Radio Pulsar B0950$+$08: Radiation in Magnetosphere and Sparks above Surface

Kavli Affiliate: Kejia Lee

| First 5 Authors: Zhengli Wang, Jiguang Lu, Jinchen Jiang, Shunshun Cao, Kejia Lee

| Summary:

We observed the nearby 100$%$-duty-cycle radio pulsar B0950+08 using the
Five-hundred-meter Aperture Spherical radio Telescope (FAST). We obtained the
polarization profile for its entire rotation, which enabled us to investigate
its magnetospheric radiation geometry and the polar cap sparking pattern. After
we excluded part of the profile in which the linear polarization factor is low
($lesssim 30 %$) and potentially contaminated by position angle jumps, the
rest of the polarization position angle swing fits a classical rotating vector
model (RVM) well. The bestfit RVM indicates that the inclination angle,
$alpha$, and the impact angle, $beta$, of this pulsar, are 100.5$^{circ}$
and $-$33.2$^{circ}$, respectively, suggesting that the radio emission comes
from two poles.We find that, in such RVM geometry, either the annular vacuum
gap or the core vacuum gap model would require that the radio emissions come
from a high-altitude magnetosphere with heights from $sim 0.25~R_{rm LC}$ to
$sim 0.56~R_{rm LC}$, with $R_{rm LC}$ being the light cylinder radius. Both
the main and inter-pulses’ sparking points are located away from the magnetic
pole, which could be relevant to the physical conditions on the pulsar surface.

| Search Query: ArXiv Query: search_query=au:”Kejia Lee”&id_list=&start=0&max_results=3

Read More