Warning, /eic.github.io/_software/beagle.md is written in an unsupported language. File is not indexed.
0001 ---
0002 title: BeAGLE
0003 name: beagle
0004 category: beagle
0005 layout: default
0006 ---
0007
0008 {% include layouts/title.md %}
0009 * TOC
0010 {:toc}
0011
0012
0013 #### About
0014
0015 BeAGLE - **B**enchmark **eA** **G**enerator for **LE**ptoproduction
0016
0017 **The source code of BeAGLE can be found [here](https://github.com/eic/BeAGLE)**
0018
0019 **[Latest version can be found in the most recent tag](https://github.com/eic/BeAGLE/tags)**
0020
0021 <left>
0022 {% include images/image.md name='beagleAsciiLogo' width='400' %}
0023 </left>
0024
0025
0026 **Contacts:**
0027 * Kong Tu <zhoudunming@bnl.gov>
0028
0029
0030 #### Program Overview
0031
0032 BeAGLE uses the [DPMJet](https://wiki.bnl.gov/eic/index.php/DPMJet) framework in order to handle the target
0033 (Glauber, FLUKA etc.) for ep and eA collisions but employs [PYTHIA](https://eic.github.io/software/pythia6.html)
0034 to handle the elementary interaction as a replacement for PHOJET. The nuclear PDF is included by linking the
0035 PYTHIA PDF library to LHAPDF which enables us access to EPS09 nuclear PDF routines. We have included the
0036 energy loss module PyQM, written by Accardi and Dupre and based on the quenching weights of
0037 Salgado & Wiedemann. This module, when turned on, applies energy loss to the partons after they have
0038 been simulated by Pythia, but before they have been hadronized.
0039
0040 The original DPMJet models DTUNUC, PHOJET, QNEUTRIN are NOT available in BeAGLE.
0041 If you are interested in these models for pp/pA, real photoproduction, or quasi-elastic neutrino scattering,
0042 use [DPMJet](https://wiki.bnl.gov/eic/index.php/DPMJet) directly. The history and motivation of the use of
0043 DPMJetHybrid rather than DPMJet for eRHIC can be
0044 found [here](https://wiki.bnl.gov/eic/index.php/DpmjetHybrid#Opening_issue).
0045
0046 A graphical demonstration of the program structure can be illustrated as follows:
0047 <center>
0048 {% include images/image.md name='beagle_design' width='732' %}
0049 </center>
0050
0051 #### Basic Model
0052 The program can be run in, essentially, two modes.
0053
0054 Setting ```genShd=1``` (generator Shadowing=1) is similar to DPMJetHybrid. The entire nuclear shadowing
0055 effect (where R=σ(A)/Aσ(p)<1) is interpreted as a change in the parton distribution of unspecified origin,
0056 but the DIS interaction is assumed to be point-like. One and only one nucleon participates in the interaction.
0057
0058 Note: This approach is in stark contrast to the original DPMJET approach which used GMVD (Generalized Vector Meson Dominance) and allowed multiple collisions.
0059
0060 Setting ```genShd>1``` (specifically 2 or 3) activates a very simplistic model of nuclear shadowing loosely based on the dipole-model or aligned-jet model. Even for DIS events, the scattering process in the target rest frame is viewed as being due to a rare hadronic fluctuation of the virtual photon with a very large cross-section (few mb). In this case, the **entire** R(x,Q2)<1 shadowing effect is attributed to multiple nucleon collisions. Viewed in the hadronic center-of-mass frame, such collisions can still look like conventional DIS.
0061
0062 We implement this by making a map, outside of BeAGLE, using ```TGlauberMC``` between the "dipole" cross-section σ and the value of R. When running BeAGLE, we look up R in the nPDF (such as EPS09) and find the corresponding dipole cross-section. Using the dipole cross-section, we can then simulate the collisions with Glauber, leading to a variety of ```Ncoll``` values. If ```Ncoll>1```, we currently pick one of the struck nucleons to undergo a Pythia interaction (for ```genShd=2```, this is a random choice among the struck nucleons; for ```genShd=3``` it is the first struck nucleon seen by the γ<sup>*</sup>). Any additional struck nucleons undergo an elastic scatter with the most forward parton (in the direction of the γ<sup>*</sup>) with a pt magnitude of a typical intrinsic kt.
