[904] | 1 | <!-- ******************************************************** --> |
---|
| 2 | <!-- --> |
---|
| 3 | <!-- [History] --> |
---|
| 4 | <!-- Changed by: Katsuya Amako, 21-Sep-1998 --> |
---|
| 5 | <!-- Proof read by: Joe Chuma, 29-Jun-1999 --> |
---|
| 6 | <!-- Changed by: Hisaya Kurashige, 28-Oct-2001 --> |
---|
| 7 | <!-- Changed by: Dennis Wright, 27-Nov-2001 --> |
---|
| 8 | <!-- Converted to DocBook: Katsuya Amako, Aug-2006 --> |
---|
| 9 | <!-- Changed by: Hisaya Kurashige, 02-Dec-2007 --> |
---|
| 10 | <!-- Changed by: Hisaya Kurashige, 01-Dec-2008 --> |
---|
| 11 | <!-- --> |
---|
| 12 | <!-- ******************************************************** --> |
---|
| 13 | |
---|
| 14 | |
---|
| 15 | <!-- ******************* Section (Level#1) ****************** --> |
---|
| 16 | <sect1 id="sect.Parti"> |
---|
| 17 | <title> |
---|
| 18 | Particles |
---|
| 19 | </title> |
---|
| 20 | |
---|
| 21 | |
---|
| 22 | <!-- ******************* Section (Level#2) ****************** --> |
---|
| 23 | <sect2 id="sect.Parti.Basic"> |
---|
| 24 | <title> |
---|
| 25 | Basic concepts |
---|
| 26 | </title> |
---|
| 27 | |
---|
| 28 | <para> |
---|
| 29 | There are three levels of classes to describe particles in Geant4. |
---|
| 30 | |
---|
| 31 | <variablelist> |
---|
| 32 | <varlistentry> |
---|
| 33 | <term> |
---|
| 34 | <emphasis>G4ParticleDefinition</emphasis> |
---|
| 35 | </term> |
---|
| 36 | <listitem> |
---|
| 37 | defines a particle |
---|
| 38 | </listitem> |
---|
| 39 | </varlistentry> |
---|
| 40 | <varlistentry> |
---|
| 41 | <term> |
---|
| 42 | <emphasis>G4DynamicParticle</emphasis> |
---|
| 43 | </term> |
---|
| 44 | <listitem> |
---|
| 45 | describes a particle interacting with materials |
---|
| 46 | </listitem> |
---|
| 47 | </varlistentry> |
---|
| 48 | <varlistentry> |
---|
| 49 | <term> |
---|
| 50 | <emphasis>G4Track</emphasis> |
---|
| 51 | </term> |
---|
| 52 | <listitem> |
---|
| 53 | describes a particle traveling in space and time |
---|
| 54 | </listitem> |
---|
| 55 | </varlistentry> |
---|
| 56 | </variablelist> |
---|
| 57 | </para> |
---|
| 58 | |
---|
| 59 | <para> |
---|
| 60 | <emphasis>G4ParticleDefinition</emphasis> aggregates information to |
---|
| 61 | characterize a particle's properties, such as name, mass, spin, |
---|
| 62 | life time, and decay modes. <emphasis>G4DynamicParticle</emphasis> aggregates |
---|
| 63 | information to describe the dynamics of particles, such as energy, |
---|
| 64 | momentum, polarization, and proper time, as well as ``particle |
---|
| 65 | definition'' information. <emphasis>G4Track</emphasis> includes all information |
---|
| 66 | necessary for tracking in a detector simulation, such as time, |
---|
| 67 | position, and step, as well as ``dynamic particle'' |
---|
| 68 | information. |
---|
| 69 | </para> |
---|
| 70 | |
---|
| 71 | <para> |
---|
| 72 | <emphasis>G4Track</emphasis> has all the information necessary for tracking in |
---|
| 73 | Geant4. It includes position, time, and step, as well as |
---|
| 74 | kinematics. Details of <emphasis>G4Track</emphasis> will be described in |
---|
| 75 | <xref linkend="sect.Track" />. |
---|
| 76 | </para> |
---|
| 77 | |
---|
| 78 | </sect2> |
---|
| 79 | |
---|
| 80 | |
---|
| 81 | <!-- ******************* Section (Level#2) ****************** --> |
---|
| 82 | <sect2 id="sect.Parti.Def"> |
---|
| 83 | <title> |
---|
| 84 | Definition of a particle |
---|
| 85 | </title> |
---|
| 86 | |
---|
| 87 | <para> |
---|
| 88 | There are a large number of elementary particles and nuclei. Geant4 |
---|
| 89 | provides the <emphasis>G4ParticleDefinition</emphasis> class to represent |
---|
