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arXiv · 1406.4172

Subleading Soft Factor for String Disk Amplitudes

Burkhard U. W. Schwab
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Abstract

We investigate the behavior of superstring disk scattering amplitudes in the presence of a soft external momentum at finite string tension. We prove that there are no $α'$-corrections to the field theory form of the subleading soft factor $S^{(1)}$. At the end of this work, we also comment on the possibility to find the corresponding subleading soft factors in closed string theory using our result and the KLT relations.

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Burkhard U. W. Schwab. 2014-08-26. Subleading Soft Factor for String Disk Amplitudes. https://doi.org/10.1007/jhep08(2014)062

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