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BEAM PHYSICS INTRODUCTION L.Gatignon / AB-ATB-EA • Optics principles, optics drawings • Momentum definition • Collimation • Particle production • Passage of particles through material • Targets, converters and absorbers • Electron, hadron and muon beams • Beam instrumentation and their underlying ‘physics’ • The H6 beam line Qualitative rather than quantitative !!! Summer 2007 Summer Student Workshop Layout 8 beams running at the same time 15 test facilities 5 installed experiments 6.3 km of beam lines 4 Experimental halls Nevertheless, as the West Area beams were short and simple, we will sometimes use one of them as an example. Summer 2007 Summer Student Workshop Summer 2007 Summer Student Workshop PARTICLES IN A MAGNETIC FIELD F In a magnetic field, the force is perpendicular to the velocity of the particle and to the field: F=qvxB B In a uniform magnetic field the deflection of a particle depends on the product of field B and length L of the magnet: q [rad] = 0.3 q BL [Tm] / p [GeV/c] BL [Tm] For a given magnet, the length is fixed but the field B (and hence the BL) can be controlled via its current I. In the experimental areas the current is constant over the spill ! Summer 2007 Summer Student Workshop Io I [A] BENDs and TRIMs q = 0.3 BL p A dipole acts like a prism: 400 GeV 350 GeV 300 GeV 250 GeV 200 GeV Together with a collimator, a dipole can be used to define a momentum p The Dp depends on the gap width Bends have a nominal deflection of the beam axis, Trims are correctors only (nominal field is 0). Big spectrometer magnets in the experiments are also called bends! Summer 2007 Summer Student Workshop QUADRUPOLES N S S N B ~ field line density Focus in Horizontal plane Defocus in Vertical plane B-field lines or vice versa N S S N Magnetic force B, F, Gradient Like an optical lense ! Distance from axis Summer 2007 f Summer Student Workshop Basic optics principles To focus in both planes one needs at least two quadrupoles (doublet) but horizontal and vertical magnification are rather different and there are no degrees of freedom (apart from H-V flip) A triplet can also focus in both planes, but also: Mx and My can be equal Mx and My can be tuned In the optics diagrams shown, the lines can be understood in two ways: • Trajectories of specific particles (with e.g. Xo = 0 or X’o = 0) • Drawings of transfer matrix elements Summer 2007 Summer Student Workshop Summer 2007 Summer Student Workshop Summer 2007 Summer Student Workshop Matrix elements Xo X1 Some optics elements Xo’ X1’ Transfer matrix R X1 X1’ = R11 R12 Xo R21 R22 Xo’ R11 Xo + R12 Xo’ = R21 Xo + R22 Xo’ 1 L e.g. : Drift space L: 0 1 1 Quadrupole: 0 -1/f 1 (f = focal length) Summer 2007 Summer Student Workshop Generalisation to real systems The matrix of a system is the product of the individual matrices: Q2 Q1 Horiz But also include: Y-coordinates Momentum p Vert 1 L3 0 1 1 0 1/ f2 1 1 L2 0 1 1 0 1 - /f1 1 1 L1 0 1 Xo Xo’ Doublet optics X X’ Y Y’ L 6x6 matrices ! Dp/p TRANSPORT RUN25/02/03 POSITION TYPE METERS STRENGTH * H O R I Z O N T A L * V E R T I C A L * D I S P E R S I O N T*M,T/M*M * R11 R12 R21 R22 * R33 R34 R43 R44 * R16 R26 R36 R46 T/M**2*M * MM/MM MM/MR MR/MM MR/MR * MM/MM MM/MR MR/MM MR/MR * MM/PC MR/PC MM/PC MR/PC ************************************************************************************************************************************ 0.000 3 TARGET * 1.000 0.000 0.000 1.000 * 1.000 0.000 0.000 1.000 * 0.000 0.000 0.000 0.000 9.000 3 * 1.000 9.000 0.000 1.000 * 1.000 9.000 0.000 1.000 * 0.000 0.000 0.000 0.000 11.000 5 Q1 61.9865 * 0.820 9.257 -0.175 -0.751 * 1.192 12.851 0.198 2.970 * 0.000 0.000 0.000 0.000 19.000 3 * -0.576 3.250 -0.175 -0.751 * 2.772 36.609 0.198 2.970 * 0.000 0.000 0.000 0.000 21.000 5 Q2 -61.9865 * -1.058 2.276 -0.322 -0.253 * 2.644 35.592 -0.322 -3.955 * 0.000 0.000 0.000 0.000 30.000 3 * -3.955 0.000 -0.322 -0.253 * -0.253 0.000 -0.322 -3.955 * 0.000 0.000 0.000 0.000 30.000 3 FOCUS * -3.955 0.000 -0.322 -0.253 * -0.253 0.000 -0.322 -3.955 * 0.000 0.000 0.000 0.000 Summer 2007 Summer Student Workshop DISPERSION Dispersion is necessary in secondary (tertiary) beams to define the momentum: Momentum slit However, for good beam performance you must: • optimise momentum resolution focus at momentum slit • get rid of dispersion at the end of the beam line field lense Focus at momentum slit B1 Field lense B2 Either B1 or B2 is the momentum reference Summer 2007 Summer Student Workshop Optics – general observations • Beams are normally small in a focus Except when the dispersion is very large at the focus or in m beam • Experimental targets are normally in a focus They want a small spot Less sensitive to changes of angle at primary target •A Trim (or Bend) in a focus will NOT affect the position of the beam at the next focus (e.g. at the experiment) But it will affect the angle and it may improve transmission. Trims in a parallel section have the maximum steering effect. • Material on the beam has less effect if in a focus Even if scattered, it particle come back to the same point Summer 2007 Summer Student Workshop Optics calculations Optics drawings can be interpreted as 1. matrix element representations 2. trajectories of specific particles For optics design the matrix element approach must be used The TRANSPORT program calculates transfer matrix elements and adjusts the individual parameters (f, L, etcetera) to fit the optics requirements. The result is a TABLE with transfer matrix elements and an optics drawing. The effect of aperture limitations (e.g. collimators) and material on the beam can only be evaluated in the trajectory approach. The DECAY TURTLE program is used to track individual particles though the beam line and to provide plots of particle properties, such as positions, angles and momenta, as well as a table of particle losses along the beam. Summer 2007 Summer Student Workshop TRANSPORT TABLE: X5 DEVELOPMENT FOR 250 GEV VERSION - LGA 090490 TRANSPORT RUN 4/09/02 POSITION TYPE METERS STRENGTH * H O R I Z O N T A L * V E R T I C A L * D I S P E R S I O N T*M,T/M*M * R11 R12 R21 R22 * R33 R34 R43 R44 * R16 R26 R36 R46 T/M**2*M * MM/MM MM/MR MR/MM MR/MR * MM/MM MM/MR MR/MM MR/MR * MM/PC MR/PC MM/PC MR/PC ************************************************************************************************************************************ 0.000 3 X5TG * 1.000 0.000 0.000 1.000 * 1.000 0.000 0.000 1.000 * 0.000 0.000 0.000 0.000 14.500 3 * 1.000 14.500 0.000 1.000 * 1.000 14.500 0.000 1.000 * 0.000 0.000 0.000 0.000 17.448 5 Q1 23.4981 * 0.915 16.127 -0.057 0.088 * 1.088 18.807 0.060 1.964 * 0.000 0.000 0.000 0.000 18.300 3 * 0.866 16.202 -0.057 0.088 * 1.139 20.480 0.060 1.964 * 0.000 0.000 0.000 0.000 21.248 5 Q2 23.4981 * 0.629 15.072 -0.102 -0.844 * 1.423 28.235 0.135 3.373 * 0.000 0.000 0.000 0.000 26.946 3 * 0.050 10.265 -0.102 -0.844 * 2.189 47.457 0.135 3.373 * 0.000 0.000 0.000 0.000 29.894 5 Q3 -16.4899 * -0.252 8.357 -0.106 -0.464 * 2.446 54.349 0.038 1.255 * 0.000 0.000 0.000 0.000 30.746 3 * -0.342 7.962 -0.106 -0.464 * 2.479 55.418 0.038 1.255 * 0.000 0.000 0.000 0.000 33.694 5 Q4 -16.4899 * -0.681 7.055 -0.127 -0.158 * 2.440 55.712 -0.064 -1.058 * 0.000 0.000 0.000 0.000 38.496 3 * -1.289 6.298 -0.127 -0.158 * 2.131 50.633 -0.064 -1.058 * 0.000 0.000 0.000 0.000 41.496 4 B1 2.3679 * -1.668 5.825 -0.127 -0.158 * 1.938 47.460 -0.064 -1.058 * 0.089 0.059 0.000 0.000 42.196 3 * -1.757 5.715 -0.127 -0.158 * 1.893 46.720 -0.064 -1.058 * 0.130 0.059 0.000 0.000 45.196 4 B1 2.3679 * -2.136 5.241 -0.126 -0.158 * 1.701 43.547 -0.064 -1.058 * 0.396 0.118 0.000 0.000 45.896 3 * -2.225 5.131 -0.126 -0.158 * 1.656 42.807 -0.064 -1.058 * 0.479 0.118 0.000 0.000 48.896 4 B1 2.3679 * -2.604 4.658 -0.126 -0.158 * 1.463 39.634 -0.064 -1.058 * 0.923 0.177 0.000 0.000 49.596 3 * -2.693 4.547 -0.126 -0.158 * 1.418 38.894 -0.064 -1.058 * 1.047 0.177 0.000 0.000 52.596 4 B1 2.3679 * -3.072 4.074 -0.126 -0.158 * 1.225 35.721 -0.064 -1.058 * 1.668 0.237 0.000 0.000 53.296 3 * -3.161 3.963 -0.126 -0.158 * 1.180 34.981 -0.064 -1.058 * 1.834 0.237 0.000 0.000 56.296 4 B1 2.3679 * -3.540 3.489 -0.126 -0.158 * 0.987 31.808 -0.064 -1.058 * 2.632 0.296 0.000 0.000 56.996 3 * -3.628 3.379 -0.126 -0.158 * 0.942 31.068 -0.064 -1.058 * 2.839 0.296 0.000 0.000 59.996 4 B1 2.3679 * -4.007 2.905 -0.126 -0.158 * 0.749 27.895 -0.064 -1.058 * 3.815 0.355 0.000 0.000 67.771 3 * -4.990 1.677 -0.126 -0.158 * 0.250 19.672 -0.064 -1.058 * 6.574 0.355 0.000 0.000 70.719 5 Q5 21.1651 * -4.969 1.094 0.140 -0.232 * 0.075 18.026 -0.056 -0.074 * 7.087 -0.011 0.000 0.000 71.201 3 * -4.901 0.982 0.140 -0.232 * 0.048 17.990 -0.056 -0.074 * 7.082 -0.011 0.000 0.000 74.149 5 Q5 21.1651 * -4.121 0.240 0.382 -0.265 * -0.117 19.188 -0.058 0.897 * 6.505 -0.375 0.000 0.000 75.055 3 * -3.775 0.000 0.382 -0.265 * -0.169 20.000 -0.058 0.897 * 6.166 -0.375 0.000 0.000 75.055 3 C1C2 * -3.775 0.000 0.382 -0.265 * -0.169 20.000 -0.058 0.897 * 6.166 -0.375 0.000 0.000 83.357 3 * -0.603 -2.199 0.382 -0.265 * -0.647 27.444 -0.058 0.897 * 3.052 -0.375 0.000 0.000 88.357 4 B2 5.0134 * 1.308 -3.524 0.382 -0.265 * -0.935 31.927 -0.058 0.897 * 1.489 -0.250 0.000 0.000 89.017 3 * 1.560 -3.699 0.382 -0.265 * -0.973 32.519 -0.058 0.897 * 1.324 -0.250 0.000 0.000 94.017 4 B3 5.0134 * 3.470 -5.023 0.382 -0.265 * -1.261 37.002 -0.058 0.897 * 0.388 -0.125 0.000 0.000 94.677 3 * 3.722 -5.197 0.382 -0.265 * -1.299 37.594 -0.058 0.897 * 0.306 -0.125 0.000 0.000 99.677 4 B2 5.0134 * 5.632 -6.520 0.382 -0.265 * -1.586 42.077 -0.058 0.897 * -0.004 0.001 0.000 0.000 107.457 3 * 8.602 -8.578 0.382 -0.265 * -2.034 49.053 -0.058 0.897 * 0.000 0.001 0.000 0.000 110.405 5 Q6 -27.6117 * 10.656 -10.272 1.035 -0.904 * -1.995 46.704 0.084 -2.463 * 0.002 0.001 0.000 0.000 117.905 3 * 18.419 -17.051 1.035 -0.904 * -1.366 28.230 0.084 -2.463 * 0.007 0.001 0.000 0.000 120.853 5 Q7 24.0089 * 19.777 -18.152 -0.128 0.168 * -1.235 23.285 0.007 -0.941 * 0.008 0.000 0.000 0.000 121.324 3 * 19.717 -18.073 -0.128 0.168 * -1.231 22.842 0.007 -0.941 * 0.008 0.000 0.000 0.000 122.124 5 Q7 6.5153 * 19.487 -17.822 -0.447 0.460 * -1.234 22.237 -0.013 -0.574 * 0.008 0.000 0.000 0.000 160.853 3 * 2.173 0.000 -0.447 0.460 * -1.742 0.000 -0.013 -0.574 * 0.011 0.000 0.000 0.000 Summer 2007 Summer Student Workshop Summer 2007 Summer Student Workshop COLLIMATION • Collimation is as important for beam quality as optics • Optics and collimation are very much correlated Basically we consider 4 different types of collimators: 1. 2. 3. 4. Dump collimators (TAX) Momentum slits Acceptance collimators Cleaning collimators Sometimes individual collimators can share several functions Summer 2007 Summer Student Workshop 1. Dump collimators (TAX) TAX stands for Target Attenuator eXperimental areas A TAX serves to stop the primary beam (e.g. in case of access) or to define the beam acceptance or limit its rate (by attenuation) primary beam Target Acceptance defined by TAX A TAX is a 1.6 m long water-cooled table with Cu, Al and Fe blocks This table is motorised in the vertical plane Through those blocks some holes of different diameters are drilled Some holes contain 40 – 120 cm of Beryllium (for attenuation) One position (+ 140 mm) is fully plugged (DUMP) The range of the movement is interlocked (EA safe – Chain 9) TAX are also safety elements in the Access system Summer 2007 Summer Student Workshop 2. Momentum slit Normally located at a dispersive focus. The center of the gap should be at the nominal beam axis. The aperture is proportional to the accepted momentum band, The rate is normally also proportional to the gap. However, the DP/p cannot be smaller than the intrinsic resolution. Hence the need (in general) to have a rather sharp focus. 