Projected Kinematic Anisotropy and Velocity-Dispersion Gradients in Galactic Globular Clusters: An Interval-Defined Framework from HST Proper Motions

Clicks: 7
ID: 327878
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #882 of 1,039 articles by views in monthly notices of the royal astronomical society

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 1,039 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Abstract We present an interval-defined framework for summarising projected internal kinematics in globular clusters (GCs) using the Global Kinematic Anisotropy Parameter (KAP), the Global Kinematic Index (GKI), and the raw and noise-aware profile-scatter diagnostics Ds and $D_{s,\rm corr}$. KAP is a variance-weighted ratio of projected radial–tangential squared-dispersion contrasts, whereas GKI is the empirical outward logarithmic slope of the combined velocity-dispersion profile over a specified radial interval. We apply the framework to homogeneous HST/HACKS proper-motion profiles for 20 Galactic GCs. Within the primary normalized interval R ≤ Rh, l, five clusters satisfy the radial-KAP criterion, fifteen are consistent with zero net projected KAP contrast, and none satisfies the tangential criterion. Over the full available HST range, seven clusters satisfy the radial-KAP criterion and thirteen are consistent with zero net projected KAP contrast; NGC 6388 and NGC 6441 account for the two interval-dependent class changes. Eighteen clusters have significantly negative GKI within R ≤ Rh, l, while NGC 5927 and NGC 6441 are consistent with flat empirical profiles. Eleven clusters have $D_{s,\rm corr}=0$, and nine retain non-zero corrected scatter. KAP and GKI are radial-interval-dependent observational summaries, while Ds and $D_{s,\rm corr}$ only identify profiles requiring bin-level inspection. A negative GKI over the broader HST interval is not specific to an intermediate-mass black hole, and unresolved spheres of influence cannot be excluded by these binned profiles. Analytic uncertainty propagation, parametric resampling, leave-one-bin-out tests, and controlled synthetic experiments support the internal consistency of the framework under the conditions examined.
Reference Key
openalex_W7211879378 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors S J Turaev, S N Nuritdinov, Q X Yuldoshev
Journal monthly notices of the royal astronomical society
Year 2026
DOI
10.1093/mnras/stag1659
URL
https://doi.org/10.1093/mnras/stag1659
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.