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Using results from radio and X-ray observations of millisecond pulsars in 47 Tucanae, and extensive HST U, V, I imaging of the globular cluster core, we have derived a common astrometric solution good to < 0.1. A close positional coincidence is found for 47 Tuc U, a 4.3 ms pulsar in a 0.429 day orbit, detected in radio and X-rays, with an m_V = 20.9 blue star. Analysis of extensive time series data for this optical candidate shows a 0.004 magnitude semi-amplitude variation at the period and phase expected from the radio ephemeris, and the optical variations are spatially coincident with the candidate. This provides secure optical detection of the white dwarf companion to the millisecond pulsar, the first such detection in a globular cluster, allowing for comparisons to recent models for such companions with dependencies on mass and age.
In the last 10 years 20 millisecond pulsars have been discovered in the globular cluster 47 Tucanae. Hitherto, only 3 of these had published timing solutions. Here we improve upon these 3 and present 12 new solutions. These measurements can be used t
We present the results of a comprehensive search for stellar variability in the globular cluster 47 Tucanae. Using the Mount Stromlo 40-inch (1m) telescope at Siding Spring Observatory and a combined V+R filter, we have detected 100 variable stars ac
We report on the optical identification of the companion to the eclipsing millisecond pulsar PSR J1701$-$3006B in the globular cluster NGC 6266. A relatively bright star with an anomalous red colour and an optical variability ($sim$ 0.2 mag) that nic
Using images from the Hubble Space Telescope Wide-Field Camera 3, we measure the rate of diffusion of stars through the core of the globular cluster 47 Tucanae using a sample of young white dwarfs identified in these observations. This is the first d
We report the detection of ionized intracluster gas in the globular cluster 47 Tucanae. Pulsars in this cluster with a negative period derivative, which must lie in the distant half of the cluster, have significantly higher measured integrated electr