## Abstract

In this study, we introduce a new class of rational elliptic 3-folds, which we refer to as “1/2 Calabi-Yau 3-folds”. We construct elliptically fibered Calabi-Yau 3-folds by utilizing these rational elliptic 3-folds. The construction yields a novel approach to build elliptically fibered Calabi-Yau 3-folds of various Mordell-Weil ranks. Our construction of Calabi-Yau 3-folds can be considered as a three-dimensional generalization of the operation of gluing pairs of 1/2 K3 surfaces to yield elliptic K3 surfaces. From one to seven U(1)s form in six-dimensional *N* = 1 F-theory on the constructed Calabi-Yau 3-folds. Seven tensor multiplets arise in these models.

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Kimura, Y. \( \frac{1}{2} \) Calabi-Yau 3-folds, Calabi-Yau 3-folds as double covers, and F-theory with U(1)s.
*J. High Energ. Phys.* **2020, **76 (2020). https://doi.org/10.1007/JHEP02(2020)076

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### Keywords

- Differential and Algebraic Geometry
- F-Theory
- Gauge Symmetry
- Super- string Vacua