0063
0064 It should be noted that for x<sub>Bj</sub>>0.1 or R>1, we revert to ```genShd=1``` behavior.
0065
0066 At the moment, there are many simplifying assumptions for the multinucleon mode, made for convenience, which we hope to systematically relax as we upgrade the program. These include:
0067
0068
0069
0070 > Infinite coherence length even at modest x. <br/>
0071 > We apply an overall multinucleon effect based on the R<sub>sea</sub>(x,Q<sup>2</sup>) independent of process. <br/>
0072 > Note: Processes such as Photon-Gluon Fusion should depend of R<sub>G</sub> while diffraction should INCREASE as R gets smaller. <br/>
0073 > We assume that the full shadowing effect is due to multinucleon collisions with no modification of individual nucleons.
0074
0075 #### How to run BeAGLE, step-by-step instructions
0076 *<font color="blue">Contact persons: Mark Baker (mdbaker@bnl.gov), Kong Tu(zhoudunming@bnl.gov)</font>*
0077
0078
0079 **<font size="5">Overview</font>**
0080
0081 There are two central managed directory/repo stored at BNL,
0082 * PACKAGES:
0083 ````
0084 /afs/rhic/eic/PACKAGES/BeAGLE
0085 ````
0086 * Gitstore:
0087 ````
0088 /afs/rhic/eic/gitstore/BeAGLE
0089 ````
0090
0091 Never run BeAGLE from these two directories and please follow the instructions below. These two directories are kept exactly identical. The ``PACKAGES`` is the official version, while the gitstore version could be updated by the developers from time to time.
0092
0093 **<font size="5">Users only</font>**
0094
0095 Make a new directory, e.g., run-BeAGLE-Name,
0096 ````
0097 mkdir run-BeAGLE-Kong
0098 cd run-BeAGLE-Kong
0099 ````
0100
0101 Copy the fluka nuclear data file:
0102 ````
0103 cp /afs/rhic/eic/PACKAGES/BeAGLE/nuclear.bin . (for BNL)
0104 cp /u/group/ldgeom/PACKAGES/BeAGLE/nuclear.bin . (for JLAB)
0105 ````
0106
0107 Source setup_BeAGLE to setup your environment variable $BEAGLESYS, which will point to the BeAGLE directory, e.g., the PACKAGES directory. One can also source the same thing under the gitstore version.
0108 ````
0109 source /afs/rhic/eic/PACKAGES/BeAGLE/setup_BeAGLE (for BNL)
0110 source /u/group/ldgeom/PACKAGES/BeAGLE/setup_BeAGLE (for JLAB)
0111 ````
0112 when done, ``$BEAGLESYS/BeAGLE`` will be the executable.
0113
0114 **<font size="5">Developers</font>**
0115
0116 Make a new directory, e.g., BeAGLE-dev-Name-Date,
0117 ````
0118 mkdir BeAGLE-dev-Kong-2020-01-29
0119 cd BeAGLE-dev-Kong-2020-01-29
0120 ````
0121
0122 git clone the developer's area,
0123 ````
0124 git clone /afs/rhic/eic/gitstore/BeAGLE
0125 cd BeAGLE
0126 cp /afs/rhic/eic/gitstore/BeAGLE/RAPGAP-3.302/lib/*.a ./RAPGAP-3.302/lib/
0127 make all
0128 ````
0129
0130 The executable will be under the main directory, called "BeAGLE". So instead of
0131 running the executable from central directory, one runs from here locally. See later on ``running instructions.``
0132
0133 **<font size="5">Running the code</font>**
0134
0135 Copy your own input files, there are at least two of them are necessary,
0136 BeAGLE input control card, \*.inp, and Pythia/Rapgap input control card, S\*, e.g, S3ALL003
0137 ````
0138 cp -rf /gpfs02/eic/ztu/BeAGLE/BeAGLE_examples-2022-01-11/inputFiles ./
0139 cp /gpfs02/eic/ztu/BeAGLE/BeAGLE_examples-2022-01-11/S* ./
0140 ````
0141
0142 Create your own output directory,
0143 ````
0144 mkdir outForPythiaMode
0145 ````
0146
0147 Copy and paste the macro to convert text output to root output, e.g.,
0148 ````
0149 cp /gpfs02/eic/ztu/BeAGLE/BeAGLE_examples-2022-01-11/BuildIt.C ./
0150 ````
0151
0152 To run BeAGLE, do this following command under the main directory,
0153 * for users running:
0154 ````
0155 $BEAGLESYS/BeAGLE < inputFiles/yourinput.inp > log_file_name.txt
0156 ````
0157 * for developers running locally:
0158 ````
0159 ./BeAGLE < inputFiles/yourinput.inp > log_file_name.txt
0160 ````
0161 the output will be under outForPythiaMode, with a common name. Overwrite the name to xxx.txt.
