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We present the results of deep radio observations with the Australia Telescope Compact Array ( ATCA) of the globular cluster NGC 6388. We show that there is no radio source detected (with an rms noise level of 27 μJy) at the cluster centre of gravity or at the locations of any of the Chandra X-ray sources in the cluster. Based on the fundamental plane of accreting black holes which is a relationship between X-ray luminosity, radio luminosity and black hole mass, we place an upper limit of ∼1500 M on the mass of the putative intermediate-mass black hole located at the centre of NGC 6388. We discuss the uncertainties of this upper limit and the previously suggested black hole mass of based on surface density profile analysis. [ABSTRACT FROM AUTHOR]

We have discovered large-scale moving X-ray and radio jets from the microquasar XTE J1550−564. Using X-ray and radio observations performed between 2000 and 2002, we showed that plasma ejected from XTE J1550−564 has been able to travel at relativistic velocities during many years, with evidence for gradual deceleration. The broadband spectrum of the jets is consistent with synchrotron emission from high energy particles accelerated in shocks. Full details can be found in Corbel et al. [Science 298 (2002a) 196], Karret et al. [ApJ 582 (2003) 933] and Tomsick et al. [ApJ (2003) 945]. [Copyright &y& Elsevier]