Description of atsummary

0001 function sum = atsummary
0002 %ATSUMMARY - Prints out the paramters of the current AT lattice
0003 %  The parameters that come after the Synchrotron Integrals are
0004 %  parameters that depend on the Integrals themselves. The equations to
0005 %  calculate them were taken from [1].
0006 %
0007 %  [1] Alexander Wu Chao and Maury Tigner, Handbook of Accelerator Physics
0008 %  and Engineering (World Scientific, Singapore, 1998), pp. 183-187. (or
0009 %  187-190 in ed. 2)
0010 %
0011 %  See also ringpara
0012 
0013 %  Written by Eugene Tan
0014 %  Revised by Laurent S. Nadolski
0015 
0016 
0017 global THERING
0018 
0019 % Structure to store info
0020 %sum.e0 = getenergy('Model');
0021 sum.e0 = atenergy(THERING);
0022 sum.circumference = findspos(THERING, length(THERING)+1);
0023 sum.revTime = sum.circumference / 2.99792458e8;
0024 sum.revFreq = 2.99792458e8 / sum.circumference;
0025 sum.gamma = sum.e0 / 0.51099906e-3;
0026 sum.beta = sqrt(1 - 1/sum.gamma);
0027 [TD, sum.tunes, sum.chromaticity] = twissring(THERING, 0, 1:length(THERING)+1, 'chrom', 1e-8);
0028 sum.compactionFactor = mcf(THERING);
0029 
0030 % For calculating the synchrotron integrals
0031 temp  = cat(2,TD.Dispersion);
0032 D_x   = temp(1,:)';
0033 D_x_  = temp(2,:)';
0034 beta  = cat(1, TD.beta);
0035 alpha = cat(1, TD.alpha);
0036 gamma = (1 + alpha.^2) ./ beta;
0037 circ  = TD(length(THERING)+1).SPos;
0038 
0039 % Synchrotron integral calculation
0040 sum.integrals = [0.0 0.0 0.0 0.0 0.0 0.0];
0041 
0042 for i = 1:length(THERING),
0043     if isfield(THERING{i}, 'BendingAngle') && isfield(THERING{i}, 'EntranceAngle')
0044         rho = THERING{i}.Length/THERING{i}.BendingAngle;
0045         dispersion = 0.5*(D_x(i)+D_x(i+1));
0046         sum.integrals(1) = sum.integrals(1) + dispersion*THERING{i}.Length/rho;
0047         sum.integrals(2) = sum.integrals(2) + THERING{i}.Length/(rho^2);
0048         sum.integrals(3) = sum.integrals(3) + THERING{i}.Length/(rho^3);
0049         % For general wedge magnets
0050         sum.integrals(4) = sum.integrals(4) + ...
0051             D_x(i)*tan(THERING{i}.EntranceAngle)/rho^2 + ...
0052             (1 + 2*rho^2*THERING{i}.PolynomB(2))*(D_x(i)+D_x(i+1))*THERING{i}.Length/(2*rho^3) + ...
0053             D_x(i+1)*tan(THERING{i}.ExitAngle)/rho^2;
0054         %         sum.integrals(4) = sum.integrals(4) + 2*0.5*(D_x(i)+D_x(i+1))*THERING{i}.Length/rho^3;
0055         H1 = beta(i,1)*D_x_(i)*D_x_(i)+2*alpha(i)*D_x(i)*D_x_(i)+gamma(i)*D_x(i)*D_x(i);
0056         H0 = beta(i+1,1)*D_x_(i+1)*D_x_(i+1)+2*alpha(i+1)*D_x(i+1)*D_x_(i+1)+gamma(i+1)*D_x(i+1)*D_x(i+1);
0057         sum.integrals(5) = sum.integrals(5) + THERING{i}.Length*(H1+H0)*0.5/(rho^3);
0058         %         if H1+H0 < 0
0059         %             fprintf('%f %i %s\n', H1+H0, i, THERING{i}.FamName)
0060         %         end
0061         sum.integrals(6) = sum.integrals(6) + THERING{i}.PolynomB(2)^2*dispersion^2*THERING{i}.Length;
0062     end
0063 end
0064 
0065 % Damping numbers
0066 % Use Robinson's Theorem
0067 sum.damping(1) = 1 - sum.integrals(4)/sum.integrals(2);
0068 sum.damping(2) = 1;
0069 sum.damping(3) = 2 + sum.integrals(4)/sum.integrals(2);
0070 
0071 sum.radiation = 8.846e-5*sum.e0.^4*sum.integrals(2)/(2*pi);
0072 sum.naturalEnergySpread = sqrt(3.8319e-13*sum.gamma.^2*sum.integrals(3)/(2*sum.integrals(2) + sum.integrals(4)));
0073 sum.naturalEmittance = 3.8319e-13*(sum.e0*1e3/0.510999).^2*sum.integrals(5)/(sum.damping(1)*sum.integrals(2));
0074 
0075 % Damping times
0076 sum.radiationDamping(1) = 1/(2113.1*sum.e0.^3*sum.integrals(2)*sum.damping(1)/circ);
0077 sum.radiationDamping(2) = 1/(2113.1*sum.e0.^3*sum.integrals(2)*sum.damping(2)/circ);
0078 sum.radiationDamping(3) = 1/(2113.1*sum.e0.^3*sum.integrals(2)*sum.damping(3)/circ);
0079 
0080 % Slip factor
0081 sum.etac = sum.gamma^(-2) - sum.compactionFactor;
0082 
0083 cavind = findcells(THERING,'HarmNumber');
0084 if ~isempty(cavind)
0085     freq = THERING{cavind}.Frequency;
0086     v_cav = THERING{cavind}.Voltage;
0087 else
0088     % Default
0089     freq = 352.202e6;
0090     v_cav = 3e6;
0091 end
0092 sum.harmon = sum.circumference/(2.99792458e8/freq); % Assuming 499.654MHz RF
0093 sum.overvoltage = v_cav/(sum.radiation*1e9); % Assuming 3e6 volt cavities.