0162
0163 Go back to main directory, and run:
0164 ````
0165 root -b -q 'BuildIt.C("xxx.txt")'
0166 ````
0167 the root file will have the same name as the txt file.
0168
0169
0170 To analyze the root file, one can loop over events AND particles
0171 and do analysis. One example macro is provided under
0172 ````
0173 /gpfs02/eic/ztu/BeAGLE/BeAGLE_examples-2022-01-11/runEICTree.C
0174 ````
0175
0176 Grab necessary parts for what's needed.
0177 Then simply do:
0178 ````
0179 root -l runEICTree.C+\(\"filename\"\)
0180 ````
0181
0182 The filename is without the .root extension.
0183 Note: In order to access EventBeagle (which is defined under EventPythia.h), and besides to setup eic_cshrc, one needs to setup include path to /afs/rhic.bnl.gov/eic/include, For example, if one is not sure, open root, and try,
0184 ````
0185 gSystem->GetIncludePath()
0186 ````
0187 See if ``-I/afs/rhic.bnl.gov/eic/include`` was added. If not, you need to add the include path.
0188
0189
0190 #### BeAGLE Control Card
0191 Note: This input file (originally from DPMJET) is very particular about the spacing of a lot of the numbers so make sure that you leave the starting space the same when you change numbers. In particular, the input format is: A10, 6E10.0, A8
0192
0193 Frequently changed cards:
0194 ```
0195 START - the first # is the # of events requested.
0196 TARPAR - the first # is A and the second # is Z for the target
0197 the third # is the n/p handling mode for the Pythia subevent:
0198 0=sequential n,p. The first ~N/A events are en, the remaining ep (binomial prob.)
0199 Useful for getting en & ep cross-sections from Pythia
0200 1=en only test mode (not really for physics)
0201 2=ep only test mode (not really for physics)
0202 3=random mix. The events are randomly en or ep.
0203 Useful because you can analyze just a subset of the data without bias.
0204 TAUFOR - the first # is the formation time parameter (tau) in fm/c for the intranuclear cascade
0205 the second # is the number of generations followed Default=25, 0 means no cascade
0206 MOMENTUM - the first # is for the lepton beam (GeV/c), the second for the A (or p)
0207 both #s should be entered as positive, but the lepton beam will be multiplied by -1.
0208 L-TAG - these #s are cuts: yMin yMax Q2Min Q2Max thetaMin thetaMax
0209 where y & Q2 (GeV2) are the leptoproduction kinematics
0210 and theta (radians) refers to the lepton scattering angle in the laboratory frame.