| 90 | particles, and various particles, such as the electron, proton, and |
---|
| 91 | gamma have their own classes derived from |
---|
| 92 | <emphasis>G4ParticleDefinition</emphasis>. |
---|
| 93 | </para> |
---|
| 94 | |
---|
| 95 | <para> |
---|
| 96 | We do not need to make a class in Geant4 for every kind of |
---|
| 97 | particle in the world. There are more than 100 types of particles |
---|
| 98 | defined in Geant4 by default. Which particles should be included, |
---|
| 99 | and how to implement them, is determined according to the following |
---|
| 100 | criteria. (Of course, the user can define any particles he wants. |
---|
| 101 | Please see the <emphasis role="bold">User's Guide: For ToolKit |
---|
| 102 | Developers</emphasis>). |
---|
| 103 | </para> |
---|
| 104 | |
---|
| 105 | |
---|
| 106 | <!-- ******************* Section (Level#3) ****************** --> |
---|
| 107 | <sect3 id="sect.Parti.Def.PartiList"> |
---|
| 108 | <title> |
---|
| 109 | Particle List in Geant4 |
---|
| 110 | </title> |
---|
| 111 | |
---|
| 112 | <para> |
---|
| 113 | This list includes all particles in Geant4 and you can see |
---|
| 114 | properties of particles such as |
---|
| 115 | |
---|
| 116 | <itemizedlist spacing="compact"> |
---|
| 117 | <listitem><para> |
---|
| 118 | PDG encoding |
---|
| 119 | </para></listitem> |
---|
| 120 | <listitem><para> |
---|
| 121 | mass and width |
---|
| 122 | </para></listitem> |
---|
| 123 | <listitem><para> |
---|
| 124 | electric charge |
---|
| 125 | </para></listitem> |
---|
| 126 | <listitem><para> |
---|
| 127 | spin, isospin and parity |
---|
| 128 | </para></listitem> |
---|
| 129 | <listitem><para> |
---|
| 130 | magnetic moment |
---|
| 131 | </para></listitem> |
---|
| 132 | <listitem><para> |
---|
| 133 | quark contents |
---|
| 134 | </para></listitem> |
---|
| 135 | <listitem><para> |
---|
| 136 | life time and decay modes |
---|
| 137 | </para></listitem> |
---|
| 138 | </itemizedlist> |
---|
| 139 | </para> |
---|
| 140 | |
---|
| 141 | <para> |
---|
| 142 | Here is a list of particles in Geant4. This list is generated |
---|
| 143 | automatically by using Geant4 functionality, so listed values are |
---|
| 144 | same as those in your Geant4 application (as far as you do not |
---|
| 145 | change source codes). |
---|
| 146 | </para> |
---|
| 147 | |
---|
| 148 | <!-- ******* Bridgehead ******* --> |
---|
| 149 | <bridgehead renderas='sect4'> |
---|
| 150 | Categories |
---|
| 151 | </bridgehead> |
---|
| 152 | |
---|
| 153 | <para> |
---|
| 154 | <itemizedlist spacing="compact"> |
---|
| 155 | <listitem><para> |
---|
| 156 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/quarks/index.html"> |
---|
| 157 | gluon / quarks / di-quarks |
---|
| 158 | </ulink> |
---|
| 159 | </para></listitem> |
---|
| 160 | <listitem><para> |
---|
| 161 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/leptons/index.html"> |
---|
| 162 | leptons |
---|
| 163 | </ulink> |
---|
| 164 | </para></listitem> |
---|
| 165 | <listitem><para> |
---|
| 166 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/mesons/index.html"> |
---|
| 167 | mesons |
---|
| 168 | </ulink> |
---|
| 169 | </para></listitem> |
---|
| 170 | <listitem><para> |
---|
| 171 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/baryons/index.html"> |
---|
| 172 | baryons |
---|
| 173 | </ulink> |
---|
| 174 | </para></listitem> |
---|
| 175 | <listitem><para> |
---|
| 176 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/ions/index.html"> |
---|
| 177 | ions |
---|
| 178 | </ulink> |
---|
| 179 | </para></listitem> |
---|
| 180 | <listitem><para> |
---|
| 181 | <ulink url="./AllResources/TrackingAndPhysics/particleList.src/others/index.html"> |
