We present a summary of the Fermi Pulsar Search Consortium (PSC), an international collaboration of radio astronomers and members of the Large Area Telescope (LAT) collaboration, whose goal is to organize radio follow-up observations of Fermi pulsars and pulsar candidates among the LAT γ-ray source population. The PSC includes pulsar observers with expertise using the world's largest radio telescopes that together cover the full sky. We have performed very deep observations of all 35 pulsars discovered in blind frequency searches of the LAT data, resulting in the discovery of radio pulsations from four of them. We have also searched over 300 LAT γ-ray sources that do not have strong associations with known γ-ray emitting source classes and have pulsar-like spectra and variability characteristics. These searches have led to the discovery of a total of 43 new radio millisecond pulsars (MSPs) and four normal pulsars. These discoveries greatly increase the known population of MSPs in the Galactic disk, more than double the known population of so-called 'black widow' pulsars, and contain many promising candidates for inclusion in pulsar timing arrays.

Context. Globular clusters (GCs) contain a unique pulsar population, with many exotic systems that can form only in their dense stellar environments. Such systems are potentially very interesting for new tests of gravity theories and neutron-star mass measurements. Aims. The leap in sensitivity of the upgraded Giant Metrewave Radio Telescope (uGMRT) in India, especially at low radio frequencies (< 1 GHz), motivated a new search for radio pulsars in a group of eight southern GCs. We aim to image these clusters in order to have independent measurements of the radio fluxes of known pulsars and the identification of bright radio sources that could be pulsars missed by pulsation search pipelines due to their inherent limitations. Methods. The observations were conducted at 650 MHz (Band 4 receivers) on Terzan 5, NGC 6441, NGC 6440, and NGC 6544, and at 400 MHz (Band 3 receivers) on NGC 6652, NGC 6539, NGC 1851, and M 30. Segmented acceleration and jerk searches were performed on the data. Simultaneously, we obtained interferometric data on these clusters, which were later converted into radio images.Results. We discovered PSR J1835−3259B, a 1.83-ms pulsar in NGC 6652; this is in a near-circular wide orbit of 28.7-hr with an unidentified low-mass (∼ 0.2) companion, likely a helium white dwarf. We derived a ten-year timing solution for this system. We also present measurements of scattering, flux densities, and spectral indices for some of the previously known pulsars in these GCs. Conclusions. A significant fraction of the pulsars in these clusters have steep spectral indices. Additionally, we detected eight radio point sources not associated with any known pulsar positions in the radio images. There are four newly identified sources, three in NGC 6652 and one in NGC 6539, as well as one previously identified source in NGC 1851, NGC 6440, NGC 6544, and Terzan 5. Surprisingly, our images show that our newly discovered pulsar, PSR J1835−3259B, is the brightest pulsar in all GCs we have imaged; like other pulsars with broad profiles (Terzan 5 C and O), its flux density in the radio images is much larger than in its pulsations. This indicates that their pulsed emission is only a fraction of their total emission. The detection of radio sources outside the core radii but well within the tidal radii of these clusters show that future GC surveys should complement the search analysis by using the imaging capability of interferometers, and preferentially synthesise large number of search beams in order to obtain a larger field of view.

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Galactic plane radio surveys play a key role in improving our understanding of a wide range of astrophysical phenomena. Performing such a survey using the latest interferometric telescopes produces large data rates necessitating a shift towards fully or quasi-real-time data analysis with data being stored for only the time required to process them. We present here the overview and setup for the 3000 hour Max-Planck-Institut für Radioastronomie (MPIfR) MeerKAT Galactic Plane survey (MMGPS). The survey is unique by operating in a commensal mode, addressing key science objectives of the survey including the discovery of new pulsars and transients as well as studies of Galactic magnetism, the interstellar medium and star formation rates. We explain the strategy coupled with the necessary hardware and software infrastructure needed for data reduction in the imaging, spectral and time domains. We have so far discovered 78 new pulsars including 17 confirmed binary systems of which two are potential double neutron star systems. We have also developed an imaging pipeline sensitive to the order of a few tens of micro-Jansky with a spatial resolution of a few arcseconds. Further science operations with an in-house built S-Band receiver operating between 1.7-3.5 GHz are about to commence. Early spectral line commissioning observations conducted at S-Band, targeting transitions of the key molecular gas tracer CH at 3.3 GHz already illustrate the spectroscopic capabilities of this instrument. These results lay a strong foundation for future surveys with telescopes like the Square Kilometre Array (SKA).