source: trunk/source/processes/hadronic/models/chiral_inv_phase_space/cross_sections/src/G4QProtonNuclearCrossSection.cc @ 1340

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26//
27// The lust update: M.V. Kossov, CERN/ITEP(Moscow) 17-June-02
28// GEANT4 tag $Name: hadr-chips-V09-03-08 $
29//
30//
31// G4 Physics class: G4QProtonNuclearCrossSection for gamma+A cross sections
32// Created: M.V. Kossov, CERN/ITEP(Moscow), 20-Dec-03
33// The last update: M.V. Kossov, CERN/ITEP (Moscow) 15-Feb-04
34// --------------------------------------------------------------------------------
35// ****************************************************************************************
36// This Header is a part of the CHIPS physics package (author: M. Kosov)
37// ****************************************************************************************
38// Short description: CHIPS cross-sections for proton-nuclear interactions
39// -----------------------------------------------------------------------
40//
41//#define debug
42//#define pdebug
43//#define debug3
44//#define debugn
45//#define debugs
46
47#include "G4QProtonNuclearCrossSection.hh"
48
49// Initialization of the
50G4double* G4QProtonNuclearCrossSection::lastLEN=0; // Pointer to the lastArray of LowEn CS
51G4double* G4QProtonNuclearCrossSection::lastHEN=0; // Pointer to the lastArray of HighEn CS
52G4int     G4QProtonNuclearCrossSection::lastN=0;   // The last N of calculated nucleus
53G4int     G4QProtonNuclearCrossSection::lastZ=0;   // The last Z of calculated nucleus
54G4double  G4QProtonNuclearCrossSection::lastP=0.;  // Last used in cross section Momentum
55G4double  G4QProtonNuclearCrossSection::lastTH=0.; // Last threshold momentum
56G4double  G4QProtonNuclearCrossSection::lastCS=0.; // Last value of the Cross Section
57G4int     G4QProtonNuclearCrossSection::lastI=0;   // The last position in the DAMDB
58std::vector<G4double*>* G4QProtonNuclearCrossSection::LEN = new std::vector<G4double*>;
59std::vector<G4double*>* G4QProtonNuclearCrossSection::HEN = new std::vector<G4double*>;
60
61// Returns Pointer to the G4VQCrossSection class
62G4VQCrossSection* G4QProtonNuclearCrossSection::GetPointer()
63{
64  static G4QProtonNuclearCrossSection theCrossSection; //**Static body of Cross Section**
65  return &theCrossSection;
66}
67
68G4QProtonNuclearCrossSection::~G4QProtonNuclearCrossSection()
69{
70  G4int lens=LEN->size();
71  for(G4int i=0; i<lens; ++i) delete[] (*LEN)[i];
72  delete LEN;
73  G4int hens=HEN->size();
74  for(G4int i=0; i<hens; ++i) delete[] (*HEN)[i];
75  delete HEN;
76}
77
78// The main member function giving the collision cross section (P is in IU, CS is in mb)
79// Make pMom in independent units ! (Now it is MeV)
80G4double G4QProtonNuclearCrossSection::GetCrossSection(G4bool fCS, G4double pMom,
81                                                       G4int tgZ, G4int tgN, G4int PDG)
82{
83  static G4double tolerance=0.001;     // Tolerance (0.1%) to consider as "the same mom"
84  static G4int j;                      // A#0f Z/N-records already tested in AMDB
85  static std::vector <G4int>    colN;  // Vector of N for calculated nuclei (isotops)
86  static std::vector <G4int>    colZ;  // Vector of Z for calculated nuclei (isotops)
87  static std::vector <G4double> colP;  // Vector of last momenta for the reaction
88  static std::vector <G4double> colTH; // Vector of energy thresholds for the reaction
89  static std::vector <G4double> colCS; // Vector of last cross sections for the reaction
90  // ***---*** End of the mandatory Static Definitions of the Associative Memory ***---***
91#ifdef pebug
92  G4cout<<"G4QPrCS::GetCS:>>> f="<<fCS<<", p="<<pMom<<", Z="<<tgZ<<"("<<lastZ<<") ,N="<<tgN
93        <<"("<<lastN<<"),PDG=2212, thresh="<<lastTH<<",Sz="<<colN.size()<<G4endl;