0211 PY-INPUT - specifies the file (with an eight-character maximum name!) used as a pythia input file.
0212 Examples (such as eAS2noq) can be found in the /afs/rhic/EIC/PACKAGES/BeAGLE/ directory.
0213 FERMI - First # means: -1 = no Fermi motion at all
0214 1 = DPMJET Fermi motion, but Pythia subevent neglects it (DPMJetHybrid mode)
0215 2 = Fermi motion added to Pythia subevent after the fact
0216 3 = Pythia subevent used correct Fermi motion (Not Yet Implemented)
0217 Second #: "Scale factor" for Fermi momentum distribution in GeV (0.62 is default, don't touch it unless instructed to do so)
0218 Third #: Fermi momentum distribution 0 (D) = Most recommended distribution
0219 Fourth #: Post-processing flag: (Not Yet Implemented)
0220 0 (D) = no post-processing
0221 1 = Fix energy non-conservation in ion frame (for small nuclei)
0222 FSEED - Uncomment/comment this line for debugging/production
0223 OUTLEVEL - First 4 #s are verbosity flags -1=quiet, >=1 increasing verbosity
0224 Fifth # is the number of events to print out and in some cases to be verbose about
0225 PYVECTORS - Allowed Pythia vector mesons for diffraction: 0(D)=all, 1=rho, 2=omega, 3=phi, 4=J/psi
0226 USERSET = First # specifies the meaning of the variables User1,User2,User3 (detailed below)
0227 Second # specifies the maximum excitation energy in GeV handed to Fluka (D=9.0)
0228 Note: This should not come into play, but it protects against infinite loops.
0229 PHOINPUT - Any options explained in the PHOJET-manual can be used in between
0230 the "PHOINPUT" and "ENDINPUT" cards.
0231 PROCESS - 1 1 1 1 1 1 1 1
0232 ENDINPUT -
0233
0234 The last two cards should be:
0235 START = First # specifies the # of events to run
0236 Second # should be 0 (or missing)
0237 STOP
0238 ```
0239 The ``USERSET`` are defined as in this [link.](https://gitlab.in2p3.fr/BeAGLE/BeAGLE/-/blob/master/src/dpmjet3.0-5F-new.f?expanded=true&viewer=simple#L2386) Be patient, it will need 30 secs to load the source code. For example, ``USERSET==16`` is to save the information of the Deuteron wavefunction.
0240
0241
0242 <font size="5">PYTHIA Control Card</font>
0243
0244 The format of the PY-INPUT file is similar to the Pythia input file, which is not really documented elsewhere, but is fairly self-explanatory due to the comments. See below.
0245
0246 ```yaml
0247 line 1: output file name for the textfile
0248 line 2: xmin and xmax
0249 line 3: ignored unless radcor is being used
0250 line 4: 0 switch for radcor. 0=off. 1=on. 2=generate tables. radcor>0 NOT YET TESTED.
0251 line 5: 1 GVMD model choice 0=x,Q2, 1=y,Q2
0252 line 6: 1,1 A-Tar and Z-Tar really only used if radcor is used.
0253 line 7: Shadowing/multinucleon switch genShd for BeAGLE. 1=1 nucleon struck.
0254 2=Glauber. Pythia-interacting nucleon chosen at random from struck nucleons. All others elastic scatter.
0255 3=like 2, but Pythia-interaction is the first (most negative z in TRF with +z along γ* direction) nucleon.
0256 line 8: 101 Means LO with error set 1 in the nuclear PDF.
0257 line 9: switch for quenching (1:on, 0:off) NOTE: quenching is NOT WELL TESTED yet.
0258 line 10: Qhat value for quenching (0.0 also means no quenching even if the switch=1)
0259 OPTIONAL LINE: FSEED ####### - Fixes seed for random # generator for debugging. Don't use for production.
0260 ```
0261 Other lines make changes to PYTHIA control parameters.
0262
0263 The usage and explanations for the parameters in the input file and what kind of parameters do we need to give for PYTHIA can be found in the following file:
0264 ```bash
0265 /afs/rhic/eic/PACKAGES/BeAGLE/Documents/Documentation
0266 ```
0267 To find the final state particles, just use the following selection rules:
0268 ```
0269 ISTHKK(i)=1
0270 ```
0271 which selects all the particles from hard interaction, nuclear evaporation and heavy nuclear fragments.
