2015/05/31 by Yi-Jian Du, Hui Luo · 34 citations
Mathematics · Physics and Astronomy · #Amplitude #Black Holes and Theoretical Physics #Limit (mathematics) #Mathematical analysis #Mathematics #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Shell (structure) #Theoretical and Computational Physics #Tree (set theory) #hep-th
paper · pdf · doi:10.1007/jhep08(2015)058
published in Journal of High Energy Physics 2015(8) (Springer Nature) · 41 pages, 6 tables, 9 figures, minor revised, more content about nonadjacent double soft limit, update the references
openalex publication_date 2015/08/01 · arxiv created 2015/08/26 · arxiv updated 2015/08/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this paper, we study the single and double soft behaviors of tree level off-shell currents and on-shell amplitudes in nonlinear sigma model (NLSM). We first propose and prove the leading soft behavior of the tree level currents with a single soft particle. In the on-shell limit, this single soft emission becomes the Adler’s zero. Then we establish leading and subleading soft behaviors of tree level currents with two adjacent soft particles. With a careful analysis of the on-shell limit, we obtain the double soft behaviors of on-shell amplitudes where the two soft particles are adjacent to each other. By applying Kleiss-Kuijf (KK) relation, we further obtain the leading and subleading behaviors of amplitudes with two nonadjacent soft particles.