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ABSTRACT We report here on the first results of a systematic monitoring of southern glitching pulsars at the Argentine Institute of Radioastronomy that started in the year 2019. We detected a major glitch in the Vela pulsar (PSR J0835 − 4510) and two small glitches in PSR J1048 − 5832. For each glitch, we present the measurement of glitch parameters by fitting timing residuals. We then make an individual pulse study of Vela in observations before and after the glitch. We selected 6 days of observations around the major glitch on 2021 July 22 and study their statistical properties with machine learning techniques. We use variational autoencoder (VAE) reconstruction of the pulses to separate them clearly from the noise. We perform a study with self-organizing map (SOM) clustering techniques to search for unusual behaviour of the clusters during the days around the glitch not finding notable qualitative changes. We have also detected and confirmed recent glitches in PSR J0742 − 2822 and PSR J1740 − 3015. 

Context.We report here on new results of the systematic monitoring of southern glitching pulsars at the Argentine Institute of Radioastronomy. In particular, we study in this work the new major glitch in the Vela pulsar (PSR J0835−4510) that occurred on 2024 April 29. Aims.We aim to thoroughly characterise the rotational behaviour of the Vela pulsar around its last major glitch and investigate the statistical properties of its individual pulses around the glitch. Methods.We characterise the rotational behaviour of the pulsar around the glitch through the pulsar timing technique. We measured the glitch parameters by fitting timing residuals to the data collected during the days surrounding the event. In addition, we study Vela individual pulses during the days of observation just before and after the glitch. We selected nine days of observations around the major glitch on 2024 April 29 and studied their statistical properties with the Self-Organizing Maps (SOM) technique. We used Variational AutoEncoder (VAE) reconstruction of the individual pulses to separate them clearly from the noise. Results.We obtain a precise timing solution for the glitch. We find two recovery terms of ∼3 days and ∼17 days. We find a correlation of high amplitude with narrower pulses while not finding notable qualitative systematic changes before and after the glitch. 

Context.The radio pulsar PSR J0742−2822 is known to exhibit rapid changes between different pulse profile states that correlate with changes in its spin-down rate. However, the connection between these variations and the glitch activity of the pulsar remains unclear. Aims.We aim to study the evolution of the pulse profile and spin-down rate of PSR J0742−2822 in the period MJD 58810–60149 (November 2019 to July 2023), which includes the glitch on MJD 59839 (September 2022). In particular, we looked for pulse profile or spin-down changes associated with the 2022 glitch. Methods.We observed PSR J0742−2822 with a high cadence from the Argentine Institute of Radioastronomy (IAR) between November 2019 and July 2023. We used standard timing tools to characterise the times of arrival of the pulses and to study the pulsar rotation and, particularly, the oscillations ofν̇. We also studied the evolution of the pulse profile. For both of them, we compared their behaviour before and after the 2022 glitch. Results.With respect toν̇, we find that oscillations diminished in amplitude after the glitch. We find four different components contributing to the pre-glitchν̇oscillations, and only one component after the glitch. With regard to the emission, we find the pulse profile has two main peaks. We detect an increase in theW₅₀of the total pulse profile of ∼12% after the glitch and we find the amplitude of the trailing peak increased with respect to the amplitude of the leading one after the glitch. Conclusions.We find significant changes in the pulse profile and the spin-down rate of PSR J0742−2822 after its 2022 glitch. These results suggest that there is a strong coupling between the internal superfluid of the neutron star and its magnetosphere, and that pulse profile changes may be led by this coupling instead of being led purely by magnetospheric effects. 

We performed a series of 1381 full numerical simulations of high energy collision of two black holes to search for the maximum recoil velocity after their merger. We studied equal mass binaries with opposite spins pointing along the orbital plane to maximize asymmetric gravitational radiation and performed a search of spin orientations in the plane, impact parameters, and initial linear momenta to find a maximum recoil velocity extrapolated to the extreme spinning case of [Formula: see text][Formula: see text]km/s, thus tightly bounding recoil by [Formula: see text] the speed of light. 

We study the evolution of close triple black hole system with full numerical relativity techniques. We consider an equal mass non spinning hierarchical system with an inner binary ten orbits away from merger and study the effects of the third outer black hole on the binary’s merger time and its eccentricity evolution. We find a generic time delay and an increase in the number of orbits to merger of the binary, that can be modeled versus the distance D to the third black hole as ∼1=D^2.5 . On the other hand, we find that the orientation of the third black hole orbit has little effect on the binary’s merger time when considering a fiducial initial distance of D = 30M to the binary (with initial orbital separation d = 8M). In those scenarios the evolution of the inner binary eccentricity presents a steady decay, roughly as expected, but in addition shows a modulation with the time