Constraining the Rate of Primordial Black-Hole Explosions and Extra Dimension Scale using a Low-Frequency Radio Antenna Array

Understand

An exploding primordial black-hole (PBH) may produce a single pulse of electromagnetic radiation detectable at the low-frequency end of the radio spectrum.

• Furthermore, a radio transient from an exploding PBH could be a signature of an extra spatial dimension.
• We describe here an approach for searching for PBH explosions using a low-frequency radio antenna array, and as a practical example, the results of a such a search using the Eight-meter-wavelength Transient Array (ETA).
• No compelling astrophysical signal was detected in $\approx 4$ hours of data implying an observational upper limit on the rate of exploding PBHs is $4.2 \times 10^{-7} \,\rm{pc}^{-3}\,\rm{yr}^{-1}$ for an exploding PBH with a fireball Lorentz factor of $10^{4.5}$ for the standard scenario of Page and Hawking.