealed for the first time the detailed inner the structure of two quasars in significantly different spectral states(1,2). This has given us the unique opportunity to measure the detailed internal structure of a quasar (Q2237) in a radio quiet high-soft state, and compare it to a quasar (Q0957) in a radio loud low-hard state. When taken together we find that the observed differences in the spectral state structure of these two quasars can only be consistently understood as being due to the location of the inner radii of their accretion disks relative to the co-rotation radii of the Magnetospheric Eternally Collapsing Objects (MECO) in the centers of these quasars. The radiating structures observed in the two quasars are found to be associated with standard accretion disks and outer outflow structures, where the latter are the major source of UV-optical continuum radiation. While the observed inner accretion disk structure of the radio quiet quasar Q2237 by itself is consistent with either a MECO or a Black Hole, the observed inner structure of the radio loud quasar Q0957 can only be consistently explained by the action of the intrinsic magnetic propeller of a MECO on its surrounding accretion disk. Hence a simple and unified answer to the question ¿why are some quasars radio loud?¿ is found if the central compact objects within quasars are understood to be MECO, with radio loud and radio quiet spectral states similar to the case of Galactic Black Hole Candidates.

(1) Schild, Leiter, Robertson, Astr. Journal March (2008), (Astro-ph/0708.2422). (2) Schild, Leiter, Robertson, Astr. Journal, vol 132, pg 420, (2006).