3. Acceptance collimator Located where the beam is large (ideally even parallel), Allows to define the angular aperture of the beam, Affects therefore the rate as well, however non-linearly. 4. Cleaning collimator A repetition of an earlier (acceptance) collimator. Cleans up particles scattered on the edge of the earlier collimator Summer 2007 Summer Student Workshop Intensities in a secondary beam Secondary primary proton beam x . 1012 ppp beam < 108 ppp Primary Target x . 64 kJ Summer 2007 Tertiary beam < 104 ppp Secondary Target few J Summer Student Workshop mJ WHAT HAPPENS TO PARTICLES IN MATTER ? Hadronic showers (p, n, K, p, L, …) Typical length scale: Lint po p, p m Electromagnetic showers (g, e+, e-) Typical length scale: Xo Muons are produced mainly via pion decay. They traverse many metres of material with minimum energy loss: 2 GeV / m Iron) Summer 2007 Material Xo Lint Xo/Lint Beryllium Copper Lead 35.3 cm 1.50 cm 0.56 cm 40.7 cm 15.0 cm 17.1 cm 0.87 0.10 0.03 Summer Student Workshop Primary targets Primary beam Secondary beam 400 GeV protons Typically p, e Typically you want to produce: • Protons (target serves as attenuator) • Pions, produced in hadronic interactions Need about 1 Lint • Electrons, produced in electromagnetic processes The more Xo, the lower the e+ energy coming out Need about 1 Xo • As few muons as possible Put shielding (TAX) before pions decay into muons Longer target: • More production • More re-absorption Optimum around 40-50 cm etarget 0.4 0.2 Target material with large Xo/Lint: Beryllium Summer 2007 Summer Student Workshop Ltgt 0 0 20 40 60 80 100 cm Secondary beam composition at 0 mrad production angle The secondary particle composition depends on the beam momentum and on the production angle. In the plots on the right hand side the production angle has been fixed at 0 milliradians. These plots are calculated using the partprod applet on the Web: cern.ch/gatignon/partprod.html The curves on the right hand side do not take into account electrons. At -120 GeV/c electrons are about 6-7% of the beam flux, assuming a primary proton momentum of 400 GeV/c. They are valid for thin Be targets. Summer 2007 Summer Student Workshop Particle production formula Hadron beam intensity calculations are based on a parametrisation of data taken by the NA20 experiment, many years ago. A simple formula gives absolute intensities for protons, pions and kaons. These are expressed as particles per interacting proton and per steradian. Note that normally the beam acceptance is of the order of microsteradians: Acceptance = p qx qy Where qx,y are the half openings of the beam acceptance in radians. A web interface (applet) is available to calculate the rates: http://cern.ch/gatignon/partprod.html These calculations are quite precise for 60 GeV/c and above. Summer 2007 Summer Student Workshop SECONDARY TARGETS Example: X7 tertiary beam (now dismounted) Secondary beam X7 beam -120 GeV 90% p-, 10% e1) 4 mm thick Lead target 5 – 100 GeV/c, e or p 1 Xo , 0 Lint Almost all pions fly through at -120 GeV/c, Electrons loose energy due to Bremsstrahlung Many low-energy electrons are produced 2) 40 cm Copper target Pure electrons 30 Xo , 3 Lint Electrons are essentially absorbed Pions have time to interact and produce low-energy pions 3) 40 cm Beryllium target 1 Xo , 1 Lint Produces both pions and electrons Summer 2007 Hadrons Summer Student Workshop Mixed beam OTHER WAYS TO PRODUCE ELECTRONS 1. Electron Wobbling g Target p B3T Large I e- Lead converter In the target, charged and neutrals are produced. Sweep away all the charged by a strong field. The photons fly though and convert in a lead sheet. The produce