## Selection rules, RR couplings on non-BPS branes and their all order $α'$-corrections in type IIA(B) super string theories    [PDF]

Ehsan Hatefi
By computing three and four point functions of non-BPS scattering amplitudes, including a closed string Ramond-Ramond (RR), gauge/scalar and tachyon in type IIA (IIB) super string theories, we discover a unique expansion for tachyon amplitudes in both non-BPS and D-brane anti D-brane formalism. Based on remarks on Chan-Paton factors and arXiv:1304.3711, we propose selection rules for all non-BPS scattering amplitudes of type II super string theory. These selection rules, rule out various non-BPS higher point correlation functions of the string theory. The amplitudes of a closed string RR, one tachyon, one scalar field $$and a closed string RR, one tachyon, one scalar and one gauge field$$ and their all order $\alpha'$ higher derivative corrections have been explored. Having used some of the new Wess-Zumino terms, tachyonic DBI action, this universal tachyon expansion and the proposed selection rule, we are able to produce infinite number of $u'$- channel tachyon and $t$- channel massless scalar poles of $$amplitude in string theory. Based on selection rules upon internal CP matrix of open strings for$$, we reveal that, there should neither be single / double $s',(s'+u'+t)$ channel tachyon, gauge/ scalar poles nor infinite poles.
View original: http://arxiv.org/abs/1307.3520