0094 % Assuming the harmon and overvoltage above.
0095 % references:  H. Winick, "Synchrotron Radiation Sources: A Primer",
0096 % World Scientific Publishing, Singapore, pp92-95. (1995)
0097 % Wiedemann, pp290,350. Chao, pp189.
0098 sum.syncphase = pi - asin(1/sum.overvoltage);
0099 sum.energyacceptance = sqrt(v_cav*sin(sum.syncphase)*2*(sqrt(sum.overvoltage^2-1) - acos(1/sum.overvoltage))/(pi*sum.harmon*abs(sum.etac)*sum.e0*1e9));
0100 sum.synctune = sqrt((sum.etac*sum.harmon*v_cav*cos(sum.syncphase))/(2*pi*sum.e0*1e9));
0101 sum.bunchlength = sum.beta*299792458*abs(sum.etac)*sum.naturalEnergySpread/(sum.synctune*sum.revFreq*2*pi);
0102 
0103 if nargout == 0
0104     fprintf('\n');
0105     %fprintf('   ******** Summary for ''%s'' ********\n', GLOBVAL.LatticeFile);
0106     fprintf('   ******** AT Lattice Summary ********\n');
0107     fprintf('   Energy: \t\t\t%4.5f [GeV]\n', sum.e0);
0108     fprintf('   Gamma: \t\t\t%4.5f \n', sum.gamma);
0109     fprintf('   Circumference: \t\t%4.5f [m]\n', sum.circumference);
0110     fprintf('   Revolution time: \t\t%4.5f [ns] (%4.5f [MHz]) \n', sum.revTime*1e9,sum.revFreq*1e-6);
0111     fprintf('   Betatron tune H: \t\t%4.5f (%4.5f [kHz])\n', sum.tunes(1),sum.tunes(1)/sum.revTime*1e-3);
0112     fprintf('                 V: \t\t%4.5f (%4.5f [kHz])\n', sum.tunes(2),sum.tunes(2)/sum.revTime*1e-3);
0113     fprintf('   Momentum Compaction Factor: \t%4.5f\n', sum.compactionFactor);
0114     fprintf('   Chromaticity H: \t\t%+4.5f\n', sum.chromaticity(1));
0115     fprintf('                V: \t\t%+4.5f\n', sum.chromaticity(2));
0116     fprintf('   Synchrotron Integral 1: \t%4.5f [m]\n', sum.integrals(1));
0117     fprintf('                        2: \t%4.5f [m^-1]\n', sum.integrals(2));
0118     fprintf('                        3: \t%4.5f [m^-2]\n', sum.integrals(3));
0119     fprintf('                        4: \t%4.5f [m^-1]\n', sum.integrals(4));
0120     fprintf('                        5: \t%4.5f [m^-1]\n', sum.integrals(5));
0121     fprintf('                        6: \t%4.5f [m^-1]\n', sum.integrals(6));
0122     fprintf('   Damping Partition H: \t%4.5f\n', sum.damping(1));
0123     fprintf('                     V: \t%4.5f\n', sum.damping(2));
0124     fprintf('                     E: \t%4.5f\n', sum.damping(3));
0125     fprintf('   Radiation Loss: \t\t%4.5f [keV]\n', sum.radiation*1e6);
0126     fprintf('   Natural Energy Spread: \t%4.5e\n', sum.naturalEnergySpread);
0127     fprintf('   Natural Emittance: \t\t%4.5e [mrad]\n', sum.naturalEmittance);
0128     fprintf('   Radiation Damping H: \t%4.5f [ms]\n', sum.radiationDamping(1)*1e3);
0129     fprintf('                     V: \t%4.5f [ms]\n', sum.radiationDamping(2)*1e3);
0130     fprintf('                     E: \t%4.5f [ms]\n', sum.radiationDamping(3)*1e3);
0131     fprintf('   Slip factor : \t%4.5f\n', sum.etac);
0132     fprintf('\n');
0133     fprintf('   Assuming cavities Voltage: %4.5f [kV]\n', v_cav/1e3);
0134     fprintf('                   Frequency: %4.5f [MHz]\n', freq/1e6);
0135     fprintf('             Harmonic Number: %4.5f\n', sum.harmon);
0136     fprintf('   Overvoltage factor: %4.5f\n', sum.overvoltage);
0137     fprintf('   Synchronous Phase:  %4.5f [rad] (%4.5f [deg])\n', sum.syncphase, sum.syncphase*180/pi);
0138     fprintf('   Linear Energy Acceptance:  %4.5f %%\n', sum.energyacceptance*100);
0139     fprintf('   Synchrotron Tune:   %4.5f (%4.5f kHz or %4.2f turns) \n', sum.synctune, sum.synctune/sum.revTime*1e-3, 1/sum.synctune);
0140     fprintf('   Bunch Length:       %4.5f [mm]\n', sum.bunchlength*1e3);
0141 end
atsummary

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