47 research outputs found

    Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

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    New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

    Trends in poverty and inequality since the political transition

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    Using a constructed data series and another data series based on the All Media and Products surveys (AMPS), this paper explores trends in poverty and income distribution over the post-transition period. To steer clear of an unduly optimistic conclusion, assumptions are chosen that would tend to show the least decline in poverty. Whilst there were no strong trends in poverty for the period 1995 to 2000, both data series show a considerable decline in poverty after 2000, particularly in the period 2002-2004. Poverty dominance testing shows that this decline is independent of the poverty line chosen or whether the poverty headcount, the poverty ratio or the poverty severity ratio are used as measure. We find likely explanations for this strong and robust decline in poverty in the massive expansion of the social grant system as well as possibly in improved job creation in recent years. Whilst the collective income of the poor (using our definition of poverty) was only R27 billion in 2000, the grants (in constant 2000 Rand values) have expanded by R22 billion since. Even if the grants were not well targeted at the poor (and in the past they have been), a large proportion of this spending must have reached the poor, thus leaving little doubt that poverty must have declined substantially
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