English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We study the mass distribution in the late-type dwarf galaxy NGC 2976 throughstellar kinematics obtained with the VIRUS-P integral-field spectrograph andanisotropic Jeans models as a test of cosmological simulations and baryonicprocesses that putatively alter small-scale structure. Previous measurements ofthe H-alpha emission-line kinematics have determined that the dark matter haloof NGC 2976 is most consistent with a cored density profile. We find that thestellar kinematics are best fit with a cuspy halo. Cored dark matter halo fitsare only consistent with the stellar kinematics if the stellar mass-to-lightratio is significantly larger than that derived from stellar populationsynthesis, while the best-fitting cuspy model has no such conflict. Theinferred mass distribution from a harmonic decomposition of the gaseouskinematics is inconsistent with that of the stellar kinematics. This differenceis likely due to the gas disk not meeting the assumptions that underlie theanalysis such as no pressure support, a constant kinematic axis, and planarorbits. By relaxing some of these assumptions, in particular the form of thekinematic axis with radius, the gas-derived solution can be made consistentwith the stellar kinematic models. A strong kinematic twist in the gas of NGC2976's center suggests caution, and we advance the mass model based on thestellar kinematics as more reliable. The analysis of this first galaxy showspromising evidence that dark matter halos in late-type dwarfs may in fact bemore consistent with cuspy dark matter distributions than earlier work hasclaimed.

The central dark matter distribution of NGC 2976