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MAGIC physics: results and goals
All results from MAGIC observations are summarized in the
results pages.
The very latest news are in the
MAGIC home page. You may also consult the
MAGIC publications pages.
The various objects that constitute the hunting ground for Cherenkov
telescopes are outlined below.
Artist's view of an Active Galactic Nucleus
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Active galactic nuclei (AGNs) are
extragalactic compact regions, typically supermassive black holes, in the centre of
galaxies. They exhibit high luminosity over most of the electromagnetic spectrum.
The observed radiation from AGNs comes from the accretion of matter
onto a disk surrounding the black hole. The disk typically rotates,
and develops jets along the axis of rotation. Inside the jet,
particles are accelerated to relativistic velocities.
AGN are the most luminous persistent sources of electromagnetic radiation
in the universe.
Blazars are AGNs with their jet pointing in the general
direction of the Earth. They are characterized by rapid variability. Many blazars
show superluminal features in the jet close to the source, probably due to
relativistic shock fronts.
Many MAGIC observations concern blazars:
BL Lacertae, the source which gave its name to an entire subclass of blazars,
Markarian 501 and Markarian 421, the first blazars to be seen in high-energy gamma-rays,
and many others, including a scan over several potential sources.
Some blazar observations also are interesting for special properties of the source.
Particularly distant objects, for instance,
can serve to study the absorption properties of the space between the
source and our galaxy. See more below under 'Cosmology'.
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Binary systems are made of a heavy star and a black hole
accreting mass from its companion. They are known for the powerful emission of
temporally and spectrally variable X-ray radiation.
MAGIC has detected a rapidly varying signal from a known binary system,
the source Cygnus X-1. This is the first detection of gamma-rays
of very high energy emitted from a black hole of stellar mass.
Find more details on the Cyg X-1 detection in the MAGIC results.
An earlier result, published in 2006 in Science Magazine, concerns the detection of
gamma-rays with some clear signs of periodicity from the binary system LSI +61 303.
That source is visible only in a short window of phase, and the maximum in gamma-rays
does not coincide with the maximum observed in periodic radio outbursts.
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An X-ray binary system
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A Supernova remnant: Kepler's supernova SN1604 seen in X-rays by Chandra
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Supernova remnants (SNRs) are typically shell-shaped expanding
remains caused by a supernova; a supernova is the final explosion of a massive star, of
more than eight solar masses. It causes a brief burst of radiation that may
outshine the entire host galaxy, before fading from view over several weeks or months.
During this short interval, a supernova can radiate as much energy as the Sun would emit
over 10 billion years. The explosion expels much or all of a star's material at high
velocity, driving a shock wave into the surrounding interstellar medium, where it
sweeps up an expanding shell of gas and dust called a supernova remnant.
Find more details of MAGIC-observed supernovae in the
MAGIC result pages.
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Cosmology: Some basic questions about the
basic properties of the Universe, and its history, may also find at least partial
answers in observations made by Cherenkov telescopes.
The sky seen in gamma-rays could provide some major surprises.
Like, for instance, in Dark Matter.
From multiple measurements of galaxy movements it looks very likely that
Dark Matter, matter that does not interact other than by the gravitational
force, makes up a large fraction of the matter in the Universe, five or six
times more than ordinary observable matter. If Dark Matter
annihilates into gamma-rays, as some theories predict, then the MAGIC telescope
could be the first telescope to detect them. First MAGIC observations of the
dwarf galaxy Draco, which is a candidate source for Dark Matter,
did set an upper limit for a signal; for more details, see the MAGIC result pages.
Or there is the intergalactic space:
MAGIC has observed the most distant gamma-ray emitters known, 3C 279 and
1ES 1011. Due to their large distances, such sources permit to extract
information about the space separating the source from our galaxy.
And, due to the billions of years the light from such sources has taken to
reach us, even information about the evolution of space may be obtained.
Finally, there is Quantum Gravity:
A very special possibility was offered by observation of a short outburst
of the blazar Markarian 501,
which seems to show some energy dependence of gamma arrival times,
permitting speculations about possible quantum gravity effects.
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A simulation of the filament-like distribution of Dark Matter in the Universe
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New objects:
A new source of very high energy gamma-ray emission was detected by MAGIC,
located close to the Galactic Plane, coincident with the supernova remnant IC443.
It has been named MAGIC J0616+225. The emission could be related to the
molecular environment found in the region of IC443.
For more details on J0616, look in the MAGIC result pages.
A finding of some serendipity
is the source that MAGIC discovered near Cygnus X-3. Due to their small
opening angle, Cherenkov telescopes do not usually see signals that have not been
conjectured previously by observations at other wavelengths. In this case,
the discovered object is near Cygnus X-3, and it is in studying
this well-known X-ray source that this (unidentified and presently unclassifyable)
object was seen. For more details, see the Cyg X-3 results in the MAGIC result pages.
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MAGIC observations near Cygnus X-3
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More on MAGIC physics
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