Famine and land, 1845-80

While historians once tended to displace the Famine from a pivotal position in modern Irish history, more recent research emphasizes its centrality, and focuses upon the controversial issue of state responsibility. Mortality levels from the Famine place it, proportionately, as one of the most devastating recorded human catastrophes. Official British policy towards Ireland spanned two governments, those of Robert Peel and John Russell, with historians taking a more emollient view of the former: in fact there were significant continuities between the two. The legacy of the Famine was uneven, with commercial and technological advance and the consolidation of both the farming interest and landlordism. On the other hand, recent research emphasizes evidence of continuing economic uncertainty, particularly in the West, together with ongoing landlord-tenant tensions. Rural insecurities, crystallized by the poor harvests of 185964, underlay the post-Famine years, and fed into the politicization of the later 1870s.

Quiescent and flaring X-ray emission from the nearby M/T dwarf binary SCR 1845-6357

Aims: X-ray emission is an important diagnostics to study magnetic activity in very low mass stars that are presumably fully convective and have an effectively neutral photosphere. Methods: We investigate an XMM-Newton observation of SCR 1845-6357, a nearby, ultracool M 8.5 / T 5.5 dwarf binary. The binary is unresolved in the XMM detectors, but the X-ray emission is very likely from the M 8.5 dwarf. We compare its flaring emission to those of similar very low mass stars and additionally present an XMM observation of the M 8 dwarf VB 10. Results: We detect quasi-quiescent X-ray emission from SCR 1845-6357 at soft X-ray energies in the 0.2-2.0 keV band, as well as a strong flare with a count rate increase of a factor of 30 and a duration of only 10 min. The quasi-quiescent X-ray luminosity of log LX = 26.2 erg/s and the corresponding activity level of log LX/Lbol = -3.8 point to a fairly active star. Coronal temperatures of up to 5 MK and frequent minor variability support this picture. During the flare, which is accompanied by a significant brightening in the near-UV, plasma temperatures of 25-30 MK are observed and an X-ray luminosity of LX = 8 × 1027 erg/s is reached. Conclusions: The source SCR 1845-6357 is a nearby, very low mass star that emits X-rays at detectable levels in quasi-quiescence, implying the existence of a corona. The high activity level, coronal temperatures and the observed large flare point to a rather active star, despite its estimated age of a few Gyr.

Johnny Wilson, boxeur américain, champion du monde des middleweight, C.N. New York [cliché Central News] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59518