[SEMINARI] [Dos Seminaris] M87: A Laboratory for Astrophysical Processes; ALMA: Observing the Cold Universe

[Enric Marco]

M87: A Laboratory for Astrophysical Processes

Philip E. Hardee

University of Alabama

Seminari del Departament d'Astronomia i Astrofisica

Dijous 10 desembre 2009

15:00

Resum

The accretion of matter onto a massive black hole is believed to feed 
the relativistic plasma jets found in many active galactic nuclei (AGN). 
Some AGN accelerate particles to energies exceeding 10^{12} electron 
Volts (eV) and are bright sources of very-high-energy (VHE) gamma-ray 
emission. However, it is not yet known where the VHE emission originates 
or what provides the mechanism for particle acceleration to very high 
energies. Firstly I report on radio and VHE observations of the radio 
galaxy M 87 that reveal a period of extremely strong gamma-ray flares 
accompanied by a strong increase in the radio flux. The results imply 
that particles must be accelerated to very high energies in the 
immediate vicinity of the black hole. Secondly I present new numerical 
simulation studies of the current driven instability (CDI) that could 
provide conversion of magnetic energy to plasma jet bulk kinetic energy 
and could also provide particle acceleration to the very high energies 
required by the observed emission.

http://celeste.uv.es/daa/seminari.php?id=1016

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ALMA: Observing the Cold Universe

Robert Laing

European Southern Observatory

Seminari del Departament d'Astronomia i Astrofisica

Divendres 11 desembre 2009

12:00

Resum

ALMA, the Atacama Large Millimetre/Sub-millimetre Array, is the largest 
current project in ground-based astronomy. It is an aperture synthesis 
array, optimized for high frequencies and currently under construction 
at a high, dry site in the Atacama desert of Northern Chile. When 
complete, it will provide unprecedented sensitivity, spatial resolution 
and imaging fidelity over the frequency range from 30 - 950 GHz. I will 
describe the key scientific goals of the project and outline its 
technical design. Interferometric observations with the first two ALMA 
antennas have recently been made, and construction is progressing 
rapidly. I will give an update on the current status and preparations 
for Early Science.

http://celeste.uv.es/daa/seminari.php?id=1017

-- 
/------------------------------------\
 Dr. Enric Marco
 Departament d'Astronomia i Astrofísica
 Facultat de Física
 Universitat de València
 C/  Dr. Moliner, 50
 46100 Burjassot, Spain
 Phone: (34)-96-354-3069
 Fax:(34)-96-354-3084
 enric.marco en uv.es
 http://www.uv.es/marco
 http://www.uv.es/aulaastronomia
 http://www.uv.es/daa
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