Parkes observations for project P1317 semester 2026APRS_01

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The existence of a population of millisecond pulsars (MSPs) in the Galactic bulge is supported, among others, by the Fermi GeV excess, a signal of gamma rays coming from the Galactic center (GC) direction and resembling the cumulative emission of known MSPs. In 2022, we were granted 20h of observations with the Green Bank Telescope to shed light onto the nature of 6 MSP candidates. We discovered two new MSPs, PSR J1740-28 and PSR J1740-2805, towards one of our targets, significantly increasing the number of highly-dispersed MSPs in the GC direction and probably unveiling the first direct evidence of a bulge MSP population. Data collected with the Murriyang telescope between 2023 and 2025 enabled us to obtain binary parameters for both pulsars and revealed that one of them is a black-widow candidate, associated with a circularly polarized source detected in MeerKAT data. Due to the faintness of the other pulsar, its position remains loosely constrained. We propose to continue regular timing observations of these pulsars with Murriyang, in order to constrain their parameter, study their long-term evolution, and rule out that they belong to a new globular cluster.