0272
0273 #### Output Data Format:
0274 The BeAGLE output is a text file intended to be read in by eic-smear and EicRoot at BNL and by GEMC at JLAB.
0275
0276 For the output file, we propose the following text format & structure:
0277 * 1st line: <tt>PYTHIA</tt> EVENT FILE
0278 * 2nd line: <tt>============================================</tt>
0279 * 3rd line: Information on event wise variables stored in the file:
0280
0281 | I: | I | 0 \(line index\) |
0282 |-------------------------------------------------------------------------------------------------------------------------------------------|---|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
0283 | ievent: | I | eventnumber running from 1 to XXX |
0284 | genevent: | I | trials to generate this event |
0285 | ltype: | I | particle code for incoming lepton |
0286 | Atarg: | I | A of the target nucleus |
0287 | Ztarg: | I | Z of the target nucleus |
0288 | pzlep: | D | lab pz of the lepton beam \(sign\(pz\)\*p for non\-zero crossing angle\) |
0289 | pztarg: | D | lab pz/A of the ion beam \(sign\(pz\)\*p/A for non\-zero crossing angle\) |
0290 | pznucl: | D | lab pz of the struck nucleon \(sign\(pz\)\*p for non\-zero crossing angle\) |
0291 | crang: | D | crossing\-angle \(mr\)\. ** NOT IMPLEMENTED YET ** crang = \(1000\*\) atan\(px/pz\) for the beam momentum with nonzero px\. Note: we assume one of the beams has px=py=0 and the other py=0\. |
0292 | crori: | I | crossing angle orientation. ** NOT IMPLEMENTED YET ** +/-1 lepton beam defines +/- z direction. +/-2 ion beam defines +/- z direction. 0 no crossing angle.|
0293 | subprocess: | I | pythia subprocess \(MSTI\(1\)\), for details see PYTHIA |
0294 | nucleon: | I | hadron beam type \(MSTI\(12\)\) |
0295 | targetparton: | I | parton hit in the target \(MSTI\(16\)\) |
0296 | xtargparton: | D | x of target parton \(PARI\(34\)\) |
0297 | beamparton: | I | in case of resolved photon processes and soft VMD the virtual photon has a hadronic structure\. This gives the info which parton interacted with the target parton \(MSTI\(15\)\) |
0298 | xbeamparton: | D | x of beam parton \(PARI\(33\)\) |
0299 | thetabeamparton: | D | theta of beam parton \(PARI\(53\)\) |
0300 | truey, trueQ2, truex, trueW2, trueNu: | D | are the kinematic variables of the event\. |
0301 | | | If radiative corrections are turned on they are different from what is calculated from the scattered lepton\. |
0302 | | | If radiative corrections are turned off they are the same as what is calculated from the scattered lepton |
0303 | leptonphi: | D | phi of the lepton \(VINT\(313\)\) in the laboratory frame |
0304 | s\_hat: | D | s\-hat of the process \(PARI\(14\)\) |
0305 | t\_hat: | D | Mandelstam t \(PARI\(15\)\) |
0306 | u\_hat: | D | Mandelstam u \(PARI\(16\)\) |
0307 | pt2\_hat: | D | pT2\-hat of the hard scattering \(PARI\(18\)\) |
0308 | Q2\_hat: | D | Q2\-hat of the hard scattering \(PARI\(22\)\), |
0309 | F2, F1, R, sigma\_rad, SigRadCor: | D | information used and needed in the radiative correction code |
0310 | EBrems: | D | energy of the radiative photon in the nuclear rest frame |
0311 | photonflux: | D | flux factor from PYTHIA \(VINT\(319\)\) |
0312 | b: | D | Impact parameter \(in fm\), radial position of virtual photon w\.r\.t\. the center of the nucleus in the nuclear TRF with z along γ\* |
0313 | Phib: | D | azimuthal angle of the impact parameter of the virtual photon in the nuclear TRF with z along γ\* and φ=0 for the scattered electron |
0314 | Thickness: | D | Nuclear thickness T\(b\)/ρ0 in units of fm\. |
0315 | ThickScl: | D | Nuclear thickness T\(b\) in nucleons/fm2\. |
0316 | Ncollt: | I | Number of collisions between the incoming γ\* and nucleons in the nucleus \(same as number of participating nucleons\) |
