# Transverse–Spin Quark Distributions from Asymmetry Data and Symmetry Arguments

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## Abstract

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## 1. Introduction

## 2. SIDIS with a Transversely Polarized Target

## 3. Sivers Distributions

## 4. Transversity Distributions from Collins Asymmetries

## 5. Transversity Distributions from Difference Asymmetries

## 6. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

DSS | de Florian, Sassot, Stratmann |

QCD | Quantum chromodynamics |

SIDIS | Semi-inclusive deep inelastic scattering |

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**Figure 1.**The first ${k}_{T}^{2}$ moments of the Sivers valence distributions, $x{f}_{1T}^{\perp \left(1\right){u}_{v}}$ (red solid circles) and $x{f}_{1T}^{\perp \left(1\right){d}_{v}}$ (black open circles).

**Figure 2.**Valence transversity distributions. Black circles represent $x{h}_{1}^{{u}_{v}}$ and red squares represent $x{h}_{1}^{{d}_{v}}$.

**Figure 3.**Ratio ${h}_{1}^{{d}_{v}}/{h}_{1}^{{u}_{v}}$ from the difference asymmetries. Solid circles: determination from existing measurements. Open circles: projection for future COMPASS run.

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**MDPI and ACS Style**

Barone, V.; Martin, A.; Bradamante, F.
Transverse–Spin Quark Distributions from Asymmetry Data and Symmetry Arguments. *Symmetry* **2021**, *13*, 116.
https://doi.org/10.3390/sym13010116

**AMA Style**

Barone V, Martin A, Bradamante F.
Transverse–Spin Quark Distributions from Asymmetry Data and Symmetry Arguments. *Symmetry*. 2021; 13(1):116.
https://doi.org/10.3390/sym13010116

**Chicago/Turabian Style**

Barone, Vincenzo, Anna Martin, and Franco Bradamante.
2021. "Transverse–Spin Quark Distributions from Asymmetry Data and Symmetry Arguments" *Symmetry* 13, no. 1: 116.
https://doi.org/10.3390/sym13010116