@@ -73,8 +73,6 @@ class GeneratorHGPythia8 : public GeneratorPythia8
7373 void setSigmaHard (double sigma ) { mSigmaHardIn = sigma ; }
7474 /// Soft NN cross-section in mb
7575 void setSigmaSoft (double sigma ) { mSigmaSoft = sigma ; }
76- /// Impact-parameter dependent shadowing of the hard cross-section
77- void setShadowing (bool val ) { mShadowing = val ; }
7876 /// Include elastic NN scattering in the eikonal
7977 void setElastic (bool val ) { mElastic = val ; }
8078
@@ -128,8 +126,7 @@ class GeneratorHGPythia8 : public GeneratorPythia8
128126
129127 LOG (info ) << "GeneratorHGPythia8 : A = " << mA << " , B = " << mB << " , sqrt (s_NN ) = " << energy
130128 << " GeV, sigma_hard = " << mSigmaHard << " mb, sigma_soft = " << mSigmaSoft
131- << " mb, b in [" << mBMin << ", " << mBMax << "] fm, shadowing " << mShadowing
132- << ", elastic " << mElastic ;
129+ << " mb, b in [" << mBMin << ", " << mBMax << "] fm, elastic " << mElastic ;
133130 return true ;
134131 }
135132
@@ -212,13 +209,6 @@ class GeneratorHGPythia8 : public GeneratorPythia8
212209 /// Hard cross-section (pT > 2 GeV) in mb as a function of sqrt(s_NN), from the reference implementation
213210 double sigmaHardFromTable (double energy ) const
214211 {
215- if (mShadowing ) {
216- if (energy < 201 ) return 7.71968269 ;
217- if (energy < 2800 ) return 39.5451393 ;
218- if (energy < 5100 ) return 54.2068253 ;
219- if (energy < 8100 ) return 69.7713470 ;
220- return -1 ;
221- }
222212 if (energy < 20 ) return 0.161440969 ;
223213 if (energy < 40 ) return 1.07414019 ;
224214 if (energy < 64 ) return 2.32993174 ;
@@ -228,6 +218,7 @@ class GeneratorHGPythia8 : public GeneratorPythia8
228218 if (energy < 5500 ) return 130.82 ;
229219 if (energy < 6400 ) return 144.17 ;
230220 if (energy < 8100 ) return 166.184998 ;
221+ if (energy < 9700 ) return 180.87 ;
231222 return -1 ;
232223 }
233224
@@ -323,11 +314,7 @@ class GeneratorHGPythia8 : public GeneratorPythia8
323314 std ::fill (mWounded [j ].begin (), mWounded [j ].end (), 0 );
324315 std ::fill (mWoundedBlackDisc [j ].begin (), mWoundedBlackDisc [j ].end (), 0 );
325316 }
326- // shadowing of the hard cross-section depends on b only
327- const double rrb = TMath ::Min (1. , b * b / 35.2 / 1.44 );
328- const double aphx = 0.1 * 4. / 3. * 4.92 * TMath ::Sqrt (1. - rrb );
329- const double sigHS = mShadowing ? mSigmaHard - aphx * 103.65 : mSigmaHard ;
330- const double gstot0 = mElastic ? 2. * (1. - TMath ::Exp (- (mSigmaSoft + sigHS ) / mSigmaSoft * eikonal (0.001 ))) : 1. ;
317+ const double gstot0 = mElastic ? 2. * (1. - TMath ::Exp (- (mSigmaSoft + mSigmaHard ) / mSigmaSoft * eikonal (0.001 ))) : 1. ;
331318
332319 mImpactParameter = b ;
333320 mNcoll = mNcollHard = mNhard = mNcollBlackDisc = 0 ;
@@ -348,7 +335,7 @@ class GeneratorHGPythia8 : public GeneratorPythia8
348335 r2 /= b02 ;
349336 r2 /= gstot0 ;
350337 const double chi = eikonal (TMath ::Sqrt (r2 ));
351- const double gs = 1. - TMath ::Exp (-2. * (mSigmaSoft + sigHS ) / mSigmaSoft * chi );
338+ const double gs = 1. - TMath ::Exp (-2. * (mSigmaSoft + mSigmaHard ) / mSigmaSoft * chi );
352339 const double gstot = 2. * (1. - TMath ::Sqrt (1. - gs ));
353340 const double rantot = mRandom -> Rndm () * gstot0 ;
354341 if (rantot > gstot && mElastic ) {
@@ -361,7 +348,7 @@ class GeneratorHGPythia8 : public GeneratorPythia8
361348 mWounded [1 ][j ] = 1 ;
362349 mNcoll ++ ;
363350 // minijets
364- const double tt = 2. * chi * sigHS / mSigmaSoft ;
351+ const double tt = 2. * chi * mSigmaHard / mSigmaSoft ;
365352 const double ts = 2. * chi ;
366353 if (rantot < TMath ::Exp (- tt ) * (1. - TMath ::Exp (- ts ))) {
367354 nMPI [0 ]++ ;
@@ -416,7 +403,6 @@ class GeneratorHGPythia8 : public GeneratorPythia8
416403 double mSigmaHardIn = -1. ;
417404 double mSigmaHard = -1. ;
418405 double mSigmaSoft = 57. ;
419- bool mShadowing = false;
420406 bool mElastic = false;
421407
422408 // Glauber state
@@ -448,13 +434,12 @@ class GeneratorHGPythia8 : public GeneratorPythia8
448434/// sigmaHard < 0: hard cross-section from the built-in sqrt(s_NN) table (up to 8.1 TeV).
449435FairGenerator * generateHGPythia8 (int A = 208 , int B = 208 , double bMin = 0. , double bMax = -1. ,
450436 double sigmaHard = -1. , double sigmaSoft = 57. ,
451- bool shadowing = false, bool elastic = false)
437+ bool elastic = false)
452438{
453439 auto gen = new o2 ::eventgen ::GeneratorHGPythia8 (A , B );
454440 gen -> setImpactParameterRange (bMin , bMax );
455441 gen -> setSigmaHard (sigmaHard );
456442 gen -> setSigmaSoft (sigmaSoft );
457- gen -> setShadowing (shadowing );
458443 gen -> setElastic (elastic );
459444 return gen ;
460445}
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