94#endif
95  if(PDG!=2212) G4cout<<"-Warning-G4QProtonCS::GetCS:***Not a proton***,PDG="<<PDG<<G4endl;
96  G4bool in=false;                     // By default the isotope must be found in the AMDB
97  if(tgN!=lastN || tgZ!=lastZ)         // The nucleus was not the last used isotope
98  {
99    in      = false;                   // By default the isotope haven't been found in AMDB
100    lastP   = 0.;                      // New momentum history (nothing to compare with)
101    lastN   = tgN;                     // The last N of the calculated nucleus
102    lastZ   = tgZ;                     // The last Z of the calculated nucleus
103    lastI   = colN.size();             // Size of the Associative Memory DB in the heap
104    j  = 0;                            // A#0f records found in DB for this projectile
105#ifdef debug
106    G4cout<<"G4QPrCS::GetCS: the amount of records in the AMDB lastI="<<lastI<<G4endl;
107#endif
108    if(lastI) for(G4int i=0; i<lastI; i++) // AMDB exists, try to find the (Z,N) isotope
109    {
110      if(colN[i]==tgN && colZ[i]==tgZ) // Try the record "i" in the AMDB
111      {
112        lastI=i;                       // Remember the index for future fast/last use
113        lastTH =colTH[i];              // The last THreshold (A-dependent)
114#ifdef debug
115        G4cout<<"G4QPrCS::GetCS:*Found* P="<<pMom<<",Threshold="<<lastTH<<",j="<<j<<G4endl;
116#endif
117        if(pMom<=lastTH)
118        {
119#ifdef debug
120          G4cout<<"G4QPCS::GetCS:Found,P="<<pMom<<" < Threshold="<<lastTH<<",CS=0"<<G4endl;
121#endif
122          return 0.;                   // Energy is below the Threshold value
123        }
124        lastP  =colP [i];              // Last Momentum  (A-dependent)
125        lastCS =colCS[i];              // Last CrossSect (A-dependent)
126        if(std::fabs(lastP-pMom)<tolerance*pMom)
127        //if(lastP==pMom)              // VI do not use tolerance
128        {
129#ifdef pdebug
130          G4cout<<"..G4QPrCS::GetCS:.DoNothing.P="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
131#endif
132          //CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // Update param's only
133          return lastCS*millibarn;     // Use theLastCS
134        }
135        in = true;                     // This is the case when the isotop is found in DB
136        // Momentum pMom is in IU ! @@ Units
137#ifdef debug
138        G4cout<<"G4QPrCS::G:UpdatDB P="<<pMom<<",f="<<fCS<<",lI="<<lastI<<",j="<<j<<G4endl;
139#endif
140        lastCS=CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // read & update
141#ifdef debug
142        G4cout<<"G4QPrCS::GetCrosSec: *****> New (inDB) Calculated CS="<<lastCS<<G4endl;
143#endif
144        if(lastCS<=0. && pMom>lastTH)  // Correct the threshold (@@ No intermediate Zeros)
145        {
146#ifdef debug
147          G4cout<<"G4QPrCS::GetCS: New P="<<pMom<<"(CS=0) > Threshold="<<lastTH<<G4endl;
148#endif
149          lastCS=0.;
150          lastTH=pMom;
151        }
152        break;                         // Go out of the LOOP
153      }
154#ifdef debug
155      G4cout<<"-->G4QPrCrossSec::GetCrosSec: pPDG=2212, j="<<j<<", N="<<colN[i]
156            <<",Z["<<i<<"]="<<colZ[i]<<G4endl;
157#endif
158      j++;                             // Increment a#0f records found in DB
159    }
160#ifdef debug
161    G4cout<<"-?-G4QPrCS::GetCS:RC Z="<<tgZ<<",N="<<tgN<<",in="<<in<<",j="<<j<<" ?"<<G4endl;
162#endif
163    if(!in)                            // This isotope has not been calculated previously
164    {
165#ifdef debug
166      G4cout<<"^^^G4QPrCS::GetCS:CalcNew P="<<pMom<<", f="<<fCS<<", lastI="<<lastI<<G4endl;
167#endif
168      //!!The slave functions must provide cross-sections in millibarns (mb) !! (not in IU)
