arXiv subjects

Matías Gámez-Marín

Publications and source records attributed to Matías Gámez-Marín.

4 recordsLinked to original sources

arXiv2026

A statistical look on kinematic planes of satellite galaxies II: The physics behind their early formation in TNG50 MW/M31-like galaxies

We investigate the physical origin of kinematically persistent planes (KPPs) of satellite galaxies in a sample of 190 Milky Way (MW)/M31-like host-satellite systems drawn from the TNG50 simulation. Building on the identification of 46 early KPPs in a previous work, we analyse their formation in the context of the high-redshift evolution of the local Cosmic Web by tracking the deformation of the so-called Lagrangian Volumes (LVs) surrounding each system. Using a reduced tensor-of-inertia analysis, we characterise the time evolution of the principal directions of collapse and relate them to the clustering of satellite orbital poles. We find that in approximately 67\% of KPPs satellite orbital poles align with the LV direction of strongest collapse, $\vec{e}_3$, while a smaller fraction ($\sim20\%$) align with the intermediate axis, $\vec{e}_2$; alignments with the major axis are rare. These alignments are statistically distinct from random expectations and reflect the confinement of satellites to planar configurations normal to the corresponding LV principal directions. We perform a kinematic analysis of satellite motion within KPPs, finding that vertical and radial motions relative to these KPPs decay early, leading to rotation-dominated, ``disky'' configurations. The characteristic timescales for satellites to settle onto a common orbital plane, for satellite orbital pole clustering, and for LV shape evolution are found to be quasi-coeval, peaking at a Universe age T$_{\rm uni}\sim4$~Gyr, during the fast mass assembly phase of the host halo. These results support a scenario in which early KPPs are fossil remnants of high-redshift, anisotropic mass collapse driven by the local Cosmic Web formation process in $Λ$CDM.

astro-ph.GA↗

arXiv2025

A statistical look on kinematic planes of satellite galaxies I: frequency and properties in TNG50 MW/M31-like galaxies

We use the TNG50 simulation to explore the possible existence of satellite galaxy sets, with fixed-in-time identities, forming kinematically-persistent planes (KPPs) along cosmic time around 190 MW/M31-like galaxies. This is the first study to assess their frequency within the $Λ$CDM framework. We identify KPPs around 46 of these host galaxies, with at least 25\% of their satellites in such configurations. Thereby, KPPs appear more frequent than previously reported, appearing in $\sim24\%$ of MW/M31-like systems, and in $\sim40\%$ of those populated with $N_{\rm sat}\geq9$. We find a dependency of the former frequency on the minimum satellite stellar mass cut, suggesting that it would increase with higher mass resolution. KPP satellite members form a distinct set compared to satellites outside KPPs, located at further distances from the center of their host and maintaining higher specific angular momentum since high redshift. KPP satellites form thin and oblate planes in positional space during long periods of cosmic time. We statistically confirm that KPPs form a kind of backbone of observationally-detected positional planes, and that, in velocity space, KPPs behave as kinematic morphological disks. We show that KPP formation, defined as the time when satellite orbital poles align around a specific, fixed direction (occurring at Universe age $\sim4$ Gyr), predates the end of halo's fast-phase of mass assembly, indicating that halo processes do not drive this clustering. Finally, our results are broadly consistent with the MW's kinematic plane at $z=0$ concerning its morphological properties and degree of satellite orbital poles clustering, mitigating the tension between the existence of these structures and the $Λ$CDM paradigm.

astro-ph.GA↗

arXiv2024

The origin of kinematically-persistent planes of satellite galaxies as driven by the early evolution of the local Cosmic Web in $Λ$CDM

Kinematically-persistent planes of satellites (KPPs) are fixed sets of satellites co-orbiting around their host galaxy, whose orbital poles are conserved and clustered across long cosmic time intervals. They play the role of 'skeletons', ensuring the long-term durability of positional planes. We explore the physical processes behind their formation in terms of the dynamics of the local Cosmic Web (CW), characterized via the so-called Lagrangian Volumes (LVs) built up around two zoom-in, cosmological hydro-simulations of MW-mass disk galaxy + satellites systems, where three KPPs have been identified. By analyzing the LVs deformations in terms of the reduced Tensor of Inertia (TOI), we find an outstanding alignment between the LV principal directions and KPP satellites' orbital poles. The most compressive local mass flows (along the $\hat{e}_3$ eigenvector) are strong at early times, feeding the so-called $\hat{e}_3$-structure, while the smallest TOI axis rapidly decreases. The $\hat{e}_3$-structure collapse marks the end of this regime and is the timescale for the establishment of satellite orbital pole clustering when the Universe is $\lesssim$ 4 Gyr old. KPP proto-satellites aligned with $\hat{e}_3$ are those whose orbital poles are either aligned from early times, or have been successfully bent at $\hat{e}_3$-structure collapse. KPP satellites associated to $\hat{e}_1$ tend to have early trajectories already parallel to $\hat{e}_3$. We show that KPPs can arise as a result of the $Λ$CDM-predicted large-scale dynamics acting on particular sets of proto-satellites, the same dynamics that shape the local CW environment.

astro-ph.GA↗

arXiv2022

Planes of satellites around simulated disk galaxies II: Time-persistent planes of kinematically-coherent satellites in $Λ$CDM

We use two zoom-in $Λ$CDM hydrodynamical simulations of massive disk galaxies to study the possible existence of fixed satellite groups showing a kinematically-coherent behaviour across evolution (angular momentum conservation and clustering). We identify three such groups in the two simulations, defining kinematically-coherent, time-persistent planes (KPPs) that last at least from virialization to $z=0$ (more than 7 Gyrs). This proves that orbital pole clustering is not necessarily set in at low redshift, representing a long-lived property of galaxy systems. KPPs are thin and oblate, represent $\sim25-40\%$ of the total number of satellites in the system, and are roughly perpendicular to their corresponding central disk galaxies during certain periods, consistently with Milky Way $z=0$ data. KPP satellite members are statistically distinguishable from satellites outside KPPs: they show higher specific orbital angular momenta, orbit more perpendicularly to the central disk galaxy, and have larger pericentric distances, than the latter. We numerically prove, for the first time, that KPPs and the best-quality positional planes share the same space configuration across time, such that KPPs act as `skeletons' preventing the latter of being washed out in short timescales. In one of the satellite-host systems, we witness the late capture of a massive dwarf galaxy endowed with its own satellite system, also organized into a KPP configuration prior to its capture. We briefly explore the consequences this event has on the host's KPP, and on the possible enhancement of the asymmetry in the number of satellites rotating in one sense or the opposite within the KPP.

astro-ph.GA↗