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MAGIC (telescope)
Encyclopedia
MAGIC is a system of two Imaging Atmospheric Cherenkov telescope
s situated at the Roque de los Muchachos Observatory
on La Palma
, one of the Canary Islands
, at about 2200 m above sea level. MAGIC detects particle showers released by gamma rays, using the Cherenkov radiation
, i.e., faint
light radiated by the charged particles in the showers. With a diameter of 17 meters for the reflecting surface, it is the largest in the world.
The first telescope was built on 2004 and operated for five years in standalone mode. A second MAGIC telescope (MAGIC-II), at a distance of 85 m from the first one, started taking data in July 2009. Together they integrate the MAGIC telescope stereoscopic system.
MAGIC is sensitive to cosmic gamma ray
s with energies between 50 GeV
and 30 TeV
due to its large mirror;
other ground-based gamma-ray telescopes typically observe gamma energies above 200-300 GeV. Satellite-based detectors
detect gamma-rays in the energy range from keV up to several GeV.
. The presence of such high energies indicates that the gamma-ray source is far out in the pulsar's magnetosphere
, in contradiction with many models.
MAGIC detected very high energy cosmic rays from the quasar
3c 279, which is 5 billion light years from Earth. This doubles the previous record distance from which very high energy cosmic rays have been detected. The signal indicated that the universe is more transparent than previously thought based on data from optical and infrared telescopes.
MAGIC did not observe cosmic rays resulting from dark matter decays in the dwarf galaxy
Draco. This strengthens the known constraints on dark matter models.
A much more controversial observation is an energy dependence in the speed of light of cosmic rays coming from a short burst of the blazar
Markarian 501 on July 9, 2005. Photons with energies between 1.2 and 10 TeV arrived 4 minutes after those in a band between .25 and .6 TeV. The average delay was .030±.012 seconds per GeV of energy of the photon. If the relation between the space velocity of a photon and its energy is linear, then this translates into the fractional difference in the speed of light being equal to minus the photon's energy divided by 2×1017 GeV.
Each telescope has the following specifications:
(diameter: 2.54 cm) surrounded by 180 larger photomultiplier detectors (diameter: 3.81 cm).
Physicists from over twenty institutions in Germany, Spain, Italy, Switzerland, Croatia, Finland, Poland,
Bulgaria and Armenia collaborate in using MAGIC; the largest groups are at
IACT
The IACT or Imaging Atmospheric Cherenkov Technique is the method whereby very high energy gamma-ray photons in the 50 GeV to 50 TeV range can be detected by ground based telescopes. There are currently four major ground based telescopes including CANGAROO III, MAGIC, HESS and VERITAS...
s situated at the Roque de los Muchachos Observatory
Roque de los Muchachos Observatory
Roque de los Muchachos Observatory is an astronomical observatory located in the municipality of Garafía on the island of La Palma in the Canary Islands...
on La Palma
La Palma
La Palma is the most north-westerly of the Canary Islands. La Palma has an area of 706 km2 making it the fifth largest of the seven main Canary Islands...
, one of the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
, at about 2200 m above sea level. MAGIC detects particle showers released by gamma rays, using the Cherenkov radiation
Cherenkov radiation
Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium...
, i.e., faint
light radiated by the charged particles in the showers. With a diameter of 17 meters for the reflecting surface, it is the largest in the world.
The first telescope was built on 2004 and operated for five years in standalone mode. A second MAGIC telescope (MAGIC-II), at a distance of 85 m from the first one, started taking data in July 2009. Together they integrate the MAGIC telescope stereoscopic system.
MAGIC is sensitive to cosmic gamma ray
Gamma ray
Gamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency . Gamma rays are usually naturally produced on Earth by decay of high energy states in atomic nuclei...
s with energies between 50 GeV
GEV
GEV or GeV may stand for:*GeV or gigaelectronvolt, a unit of energy equal to billion electron volts*GEV or Grid Enabled Vehicle that is fully or partially powered by the electric grid, see plug-in electric vehicle...
and 30 TeV
TEV
TEV may refer to:* TeV, or teraelectronvolt, a measure of energy* Total Enterprise Value, a financial measure* Total Economic Value, an economic measure* Tobacco etch virus, a plant pathogenic virus of the family Potyviridae....
due to its large mirror;
other ground-based gamma-ray telescopes typically observe gamma energies above 200-300 GeV. Satellite-based detectors
detect gamma-rays in the energy range from keV up to several GeV.
