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تسجيل مستخدم جديدCMB targets after the latest Planck data release
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We show that a combination of the simplest $alpha$-attractors and KKLTI models related to Dp-brane inflation covers most of the area in the ($n_{s}$, $r$) space favored by Planck 2018. For $alpha$-attractor models, there are discrete targets $3alpha=1,2,...,7$, predicting 7 different values of $r = 12alpha/N^{2}$ in the range $10^{-2} gtrsim r gtrsim 10^{-3}$. In the small $r$ limit, $alpha$-attractors and Dp-brane inflation models describe vertical $beta$-stripes in the ($n_{s}$, $r$) space, with $n_{s}=1-beta/N$, $beta=2, {5over 3},{8over 5}, {3over 2},{4over 3}$. A phenomenological description of these models and their generalizations can be achieved in the context of pole inflation. Most of the $1sigma$ area in the ($n_{s}$, $r$) space favored by Planck 2018 can be covered models with $beta = 2$ and $beta = 5/3$. Future precision data on $n_s$ may help to discriminate between these models even if the precision of the measurement of $r$ is insufficient for the discovery of gravitational waves produced during inflation.
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