0317 | Ncolli: | I | Number of inelastic collisions between the incoming γ\* and nucleons in the nucleus \(same as number of inelastically participating nucleons\) |
0318 | Nwound: | I | Number of wounded nucleons, including those involved in the intranuclear cascade\. WARNING: This variable is not finalized yet |
0319 | Nwdch: | I | Number of wounded protons, including those involved in the intranuclear cascade\. WARNING: This variable is not finalized yet |
0320 | Nnevap: | I | Number of evaporation \(and nuclear breakup\) neutrons |
0321 | Npevap: | I | Number of evaporation \(and nuclear breakup\) protons |
0322 | Aremn: | I | A of the nuclear remnant after evaporation and breakup |
0323 | Ninc: | I | Number of stable hadrons from the Intra Nuclear Cascade |
0324 | Nincch: | I | Number of charged stable hadrons from the Intra Nuclear Cascade |
0325 | d1st: | D | density\-weighted distance from first collision to the edge of the nucleus \(amount of material traversed / ρ0\) |
0326 | davg: | D | Average density\-weighted distance from all inelastic collisions to the edge of the nucleus |
0327 | pxf,pyf,pzf: | D | Fermi\-momentum of the struck nucleon \(or sum Fermi momentum for all inelastic nucleon participants for Ncolli>1\) in target rest frame with z along gamma\* direction |
0328 | Eexc: | D | Excitation energy in the nuclear remnant before evaporation and breakup\. |
0329 | RA | D | Nuclear PDF ratio for the up sea for the given event kinematics \(x,Q2\), but set to 1 if multi\-nucleon shadowing is off \(genShd=1\) |
0330 | User1,User2,User3: | D | User variables to prevent/delay future format changes |
0331 | nrTracks: | I | number of tracks in this event, including event history |
0332 {:.table-bordered}
0333 {:.table-striped}
0334
0335 * 4th line: <tt>============================================</tt>
0336 * 5th line: Information on track-wise variables stored in the file:
0337
0338 | I: | I | line index, runs from 1 to nrTracks |
0339 |----------------|---|--------------------------------------------------------------------------------------------------------------------------------------------|
0340 | ISTHKK\(I\): | I | status code KS: KS=1 is the only stable final state particle code, Use NoBAM variable \(below\) to specify origin of particle |
0341 | IDHKK\(I\): | I | particle KF code \(211: pion, 2112:n, \.\.\.\.\)\. Code 80000 refers to a nucleus, specified in more detail by A=IDRES\(I\), Z=IDXRES\(I\) |
0342 | JMOHKK\(2,I\): | I | line number of second mother particle |
0343 | JMOHKK\(1,I\): | I | line number of first mother particle |
0344 | JDAHKK\(1,I\): | I | normally the line number of the first daughter\. |
0345 | JDAHKK\(2,I\): | I | normally the line number of the last daughter\. |
0346 | PHKK\(1,I\): | D | px of particle \(GeV/c\) |
0347 | PHKK\(2,I\): | D | py of particle \(GeV/c\) |
0348 | PHKK\(3,I\): | D | pz of particle \(GeV/c\) |
0349 | PHKK\(4,I\): | D | Energy of particle \(GeV\) |
0350 | PHKK\(5,I\): | D | mass of particle \(GeV/c^2\) |
0351 | VHKK\(1,I\): | D | x vertex information \(mm\) |
0352 | VHKK\(2,I\): | D | y vertex information \(mm\) |
0353 | VHKK\(3,I\): | D | z vertex information \(mm\) |
0354 | IDRES\(I\): | I | Baryon number, or A for a nucleus \(IDHKK\(I\)=80000\), fractional B set to 0\. |
0355 | IDXRES\(I\): | I | Particle charge, \(Z for a nucleus\), 0 for fractional charge\. |
0356 | NOBAM\(I\): | I | Flag describing the particle origin, particularly for final state particles\. |
0357 {:.table-bordered}
0358 {:.table-striped}
0359
0360 * 6th line: <tt>============================================</tt>