169      lastCS=CalculateCrossSection(fCS,0,j,2212,lastZ,lastN,pMom); //calculate & create
170      //if(lastCS>0.)                   // It means that the AMBD was initialized
171      //{
172
173        lastTH = ThresholdEnergy(tgZ, tgN); // The Threshold Energy which is now the last
174#ifdef debug
175        G4cout<<"G4QPrCrossSection::GetCrossSect: NewThresh="<<lastTH<<",P="<<pMom<<G4endl;
176#endif
177        colN.push_back(tgN);
178        colZ.push_back(tgZ);
179        colP.push_back(pMom);
180        colTH.push_back(lastTH);
181        colCS.push_back(lastCS);
182#ifdef debug
183        G4cout<<"G4QPrCS::GetCrosSec:recCS="<<lastCS<<",lZ="<<lastN<<",lN="<<lastZ<<G4endl;
184#endif
185        //} // M.K. Presence of H1 with high threshold breaks the syncronization
186#ifdef pdebug
187      G4cout<<"G4QPrCS::GetCS:1st,P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
188#endif
189      return lastCS*millibarn;
190    } // End of creation of the new set of parameters
191    else
192    {
193#ifdef debug
194      G4cout<<"G4QPrCS::GetCS: Update lastI="<<lastI<<",j="<<j<<G4endl;
195#endif
196      colP[lastI]=pMom;
197      colCS[lastI]=lastCS;
198    }
199  } // End of parameters udate
200  else if(pMom<=lastTH)
201  {
202#ifdef debug
203    G4cout<<"G4QPrCS::GetCS: Current P="<<pMom<<" < Threshold="<<lastTH<<", CS=0"<<G4endl;
204#endif
205    return 0.;                         // Momentum is below the Threshold Value -> CS=0
206  }
207  else if(std::fabs(lastP-pMom)<tolerance*pMom)
208  //else if(lastP==pMom)               // VI do not use tolerance
209  {
210#ifdef pdebug
211    G4cout<<"..G4QPCS::GetCS:OldNZ&P="<<lastP<<"="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
212#endif
213    return lastCS*millibarn;           // Use theLastCS
214  }
215  else                                 // It is the last used -> use the current tables
216  {
217#ifdef debug
218    G4cout<<"-!-G4QPCS::GetCS:UseCur P="<<pMom<<",f="<<fCS<<",I="<<lastI<<",j="<<j<<G4endl;
219#endif
220    lastCS=CalculateCrossSection(fCS,1,j,2212,lastZ,lastN,pMom); // Only read and UpdateDB
221    lastP=pMom;
222  }
223#ifdef debug
224  G4cout<<"==>G4QPrCS::GetCroSec: P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
225#endif
226  return lastCS*millibarn;
227}
228
229// The main member function giving the gamma-A cross section (E in GeV, CS in mb)
230G4double G4QProtonNuclearCrossSection::CalculateCrossSection(G4bool, G4int F, G4int I,
231                                        G4int, G4int targZ, G4int targN, G4double Momentum)
232{
233  static const G4double THmin=27.;     // default minimum Momentum (MeV/c) Threshold
234  static const G4double THmiG=THmin*.001; // minimum Momentum (GeV/c) Threshold
235  static const G4double dP=10.;        // step for the LEN (Low ENergy) table MeV/c
236  static const G4double dPG=dP*.001;   // step for the LEN (Low ENergy) table GeV/c
237  static const G4int    nL=105;        // A#of LEN points in E (step 10 MeV/c)
238  static const G4double Pmin=THmin+(nL-1)*dP; // minP for the HighE part with safety
239  static const G4double Pmax=227000.;  // maxP for the HEN (High ENergy) part 227 GeV
240  static const G4int    nH=224;        // A#of HEN points in lnE
241  static const G4double milP=std::log(Pmin);// Low logarithm energy for the HEN part
242  static const G4double malP=std::log(Pmax);// High logarithm energy (each 2.75 percent)
243  static const G4double dlP=(malP-milP)/(nH-1); // Step in log energy in the HEN part
244  static const G4double milPG=std::log(.001*Pmin);// Low logarithmEnergy for HEN part GeV/c
245#ifdef debug
246  G4cout<<"G4QProtNCS::CalCS:N="<<targN<<",Z="<<targZ<<",P="<<Momentum<<">"<<THmin<<G4endl;
247#endif
248  G4double sigma=0.;
249  if(F&&I) sigma=0.;                   // @@ *!* Fake line *!* to use F & I !!!Temporary!!!
