S A I D - H E L P short version from online help with a few extensions Mainz, June 4, 1999 LOGIN: telnet said.phys.vt.edu telnet fphws01.physik.uni-karlsruhe.de GRAPHICS: xwindow Tektronix (best for telephone connections and in cases of firewalls) e.g. Tera Term Pro version 2.3 for Windows 95/NT http://www.vector.co.jp/authors/VA002416/teraterm.html ftp://riksun.riken.go.jp/pub/pc/misc/terminal/teraterm/ SAID- Scattering Analysis Interactive Dialin, is a computer-interactive package of FORTRAN programs and data bases designed to encode and exhibit information on two-body elastic scattering amplitudes. A transaction file is recorded throughout the interaction which can be acquired for hard-copy or for further manipulation. DATA Entry- A set of FORTRAN "DATA" routines decode all entries. Numbers must be separated by blanks (or +/- signs) and must NOT run past column 72. Any no. of lines may be used. If "GON" is entered, "N" is used to move to the desired SAID "task" region. (eg GO2 will go to solution choice) PICTURES- Graphical output via "Tektronix" graphics is built into SAID. If pictures are desired, one must specify as a terminal type, one of the devices indicated by the "TERMINAL?" prompt. For X-windows enter "XW" * The terminal prompt can be brought back at any time by entry of "HPT". A picture file is accumulated throughout the running of SAID even if a non-graphics terminal is used. This file can then be converted to Postscript (.ps) pictures for transmission back to the user following the transaction. ************************************************************************* You will be prompted through the program. The following "special" input will allow you to "move about" the program. Either the pneumonic , or it's GON equivalent may be used (eg CHI2 is the same as GO5). HELP(GO1, or ?)- Got to the MENU for selecting the desired "task" * SOLU(GO2 )- Define a solution (you will be offered a choice) * KINE(GO3 )- Define reaction (PP,NP,PI+P...) and kinematics(energy,angle) * OBSE(GO4 )- Define data type to be plotted (DSG, P, etc.; or amplitudes) This must follow "GO3" where kinematics are defined. CHI2(GO5 )- Calculate CHI2 and normalizations for a range of energies from the Master data file, and for the present solution. SAMP(GO6 )- Change from observables to amplitudes and vice versa. This only works for the NN program. * PWAM(GO7 )- Display partial wave amplitudes (eg Phase or Argand plots) PLAN(GO8 )- Enter new ,or conjectured, data and plan measurements. DBAS(GO11)- Bin and Plot the "data-base" by Type and date of experiments GO21 - Bin and list alphabetically the Data References * GO51 - Reads in an ALTERNATE solution that can be used to graphically compare to the first. * GO60 - Does a CONTOUR(or 3-D) plot of predictions. The plotted quantity can be predictions from the PRIMARY solution or DIFFERENCES between the PRIMARY and ALTERNATE solutions. CONV(GO20)- Kinematic conversions, converts energy or angular variables. LAB-CM conversions of Energy, Angle, Mom-xfer etc. CORR(GO14)- Display Correlation Matrix for Single Energy solutions INTE(GO15)- Write an "interpolation" array to FOR015 which can be called through a FORTRAN subroutine (NNAMP, or PNAMP) to get very accurate and efficient on-shell amplitude reconstruction. NOT available for PION-PHOTOPRODUCTION. STOP(GO99)- Stop the show and EXITS. HELP(? )- Return to these instructions. PROD(GO25)- Display Pion production amplitudes (for PiN program only) MOVI(GO30)- Plot observables as "Movies",(eg watch angular distributions evolve as a function of energy; displays data within the energy-angle region being plotted. "GOn" (GO1,GO2,GO3...) or the Pneumonic equivalent (SOLN, CHI2....) can be entered any time input is requested. It is used to move around in the program as described in previous instructions. Kinematics KINE(GO3): Either reaction (PP,PI-P...) is calculated with one variable (energy or angle) fixed while the other (angle or energy) is to be specified * over a range (MIN INC MAX). The number of increments cannot exceed * 80. If INC=0, a MAXIMUM no of increments will be chosen for the plots. The energy variable can be chosen as TLAB, PLAB, or WCM (all in Mev) Partial Wave Amplitudes PWAM(GO7): The partial waves are calculated and printed in a delta-rho representation (eta=cos(rho)). They can be plotted directly or as an argand plot (TR,TI). "SINGLE ENERGY" values are the result of banded fits at the energies in question. For Pion-Photoproduction the * MULTIPOLES are given as Real/Imagin. in mFm = 139.65/197.32 10^-3/mu. * = 0.7077 10^-3/mpiplus Solutions SOLU(GO2): You will be shown a menu of solutions to choose from. Pick one which best represents the reaction you wish to study (nearest energy, etc.). The "best" values probably come from the energy-dependent solutions but the "best" estimate of errors probably comes from the nearest single-energy solution which has an error matrix. Be careful not to calculate NP observables from a PP only solution. If you enter "OWN" when asked for a solution, an energy dependent solution named "OWN" will be read and you will be allowed to input phases at a desired energy. "CHANGE" will allow modification of the solution which was previously being used. You could change single phases and measure the effect on various observables. An "alternate" solution file can be connected to by entry of "V " when prompted for a solution title. This