text: where the sum refers to spins belonging to NN layers 
  i and j, respectively, while Qz is the bulk helical pitch 
  vector along the z direction. The second possibility is 
  that of looking at the integral of the structure factor: 
  
  where β = 1/kBT , and o is one of the relevant observ- 
  ables, i.e. ml, M, κ, MHM . In this paper, we shall mainly 
  locate the critical temperature by looking at the intersec- 
  tion of the graphs of the Binder cumulant25, Eq. (9), as a 
  function of T obtained at diﬀerent L. For clarity reasons, 
  we introduce also the following symbols: by TN (n) we 
  will denote the helical/fan phase transition temperature 
  for thickness n, TC(n) will instead indicate the order- 
  ing temperature of the sample as deduced by looking at 
  the behaviour of the average order parameter (3), while 
  T l 
  C(n) will be the l-th plane transition temperature re- 
  lated to the order parameter deﬁned in Eq. (2). 
  
  π 
  
  1 
  K Z 
  0 
  MHM =  dqzS(~q)  (5) 