We have measured the running of the effective QED coupling constant $\alpha(s)$ in the time-like region $0.6<\sqrt s< 0.975$ GeV with the KLOE detector at DA$\Phi$NE using the Initial State Radiation process $e^+e^-\to\mu^+ \mu^-\gamma$. It represents the first measurement of the running of $\alpha(s)$ in this energy region. Our results show a more than 5$\sigma$ significance of the hadronic contribution to the running of $\alpha(s)$, which is the strongest direct evidence both in time- and space-like regions achieved in a single measurement. By using the $e^+e^-\to\pi^+\pi^-$ cross section measured by KLOE, the real and imaginary part of the shift $\Delta\alpha(s)$ has been extracted. By a fit of the real part of $\Delta\alpha(s)$ and assu...
The evolution of the electromagnetic coupling, alpha, in the momentum-transfer range 1800 GeV2 \u3c ...
We have measured the cross section $\sigma(e^+e^-\to\pi^+\pi^-\gamma)$ with the KLOE detector at DA$...
The KLOE experiment at the φ - factory DAΦNE in Frascati near Rome is the first to have employed Ini...
We have measured the running of the effective QED coupling constant $\alpha(s)$ in the time-like reg...
We have measured the running of the effective QED coupling constant alpha(s) in the time-like region...
The KLOE experiment at the ϕ-factory DAΦNE in Frascati is the first to have employed Initial State R...
We have studied the structure of hadronic events with a hard, %radiated isolated photon in the final...
The evolution of the electromagnetic coupling, $\alpha$, in the momentum-transfer range 1800 GeV$^2 ...
The evolution of the electromagnetic coupling, alpha, in the momentum-transfer range 1800 GeV2 \u3c ...
We have measured the cross section $\sigma(e^+e^-\to\pi^+\pi^-\gamma)$ with the KLOE detector at DA$...
The KLOE experiment at the φ - factory DAΦNE in Frascati near Rome is the first to have employed Ini...
We have measured the running of the effective QED coupling constant $\alpha(s)$ in the time-like reg...
We have measured the running of the effective QED coupling constant alpha(s) in the time-like region...
The KLOE experiment at the ϕ-factory DAΦNE in Frascati is the first to have employed Initial State R...
We have studied the structure of hadronic events with a hard, %radiated isolated photon in the final...
The evolution of the electromagnetic coupling, $\alpha$, in the momentum-transfer range 1800 GeV$^2 ...
The evolution of the electromagnetic coupling, alpha, in the momentum-transfer range 1800 GeV2 \u3c ...
We have measured the cross section $\sigma(e^+e^-\to\pi^+\pi^-\gamma)$ with the KLOE detector at DA$...
The KLOE experiment at the φ - factory DAΦNE in Frascati near Rome is the first to have employed Ini...