7,079 research outputs found
An Understanding of the Shoulder of Giants: Jovian Planets around Late K Dwarf Stars and the Trend with Stellar Mass
Analyses of exoplanet statistics suggest a trend of giant planet occurrence
with host star mass, a clue to how planets like Jupiter form. One missing piece
of the puzzle is the occurrence around late K dwarf stars (masses of
0.5-0.75Msun and effective temperatures of 3900-4800K). We analyzed four years
of Doppler radial velocities data of 110 late K dwarfs, one of which hosts two
previously reported giant planets. We estimate that 4.0+/-2.3% of these stars
have Saturn-mass or larger planets with orbital periods <245d, depending on the
planet mass distribution and RV variability of stars without giant planets. We
also estimate that 0.7+/-0.5% of similar stars observed by Kepler have giant
planets. This Kepler rate is significantly (99% confidence) lower than that
derived from our Doppler survey, but the difference vanishes if only the single
Doppler system (HIP 57274) with completely resolved orbits is considered. The
difference could also be explained by the exclusion of close binaries (without
giant planets) from the Doppler but not Kepler surveys, the effect of
long-period companions and stellar noise on the Doppler data, or an intrinsic
difference between the two populations. Our estimates for late K dwarfs bridge
those for solar-type stars and M dwarfs and support a positive trend with
stellar mass. Small sample size precludes statements about finer structure,
e.g. a "shoulder" in the distribution of giant planets with stellar mass.
Future surveys such as the Next Generation Transit Survey and the Transiting
Exoplanet Satellite Survey will ameliorate this deficiency.Comment: Accepted to The Astrophysical Journa
Social Policy under the Global Shadow of Right-wing Populism:The Dark Sides of Social Policy: From Neoliberalism to Resurgent Right-wing Populism
This Forum Debate explores the confluence of neoliberal, populist, conservative and reactionary influences on contemporary ideologies and practices of social policy, with a focus on the poorer peripheries of global capitalism. Several fundamental tensions are highlighted, which are largely overlooked by the social policy and development literatures. First, many recent social policy innovations have been discredited by their association with neoliberalism. The rising political Right has been much more successful than the Left at exploiting this discontent, despite simultaneously deepening many aspects of neoliberalism once in power. At the same time, right-wing movements have proactively used social policy as a political tool to fashion the social order along lines deemed amenable for their interests and ideologies, expressed along nationalist, racialized, ethnicized, nativist, religious, patriarchal or other lines, and to innovate practices of segregation, exclusion and subordination. While these synergies of neoliberal and right-wing populism are observed globally, they need to be carefully and differentially interpreted from the perspective of late industrializing (or late welfare state) peripheral countries. Nonetheless, common themes occurring across both centres and peripheries, as identified by the invited contributions to this Debate section, include exclusionary identity politics, hierarchical and subordinating inclusions, and patriarchal familialism. In this context, segregationism is an ominous possibility of post-neoliberal social policy
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