summarize
1. As the following picture, the scintillation bandwidths get bigger after the gap(57550 - 57800), all points have a same bandwidth and a same frequency ...
2. There are 5 pulsars whose V_iss shown a annual variation. please see the following table
notes: we calculated the scintillation velocity that is given by V_iss=A_iss*(D*υ_d)1/2/(f*τ_d),where D is the distance to the pulsar in kiloparsecs, f is the observing frequency in GHz, υ_d is the scintillation bandwidth in MHz, and τ_d is the scintillation timescale in seconds. The factor A_ISS depends on the assumed geometry of the scattering medium and on the exponent of the density spectrum. For a uniform medium, A_ISS=2.53×104 km/s, while for a thin screen,A_iss=2.78×104*(2(1-s)/s)1/2 km/s (Cordes1998).
For now, I trying to estimate the velocity of interstellar medium and the distance of the model's thin screen.
3. Anti extreme scattering events ???
4. there are some arcs in the secondary spectrum of J0636+5128
5. we translated the scintillation bandwidth into the scattering delay and estimate the impact on timing (all at 1.4 GHz). we found that it is a little possible to increase the timing precision for J1939.
6. we have a total of 13 pulsars, 9 of which Levin2016 has also published their scintillation bandwidth. Comparing with Levin 2016, there are two pulsars with very different results (please see the following table).
