Pulsars are arguably the only astrophysical sources whose emission spans the entire electromagnetic spectrum , from decameter radio wavelengths to TeV energies .
The LOw Frequency ARray ( LOFAR ) offers the unique possibility to study pulsars over a huge fractional bandwidth in the bottom 4 octaves of the radio window , from 15–240 MHz .
Here we present a LOFAR study of pulsar single pulses , focussing specifically on the bright nearby pulsar B0809+74 .
We show that the spectral width of bright low-frequency pulses can be as narrow as 1 MHz and scales with increasing frequency as \Delta f / f _ { \mathrm { c } } \sim 0.15 , at least in the case of the PSR B0809+74 .
This appears to be intrinsic to the pulsar , as opposed to being due to propagation effects .
If so , this behavior is consistent with predictions by the strong plasma turbulence model of pulsar radio emission .
We also present other observed properties of the single pulses and discuss their relation to other single-pulse phenomena like giant pulses .