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arXiv · 0802.0934

How Resonances can synchronise with Thresholds

D. V. Bugg
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Abstract

The mechanism by which a threshold may capture a resonance is examined. It involves a threshold cusp interfering constructively with either or both (i) a resonance produced via confinement, (ii) attractive t- and u-channel exchanges. The fo(980), X(3872) and Z(4430) are studied in detail. The fo(980) provides a valuable model of the locking mechanism. The X(3872) is too narrow to be fitted by a cusp, and requires either a resonance or virtual state. The Z(4430) can be fitted as a resonance but also can be fitted successfully by a cusp with no nearby resonant pole.

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D. V. Bugg. 2008-02-17. How Resonances can synchronise with Thresholds. https://doi.org/10.1088/0954-3899%2F35%2F7%2F075005

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