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Synchrotron Radiationradiation ASTRID2: the new Danish light source SynchrotronSynchrotron RadiationRadiation The state-of-the art synchrotron light source, ASTRID2, SynchrotronSynchrotron radiationradiation isis thethe namename givengiven toto thethe electromagneticelectromagnetic radiationradiation whichwhich isis emittedemitted byby relativisticrelativistic electronselectrons beingbeing deflecteddeflected byby aa magneticmagnetic field.field. will be used for research within medicine, molecular SynchrotronSynchrotron radiationradiation occursoccurs naturallynaturally inin spacespace wherewhere relativisticrelativistic electronselectrons spiralspiral HST and cell biology, nanotechnology, new materials throughthrough magneticmagnetic fields,fields, anan exampleexample ofof thisthis cancan bebe seenseen inin thethe CrabCrab NebulaNebula (picture(picture toto thethe right).right). and atomic and molecular physics. This world SynchrotronSynchrotron radiationradiation cancan alsoalso bebe producedproduced artificiallyartificially class infrastructure will provide near laser-like usingusing aa synchrotronsynchrotron storagestorage ringring suchsuch asas ASTRID2.ASTRID2. WhenWhen electronselectrons inin thethe ringring areare acceleratedaccelerated toto speedsspeeds closeclose toto N beam quality, with tuneable wavelengths thatthat ofof light,light, radiationradiation isis emittedemitted withinwithin aa narrownarrow conecone inin from the ultraviolet to the X-ray. thethe directiondirection ofof motion.motion. ThereThere areare 1616 bunchesbunches ofof electronselectrons inin ASTRID2.ASTRID2. 9.5 ns TheThe lightlight fromfrom oneone bunchbunch ofof electronselectrons appearsappears ASTRID2 0.1 ns asas aa flashflash ofof radiationradiation withwith onlyonly 9.59.5 nsns betweenbetween Time eacheach flashflash ofof light,light, soso fastfast thatthat toto thethe humanhuman eyeeye thethe lightlight emittedemitted appearsappears toto bebe constant.constant. TheThe polarisationpolarisation ofof thethe radiationradiation emittedemitted fromfrom aa bendingbending magnetmagnet isis linearlinear inin thethe planeplane ofof thethe electronelectron orbit.orbit. AboveAbove andand belowbelow thethe planeplane thethe radiationradiation isis ellipticallyelliptically polarised.polarised. TheThe degreedegree ofof polarisationpolarisation isis dependentdependent onon bothboth thethe viewingviewing angleangle andand thethe wavelengthwavelength ofof thethe radiation.radiation. BrightnessBrightness ofof synchrotronsynchrotron radiationradiation fromfrom ASTRID2ASTRID2 Undulator ASTRID2 2T, 6 pole ASTRID wiggler TheThe mainmain advantagesadvantages ofof synchrotronsynchrotron radiationradiation fromfrom aa storagestorage ringring ASTRID ASTRID2 overover radiationradiation fromfrom conventionalconventional sourcessources are:are: TheThe spectrumspectrum ofof lightlight isis continuouscontinuous fromfrom thethe infraredinfrared regionregion toto softsoft ASTRID2 XX--rays.rays. History ASTRID AA highhigh levellevel ofof polarisationpolarisation ofof thethe lightlight (linear(linear oror elliptical)elliptical) .. Bending Magnet 1928: Aarhus University founded. Solar TheThe brightnessbrightness isis manymany ordersorders ofof magnitudemagnitude timestimes higherhigher thanthan 1933: The first Physics Department opens at Aarhus University. Radiation conventionalconventional sources.sources. 1938: First large accelerator is built, the “high voltage platform”. TheThe beambeam hashas aa timetime structure.structure. 1974: Physics Department moves into the current buildings. 1991: Inauguration of the ASTRID accelerator. TheThe ElectromagneticElectromagnetic SpectrumSpectrum 2009-2013: ASTRID2 is built; inauguration in 2012. TheThe electromagneticelectromagnetic spectrumspectrum isis thethe entireentire rangerange ofof wavelengthswavelengths (or(or frequencies)frequencies) ofof electromagneticelectromagnetic radiation,radiation, fromfrom thethe longestlongest radioradio waveswaves used,used, forfor example,example, toto detectdetect aircraft,aircraft, toto gammagamma raysrays whichwhich areare usedused inin positronpositron emissionemission tomographytomography (PET)(PET) andand cancercancer radiationradiation therapy.therapy. VisibleVisible lightlight isis onlyonly aa smallsmall partpart ofof thethe spectrum.spectrum. ASTRID Funding Commissioned in 1991 as a storage ring uniquely for both ions and electrons, 37 Mkr The National Programme for Research Infrastructures, the Danish The region of the electromagnetic spectrum detected by the human eye is called visible light ASTRID has operated as a dedicated synchrotron light source since 2006. Agency for Science, Technology and Innovation. The new facility will use ASTRID as a full energy injector for ASTRID2, topping up ~10 Mkr The Lundbeck Foundation, The Carlsberg Foundation, the current to create an unlimited beam lifetime for the ASTRID2 source. The Danish Council for Independent Research | Natural Sciences. 106 107 108 109 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 Many of the beam lines currently on ASTRID will be transferred to the new ring with 12 Mkr Financing from Aarhus University. minor changes in order to take full advantage of the new brilliant light source. A ~20 Mkr Building work, Aarhus University brand new beam line for Atomic, Molecular and Optical physics has also been ~100 Mkr The existing ASTRID accelerator. 102 101 1 10-1 10-2 10-3 10-4 10-5 10-6 10-7 10-8 10-9 10-10 10-11 10-12 10-13 funded. International Research Design Technology Synchrotron radiation is one of the The long-standing accelerator expertise at Aarhus University has meant that all best tools of today for investigating aspects of the brilliant new light source, ASTRID2, have been designed and and understanding nature at the constructed by the staff at the Department of Physics microscopic level. The brilliance of and Astronomy. Likewise the complex and the light from ASTRID2 will allow new challenging task to build novel experimental BeamBeam lineslines science to be performed in which we instrumentation for beam lines and TheThe instrumentationinstrumentation requiredrequired toto guideguide photonsphotons fromfrom thethe synchrotronsynchrotron storagestorage ringring toto anan experimentalexperimental endend stationstation can, for example, examine drug experimental stations is being met isis calledcalled aa beambeam lineline.. TypicallyTypically consistingconsisting ofof mirrorsmirrors andand aa gratinggrating soso thatthat aa specificspecific energyenergy ofof photonsphotons cancan bebe action, probe new means of locally. selected,selected, aa beambeam lineline focusesfocuses thethe lightlight ontoonto oror throughthrough aa samplesample underunder investigation.investigation. fabricating electronics and examine the properties of exotic metals, nanowires and biological molecules. The facility serves a wide community of scientists from both Denmark and internationally, acting as a powerful catalyst for EU Development of the ASTRID2 machine is based on technological innovations and worldwide and forms a solid basis for Denmark’s knowledge and knowhow in advanced collaboration. accelerators, especially relevant for particle beam cancer therapy. .
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