---|
| 182 | others |
---|
| 183 | </ulink> |
---|
| 184 | </para></listitem> |
---|
| 185 | </itemizedlist> |
---|
| 186 | </para> |
---|
| 187 | |
---|
| 188 | </sect3> |
---|
| 189 | |
---|
| 190 | <!-- ******************* Section (Level#3) ****************** --> |
---|
| 191 | <sect3 id="sect.Parti.Def.Classif"> |
---|
| 192 | <title> |
---|
| 193 | Classification of particles |
---|
| 194 | </title> |
---|
| 195 | |
---|
| 196 | <para> |
---|
| 197 | <orderedlist spacing="compact"> |
---|
| 198 | <listitem><para> |
---|
| 199 | <para> |
---|
| 200 | elementary particles which should be tracked in Geant4 volumes |
---|
| 201 | </para> |
---|
| 202 | <para> |
---|
| 203 | All particles that can fly a finite length and interact with |
---|
| 204 | materials in detectors are included in this category. In addition, |
---|
| 205 | some particles with a very short lifetime are included |
---|
| 206 | for user's convenience. |
---|
| 207 | |
---|
| 208 | <orderedlist spacing="compact"> |
---|
| 209 | <listitem><para> |
---|
| 210 | stable particles |
---|
| 211 | <para> |
---|
| 212 | Stable means that the particle can not decay, or has a very small |
---|
| 213 | possibility to decay in detectors, e.g., gamma, electron, proton, |
---|
| 214 | and neutron. |
---|
| 215 | </para> |
---|
| 216 | </para></listitem> |
---|
| 217 | <listitem><para> |
---|
| 218 | long life (>10<superscript>-14</superscript>sec) particles |
---|
| 219 | <para> |
---|
| 220 | Particles which may travel a finite length, e.g., muon, charged |
---|
| 221 | pions. |
---|
| 222 | </para> |
---|
| 223 | </para></listitem> |
---|
| 224 | <listitem><para> |
---|
| 225 | short life particles that decay immediately in Geant4 |
---|
| 226 | <para> |
---|
| 227 | For example, pi<superscript>0</superscript>, eta |
---|
| 228 | </para> |
---|
| 229 | </para></listitem> |
---|
| 230 | <listitem><para> |
---|
| 231 | K<superscript>0</superscript> system |
---|
| 232 | <para> |
---|
| 233 | K<superscript>0</superscript> "decays" immediately into |
---|
| 234 | K<superscript>0</superscript><subscript>S</subscript> |
---|
| 235 | or K<superscript>0</superscript><subscript>L</subscript>, and then |
---|
| 236 | K<superscript>0</superscript><subscript>S</subscript>/ |
---|
| 237 | K<superscript>0</superscript><subscript>L</subscript> decays |
---|
| 238 | according to its life time and decay modes. |
---|
| 239 | </para> |
---|
| 240 | </para></listitem> |
---|
| 241 | <listitem><para> |
---|
| 242 | optical photon |
---|
| 243 | <para> |
---|
| 244 | Gamma and optical photon are distinguished in the simulation |
---|
| 245 | view, though both are the same particle (photons with different |
---|
| 246 | energies). For example, optical photon is used for Cerenkov light |
---|
| 247 | and scintillation light. |
---|
| 248 | </para> |
---|
| 249 | </para></listitem> |
---|
| 250 | <listitem><para> |
---|
| 251 | geantino/charged geantino |
---|
| 252 | <para> |
---|
| 253 | Geantino and charged geantino are virtual particles for |
---|
| 254 | simulation which do not interact with materials and undertake |
---|
| 255 | transportation processes only. |
---|
| 256 | </para> |
---|
| 257 | </para></listitem> |
---|
| 258 | </orderedlist> |
---|
| 259 | </para> |
---|
| 260 | </para></listitem> |
---|
| 261 | <listitem><para> |
---|
| 262 | nuclei |
---|
| 263 | <para> |
---|
| 264 | Any kinds of nucleus can be used in Geant4, such as alpha(He-4), |
---|
| 265 | uranium-238 and excited states of carbon-14. In addition, |
---|
| 266 | Geant4 provides hyper-nuclei. Nuclei in Geant4 are |
---|
| 267 | divided into two groups from the viewpoint of implementation. |
---|