0361 * 7th line: event information for first event. Format descriptor:
0362
0363 ```
0364 format ((I4,1x,$),(I10,1x,$),4(I4,1x,$),4(f12.6,1x,$),3(I4,1x,$),
0365 & I6,1x,$,f9.6,1x,$,I6,1x,$,2(f12.6,1x,$),7(f18.11,3x,$),
0366 & 11(f19.9,3x,$),4(f10.6,1x,$),9(I5,1x,$),2(f10.6,1x,$),
0367 & 3(f15.6,1x,$),2(f9.6,1x,$),3(e17.8,1x,$),I6,/)
0368 ```
0369 * 8th line: <tt>============================================</tt>
0370 * 9th to X-1 line: track-wise info of 1st event. Format descriptor:
0371
0372 ```
0373 format (2(I6,1X,$),I10,1x,$,4(I8,1x,$),5(f15.6,1x,$),3(e15.6,1x,$),3(I8,1x,$)/)
0374 ```
0375
0376 * Xth line <tt>============================================</tt>
0377
0378 **The information from line 7 to X repeats for each event.**
0379
0380 Something to be mentioned here is the first 4 tracks in every event which deliver the information of beam parameter are added externally in order to get some handy variables like z, ptVsGamma... So the mother daughter relationship of these four tracks can not be taken too seriously. But the orig number and daughter number of the tracks after those 4 tracks are consistent and can be used for further purposes.
0381
0382 The 4-momentum for particle I, PHKK(mu,I) is reported in the lab frame for all stable final state particles. It is also reported in the lab frame for most intermediate/document particles with the following exceptions: Particle 5 is a copy of the γ<sup>*</sup> with 4-momentum reported as zero. Particles 6 through A+5 are the incoming original nucleons from the A, in the target rest frame with γ<sup>*</sup> momentum along +z. The momentum corresponds to the Fermi momentum of the nucleon in question.
0383
0384 The impact parameter, defined as the transverse position of the virtual photon with respect to the nucleus center in a frame with z along γ<sup>*</sup>, is given by bx=VHKK(1,5) and by=VHKK(2,5) in mm.
0385
0386 The status codes ISTHKK(I) have the following meaning. Note that final state particles have status 1 (although internally -1 and 1001 are also used). All other statuses refer to intermediate particles or informational lines.
0387
0388 | \(\-1\): | Internally used for final state particle from excited nucleus evaporation and breakup\. Output as KS=1,NOBAM=3 |
0389 | 1: | stable final state particle, Note: internally, \-1 and 1001 are also used\. |
0390 | 2: | unstable intermediate particle |
0391 | 3: | Documentation line describing the collision |
0392 | 11: | Projectile \(γ\*\) documentation line |
0393 | 12: | Incoming wounded nucleon from nucleus |
0394 | 14: | Incoming spectator nucleon from nucleus |
0395 | 16: | Intermediate baryon involved in the intranuclear cascade |
0396 | 18: | Spectator nucleon \(wrt hard collision\) involved in the intranuclear cascade |
0397 | 19: | Intermediated meson involved in the intranuclear cascade |
0398 | 21: | documentation line describing the collision |
0399 | 1000: | excited nucleus, which will evaporate and breakup |
0400 | \(1001\): | Internally used to mean residual nucleus\. Output as KS=1, NOBAM=4 |
0401 {:.table-bordered}
0402 {:.table-striped}
0403
0404 <br />
0405 The NOBAM particle origin flag for final state particles has the following meaning:
0406
0407 | 0,2: | Created in the hard collision process\. |
0408 | 3: | Created during the evaporation/breakup phase \(formerly specified by KS=\-1\) |
0409 | 4: | Largest remnant nucleus created during the evaporation/breakup phase \(formerly specified by KS=1001\)\. |
0410 | 11\-34: | Particles created during the Intra\-nuclear cascade\. Cascade generation \(IDCH\) \#n specified by NOBAM=10\+n |
0411 {:.table-bordered}
0412 {:.table-striped}
0413
0414 <br />
0415 <br />
0416 <br />
0417 <br />
0418 <br />
0419 <br />
