Definition of "endline"

We confirm that the slope of the critical endline takes the value of − 2 {\displaystyle -2} , and find that the second derivative is positive, at the SU(3)-flavor symmetric point on the Columbia plot parametrized with the strange quark mass m s {\displaystyle m_{s}} and degenerated up-down quark mass m l {\displaystyle m_{\rm {l}}} ..

2016, Yoshinobu Kuramashi, Yoshifumi Nakamura, Shinji Takeda, Akira Ukawa, “Critical endline of the finite temperature phase transition for 2+1 flavor QCD around the SU(3)-flavor symmetric point”, in arXiv‎