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[8] A.Petri, Erarbeitungvon SchulmaterialienjUrdie 10.]ahrgangsstufe [11] Ch.Heimann, Einfiihrung von Elementarteilchen und ihrengrundle iiberZusammenhiinge physikalischerGrundlagenforschungmit genden Wechslwirkungenim Rahmen desKernphysikunterrrichtsin anderenForschungsgebieten(z.B. Kosmologie)und alltiiglichen der 10.KlasseeinesGymnasiums, Thesis for the second student Anwendungen (z.B. DetektorenjUrdie Medizintechnik), Thesis for teacher exam, Studienseminar K61n, August 2002,see [2] the first student teacher exam, Bonn University, June 2001, see [2] [9] G.Hacker, Grundlagender Teilchenphysik,see [2] About the author H.Ding, M.Kobel et al. Teilchenphysikin derSchule,see[2] Michael Kobel is Professor for Experimental Physics at BonnUni­ [10] D.GlaBner,Erprobungeiner Unterrichtsreihezur Elementarteilchen­ versity and active in research at CERN (OPAL, physik zur WeiterentwicklungdesLehrplansSI unter Einsatz eines ATLAS) and Fermilab (DO). Websystems,Thesis for the second student teacher exam, Studi­ enseminar Troisdorf, August 2002, see [2]

The scientific data come from the DELPHI experiment [3] at Frontline physicsfor the Large Positron Collider (LEP) at CERN. Until year 2000 LEP was producinghigh energycollisions between and positrons. During the first phase of LEP the collision energy teachers and students was 91 GeV and a single ZOparticlewas producedin the collisions (Fig. 1). During the second phase the collision energy was K.E.Johansson increased to around 210 GeV sufficient to produce WW and ZZ Department ofPhysics,Stockholm University,and Stockholm pairs. With these datavirtually all components of the Standard House ofScience,AlbaNova University Centre, Sweden Model,with the exception ofthe top quarkand the Higgs particle, can be explored-the quarks and leptons,the gluon and the elec­ troweak and strong interaction. oday's research projects can enrich physics education at We often encourage the students to lookat the Particle Adven­ Tschool and complement the traditional way physics is ture [4] to get an introduction to the world of particles. In taught. Theprojects described here explore theMilkyWay andthe order to make the students more familiar with elementary parti­ most fundamental level in the interior of matter with the aim to cles the web exercises are complemented with laboratory increase both the understanding ofandthe interestinnaturalsci­ experiments. The classical Thomson elm experimentandtheMil­ ence. Research councils and other financing bodies are starting likan experiment on the electron charge, make the students to appreciate the importance of this type ofeducationprojects for familiar with elementary particles and the manipulation ofthem the future ofscience,but a lot still remains to be done, with electric and magnetic fields.

The world of particles The structure of the Milky Way With the Hands on CERN education project [1,2] the students It is notpossible to see veryfar in the Galactic plane in the optical can "take part" in a modern particle physics experiment at the wavelength region. This is due to the absorption caused by clouds forefront ofscientific research usingscientific datatransmittedvia of dust that are distrib- Internet. The primary aim is to show particle collisions from the uted among the stars in physics frontline and to stimulate interest in science and technol­ the galaxy. This inter­ ogy. Hands on CERN complements the traditional physics stellar medium is education and confronts the students with contemporaryphysics however quite trans­ and technology at its most fundamental level. parent to radiation With high energy particle collisions it is possible to study the from the well known smallest building blocks in Nature-the quarks and the leptons. 21.1 cm line in atomic Some ofthese build up the worldwe see around us, some existed hydrogen. This radia­ naturally only at ~ebeginning oftime, the Big Bang, but are now tion makes it possible produced in high energy collisions at a few large physics labora­ to study the distribu­ tories in the world. tion ofhydrogen in our Galaxy and thereby study the spiral struc­ ;:g"~~~:~::-Iture. collision at 91 GeVat I We used a small' A Fi~.2;tudents in front ofthe r;d~io the L.IPcolHderof a I radio telescope with a telescope with which they explored the ~ MilkyWay. ZOparticle that . 2.3 m diameter para­ instantly decays into ! bolic antenna to map '--- ._J Ia quark and an ! the MilkyWay (Fig. 2). The telescope is set to detect the 21.1 cm antiquark, which give : atomic hydrogen radiation. By measuring the Doppler effect in rise to sprays of ! the received radiation one can measure the radial movements of particles that are I the spiral arms relative to us and also calculate the distance from detected in the I' the observed cloud ofhydrogen to the Galactic Centre. For these DELPHIdetector. calculations we needto know our own position andspeedrelative ._.~_ I ______•., ..•.__•.._...J to the centre of the Galaxy, but also the assumption that the tan-