electron-positron pairs. Either electrons or positrons can be transported by the beam line. 2. Use synchrotron radiation E-loss in H3 (GeV) 30 At high energy, electrons loose energy along the beam (like in LEP), whereas pions do not due to their higher mass. Therefore they follow increasingly different trajectories, until the pions (or electrons) can be stopped by well chosen collimation. The currents must take the energy loss into account. Summer 2007 Summer Student Workshop 20 10 100 200 300 Eo Muons from pion decay •Pion decay in p center of mass: mp2 – mm2 p* = = 30 MeV/c 2 mp E* = mp2 mm2 + 2 mp m (p*, E*) q* n = 110 MeV/c m • Boost to laboratory frame: Em = gp (E* + bp p* cos q*) with bp 1 • Limiting cases: cos q = +1 → Emax = 1.0 Ep cos q = -1 → Emin = 0.57 Ep Summer 2007 Summer Student Workshop 0.57 < Em / Ep < 1 SCINTILLATORS Scintllator Scintillating material (some plastics) produce light when traversed by charged particles. Light is transmitted to photomultiplier by light guide. In the photomultiplier the light is converted into an electrical pulse. After discrimination these pulses are counted by scalers and the count rates are transmitted to the control system. HV Light guide PM SIGNAL Individual particles are counted as a function of beam conditions. Useful for monitoring, beam tuning and as a timing signal (T0) for more complicated detectors (XCET, Cedar, XDWC). Strobing of complicated detectors: Cerenkov counters XCET XTRI XDWC's XTRI XTRI Limited to ≈ 107 particles per second. Examples: Summer 2007 XTRI,XTRS FISCS Spectrometers X DW C's BEND XTRI Big scintillators to count full beam Narrow, mobile scintillators to scan through beam Summer Student Workshop WIRE CHAMBERS 0V Gas Charged particles ionise the gas. The electrons drift to the anode wire, where the field increases, due the extremely small radius → Gas amplification. An electrical pulse is produced, discriminated and sent to DAQ. The positive ions drift slowly to the cathode plane → slow detectors. 2-3 kV Ø-20 mm 0V d Due to well chosen geometry each wire corresponds to a cell, electrically insulated from its neighbour. The wire hit gives an indication about the position of the particle, resolution ±0.5 d. Examples: Wire chamber XWCA XWCD XDWC SPECTRO Summer 2007 Each hit gives x±d/2 for the particle measured, limited to ≈ 107 particles per burst. Integrate charge deposited on each wire over the burst. Depends on HV! No information about individual particles, but profiles for 104 to 1010 ppp. The time between the signal on the wire and the time of particle passage (XTRI, XTRS) measures the distance between particle and wire. Improves the resolution to about 100 mm. Rates ≤ 107 ppp. Idem but use a simple delay line for readout. Easy to use, but ≤ 104 - 105 ppp Measure 2 positions before and 2 after a bend. Obtain q for the particle. As the BL of the bend is known, the momentum of each individual particle can be measured to a few permille Summer Student Workshop Mirror Threshold Cerenkov counters light In a medium (e.g. He or N2 gas): particle: v/c = p/√(p2+m2) light: Ø Gas v/c = 1/n If a charged particle goes faster than light in a medium, it emits Cerenkov light in a cone with half-opening angle f: f2 = 2kP - m2 /p2 HV PM Signal where k depends on the gas, P=pressure. Light is thus only emitted when Ø2 ≥ 0 !!! The # g’s ~ Ø2 and increases from 0 at threshold to ≈ 100% at very high pressures. Efficiency p p e P (bar) By selecting the right operating pressure, one type of particle has good efficiency and the other gives no signal. By making a coincidence with scintillator signals, particle identification can be made. XCET counters are better at low momenta, CEDARS allow good separation at high momenta (300 GeV/c), but are more complicated and need careful tuning. For e/p separation XCET’s are usually operated with Helium or