Aims
The goals of the telescope are to detect and study primarily photons coming from:- Accretion of black holes in Active Galactic Nuclei
- Supernova remnantSupernova remnantA supernova remnant is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way.There are two...
s, due to their interest as sources of cosmic rays. - Other galactic sources such as pulsar wind nebulae or X-ray binaries.
- Unidentified EGRETEgretAn egret is any of several herons, most of which are white or buff, and several of which develop fine plumes during the breeding season. Many egrets are members of the genera Egretta or Ardea which contain other species named as herons rather than egrets...
or Fermi sources - Gamma ray burstGamma ray burstGamma-ray bursts are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the most luminous electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several minutes, although a typical...
s - Annihilation of Dark matterDark matterIn astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...
Observations
MAGIC has found pulsed gamma-rays at energies higher than 25 GeV coming from the Crab PulsarCrab Pulsar
The Crab Pulsar is a relatively young neutron star. The star is the central star in the Crab Nebula, a remnant of the supernova SN 1054, which was widely observed on Earth in the year 1054...
. The presence of such high energies indicates that the gamma-ray source is far out in the pulsar's magnetosphere
Magnetosphere
A magnetosphere is formed when a stream of charged particles, such as the solar wind, interacts with and is deflected by the intrinsic magnetic field of a planet or similar body. Earth is surrounded by a magnetosphere, as are the other planets with intrinsic magnetic fields: Mercury, Jupiter,...
, in contradiction with many models.
MAGIC detected very high energy cosmic rays from the quasar
Quasar
A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...
3c 279, which is 5 billion light years from Earth. This doubles the previous record distance from which very high energy cosmic rays have been detected. The signal indicated that the universe is more transparent than previously thought based on data from optical and infrared telescopes.
MAGIC did not observe cosmic rays resulting from dark matter decays in the dwarf galaxy
Dwarf galaxy
A dwarf galaxy is a small galaxy composed of up to several billion stars, a small number compared to our own Milky Way's 200-400 billion stars...
Draco. This strengthens the known constraints on dark matter models.
A much more controversial observation is an energy dependence in the speed of light of cosmic rays coming from a short burst of the blazar
Blazar
A blazar is a very compact quasar associated with a presumed supermassive black hole at the center of an active, giant elliptical galaxy...
Markarian 501 on July 9, 2005. Photons with energies between 1.2 and 10 TeV arrived 4 minutes after those in a band between .25 and .6 TeV. The average delay was .030±.012 seconds per GeV of energy of the photon. If the relation between the space velocity of a photon and its energy is linear, then this translates into the fractional difference in the speed of light being equal to minus the photon's energy divided by 2×1017 GeV.
Technical specifications
- A collecting area 236 m² consisting of 50 cm x 50 cm AluminiumAluminiumAluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
individual reflectors - A lightweight carbon fibre frame
- A detector consisting of 396 separate hexagonal photomultiplier detectors in the center
(diameter: 2.54 cm) surrounded by 180 larger photomultiplier detectors (diameter: 3.81 cm).
- Data are transferred in analogue form by fibre optic cables
- Signal digitization is done via an ADC (analog-digital converter) of frequency 2 GHz
- Total weight of 40,000 kg
- Reaction time to move to any position of the sky less than 40 seconds
Collaborating Institutions
Bulgaria and Armenia collaborate in using MAGIC; the largest groups are at
- Institut de Física d'Altes Energies (IFAEIFAEThe Institute for High Energy Physics of Barcelona, Spain, is a Public Consortium between theGeneralitat de Catalunya and the...
) - Universitat Autònoma de Barcelona, SpainSpainSpain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
- Universidad Complutense MadridMadridMadrid is the capital and largest city of Spain. The population of the city is roughly 3.3 million and the entire population of the Madrid metropolitan area is calculated to be 6.271 million. It is the third largest city in the European Union, after London and Berlin, and its metropolitan...
