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arXiv · hep-ph/9706528

Squeezed condensate of gluons and the mass of the eta'

H. -P. Pavel·D. Blaschke·V. N. Pervushin·G. Roepke·M. K. Volkov
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Abstract

The relation between the large mass of the $η'$ and the structure of the gluon vacuum via the $U_A(1)$ anomaly is discussed. A squeezed gluon vacuum is considered as an alternative to existing models. Considering Witten's formula for the $η_0$ mass we show that the contact term can give a sizable contribution and relate it to the physical gluon condensate. The values of the gluon condensate obtained through this relation are compared with the value by Shifman, Vainshtein and Zakharov and the recent update values by Narison.

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H. -P. Pavel, D. Blaschke, V. N. Pervushin, G. Roepke, M. K. Volkov. 1997-12-05. Squeezed condensate of gluons and the mass of the eta'. https://arxiv.org/abs/hep-ph/9706528

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