250  G4double A=targN+targZ;              // A of the target
251#ifdef debug
252  G4cout<<"G4QProtNucCS::CalCS: A="<<A<<",F="<<F<<",I="<<I<<",nL="<<nL<<",nH="<<nH<<G4endl;
253#endif
254  if(F<=0)                             // This isotope was not the last used isotop
255  {
256    if(F<0)                            // This isotope was found in DAMDB =======> RETRIEVE
257    {
258      G4int sync=LEN->size();
259      if(sync<=I) G4cout<<"*!*G4QProtonNuclCS::CalcCrossSect:Sync="<<sync<<"<="<<I<<G4endl;
260      lastLEN=(*LEN)[I];               // Pointer to prepared LowEnergy cross sections
261      lastHEN=(*HEN)[I];               // Pointer to prepared High Energy cross sections
262    }
263    else                               // This isotope wasn't calculated before => CREATE
264    {
265      lastLEN = new G4double[nL];      // Allocate memory for the new LEN cross sections
266      lastHEN = new G4double[nH];      // Allocate memory for the new HEN cross sections
267      // --- Instead of making a separate function ---
268      G4double P=THmiG;                // Table threshold in GeV/c
269      for(G4int m=0; m<nL; m++)
270      {
271        lastLEN[m] = CrossSectionLin(targZ, targN, P);
272        P+=dPG;
273      }
274      G4double lP=milPG;
275      for(G4int n=0; n<nH; n++)
276      {
277        lastHEN[n] = CrossSectionLog(targZ, targN, lP);
278        lP+=dlP;
279      }
280#ifdef debug
281      G4cout<<"-*->G4QPr0tNucCS::CalcCS:Tab for Z="<<targZ<<",N="<<targN<<",I="<<I<<G4endl;
282#endif
283      // --- End of possible separate function
284      // *** The synchronization check ***
285      G4int sync=LEN->size();
286      if(sync!=I)
287      {
288        G4cout<<"***G4QProtonNuclCS::CalcCrossSect: Sinc="<<sync<<"#"<<I<<", Z=" <<targZ
289              <<", N="<<targN<<", F="<<F<<G4endl;
290        //G4Exception("G4ProtonNuclearCS::CalculateCS:","39",FatalException,"overflow DB");
291      }
292      LEN->push_back(lastLEN);          // remember the Low Energy Table
293      HEN->push_back(lastHEN);          // remember the High Energy Table
294    } // End of creation of the new set of parameters
295  } // End of parameters udate
296  // ============================== NOW the Magic Formula =================================
297#ifdef debug
298  G4cout<<"G4QPrNCS::CalcCS:lTH="<<lastTH<<",Pmi="<<Pmin<<",dP="<<dP<<",dlP="<<dlP<<G4endl;
299#endif
300  if (Momentum<lastTH) return 0.;      // It must be already checked in the interface class
301  else if (Momentum<Pmin)              // High Energy region
302  {
303#ifdef debug
304    G4cout<<"G4QPrNCS::CalcCS:bLEN A="<<A<<", nL="<<nL<<",TH="<<THmin<<",dP="<<dP<<G4endl;
305#endif
306    if(A<=1.) sigma=0.;
307    else      sigma=EquLinearFit(Momentum,nL,THmin,dP,lastLEN);
308#ifdef debugn
309    if(sigma<0.)