| 268 | <orderedlist spacing="compact"> |
---|
| 269 | <listitem><para> |
---|
| 270 | light nuclei |
---|
| 271 | <para> |
---|
| 272 | Light nuclei frequently used in simulation, e.g., alpha, deuteron, |
---|
| 273 | He3, triton. |
---|
| 274 | </para> |
---|
| 275 | </para></listitem> |
---|
| 276 | <listitem><para> |
---|
| 277 | heavy nuclei (including hyper-nuclei) |
---|
| 278 | <para> |
---|
| 279 | Nuclei other than those defined in the previous category. |
---|
| 280 | </para> |
---|
| 281 | </para></listitem> |
---|
| 282 | </orderedlist> |
---|
| 283 | |
---|
| 284 | Note that G4ParticleDefinition represents nucleus state and |
---|
| 285 | G4DynamicParticle represents atomic state with some nucleus. Both |
---|
| 286 | alpha particle with charge of +2e and helium atom with no charge |
---|
| 287 | aggregates the same "particle definition" of G4Alpha, but different |
---|
| 288 | G4DynamicParticle objects should be assigned to them. (Details can |
---|
| 289 | be found below) |
---|
| 290 | </para> |
---|
| 291 | </para></listitem> |
---|
| 292 | <listitem><para> |
---|
| 293 | short-lived particles |
---|
| 294 | <para> |
---|
| 295 | Particles with very short life time decay immediately and are never |
---|
| 296 | tracked in the detector geometry. These particles are usually used |
---|
| 297 | only inside physics processes to implement some models of |
---|
| 298 | interactions. <emphasis>G4VShortLivedParticle</emphasis> is provided as |
---|
| 299 | the base class for these particles. All classes related to particles in |
---|
| 300 | this category can be found in <literal>shortlived</literal> sub-directory |
---|
| 301 | under the <literal>particles</literal> directory. |
---|
| 302 | |
---|
| 303 | <orderedlist spacing="compact"> |
---|
| 304 | <listitem><para> |
---|
| 305 | quarks/di-quarks |
---|
| 306 | <para> |
---|
| 307 | For example, all 6 quarks. |
---|
| 308 | </para> |
---|
| 309 | </para></listitem> |
---|
| 310 | <listitem><para> |
---|
| 311 | gluon |
---|
| 312 | </para></listitem> |
---|
| 313 | <listitem><para> |
---|
| 314 | baryon excited states with very short life |
---|
| 315 | <para> |
---|
| 316 | For example, spin 3/2 baryons and anti-baryons |
---|
| 317 | </para> |
---|
| 318 | </para></listitem> |
---|
| 319 | <listitem><para> |
---|
| 320 | meson excited states with very short life |
---|
| 321 | <para> |
---|
| 322 | For example, spin 1 vector bosons |
---|
| 323 | </para> |
---|
| 324 | </para></listitem> |
---|
| 325 | </orderedlist> |
---|
| 326 | </para> |
---|
| 327 | </para></listitem> |
---|
| 328 | </orderedlist> |
---|
| 329 | </para> |
---|
| 330 | |
---|
| 331 | </sect3> |
---|
| 332 | |
---|
| 333 | |
---|
| 334 | <!-- ******************* Section (Level#3) ****************** --> |
---|
| 335 | <sect3 id="sect.Parti.Def.Imple"> |
---|
| 336 | <title> |
---|
| 337 | Implementation of particles |
---|
| 338 | </title> |
---|
| 339 | |
---|
| 340 | <para> |
---|
| 341 | <emphasis>Single object created in the initialization :</emphasis> |
---|
| 342 | Categories a, b-1 |
---|
| 343 | </para> |
---|
| 344 | |
---|
| 345 | <para> |
---|
| 346 | These particles are frequently used for tracking in |
---|
| 347 | Geant4. An individual class is defined for each particle in these |
---|
| 348 | categories. The object in each class is unique. |
---|
| 349 | The user can get pointers to these objects by using static methods |
---|
| 350 | in their own classes. The unique object for each class is created |
---|
| 351 | when its static method is called in the ``initialization phase''. |
---|
| 352 | </para> |
---|
| 353 | |
---|
| 354 | <para> |
---|