Nitrogen at pressures between 20 mbar and 3 bar. Summer 2007 Summer Student Workshop CEDAR Cerenkov counters Use that Cerenkov light is emitted at a fixed angle for given p and m Protect the 8 PM’s with a diaphragm that lets through only the light emitted at a given angle (for the wanted particle type). Needs a very parallel beam (i.e. only for hadron and electron beams). Summer 2007 Summer Student Workshop Simulated light spot at PM plane: Accept event if coincidence in at least 6, 7 or 8 PM’s (depending on requirements on purity and efficiency) E.g. p/K separation at 75 GeV/c in West type Cedar: Diaphragm PMT’s Summer 2007 Summer Student Workshop Experimental scalers Rather than reading our instruments, the NIM signal from any detector in an experiment can be connected to a BI scaler. This allows to count the rate in that detector as a function of beam settings. This is very useful for beam tuning, as it is the end user who counts! • • The final beam definition for the experiment must come from the experiment Often experiments take rates that are too high for a single counter. They can make logical combinations of several counters locally (and fast) and send a pre-scaled signal to our EXPT scaler. For small test areas, there are 4 scalers per barrack For big experiments, there are up to 20 scalers (NA48, NA60) Summer 2007 Summer Student Workshop CALORIMETER HV Principle: Computer Beam Particles shower in the lead-glass block. At the end of the shower, the small energy quanta remaining deposit their energy in the form of light. The light is captured by a photomultiplier that transforms it into an electrical pulse. The amount of light (thus the electrical signal) is proportional to the deposited energy. As the energy is deposited in N quanta, the relative precision of the measurement is limited by statistical fluctuations on N, i.e. : s(E)/E ~ 1/E Normally a calorimeter is used for energy measurements, But in our case its main use is for particle identification. Summer 2007 Summer Student Workshop Electron shower: Regular Fully contained: Hadron shower: Irregular, Partly contained: Muon shower: dE/dx Summer 2007 Only dE/dx Constant, small Summer Student Workshop Particle identification via: Ebeam Muons Summer 2007 Hadrons Summer Student Workshop Electrons Access to areas PPX Area PPE Whenever persons enter the beam area, the beam must be switched off. In the case of the X7A this guaranteed by switching off all bends. Instead of following the beam axis, all particles go straight, ‘miss the bend’ and are absorbed in a fixed iron beam dump (2.4 metres of iron). In order to enter the area, each person must take a key at the PPE door. As long as a key is missing from the door, the magnets cannot be switched on. Summer 2007 Summer Student Workshop The workshop will take place in the H6 beam: This is a high-energy hadron, electron and muon test beam Properties of the H6 beam: Parameter Value Maximum beam momentum [GeV/c] Maximum momentum band ±1.3% Momentum resolution Acceptance (mrad) – Horizontal Vertical < 0.1% ± 1.1 ± 1.3 Maximum flux per SPS cycle: **) Extreme radioprotection limit Summer 2007 205 Summer Student Workshop < 108 **) Secondary target H6 optics - test beam mode Summer 2007 Summer Student Workshop Summer 2007 Summer Student Workshop The H6 beam line is located in EHN1, building 887: Summer 2007 Summer Student Workshop Seen from the sky: EHN1 NA48, NA60 ≈ 550 meters H6 Compass CCC Summer 2007 Summer Student Workshop During the workshop you will be working in the CCC (i.e. the new CERN Control Center) in building 874. Summer 2007 Summer Student Workshop Thanks to: Edda Gschwendtner EA physicist Ilias Efthymiopoulos “ Bruno Chauchaix “ Olav Ullaland – Workshop coordinator, bus These slides can be found at: http://cern.ch/gatignon/TrainingSummerStudents2007.ppt Summer 2007 Summer Student Workshop