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1) Mahantesh L Chikkadesai 2) Ramakrishna R Pujari [email protected] [email protected] Mobile no: +919480780580 Mobile no: +917411812551 Phy 009 Sub atomic particles and Phy 009 Sub atomic particles and developments in cern developments in cern Electrical and Electronics Electrical and Electronics KLS’s Vishwanathrao deshpande rural KLS’s Vishwanathrao deshpande rural institute of technology institute of technology Haliyal, Uttar Kannada Haliyal, Uttar Kannada SUB ATOMIC PARTICLES AND DEVELOPMENTS IN CERN Abstract-This paper reviews past and present cosmic rays. Anderson discovered their existence; developments of sub atomic particles in CERN. It High-energy subato mic particles in the form gives the information of sub atomic particles and of cosmic rays continually rain down on the Earth’s deals with basic concepts of particle physics, atmosphere from outer space. classification and characteristics of them. Sub atomic More-unusual subatomic particles —such as particles also called elementary particle, any of various self-contained units of matter or energy that the positron, the antimatter counterpart of the are the fundamental constituents of all matter. All of electron—have been detected and characterized the known matter in the universe today is made up of in cosmic-ray interactions in the Earth’s elementary particles (quarks and leptons), held atmosphere. together by fundamental forces which are Quarks and electrons are some of the elementary represente d by the exchange of particles known as particles we study at CERN and in other gauge bosons. Standard model is the theory that laboratories. But physicists have found more of describes the role of these fundamental particles and these elementary particles in various experiments. interactions between them, this is briefly reviewed Our best understanding of how these particles and and this standard model with its salient features described. T o understand how the universe evolved three of the forces are related to each other is we really need to understand the behaviour of encapsulated in the Standard Model of particle elementary particles: the quarks, leptons and gauge physics. Developed in the early 1970s, it has bosons. Since from 1954 several important successfully explained almost all experimental achievements in particle physics have been made results and precisely predicted a wide variety of during experiments at CERN, th ey have discovered phenomena. Over time and through many many particles. In this paper, several results of those experiments, the Standard Model has become experiments are described. established as a well-tested physics theory. Keywords: Elementary particles, Large Hadron Collider, fundamental interactions, gauge boson, Fermi lab. I. INTRODUCTION The theories and discoveries of tho usands of physicists since the 1930s have resulted in a remarkable insight into the fundamental structure of matter: everything in the universe is found to be made from a few basic building blocks called fundamental particles. Small particles in the hierarchy of the universe were discovered and researched: these are commonly molecules , that are constructed of atoms , that in turn consist of subatomic particles, Thomson ha d discovered the first subatomic particle. A subatomic particle is a particle smaller than an atom: it may be elementary or composite. These particles include atomic constituents such as electrons, protons, and neutrons (protons and neutrons are actually c omposite particles, made up of quarks), as well as other particles such as photons and neutrinos which are produced copiously in the sun. The concept of spin is now recognized as an intrinsic property of all subatomic particles. However, most of the particles that have been discovered and studied are not encountered under normal earth conditions; they are produced in Fig.1 evolution of sub atomic particles II. CERN • The ALPHA experiment is a successor of an earlier antimatter experiment. The European Organization for Nuclear Research e) AMS: known as CERN, whose purpose is to operate the • The Alpha Magnetic Spectrometer looks world's largest particle physics laboratory. for dark matter, antimatter and missing Established in 29 September 1954, the organization matter from a module on the International is based in the northwest suburbs of Geneva on the Space Station. Franco–Swiss border, and has twenty European • The Alpha Magnetic Spectrometer (AMS- member states. 