| 355 | <emphasis>On-the-fly creation:</emphasis> Category b-2 |
---|
| 356 | </para> |
---|
| 357 | |
---|
| 358 | <para> |
---|
| 359 | Ions will travel in a detector geometry and should |
---|
| 360 | be tracked, however, the number of ions which may be used for |
---|
| 361 | hadronic processes is so huge that ions are dynamically |
---|
| 362 | created by requests from processes (and users). |
---|
| 363 | Each ion corresponds to one object of the <emphasis>G4Ions</emphasis> |
---|
| 364 | class. |
---|
| 365 | <emphasis>G4IonTable</emphasis> class is a dictionary for ions. |
---|
| 366 | <literal>G4ParticleTable::GetIon()</literal> method invokes |
---|
| 367 | <literal>G4IonTable::GetIon()</literal> method to create ions |
---|
| 368 | on the fly. |
---|
| 369 | </para> |
---|
| 370 | |
---|
| 371 | <para> |
---|
| 372 | Users can register a <emphasis>G4IsotopeTable</emphasis> to the |
---|
| 373 | <emphasis>G4IonTable</emphasis>. <emphasis>G4IsotopeTable</emphasis> |
---|
| 374 | describes properties of ions (exited energy, decay modes, life time |
---|
| 375 | and magnetic moments), which are used to create ions. |
---|
| 376 | </para> |
---|
| 377 | |
---|
| 378 | <para> |
---|
| 379 | Processes attached to heavy ions are same as those for |
---|
| 380 | <emphasis>G4GenericIon</emphasis> class. In other words, you need to |
---|
| 381 | create <emphasis>G4GenericIon</emphasis> and attach processes to it |
---|
| 382 | if you want to use heavy ions. |
---|
| 383 | </para> |
---|
| 384 | |
---|
| 385 | <para> |
---|
| 386 | <emphasis>G4ParticleGun</emphasis> can shoot any heavy ions |
---|
| 387 | with /gun/ions command after ``ion'' is selected by /gun/particle command. |
---|
| 388 | </para> |
---|
| 389 | |
---|
| 390 | <para> |
---|
| 391 | <emphasis>Dynamic creation by processes:</emphasis> Category c |
---|
| 392 | </para> |
---|
| 393 | |
---|
| 394 | <para> |
---|
| 395 | Particle types in this category are are not created |
---|
| 396 | by default, but will only be created by request from processes or |
---|
| 397 | directly by users. Each shortlived particle corresponds to one |
---|
| 398 | object of a class derived from <emphasis>G4VshortLivedParticle</emphasis>, |
---|
| 399 | and it will be created dynamically during the ``initialization |
---|
| 400 | phase''. |
---|
| 401 | </para> |
---|
| 402 | |
---|
| 403 | </sect3> |
---|
| 404 | |
---|
| 405 | |
---|
| 406 | <!-- ******************* Section (Level#3) ****************** --> |
---|
| 407 | <sect3 id="sect.Parti.Def.G4Parti"> |
---|
| 408 | <title> |
---|
| 409 | G4ParticleDefinition |
---|
| 410 | </title> |
---|
| 411 | |
---|
| 412 | <para> |
---|
| 413 | The <emphasis>G4ParticleDefinition</emphasis> class has ``read-only'' properties |
---|
| 414 | to characterize individual particles, such as name, mass, charge, |
---|
| 415 | spin, and so on. These properties are set during initialization of |
---|
| 416 | each particle. Methods to get these properties are listed in |
---|
| 417 | <xref linkend="table.Parti_1" />. |
---|
| 418 | |
---|
| 419 | <table id="table.Parti_1"> |
---|
| 420 | <title> |
---|
| 421 | Methods to get particle properties. |
---|
| 422 | </title> |
---|
| 423 | |
---|
| 424 | <tgroup cols="2"> |
---|
| 425 | <tbody> |
---|
| 426 | <row> |
---|
| 427 | <entry> |
---|
| 428 | <literal>G4String GetParticleName()</literal> |
---|
| 429 | </entry> |
---|
| 430 | <entry> |
---|
| 431 | particle name |
---|
| 432 | </entry> |
---|
| 433 | </row> |
---|
| 434 | <row> |
---|
| 435 | <entry> |
---|
| 436 | <literal>G4double GetPDGMass()</literal> |
---|
| 437 | </entry> |
---|
| 438 | <entry> |
---|
| 439 | mass |
---|
| 440 | </entry> |
---|
| 441 | </row> |
---|