310      G4cout<<"G4QPrNuCS::CalcCS:A="<<A<<",E="<<Momentum<<",T="<<THmin<<",dP="<<dP<<G4endl;
311#endif
312  }
313  else if (Momentum<Pmax)              // High Energy region
314  {
315    G4double lP=std::log(Momentum);
316#ifdef debug
317    G4cout<<"G4QProtNucCS::CalcCS: before HEN nH="<<nH<<",iE="<<milP<<",dlP="<<dlP<<G4endl;
318#endif
319    sigma=EquLinearFit(lP,nH,milP,dlP,lastHEN);
320  }
321  else                                 // UHE region (calculation, not frequent)
322  {
323    G4double P=0.001*Momentum;         // Approximation formula is for P in GeV/c
324    sigma=CrossSectionFormula(targZ, targN, P, std::log(P));
325  }
326#ifdef debug
327  G4cout<<"G4QProtonNuclearCrossSection::CalcCS: CS="<<sigma<<G4endl;
328#endif
329  if(sigma<0.) return 0.;
330  return sigma;
331}
332
333// Electromagnetic momentum-threshold (in MeV/c)
334G4double G4QProtonNuclearCrossSection::ThresholdMomentum(G4int tZ, G4int tN)
335{
336  static const G4double third=1./3.;
337  static const G4double pM = G4QPDGCode(2212).GetMass(); // Projectile mass in MeV
338  static const G4double tpM= pM+pM;       // Doubled projectile mass (MeV)
339  G4double tA=tZ+tN;
340  if(tZ<.99 || tN<0.) return 0.;
341  else if(tZ==1 && tN==0) return 800.;    // A threshold on the free proton
342  //G4double dE=1.263*tZ/(1.+std::pow(tA,third));
343  G4double dE=tZ/(1.+std::pow(tA,third)); // Safety for diffused edge of the nucleus (QE)
344  G4double tM=931.5*tA;
345  G4double T=dE+dE*(dE/2+pM)/tM;
346  return std::sqrt(T*(tpM+T));
347}
348
349// Calculation formula for proton-nuclear inelastic cross-section (mb) (P in GeV/c)
350G4double G4QProtonNuclearCrossSection::CrossSectionLin(G4int tZ, G4int tN, G4double P)
351{
352  G4double sigma=0.;
353  if(P<ThresholdMomentum(tZ,tN)*.001) return sigma;
354  G4double lP=std::log(P);
355  if(tZ==1&&!tN){if(P>.35) sigma=CrossSectionFormula(tZ,tN,P,lP);}// s(pp)=0 below 350Mev/c
356  else if(tZ<97 && tN<152)                // General solution
357  {
358    G4double pex=0.;
359    G4double pos=0.;
360    G4double wid=1.;
361    if(tZ==13 && tN==14)                  // Excited metastable states
362    {
363      pex=230.;
364      pos=.13;
365      wid=8.e-5;
366    }
367    else if(tZ<7)
368    {
369      if(tZ==6 && tN==6)
370      {
371        pex=320.;
372        pos=.14;
373        wid=7.e-6;
374      }
375      else if(tZ==5 && tN==6)
376      {
377        pex=270.;
378        pos=.17;
379        wid=.002;
380      }
381      else if(tZ==4 && tN==5)
382      {
383        pex=600.;
384        pos=.132;
385        wid=.005;
386      }
387      else if(tZ==3 && tN==4)
388      {
389        pex=280.;
390        pos=.19;
391        wid=.0025;
392      }
393      else if(tZ==3 && tN==3)
394      {
395        pex=370.;
396        pos=.171;
397        wid=.006;
398      }
399      else if(tZ==2 && tN==1)
400      {
401        pex=30.;
402        pos=.22;
403        wid=.0005;
404      }
405    }
406    sigma=CrossSectionFormula(tZ,tN,P,lP);
407    if(pex>0.)
