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UPDATED Chemical Freeze-out for Cu+Cu 22.4 GeV and Au+Au 19.6 GeV

Updated on Wed, 2011-09-21 01:47. Originally created by omall on 2011-09-21 01:45.

The model applied in the previous study was a basic model that didn't account for resonance decays which the ratios used have not been corrected for.  This has drastically affected the freeze-out temperature and slightly affected the baryon chemical potential.

This model also uses the pi-/pi+ ratio rather than pi+/pi- ratio of the previous model.  No noticable changes were seen due to this.

Datapoints and statistical errors are taken from the fit to the low-chi-squared values with low-chi-squared-stat-err of the ratios
Systematic Erros are taken from the fit to the low-chi-sqaured values with systematic-errors on the ratios in conjunction with alternating the ratios by the systematic-erros.

Values for the Cu 0-5% central and Au0-10% central are the same as lokesh's look at the data.

Here are the final values Tch and muB:

Cu CuCu 0-5% CuCu 5-10% CuCu 10-20% CuCu 20-30% CuCu 30-40% CuCu 40-50% CuCu 50-70%
Tch 160.283 160.931 162.071 162.053 160.185 159.044 157.744
Tche 5.430 4.897 4.748 4.479 3.891 3.618 4.272
muB 138.884 139.626 136.210 130.635 126.831 126.601 116.683
muBe 8.350 7.727 7.455 7.191 6.632 6.733 6.743
               
Au AuAu 0-10% AuAu 10-30% AuAu 30-50%        
Tch 157.170 159.113 156.036        
Tche 8.321 7.071 6.180        
muB 186.951 179.917 166.181        
muBe 19.378 17.059 15.598        

 

Here are the fits with staterr, syserr, toterr, and avg-values with avg-error.  All are consistent with each other.