| 442 | <row> |
---|
| 443 | <entry> |
---|
| 444 | <literal>G4double GetPDGWidth()</literal> |
---|
| 445 | </entry> |
---|
| 446 | <entry> |
---|
| 447 | decay width |
---|
| 448 | </entry> |
---|
| 449 | </row> |
---|
| 450 | <row> |
---|
| 451 | <entry> |
---|
| 452 | <literal>G4double GetPDGCharge()</literal> |
---|
| 453 | </entry> |
---|
| 454 | <entry> |
---|
| 455 | electric charge |
---|
| 456 | </entry> |
---|
| 457 | </row> |
---|
| 458 | <row> |
---|
| 459 | <entry> |
---|
| 460 | <literal>G4double GetPDGSpin()</literal> |
---|
| 461 | </entry> |
---|
| 462 | <entry> |
---|
| 463 | spin |
---|
| 464 | </entry> |
---|
| 465 | </row> |
---|
| 466 | <row> |
---|
| 467 | <entry> |
---|
| 468 | <literal>G4double GetPDGMagneticMoment()</literal> |
---|
| 469 | </entry> |
---|
| 470 | <entry> |
---|
| 471 | magnetic moment (0: not defined or no magnetic moment) |
---|
| 472 | </entry> |
---|
| 473 | </row> |
---|
| 474 | <row> |
---|
| 475 | <entry> |
---|
| 476 | <literal>G4int GetPDGiParity()</literal> |
---|
| 477 | </entry> |
---|
| 478 | <entry> |
---|
| 479 | parity (0:not defined) |
---|
| 480 | </entry> |
---|
| 481 | </row> |
---|
| 482 | <row> |
---|
| 483 | <entry> |
---|
| 484 | <literal>G4int GetPDGiConjugation()</literal> |
---|
| 485 | </entry> |
---|
| 486 | <entry> |
---|
| 487 | charge conjugation (0:not defined) |
---|
| 488 | </entry> |
---|
| 489 | </row> |
---|
| 490 | <row> |
---|
| 491 | <entry> |
---|
| 492 | <literal>G4double GetPDGIsospin()</literal> |
---|
| 493 | </entry> |
---|
| 494 | <entry> |
---|
| 495 | iso-spin |
---|
| 496 | </entry> |
---|
| 497 | </row> |
---|
| 498 | <row> |
---|
| 499 | <entry> |
---|
| 500 | <literal>G4double GetPDGIsospin3()</literal> |
---|
| 501 | </entry> |
---|
| 502 | <entry> |
---|
| 503 | 3<superscript>rd</superscript>-component of iso-spin |
---|
| 504 | </entry> |
---|
| 505 | </row> |
---|
| 506 | <row> |
---|
| 507 | <entry> |
---|
| 508 | <literal>G4int GetPDGiGParity()</literal> |
---|
| 509 | </entry> |
---|
| 510 | <entry> |
---|
| 511 | G-parity (0:not defined) |
---|
| 512 | </entry> |
---|
| 513 | </row> |
---|
| 514 | <row> |
---|
| 515 | <entry> |
---|
| 516 | <literal>G4String GetParticleType()</literal> |
---|
| 517 | </entry> |
---|
| 518 | <entry> |
---|
| 519 | particle type |
---|
| 520 | </entry> |
---|
| 521 | </row> |
---|
| 522 | <row> |
---|
| 523 | <entry> |
---|
| 524 | <literal>G4String GetParticleSubType()</literal> |
---|
| 525 | </entry> |
---|
| 526 | <entry> |
---|
| 527 | particle sub-type |
---|
| 528 | </entry> |
---|
| 529 | </row> |
---|
| 530 | <row> |
---|
| 531 | <entry> |
---|
| 532 | <literal>G4int GetLeptonNumber()</literal> |
---|
| 533 | </entry> |
---|
| 534 | <entry> |
---|
| 535 | lepton number |
---|
| 536 | </entry> |
---|
| 537 | </row> |
---|
| 538 | <row> |
---|
| 539 | <entry> |
---|
| 540 | <literal>G4int GetBaryonNumber()</literal> |
---|
| 541 | </entry> |
---|
| 542 | <entry> |
---|
| 543 | baryon number |
---|
| 544 | </entry> |
---|
| 545 | </row> |
---|
| 546 | <row> |
---|
| 547 | <entry> |
---|
| 548 | <literal>G4int GetPDGEncoding()</literal> |
---|
| 549 | </entry> |
---|
| 550 | <entry> |
---|
| 551 | particle encoding number by PDG |
---|
| 552 | </entry> |
---|
| 553 | </row> |
---|
| 554 | <row> |
---|
| 555 | <entry> |
---|
| 556 | <literal>G4int GetAntiPDGEncoding()</literal> |
---|
| 557 | </entry> |
---|
| 558 | <entry> |
---|
| 559 | encoding for anti-particle of this particle |
---|
| 560 | </entry> |
---|
| 561 | </row> |
---|
| 562 | </tbody> |
---|
| 563 | </tgroup> |
---|
| 564 | </table> |
---|
| 565 | </para> |
---|
| 566 | |
---|
| 567 | <para> |
---|
