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<img src='content_image/403920.jpg'>

while for the π − it will be the other way around. This will lead to an anti-alignment between pairs. In Fig. 17 we show two pairs which would fall into the above cuts. Both pairs are at the limit of the opening angle cut θ 1 and θ 2 equal 16 ◦ . The p t of the plus particle for pair number 1 is 1.14 GeV/c, while the minus particle is 1.39 GeV/c. Thus Δ P $^{t}$1 is equal to -0.25 GeV/c. The p t of the plus particle for pair number 2 is 1.31 GeV/c, the minus particle is 0.91 GeV/c and Δ P $^{t}$2 is equal to 0.40 GeV/c. Finally the mean value shown on Fig. 17 is the mid-point between the π + and the π − where one really uses the vector sum of the π + and the π − which moves this point toward the harder pion. 

Considering the above cuts we defined a correla- tion function where we combine pairs each having a 

Δ P t . Our variable is related to the sum of the abso- lute values of the individual Δ P t ’s ( | Δ P $^{t}$1 | + | Δ P $^{t}$2 | ). We assign a sign to this sum such that if the sign of the individual Δ P t ’s are the same it is a plus sign, while if they are different it is a minus sign. For the flux tube the color magnetic field extends over a large pseudorapidity range where quarks and anti- quarks rotate around the flux tube axis, therefore we want to sample pairs at the different sides of the tube making a separation in φ (Δ φ ) between 40 ◦ to 48 ◦ . We are interested in sampling the pairs on the other side so we require the separation in η (Δ η ) be 0.2 or less. For the numerator of the correlation function we consider all combinations of unique pairs (sign ( | Δ P $^{t}$1 | + | Δ P $^{t}$2 | )) from a given central Au Au event divided by a mixed event denominator created from 