408    {
409      G4double dp=P-pos;
410      sigma+=pex*std::exp(-dp*dp/wid);
411    }
412  }
413  else
414  {
415    G4cerr<<"-Warning-G4QProtonNuclearCroSect::CSLin:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
416    sigma=0.;
417  }
418  if(sigma<0.) return 0.;
419  return sigma; 
420}
421
422// Calculation formula for proton-nuclear inelastic cross-section (mb) log(P in GeV/c)
423G4double G4QProtonNuclearCrossSection::CrossSectionLog(G4int tZ, G4int tN, G4double lP)
424{
425  G4double P=std::exp(lP);
426  return CrossSectionFormula(tZ, tN, P, lP);
427}
428// Calculation formula for proton-nuclear inelastic cross-section (mb) log(P in GeV/c)
429G4double G4QProtonNuclearCrossSection::CrossSectionFormula(G4int tZ, G4int tN,
430                                                           G4double P, G4double lP)
431{
432  G4double sigma=0.;
433  if(tZ==1 && !tN)                        // pp interaction (from G4QuasiElasticRatios)
434  {
435    G4double p2=P*P;
436    G4double lp=lP-3.5;
437    G4double lp2=lp*lp;
438    G4double rp2=1./p2;
439    G4double El=(.0557*lp2+6.72+30./P)/(1.+.49*rp2/P);
440    G4double To=(.3*lp2+38.2)/(1.+.54*rp2*rp2);
441    sigma=To-El;
442  }
443  else if(tZ<97 && tN<152)                // General solution
444  {
445    //G4double lP=std::log(P);            // Already calculated
446    G4double d=lP-4.2;
447    G4double p2=P*P;
448    G4double p4=p2*p2;
449    G4double a=tN+tZ;                       // A of the target
450    G4double al=std::log(a);
451    G4double sa=std::sqrt(a);
452    G4double a2=a*a;
453    G4double a2s=a2*sa;
454    G4double a4=a2*a2;
455    G4double a8=a4*a4;
456    G4double a12=a8*a4;
457    G4double a16=a8*a8;
458    G4double c=(170.+3600./a2s)/(1.+65./a2s);
459    G4double dl=al-3.;
460    G4double dl2=dl*dl;
461    G4double r=.21+.62*dl2/(1.+.5*dl2);
462    G4double g=40.*std::exp(al*0.712)/(1.+12.2/a)/(1.+34./a2);
463    G4double e=318.+a4/(1.+.0015*a4/std::exp(al*0.09))/(1.+4.e-28*a12)+
464               8.e-18/(1./a16+1.3e-20)/(1.+1.e-21*a12);
465    G4double s=3.57+.009*a2/(1.+.0001*a2*a);
466    G4double h=(.01/a4+2.5e-6/a)*(1.+6.e-6*a2*a)/(1.+6.e7/a12/a2);
467    sigma=(c+d*d)/(1.+r/p4)+(g+e*std::exp(-s*P))/(1.+h/p4/p4);
468#ifdef pdebug
469    G4cout<<"G4QProtNucCS::CSForm: A="<<a<<",P="<<P<<",CS="<<sigma<<",c="<<c<<",g="<<g
470          <<",d="<<d<<",r="<<r<<",e="<<e<<",h="<<h<<G4endl;
471#endif
472  }
473  else
474  {
475    G4cerr<<"-Warning-G4QProtonNuclearCroSect::CSForm:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
476    sigma=0.;
477  }
478  if(sigma<0.) return 0.;
479  return sigma; 
480}
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