Dwarf pulses of ten pulsars detected by FAST

Yi Yan, J. L. Han, D. J. Zhou, L. Xie, F. F. Kou, P. F. Wang, C. Wang, T. Wang

Published 2024-03-02Version 1

How pulsars radiate is a long-standing problem. Detailed polarization measurements of individual pulses shed lights on currently unknown emission processes. Recently, based on super-sensitive observations, dwarf pulses have been recognized as weak narrow pulses often appearing during the nulling state. In this study, we report the detection of dwarf pulses from ten pulsars, PSRs B0525+21, B1237+25, J1538+2345, J1824$-$0127, J1851$-$0053, B1901+10, J1939+10, B1944+17, B2000+40 and J2112+4058, based on observations conducted with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Dwarf pulses of five pulsars are clearly discernible in the two-dimensional distribution of pulse intensity and pulse width. For the other five pulsars, PSRs J1538+2345, J1824$-$0127, J1939+10, B2000+40 and J2112+4058, only a few dwarf pulses are detected from pulse stacks. The dwarf pulses can emerge in both cone and core emission components for B1237+25, and the polarization angles of these dwarf pulses are mostly in the orthogonal polarization mode of normal pulses for B1944+17. In general, pulsars with detected dwarf pulses tend to be located within the `death valley' region of the distribution of pulsar periods and period derivatives.