| 568 | <xref linkend="table.Parti_2" /> shows the methods of |
---|
| 569 | <emphasis>G4ParticleDefinition</emphasis> for |
---|
| 570 | getting information about decay modes and the life time of the |
---|
| 571 | particle. |
---|
| 572 | |
---|
| 573 | <table id="table.Parti_2"> |
---|
| 574 | <title> |
---|
| 575 | Methods to get particle decay modes and life time. |
---|
| 576 | </title> |
---|
| 577 | |
---|
| 578 | <tgroup cols="2"> |
---|
| 579 | <tbody> |
---|
| 580 | <row> |
---|
| 581 | <entry> |
---|
| 582 | <literal>G4bool GetPDGStable()</literal> |
---|
| 583 | </entry> |
---|
| 584 | <entry> |
---|
| 585 | stable flag |
---|
| 586 | </entry> |
---|
| 587 | </row> |
---|
| 588 | <row> |
---|
| 589 | <entry> |
---|
| 590 | <literal>G4double GetPDGLifeTime()</literal> |
---|
| 591 | </entry> |
---|
| 592 | <entry> |
---|
| 593 | life time |
---|
| 594 | </entry> |
---|
| 595 | </row> |
---|
| 596 | <row> |
---|
| 597 | <entry> |
---|
| 598 | <literal>G4DecayTable* GetDecayTable()</literal> |
---|
| 599 | </entry> |
---|
| 600 | <entry> |
---|
| 601 | decay table |
---|
| 602 | </entry> |
---|
| 603 | </row> |
---|
| 604 | </tbody> |
---|
| 605 | </tgroup> |
---|
| 606 | </table> |
---|
| 607 | </para> |
---|
| 608 | |
---|
| 609 | <para> |
---|
| 610 | Users can modify these properties, though the other properties |
---|
| 611 | listed above can not be change without rebuilding the |
---|
| 612 | libraries. |
---|
| 613 | </para> |
---|
| 614 | |
---|
| 615 | <para> |
---|
| 616 | Each particle has its own <emphasis>G4ProcessManger</emphasis> |
---|
| 617 | object that manages a list of processes applicable to the |
---|
| 618 | particle.(see <xref linkend="sect.HowToSpecPhysProc.ManagingProc"/> ) |
---|
| 619 | </para> |
---|
| 620 | |
---|
| 621 | |
---|
| 622 | </sect3> |
---|
| 623 | </sect2> |
---|
| 624 | |
---|
| 625 | |
---|
| 626 | <!-- ******************* Section (Level#2) ****************** --> |
---|
| 627 | <sect2 id="sect.Parti.Dynam"> |
---|
| 628 | <title> |
---|
| 629 | Dynamic particle |
---|
| 630 | </title> |
---|
| 631 | |
---|
| 632 | <para> |
---|
| 633 | The <emphasis>G4DynamicParticle</emphasis> class has kinematics information for |
---|
| 634 | the particle and is used for describing the dynamics of physics |
---|
| 635 | processes. The properties in <emphasis>G4DynamicParticle</emphasis> are listed in |
---|
| 636 | <xref linkend="table.Parti_4" />. |
---|
| 637 | |
---|
| 638 | <table id="table.Parti_4"> |
---|
| 639 | <title> |
---|
| 640 | Methods to set/get cut off values. |
---|
| 641 | </title> |
---|
| 642 | |
---|
| 643 | <tgroup cols="2"> |
---|
| 644 | <tbody> |
---|
| 645 | <row> |
---|
| 646 | <entry> |
---|
| 647 | <literal>G4double theDynamicalMass</literal> |
---|
| 648 | </entry> |
---|
| 649 | <entry> |
---|
| 650 | dynamical mass |
---|
| 651 | </entry> |
---|
| 652 | </row> |
---|
| 653 | <row> |
---|
| 654 | <entry> |
---|
| 655 | <literal>G4ThreeVector theMomentumDirection</literal> |
---|
| 656 | </entry> |
---|
| 657 | <entry> |
---|
| 658 | normalized momentum vector |
---|
| 659 | </entry> |
---|
| 660 | </row> |
---|
| 661 | <row> |
---|
| 662 | <entry> |
---|
| 663 | <literal>G4ParticleDefinition* theParticleDefinition</literal> |
---|
| 664 | </entry> |
---|
| 665 | <entry> |
---|
| 666 | definition of particle |
---|
| 667 | </entry> |
---|
| 668 | </row> |
---|
| 669 | <row> |
---|
| 670 | <entry> |
---|
| 671 | <literal>G4double theDynamicalSpin</literal> |
---|
| 672 | </entry> |
---|
| 673 | <entry> |
---|
| 674 | dynamical spin |
---|
| 675 | (i.e. total angular momentum as a ion/atom ) |
---|
| 676 | </entry> |
---|
| 677 | </row> |
---|
| 678 | <row> |
---|
| 679 | <entry> |
