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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present a dynamical analysis to infer the structural parameters andproperties of the two nearby, compact, high velocity dispersion galaxiesMRK1216 & NGC1277. Combining deep HST imaging, wide-field IFU stellarkinematics, and complementary long-slit spectroscopic data out to 3 R_e, weconstruct orbit-based models to constrain their black hole masses, dark mattercontent and stellar mass-to-light ratios. We obtain a black hole mass oflog(Mbh/Msun) = 10.1(+0.1/-0.2) for NGC1277 and an upper limit of log(Mbh/Msun)= 10.0 for MRK1216, within 99.7 per cent confidence. The stellar mass-to-lightratios span a range of Upsilon_V = 6.5(+1.5/-1.5) in NGC1277 and Upsilon_H =1.8(+0.5/-0.8) in MRK1216 and are in good agreement with SSP models of a singlepower-law Salpeter IMF. Even though our models do not place strong constraintson the dark halo parameters, they suggest that dark matter is a necessaryingredient in MRK1216, with a dark matter contribution of 22(+30/-20) per centto the total mass budget within 1 R_e. NGC1277, on the other hand, can bereproduced without the need for a dark halo, and a maximal dark matter fractionof 13 per cent within the same radial extent. In addition, we investigate theorbital structures of both galaxies, which are rotationally supported andconsistent with photometric multi-S\'ersic decompositions, indicating thatthese compact objects do not host classical, non-rotating bulges formed duringrecent (z <= 2) dissipative events or through violent relaxation. Finally, bothMRK 1216 and NGC 1277 are anisotropic, with a global anisotropy parameter deltaof 0.33 and 0.58, respectively. While MRK 1216 follows the trend offast-rotating, oblate galaxies with a flattened velocity dispersion tensor inthe meridional plane of the order of beta_z = delta, NGC 1277 is highlytangentially anisotropic and seems to belong kinematically to a distinct classof objects.

MRK 1216 & NGC 1277 - An orbit-based dynamical analysis of compact, high velocity dispersion galaxies