02) is a particle-physics detector that looks CERN's main function is to provide the particle for dark matter, antimatter and missing accelerators and other infrastructure needed for matter from a module attached to the high-energy physics research. It is also the outside of the International Space Station birthplace of the World Wide Web. (ISS). It also performs precision measurements of cosmic rays. A. Experiments at CERN: f) ASACUSA: a) ACE: • The Atomic Spectroscopy And Collisions • The Antiproton Cell Experiment (ACE) Using Slow Antiprotons (ASACUSA) started in 2003. It aims to assess fully the experiment studies the fundamental effectiveness and suitability of antiprotons symmetries between matter and antimatter for cancer therapy. • by precision spectroscopy of atoms ACE brings together an international team containing an antiproton (the antimatter of physicists, biologists and medics to equivalent of the proton). The experiments study the biological effects of antiprotons. focused in particular on hybrid atoms • ACE is an excellent example of how (antiprotonic helium), ASACUSA research in particle physics can bring compares matter and antimatter using innovative solutions with potential atoms of antiprotonic helium and medical benefits. antihydrogen, and studies the properties of b) AEGIS: matter-antimatter collisions. • The primary scientific goal of the Anti g) ATLAS: hydrogen Experiment: Gravity, • ATLAS is one of two general-purpose Interferometry, Spectroscopy (AEGIS) is detectors at the Large Hadron Collider the direct measurement of the Earth's (LHC). It investigates a wide range of gravitational acceleration, on physics, from the search for the Higgs antihydrogen. boson to extra dimensions and particles • AEGIS uses a beam of antiprotons from that could make up matter. From a cavern the Antiproton Decelerator to measure the 100 metres below a small Swiss village, value of Earth’s gravitational acceleration. the 7000-tonne ATLAS detector is The AEGIS experiment will represent the probing for fundamental particles. first direct measurement of a gravitational h) ATRAP: effect on an antimatter system. • ATRAP compares hydrogen atoms with their antimatter equivalents - antihydrogen atoms. The Antihydrogen trap (ATRAP) is an experiment to compare hydrogen atoms c) ALICE: with their antimatter equivalents – • ALICE detects quark-gluon plasma, a antihydrogen atoms. In 2002, ATRAP state of matter thought to have formed just provided the first glimpse inside after the big bang. antihydrogen atoms after researchers • ALICE (A Large Ion Collider Experiment) successfully created and measured a large is a heavy-ion detector on the Large number of them. ATRAP was the first Hadron Collider (LHC) ring. It is designed experiment to use cold positrons to cool to study the physics of strongly interacting antiprotons. matter at extreme energy densities, where i) AWAKE: a phase of matter called quark-gluon • AWAKE explores the use of plasma to plasma forms. accelerate particles to high energies over d) ALPHA: short distances. • ALPHA makes, captures and studies j) CAST: atoms of antihydrogen and compares them • The CERN Axion Solar Telescope with hydrogen atoms. (CAST) is an experiment to search for hypothetical particles called "axions". These have been proposed by some theoretical physicists to explain why and neutrons that form the nuclei of there is a subtle difference between matter ordinary atoms. and antimatter in processes involving the • A collaboration of CERN physicists are weak force, but not the strong force. If studying the decay of unstable “pionium axions exist, they could be found in the atoms” to gain insight into the strong centre of the Sun and they could also force. make up invisible dark matter. o) ISOLDE: • Hypothetical particles called axions could • ISOLDE studies the properties of atomic explain differences between matter and nuclei, with further applications in antimatter - and we may find them at the fundamental studies, astrophysics, centre of the Sun. material and life sciences The Isotope k) CLOUD: mass Separator On-Line facility • The Cosmics Leaving Outdoor Droplets (ISOLDE) is a unique source of low- (CLOUD) experiment uses a special cloud energy beams of radioactive nuclides, chamber to study the possible link those with too many or too few neutrons between galactic cosmic rays and cloud to be stable. It permits the study of the formation. Based at the Proton vast territory of atomic nuclei, including Synchrotron (PS) at CERN, this is the first the most exotic species. time a high-energy physics accelerator has p) LHCb: been used to study atmospheric and • The LHCb experiment will shed light on climate science. The results should why we live in a universe that appears to contribute much to our fundamental be composed almost entirely of matter, but understanding of aerosols and clouds, and no antimatter. their affect on climate. q) LHCf: • Could there be a link between galactic • The LHCf experiment uses particles cosmic rays and cloud formation? An thrown forward by LHC collisions
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