Recent observations of galaxy clusters and groups with misalignments between their central AGN jets and X-ray cavities, or with multiple misaligned cavities, have raised concerns about the jet - bubble connection in cooling cores, and the processes responsible for jet realignment. To investigate the frequency and causes of such misalignments, we construct a sample of 16 cool core galaxy clusters and groups. Using VLBA radio data we measure the parsec-scale position angle of the jets, and compare it with the position angle of the X-ray cavities detected in Chandra data. Using the overall sample and selected subsets, we consistently find that there is a 30% - 38% chance to find a misalignment larger than $\Delta\Psi = 45^{\circ}$ when observing a cluster/group with a detected jet and at least one cavity. We determine that projection may account for an apparently large $\Delta\Psi$ only in a fraction of objects ($\sim$35%), and given that gas dynamical disturbances (as sloshing) are found in both aligned and misaligned systems, we exclude environmental perturbation as the main driver of cavity - jet misalignment. Moreover, we find that large misalignments (up to $\sim90^{\circ}$) are favored over smaller ones ($45^{\circ}\leq\Delta\Psi\leq70^{\circ}$), and that the change in jet direction can occur on timescales between one and a few tens of Myr. We conclude that misalignments are more likely related to actual reorientation of the jet axis, and we discuss several engine-based mechanisms that may cause these dramatic changes.

Francesco Ubertosi, Gerrit Schellenberger, Ewan O'Sullivan, Jan Vrtilek, Simona Giacintucci, Laurence P. David, et al. (2024). Jet Reorientation in Central Galaxies of Clusters and Groups: Insights from VLBA and Chandra Data. THE ASTROPHYSICAL JOURNAL, 961(1), 1-19 [10.3847/1538-4357/ad11d8].

Jet Reorientation in Central Galaxies of Clusters and Groups: Insights from VLBA and Chandra Data

Francesco Ubertosi
Writing – Original Draft Preparation
;
Myriam Gitti
Supervision
;
Fabrizio Brighenti
2024

Abstract

Recent observations of galaxy clusters and groups with misalignments between their central AGN jets and X-ray cavities, or with multiple misaligned cavities, have raised concerns about the jet - bubble connection in cooling cores, and the processes responsible for jet realignment. To investigate the frequency and causes of such misalignments, we construct a sample of 16 cool core galaxy clusters and groups. Using VLBA radio data we measure the parsec-scale position angle of the jets, and compare it with the position angle of the X-ray cavities detected in Chandra data. Using the overall sample and selected subsets, we consistently find that there is a 30% - 38% chance to find a misalignment larger than $\Delta\Psi = 45^{\circ}$ when observing a cluster/group with a detected jet and at least one cavity. We determine that projection may account for an apparently large $\Delta\Psi$ only in a fraction of objects ($\sim$35%), and given that gas dynamical disturbances (as sloshing) are found in both aligned and misaligned systems, we exclude environmental perturbation as the main driver of cavity - jet misalignment. Moreover, we find that large misalignments (up to $\sim90^{\circ}$) are favored over smaller ones ($45^{\circ}\leq\Delta\Psi\leq70^{\circ}$), and that the change in jet direction can occur on timescales between one and a few tens of Myr. We conclude that misalignments are more likely related to actual reorientation of the jet axis, and we discuss several engine-based mechanisms that may cause these dramatic changes.
2024
Francesco Ubertosi, Gerrit Schellenberger, Ewan O'Sullivan, Jan Vrtilek, Simona Giacintucci, Laurence P. David, et al. (2024). Jet Reorientation in Central Galaxies of Clusters and Groups: Insights from VLBA and Chandra Data. THE ASTROPHYSICAL JOURNAL, 961(1), 1-19 [10.3847/1538-4357/ad11d8].
Francesco Ubertosi; Gerrit Schellenberger; Ewan O'Sullivan; Jan Vrtilek; Simona Giacintucci; Laurence P. David; William Forman; Myriam Gitti; Tiziana ...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/961827
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