,Spain - Max-Planck-Institute for Physics, MunichMunichMunich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
, GermanyGermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate... - Dipartimento di Fisica and INFN, University of PaduaUniversity of PaduaThe University of Padua is a premier Italian university located in the city of Padua, Italy. The University of Padua was founded in 1222 as a school of law and was one of the most prominent universities in early modern Europe. It is among the earliest universities of the world and the second...
, Italy - Tuorla ObservatoryTuorla ObservatoryTuorla Observatory is the Department of Astronomy at the University of Turku, southwest Finland. Currently it is the largest astronomical research institute in Finland...
, PiikkiöPiikkiöPiikkiö , is a former municipality of Finland. Piikkiö was consolidated with Kaarina on January 1, 2009.It is located in the province of Western Finland and is part of the Finland Proper region. The municipality had a population of 6,836 and covered an area of 90.35 km² of which...
, FinlandFinlandFinland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside... - Dipartimento di Fisica and INFN, University of SienaUniversity of SienaThe University of Siena in Siena, Tuscany is one of the oldest and first publicly funded universities in Italy. Originally called Studium Senese, the University of Siena was founded in 1240. The University has around 20,000 students, nearly half of Siena's total population of around 54,000...
, Italy - Dipatimento di Fisica and INFN, University of UdineUniversity of UdineThe University of Udine is a university in the city of Udine . It was founded in 1978 as part of the reconstruction plan of Friuli after the earthquake in 1976...
, Italy - TU Dortmund University, GermanyGermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
- University of WürzburgUniversity of WürzburgThe University of Würzburg is a university in Würzburg, Germany, founded in 1402. The university is a member of the distinguished Coimbra Group.-Name:...
, GermanyGermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate... - Institute for Particle Physics, ZürichZürichZurich is the largest city in Switzerland and the capital of the canton of Zurich. It is located in central Switzerland at the northwestern tip of Lake Zurich...
, SwitzerlandSwitzerlandSwitzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition.... - Institute for Nuclear Research and Nuclear EnergyInstitute for Nuclear Research and Nuclear EnergyInstitute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences isthe leading center for research and application of the nuclear physics in Bulgaria.The research areas include:...
, SofiaSofiaSofia is the capital and largest city of Bulgaria and the 12th largest city in the European Union with a population of 1.27 million people. It is located in western Bulgaria, at the foot of Mount Vitosha and approximately at the centre of the Balkan Peninsula.Prehistoric settlements were excavated...
, BulgariaBulgariaBulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east... - Croatian MAGIC Consortium (Institute Ruđer Bošković, ZagrebZagrebZagreb is the capital and the largest city of the Republic of Croatia. It is in the northwest of the country, along the Sava river, at the southern slopes of the Medvednica mountain. Zagreb lies at an elevation of approximately above sea level. According to the last official census, Zagreb's city...
; University of SplitUniversity of SplitThe University of Split is a university located in Split, Croatia. It was founded in 1974. and is organized in 13 faculties and 124 faculty programmes...
, SplitSplit (city)Split is a Mediterranean city on the eastern shores of the Adriatic Sea, centered around the ancient Roman Palace of the Emperor Diocletian and its wide port bay. With a population of 178,192 citizens, and a metropolitan area numbering up to 467,899, Split is by far the largest Dalmatian city and...
; University of RijekaUniversity of RijekaThe University of Rijeka is situated in the city of Rijeka with faculties also located in cities throughout the regions of Primorje, Istria and Lika....
, RijekaRijekaRijeka is the principal seaport and the third largest city in Croatia . It is located on Kvarner Bay, an inlet of the Adriatic Sea and has a population of 128,735 inhabitants...
), CroatiaCroatiaCroatia , officially the Republic of Croatia , is a unitary democratic parliamentary republic in Europe at the crossroads of the Mitteleuropa, the Balkans, and the Mediterranean. Its capital and largest city is Zagreb. The country is divided into 20 counties and the city of Zagreb. Croatia covers ...