The relations between pulse broadening and DM as found by Bhat et al. (2004; dashed lines) and Geyer et al. (2017; solid lines) at 149, 334, and 1532 MHz in black, red, and blue, respectively. The functions from Geyer et al. (2017) are shown with scattering indices between −4 and −2, while the function from Bhat et al. (2004) is displayed with the best fitting index of −3.68. Shown as dots, circles, and squares are the W₅₀ pulse widths from this study, as well as from the previous LOTAAS reports of Tan et al. (2018, 2020), Michilli et al. (2020) at different frequencies. These measurements represent upper limits on pulse broadening due to interstellar scattering. Pulse widths from the same pulsar at different frequencies are connected with grey vertical lines. The pulsars discussed in Sect. 3.3 are marked with arrows. The pulse widths of eight pulsars at 149 MHz from Michilli et al. (2020) and Tan et al. (2020), which may be affected by scattering, are marked with grey circles.