---|
| 680 | <literal>G4ThreeVector thePolarization</literal> |
---|
| 681 | </entry> |
---|
| 682 | <entry> |
---|
| 683 | polarization vector |
---|
| 684 | </entry> |
---|
| 685 | </row> |
---|
| 686 | <row> |
---|
| 687 | <entry> |
---|
| 688 | <literal>G4double theMagneticMoment</literal> |
---|
| 689 | </entry> |
---|
| 690 | <entry> |
---|
| 691 | dynamical magnetic moment |
---|
| 692 | (i.e. total magnetic moment as a ion/atom ) |
---|
| 693 | </entry> |
---|
| 694 | </row> |
---|
| 695 | <row> |
---|
| 696 | <entry> |
---|
| 697 | <literal>G4double theKineticEnergy</literal> |
---|
| 698 | </entry> |
---|
| 699 | <entry> |
---|
| 700 | kinetic energy |
---|
| 701 | </entry> |
---|
| 702 | </row> |
---|
| 703 | <row> |
---|
| 704 | <entry> |
---|
| 705 | <literal>G4double theProperTime</literal> |
---|
| 706 | </entry> |
---|
| 707 | <entry> |
---|
| 708 | proper time |
---|
| 709 | </entry> |
---|
| 710 | </row> |
---|
| 711 | <row> |
---|
| 712 | <entry> |
---|
| 713 | <literal>G4double theDynamicalCharge</literal> |
---|
| 714 | </entry> |
---|
| 715 | <entry> |
---|
| 716 | dynamical electric charge |
---|
| 717 | (i.e. total electric charge as a ion/atom ) |
---|
| 718 | </entry> |
---|
| 719 | </row> |
---|
| 720 | <row> |
---|
| 721 | <entry> |
---|
| 722 | <literal>G4ElectronOccupancy* theElectronOccupancy</literal> |
---|
| 723 | </entry> |
---|
| 724 | <entry> |
---|
| 725 | electron orbits for ions |
---|
| 726 | </entry> |
---|
| 727 | </row> |
---|
| 728 | </tbody> |
---|
| 729 | </tgroup> |
---|
| 730 | </table> |
---|
| 731 | </para> |
---|
| 732 | |
---|
| 733 | <para> |
---|
| 734 | Here, the dynamical mass is defined as the mass for the dynamic |
---|
| 735 | particle. For most cases, it is same as the mass defined in |
---|
| 736 | <emphasis>G4ParticleDefinition</emphasis> class ( i.e. mass value given by |
---|
| 737 | <literal>GetPDGMass()</literal> method). However, there are two |
---|
| 738 | exceptions. |
---|
| 739 | |
---|
| 740 | <itemizedlist spacing="compact"> |
---|
| 741 | <listitem><para> |
---|
| 742 | resonance particle |
---|
| 743 | </para></listitem> |
---|
| 744 | <listitem><para> |
---|
| 745 | ions |
---|
| 746 | </para></listitem> |
---|
| 747 | </itemizedlist> |
---|
| 748 | </para> |
---|
| 749 | |
---|
| 750 | <para> |
---|
| 751 | Resonance particles have large mass width and the total energy of |
---|
| 752 | decay products at the center of mass system can be different event |
---|
| 753 | by event. |
---|
| 754 | </para> |
---|
| 755 | |
---|
| 756 | <para> |
---|
| 757 | As for ions, <emphasis>G4ParticleDefintion</emphasis> defines a nucleus and |
---|
| 758 | <emphasis>G4DynamicParticle</emphasis> defines an atom. |
---|
| 759 | <emphasis>G4ElectronOccupancy</emphasis> describes state of orbital electrons. |
---|
| 760 | So, the dynamic mass can be different from the PDG mass by the mass |
---|
| 761 | of electrons (and their binding energy). In addition, the dynamical |
---|
| 762 | charge, spin and magnetic moment are those of the atom/ion |
---|
| 763 | (i.e. including nucleus and orbit electrons). |
---|
| 764 | </para> |
---|
| 765 | |
---|
| 766 | <para> |
---|
| 767 | Decay products of heavy flavor particles are given in many event |
---|
| 768 | generators. In such cases, <emphasis>G4VPrimaryGenerator</emphasis> sets this |
---|
| 769 | information in <literal>*thePreAssignedDecayProducts</literal>. In addition, |
---|
| 770 | decay time of the particle can be set arbitrarily time by using |
---|
| 771 | <literal>PreAssignedDecayProperTime</literal>. |
---|
| 772 | </para> |
---|
| 773 | |
---|
| 774 | |
---|
| 775 | </sect2> |
---|
| 776 | </sect1> |
---|