Deep inelastic scattering from polarized spin-1/2 hadrons at low x from string theory

Abstract

We study polarized deep inelastic scattering of charged leptons from spin-1/2 hadrons at low values of the Bjorken parameter and large 't Hooft coupling in terms of the gauge/string theory duality. We calculate the structure functions from type IIB superstring theory scattering amplitudes. We discuss the role of the non-Abelian Chern-Simons term and the Pauli term from the five-dimensional SU(4) gauged supergravity. Furthermore, the exponentially small-x regime where Regge physics becomes important is analyzed in detail for the antisymmetric structure functions. In this case the holographic dual picture of the Pomeron exchange is realized by a Reggeized gauge field. We compare our results with experimental data of the proton antisymmetric structure function g 1 , obtaining a very good level of agreement.

1/N corrections to F1 and FKovensky1, Michalski2, Schvellinger3 2019Phys. Rev. DSelf Cite11090View full textAdd to dashboardCite

“…This is because the gauge field is actually a particular linear combination of the ten-dimensional graviton and RR 4-form perturbations. This is described in detail in [16,17], where this type of vertex has been used to study the antisymmetric contributions to the hadronic tensor for glueballs and spin-1=2 hadrons. However, it can be seen that the relevant angular integrals vanish in the present case.…”

“…Finally, for the exponentially small region the size of the excited string becomes comparable with the AdS radius. In this case dual Pomeron techniques are useful [7][8][9][10][11][12][13][14][15][16][17]. In previous papers we have calculated F 1 and F 2 by considering the FCS process with the exchange of a single intermediate state for scalar and vector mesons [3][4][5]18].…”

Dispersión inelástica profunda y estructura hadrónica desde la teoría de cuerdas

“…En el capítulo 8, en cambio, estudiamos el caso de los blancos de spin-1/2, concentrándonos en la física de Regge. En este caso seguimos el tratamiento presentado en [11].…”

“…Luego, analizamos las consecuencias fenomenlógicas que se obtienen a partir de estas extensiones. En gran medida, el análisis que presentamos aquí describe los resultados nuevos presentados en [11].…”

“…En esta sección presentamos los resultados obtenidos en nuestra publicación [11], basados en utilizar los métodos que acabamos de describir para comparar la descripción holográfica de la función de estructura g 1 del protón (polarizado) con los datos experimentales disponibles. En primer lugar, vemos que a reemplazando (8.32) esta vez en (5.65) obtenemos la siguiente expresión para g 1 :…”