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arXiv · 2504.15702

Form factors from string amplitudes

Qu Cao
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Abstract

In this letter, we propose a stringy model for $n$-point tree-level form factor with the off-shell operator in the scalar and gluon theories, from the bosonic string disk amplitude: $n$ open string states and $1$ closed string state scatter on the disk. In the field-theory limit ($\alpha'\to0$), the stringy form factor reduces to the form factor, helps us to investigate the hidden properties of the field-theory form factors, manifest the factorization and soft behaviors, and uncover more non-trivial relations between form factors and scattering amplitudes.

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Qu Cao. 2025-04-22. Form factors from string amplitudes. https://doi.org/10.1103/svb5-mhpc

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