13  w_0 scale setting

The fit antsaz: \left(\frac{w_0}{a}\right)_{lat}=\frac{w_0^{iso}}{a}\left[1+P[5](\xi-\xi^{iso})\right] with \xi=\frac{M_\pi^2}{(4\pi f_\pi)^2}, and the chiral LO from (Bär and Golterman 2014, eq (4.8)).

13.1 iter 0

\chi^2/dof= 3.61635

par a_from_w0 a_from_fpi
a(A) 0.094475(93) 0.09022(64)
a(B) 0.080892(26) 0.079507(47)
a(C) 0.068757(38) 0.068187(66)
a(D) 0.057125(34) 0.056858(76)
a(E) 0.049148(38) 0.048919(65)
P[5] 0.574(24) 0

<r >

13.2 with corrections

\chi^2/dof= 1.58581

par a_from_w0 a_from_fpi
a(A) 0.09420(12) 0.09022(64)
a(B) 0.08117(10) 0.079614(53)
a(C) 0.06890(10) 0.068143(67)
a(D) 0.05751(13) 0.056936(78)
a(E) 0.049078(61) 0.048930(64)
P[5] 0.663(31) 0

adding a2*xi

\chi^2/dof= 0.253175

par a_from_w0 a_from_fpi
a(A) 0.09390(18) 0.09022(64)
a(B) 0.08129(11) 0.079614(53)
a(C) 0.06891(10) 0.068143(67)
a(D) 0.05754(13) 0.056936(78)
a(E) 0.049086(62) 0.048930(64)
P[5] -0.20(24) 0
P[6] -217(64) 0

<r >

14 comparing w0 before and after corrections

<r >

14.1 w0 using a from fpi (corrections included)

P[0] represent w_0 at the physical point. BMW value shoul be 0.17236

\chi^2/dof= 3.10512

P value
P[0] 0.1696(20)
P[1] 0.659(35)
P[2] 8.0(6.4)
P[3] -1371(720)

<r >

14.2 fit the difference (corrections included)

\chi^2/dof= 2.30467

P value
P[0] -0.045(45)
P[1] 47.7(8.0)

<r >

15 ratio a_w0 / a_fpi

\chi^2/dof= 1.16564

P value
P[0] 0.9942(24)
P[1] 3.93(53)

BAIC average ratio of a: 0.9960(55)

w0 from fpi FLAG: 0.17306(95)

fpi from w0 WP25: 131.03(72)

<r >