TY - JOUR

T1 - Search for the dark photon in $π^0$ decays

AU - Ruggiero, Giuseppe

AU - NA48/2 Collaboration

PY - 2015/6/30

Y1 - 2015/6/30

N2 - A sample of $1.69\times 10^7$ fully reconstructed $\pi^0\to\gamma e^+e^-$ decay candidates collected by the NA48/2 experiment at CERN in 2003--2004 is analysed to search for the dark photon ($A'$) production in the $\pi^0\to\gamma A'$ decay followed by the prompt $A'\to e^+e^-$ decay. No signal is observed, and an exclusion region in the plane of the dark photon mass $m_{A'}$ and mixing parameter $\varepsilon^2$ is established. The obtained upper limits on $\varepsilon^2$ are more stringent than the previous limits in the mass range $9~{\rm MeV}/c^2m_{A}

AB - A sample of $1.69\times 10^7$ fully reconstructed $\pi^0\to\gamma e^+e^-$ decay candidates collected by the NA48/2 experiment at CERN in 2003--2004 is analysed to search for the dark photon ($A'$) production in the $\pi^0\to\gamma A'$ decay followed by the prompt $A'\to e^+e^-$ decay. No signal is observed, and an exclusion region in the plane of the dark photon mass $m_{A'}$ and mixing parameter $\varepsilon^2$ is established. The obtained upper limits on $\varepsilon^2$ are more stringent than the previous limits in the mass range $9~{\rm MeV}/c^2m_{A}

KW - hep-ex

U2 - 10.1016/j.physletb.2015.04.068

DO - 10.1016/j.physletb.2015.04.068

M3 - Journal article

VL - 746

SP - 178

EP - 185

JO - Physics Letters B

JF - Physics Letters B

SN - 0370-2693

ER -