allows access to ones own solutions if they are properly structured and sent to VPI. Caution!! NEVER use a solution OUTSIDE it's range of validity. EXTRAPOLATION properties are generally VERY bad. If the solution NAME is entered as "SES" a single-energy solution is used and a diagonal ERROR MATRIX is created using the errors obtained in the binned analysis which produced the partial-waves. Chisquared CHI2(GO5): Comparison of solution predictions to experimental quantities are made to the Scattering Data file. Experiments can be selected by energy-range , short reference, type, or date. If the MAXimum energy (you will be prompted for Emin Emax) is negative, a point-by point comparison is made Planning experiments, PLAN(GO8): Solutions are used to "plan" experiments by adding hypothetical (or real data) data to the base from which the solution was derived. The phase parameters are adjusted implicitly to give a "best" fit to the combined set. Sensitivities can thus be probed and kinematic ranges can be determined for maximum effectiveness. Observables-Amplitudes SAMP(GO6): (NN program only) The program is set to calculate scattering observables (cross section, pol, etc.); scattering amplitudes (Wolfenstein parameters and helicity amplitudes) can also be obtained. ************************************************************************* For Pion-photoproduction There are 4 charge channels; 1(pi0) and 2(pi+) from proton targets. 3(pi-) and 4(pi0n) are from neutron targets. Iso-spin Clebsch-Gordon coefficients to these channels are: React I pi0 I pi+ I pi- I pi0n ----------I-----I-------I------I-------- I=1/2 I 1 I SQ I SQ I -1 -------I-----I-------I------I------ SQ=Sqrt(2) I=3/2 I 2/3 I -SQ/3 I SQ/3 I 2/3 ----------I-----I-------I------I-------- There are 4 Helicity amplitudes composed as (SUMMED) product of I-spin C-G, Spectroscopic factor, and Electric(or Magnetic) Multipole. ************************************************************************* Definition of Multipole Amplitudes used in SAID (mjl numbering) mjl=100*m+10*j+l where l=orbital angular momentum, j=1,2 for l-, l+ and m=1(pE3/2), 2(pM3/2), 3(pE1/2), 4(pM1/2), 5(nE1/2), 6(nM1/2) The following table is "useful". Connected pi-n elastic waves are in box I I j=2 I j=1 I j=2 I j=1 I j=2 I j=1 I j=2 I -------------------------------------------------------------- m I I l=0+ I l=1- I l=1+ I l=2- I l=2+ I l=3- I l=3+ I -------------------------------------------------------------- 1 I pE3/2 I S31 I x I P33 I D33 I D35 I F35 I F37 I -------------------------------------------------------------- 2 I pM3/2 I x I P31 I P33 I D33 I D35 I F35 I F37 I -------------------------------------------------------------- 3 I pE1/2 I S11 I x I P13 I D13 I D15 I F15 I F17 I -------------------------------------------------------------- 4 I pM1/2 I x I P11 I P13 I D13 I D15 I F15 I F17 I -------------------------------------------------------------- 5 I nE1/2 I S11 I x I P13 I D13 I D15 I F15 I F17 I -------------------------------------------------------------- 6 I nM1/2 I x I P11 I P13 I D13 I D15 I F15 I F17 I -------------------------------------------------------------- -------------------------------------------------------------- ************************************************************************* Observables defined as in Barker et al, NPB95, 347(1975) k=photon mom, q=pion mom z=k(unit vect) y=kxq(unit vect) x=yxz c=circular polarization z'=q(unit vect) y'=y x'=yxz' h1..h4=helicity amps=S1,N,D,S2 (in Barker Notation) (proportional) Experiments are defined by: [Pg,Pt,Pr] (photon,target,recoil) pol SAID amplitudes are in mFm, Cross sections are in microbarns defining Sum=|h1|**2+|h2|**2+h3|**2+h4|**2 L(th,th') means linear pol at angles th,th' to scattering plane "Experiment" are those which will measure observable. Symbol Experiment Helicity Rep ------------------------------------------------------------------------ dSigma/dOmega [-,-,-] q/k/2*Sum S S*Sum [-,y,y] 2Re[h1*h4-h3*h2] type or [L(pi/2,0),-,-] T*Sum [-,y,-] 2Im[h2*h1-h3*h4] or [L(pi/2,0),-,y] P*Sum [-,-,y] 2Im[h2*h4-h3*h1] or [L(pi/2,0),y,-] ------------------------------------------------------------------------ G*Sum [L(pi/4,-pi/4),z,-] 2Im[h1*h4+h2*h3] BT H*Sum [L(pi/4,-pi/4),x,-] 2Im[h1*h3+h4*h2] type E*Sum [c,z,-] |h4|**2-|h1|**2-|h3|**2+|h2|**2 F*Sum [c,x,-] 2Re[h3*h4+h2*h1] ------------------------------------------------------------------------ Ox*Sum [L(pi/4,-pi/4),-,x'] 2Im[h4*h3+h1*h2] BR Oz*Sum [L(pi/4,-pi/4),-,z'] 2Im[h1*h4+h3*h2] type Cx*Sum [c,-,x'] -2Re[h2*h4+h3*h1] Cz*Sum [c,-,z'] |h4|**2-|h1|**2-|h2|**2+|h3|**2 ------------------------------------------------------------------------ Tx*Sum [-,x,x'] 2Re[h1*h4+h3*h2] TR Tz*Sum [-,x,z'] 2Re[h2*h1-h3*h4] type Lx*Sum [-,z,x'] 2Re[h2*h4-h3*h1] Lz*Sum [-,z,z'] |h1|**2+|h4|**2-|h2|**2-|h3|**2 ------------------------------------------------------------------------ ************************************************************************* Choices of photoproduction observables are (e.g. option GO4) (DSG ) (P ) (S ) (T ) (SGT ) (G ) (H ) (EMRI) (E ) (F ) (OX ) (OZ ) (CX ) (CZ ) (TX ) (TZ ) (LX ) (LZ ) (ST3 ) (ST1 ) (ST13) e.g. DSG : differential cross section P : recoil polarization S : photon asymmetry \Sigma T : target asymmetry ST1 : total cross section with helicity 1/2 ST3 : total cross section with helicity 3/2 * ST13: ST1-ST3 SGT : total cross section = (ST1+ST3)/2