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The X-ray emission of neutron stars enables a probe of their temperatures, geometries, and magnetospheric properties. The current number of X-ray emitting pulsars is insufficient to rule out observational biases that may arise from poorly known distance, age, or location of the neutron stars. One approach to overcome such biases is to create a distance-limited sample with sufficiently deep observations. With the aim of better sampling of the nearby ($\lesssim$ 2kpc) neutron stars population, we started an XMM-Newton survey of pulsars to measure their X-ray fluxes or derive respective constraining upper limits. We investigated 14 nearby pulsars for potential X-ray counterparts using different energy bands and detectors. In addition to our new XMM-Newton data, we also considered archival data and catalogs. We discuss source properties and also check for alternative counterparts to the X-ray sources. In our new XMM-Newton data, we found two pulsar counterpart candidates with significance above over $4\sigma$ and one candidate with $3.5\sigma$ by combining EPIC camera detection likelihoods. We also report the detection of potential X-ray counterparts to 8 radio pulsars in the 4XMM-DR10 catalog which have not been reported in the literature., Comment: 10 pages, 3 figures, 7 tables, accepted for publication in Astronomy and Astrophysics

We present the results of deep, high-resolution, multi-band optical observations of the field of the young (~ 5,000 yrs) 16 ms X-ray pulsar PSR J0537$-$6910 performed with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope (HST). Although a few new potential counterparts have been detected within or close to the revised Chandra X-ray error circle (~1 arcsec) of the pulsar, only two of them (with magnitudes m_{814W} ~ 23.9 and m_{814W} ~ 24.2) show indications of a peculiar spectrum which could be related to optical emission from the pulsar. This might be true also for a third, fainter, candidate detected only in one filter (with magnitude m_{814W} ~ 26.7). If either of the two brighter candidates is indeed the actual counterpart, the optical output of PSR J0537-6910 would make it similar to young Crab-like pulsars. If not, it would mean that PSR J0537-6910 is significantly underluminous with respect to all pulsars detected in the optical, 7 pages, 5 figures, Astronomy & Astrophysics, in press

Context. Optical-ultraviolet (UV) observations of > 100 Myr pulsars are crucial to understand the long-term evolution of neutron stars, including the late stages of the neutron star cooling. The 166 Myr old pulsar PSR J0108-1431 is one of the best targets since it is the oldest non-recycled pulsar with a candidate counterpart, detected with the Very Large Telescope (VLT). Aims. Aim of our observations is to obtain a firm detection of its candidate counterpart, only detected with marginal significance and to measure anew its flux in the U and B bands, for which we obtained only uncertain values. Methods. We observed the PSR J0108-1431 field with the FOcal Reducer/low dispersion Spectrograph (FORS2) at the VLT, exploiting the updated pulsar radio coordinates obtained from recent VLBI observations. Results. Due to non-optimal seeing conditions, we only reached 3σ detection limits of U ∼ 26.5 and B ∼ 27.2, i.e. not incompatible with the fluxes of the candidate counterpart (U = 26.4 ± 0.3; B = 27.9 ± 0.5) that we measured in our previous VLT observations. Conclusions. We can not rule out that the proposed counterpart, detected at the edge of an elliptical galaxy, is real and that we could not detect it just because its flux is close to the detection limit of our new VLT observations. Due to its blue spectrum and proximity to the galaxy, UV observations with the Hubble Space Telescope are more suited to confirm the pulsar identification.