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Search for Postinflationary QCD Axions with a Quantum-Limited Tunable Microwave Receiver
G Sardo Infirri1,2, D Alesini3, C Braggio1,2
1INFN, Sezione di Padova, 35100 Padova, Italy.
None:
A search for cosmological axions has been performed by scanning a frequency region of 38 MHz centered at about 10.2 GHz, corresponding to an axion mass m_{a}≃42 μeV. The QUAX experimental apparatus, a haloscope comprised of a 1-liter volume tunable cavity immersed in an 8 T magnetic field and a quantum-limited detection chain, set limits on the axion-photon coupling at the 10^{-14} GeV^{-1} level. As no signal candidate has been observed, viable hadronic axion models are ruled out in a currently preferred postinflationary region m_{a}>40 μeV.
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