no Article available at http://www.europhysicsnews.org or http://dx.doi.org/10.1051/epn:2003308europhysics news MAY/JUNE 2003 FEATURES gential velocities around the Galaxy are practically constant out­ were given to both classes to make all the students familiar with side thevery inner part of the Galaxy. This project is described in the different subjects and the fascinating connectionbetween cos­ more detail in [5]. mology and particle physics. The combination of making their The assumption of the tangential velocities being practically own measurements ofthe MilkyWaywith a small radio telescope, constant outside the central part of the galaxy has been experi­ using scientific data from high energy particle collisions and hav­ mentallyverified for several galaxies, but is nevertheless quite ing the Standard Model, the Milky Way and the Big Bang surprising. The measured rotational velocities indicate the pres­ explained byscientists created an attractive and fascinating course ence of matter in addition to the matter of the luminous stars. in contemporary science. This unknown type ofmatter, the dark matter, seems to be a very important component ofour Universe. One possibilityis that the The Houseof Science dark matter is composed of supersymmetric particles. These Until 2000 this project took place at the Science Laboratory [8] at particles could be detected in the high energy particle collisions Stockholm University, a laboratory devoted to teachers and stu­ either at the Fermilab Tevatron or the future proton collider at dents at school. This laboratory was for many years a platform CERN, the LHe. There experiments like ATLAS could very well for many projects in modern science [2,5-8]. Since 2002 the Sci­ discover the hypothetical dark matter particle of the Universe ence Laboratoryhas become the Stockholm House ofScience [9] (Fig. 3). (Fig. 4), at present devoted to astronomy, biotechnology and physics, and situated at the AlbaNova University Centre, a joint Stockholm University and Royal Institute ofTechnology centre.

Summary During the research project the students realised that they could determine some of the most fundamental quantities in the Stan­ dard Model of and learn about the structure and dynamics of our own galaxy, the Milky Way.With scientific data, the right tools and instructors the students could explore funda­ "'Fig.3: mental processes in Nature normallyonlyaccessible to scientists. Asimulated When planning future scientific projects it is essential to keep in proton-proton mind the importance of promoting the interest in science at collisionat 14TeV school and the role ofscientific outreach activities. I at the tHC collider. rAtthe collisiona I large number of References i particles are I produced and [1] Hands on CERN home page: http://hands-on-cern.physto.se 1 detected bythe [2] Hands on CERN - a Particle Physics Education Project utilising the i ATLASdetector. L . Internet, KE. Johansson and T.M. Malmgren, Physics Education 34/5(1999)286-293 [3] DELPHi home page: http://www.cem.chlDelphilWelcome.htmI Astronomyand particle physics [4] The particle adventure homepage: particleadventure.org For several years we have organised courses in astronomy and [5] Astronomy and particle physics research classes for secondary particle physics for 17 - 18 year old secondary school students. school students, KE. Johansson, Ch. Nilsson, J. Engstedt and Aa. The students either studied the differential rotation of the Milky Sandqvist, American Journal of Physics.Vol. 69, No. 5, May 2001, p. Way or the intricacies of high energy particle collisions. Plenary 577 talks by scientists in astronomy, cosmology and particle physics [6] Stockholm Science Laboratory for Schools, KE. Johansson and Ch. Nilsson, Physics Education 34/6(1999)345 [7] Experiments in Modern Physics for the General Public, KE.Johans­ son and Ch. Nilsson, Physics Education 35/4(2000)256 [8] The physics of'Copenhagen' for students and the General Public, 1. Bergstrom, KE. Johansson and Ch. Nilsson, Physics Education 36/5 (2001)388 [9] The House of Science homepage (at present in Swedish): www.houseofscience.org

About the author Erik Johansson is Professor in particle physics atStockholm Uni­ versity and Director of Stockholm House of Science, AlbaNova University Centre.

.. Fig. 4:The Stockholm Iiouse of Science on the campus of the Alb~ovaUniversityCentre. europhysics news MAY/jUNE 2003 111