  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 0-5% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 160.283 1.474 160.289 3.856 160.281 4.113 163.415 1.545
muq 46.295 0.980 46.294 2.412 46.294 2.603 46.759 1.002
mus 12.659 3.145 12.614 9.374 12.656 9.801 11.780 3.121
gammas 0.676 0.024 0.676 0.070 0.676 0.074 0.688 0.025
Chisq 1.906   0.184   0.167   1.796  
muB 138.884 2.941 138.881 7.237 138.883 7.809 140.278 3.005
muS 33.635 3.294 33.680 9.680 33.638 10.141 34.980 3.278
Tch Diffs     0.00679   0.001342   3.132752  
muB Diffs     0.003069   0.001065   1.393695  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 5-10% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 160.931 1.698 160.932 3.215 160.933 3.684 163.781 1.771
muq 46.542 1.100 46.544 2.055 46.549 2.342 47.212 1.108
mus 14.572 3.167 14.551 9.676 14.547 10.181 13.824 3.181
gammas 0.684 0.025 0.684 0.073 0.684 0.077 0.696 0.025
Chisq 1.730   0.126   0.117   1.653  
muB 139.626 3.299 139.632 6.166 139.648 7.026 141.637 3.325
muS 31.970 3.353 31.993 9.892 32.002 10.447 33.388 3.368
Tch Diffs     0.00119   0.002456   2.85028  
muB Diffs     0.005949   0.021537   2.010303  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 10-20% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 162.071 1.399 162.071 3.333 162.070 3.787 164.688 1.566
muq 45.403 0.865 45.403 2.065 45.401 2.279 46.045 0.934
mus 13.077 2.882 13.059 9.605 13.051 10.068 12.571 3.001
gammas 0.669 0.022 0.670 0.072 0.669 0.075 0.681 0.022
Chisq 2.492   0.121   0.115   2.419  
muB 136.210 2.595 136.208 6.195 136.204 6.837 138.135 2.802
muS 32.327 3.009 32.344 9.825 32.350 10.323 33.474 3.143
Tch Diffs     0.000427   0.001297   2.616577  
muB Diffs     0.002301   0.006054   1.924689  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 20-30% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 162.053 1.606 162.051 3.197 162.050 3.459 164.203 1.615
muq 43.545 0.990 43.545 1.925 43.546 2.140 44.102 0.966
mus 11.234 2.941 11.231 10.089 11.195 10.490 10.704 2.918
gammas 0.649 0.022 0.649 0.073 0.649 0.076 0.660 0.021
Chisq 0.547   0.032   0.030   0.634  
muB 130.635 2.970 130.636 5.775 130.638 6.419 132.305 2.897
muS 32.311 3.103 32.315 10.271 32.350 10.706 33.398 3.073
Tch Diffs     0.001282   0.003128   2.150299  
muB Diffs     0.000984   0.002211   1.669968  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 30-40% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 160.185 1.771 160.189 2.620 160.189 3.091 161.767 1.782
muq 42.277 1.133 42.280 1.621 42.278 1.970 42.753 1.126
mus 10.799 3.719 10.792 8.975 10.784 9.609 9.597 3.662
gammas 0.607 0.026 0.607 0.061 0.607 0.065 0.620 0.026
Chisq 3.593   0.259   0.241   2.864  
muB 126.831 3.398 126.840 4.863 126.835 5.911 128.258 3.377
muS 31.478 3.887 31.488 9.120 31.495 9.809 33.156 3.831
Tch Diffs     0.004684   0.004486   1.582061  
muB Diffs     0.008775   0.003696   1.427523  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 40-50% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 159.044 2.066 159.045 2.406 159.044 3.250 159.671 2.229
muq 42.200 1.365 42.202 1.546 42.201 2.097 42.383 1.443
mus 14.065 3.713 14.062 9.298 14.061 10.023 13.714 3.835
gammas 0.579 0.024 0.579 0.061 0.579 0.065 0.592 0.026
Chisq 0.381   0.036   0.033   0.509  
muB 126.601 4.094 126.607 4.639 126.604 6.291 127.148 4.329
muS 28.135 3.956 28.140 9.425 28.141 10.240 28.668 4.098
Tch Diffs     0.001465   0.000641   0.62764  
muB Diffs     0.006477   0.003696   0.547326  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
CuCu 50-70% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 157.744 2.043 157.745 2.933 157.742 3.573 159.427 2.206
muq 38.894 1.390 38.892 1.484 38.887 2.011 39.303 1.405
mus 8.085 3.970 8.069 9.145 8.110 9.958 8.756 4.005
gammas 0.527 0.024 0.527 0.059 0.527 0.064 0.550 0.024
Chisq 0.252   0.008   0.008   0.286  
muB 116.683 4.171 116.676 4.451 116.660 6.033 117.908 4.214
muS 30.810 4.206 30.823 9.264 30.777 10.159 30.546 4.245
Tch Diffs     0.000702   0.002105   1.683136  
muB Diffs     0.006696   0.022671   1.22517  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
AuAu 0-10% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 157.170 2.302 157.174 7.564 157.179 7.687 156.164 2.341
muq 62.317 1.639 62.324 5.917 62.328 6.006 61.979 1.720
mus 15.519 3.026 15.582 12.797 15.536 12.875 16.330 3.064
gammas 0.838 0.028 0.837 0.111 0.838 0.112 0.833 0.029
Chisq 43.095   2.078   1.984   38.976  
muB 186.951 4.916 186.972 17.751 186.985 18.018 185.938 5.159
muS 46.798 3.442 46.742 14.099 46.792 14.207 45.649 3.514
Tch Diffs     0.003967   0.008743   1.006318  
muB Diffs     0.021081   0.033933   1.012551  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
AuAu 10-30% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 159.113 2.481 159.126 6.171 159.103 6.526 158.918 2.650
muq 59.972 2.040 60.005 4.898 59.987 5.263 59.451 2.198
mus 21.648 2.605 21.671 11.063 21.615 11.399 20.605 2.666
gammas 0.747 0.021 0.747 0.088 0.747 0.091 0.755 0.022
Chisq 24.634   1.007   0.965   24.040  
muB 179.917 6.120 180.016 14.694 179.961 15.788 178.352 6.594
muS 38.325 3.308 38.334 12.099 38.372 12.555 38.846 3.455
Tch Diffs     0.013321   0.009888   0.195374  
muB Diffs     0.099255   0.044289   1.565208  
                 
  Ratios: Erros: Ratios: Erros: Ratios: Erros: Ratios: Erros:
AuAu 30-50% lowchisq lowchisq-stat lowchisq sys lowchisq tot avg avg-stat
  Value Error            
Tch 156.036 2.705 156.042 4.981 156.044 5.578 156.621 2.746
muq 55.394 2.351 55.398 4.194 55.406 4.734 55.325 2.397
mus 15.491 3.130 15.482 9.472 15.478 9.867 14.664 3.124
gammas 0.704 0.024 0.704 0.073 0.704 0.076 0.719 0.025
Chisq 17.501   0.739   0.708   15.092  
muB 166.181 7.053 166.195 12.583 166.219 14.203 165.974 7.190
muS 39.903 3.914 39.916 10.359 39.928 10.944 40.661 3.937
Tch Diffs     0.005936   0.008377   0.584717  
muB Diffs     0.01419   0.038418   0.206475  

 

 

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