${{\boldsymbol \rho}{(770)}}$ RANGE PARAMETER INSPIRE search

The range parameter $\mathit R$ enters an energy-dependent correction to the width, of the form (1 $+$ $\mathit q{}^{2}_{\mathit r}$ $\mathit R{}^{2}$) $/$ (1 $+$ $\mathit q{}^{2}$ $\mathit R{}^{2}$), where $\mathit q$ is the momentum of one of the pions in the ${{\mathit \pi}}{{\mathit \pi}}$ rest system. At resonance, $\mathit q$ = $\mathit q_{\mathit r}$.
VALUE (GeV${}^{-1}$) DOCUMENT ID TECN CHG  COMMENT
$5.3$ ${}^{+0.9}_{-0.7}$ 1
CHABAUD
1983
ASPK 0 17 ${{\mathit \pi}^{-}}{{\mathit p}}$ polarized
1  The old PISUT 1968 value, properly corrected, was $3.2$ $\pm0.6$.
  References:
CHABAUD 1983
NP B223 1 Experimental Indications for a $2+{}^{+}{}^{}$ non (${\mathit {\mathit q}}{\mathit {\overline{\mathit q}}}$) Object