2021RAA....21...42D

PSR J0742-2822 is known for its quasi-periodic changes in the observed pulse profile and spin-down rate. In this paper, we analyzed 13 years of timing data obtained with the Nanshan 25-m radio telescope and the Parkes 64-m radio telescope. We found that the average values of the spin-down rate <{dot}ν> of this pulsar changed in four different states. We investigated the correlation between {dot}ν and W₅₀, and ascertained that the correlation changed in different <{dot}ν> states. Moreover, not all the changes in <{dot}ν> states and correlation can be associated with glitch activities. We examined the long term evolution of γ-ray flux (0.1-300 GeV) and the pulse profiles corresponding to the four different states using Fermi-LAT Pass 8 (P8R3) data from 2008 August 5 to 2019 October 1. We did not detect a significant change in γ-ray flux or the pulse profile. Our results suggest that the connection between pulsar rotation and emission is more complex than previously reported for this pulsar.