Models of Galaxy Clusters with Thermal Conduction

By N. Zakamska, Ramesh Narayan. 2002

184 citations recorded by the source corpus.

We present a simple model of hot gas in galaxy clusters, assuming hydrostatic equilibrium and energy balance between radiative cooling and thermal conduction. For five clusters, A1795, A1835, A2199, A2390, and RX J1347.5-1145, the model gives a good description of the observed radial profiles of electron density and temperature, provided that we take the thermal conductivity κ to be about 30% of the Spitzer conductivity. Since the required κ is consistent with the recent theoretical estimate of Narayan & Medvedev for a turbulent magnetized plasma, we consider a conduction-based equilibrium model to be viable for these clusters. We further show that the hot gas is thermally stable because of the presence of conduction. For five other clusters, A2052, A2597, Hydra A, Ser 159-03, and 3C 295, the model requires unphysically large values of κ to fit the data. These clusters must have some additional source of heat, possibly an active galactic nucleus, since all the clusters have strong radio galaxies at their centers. We suggest that thermal conduction, although not dominant in these clusters, may nevertheless play a significant role by preventing the gas from becoming thermally unstable.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/e941433f69369f4dbee14bf36aaeaad36ace871d

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. A. C. Fabian
2. P. Best
3. Volker Springel
4. P. Hopkins
5. T. Heckman
6. P. Nulsen
7. L. Hernquist
8. B. McNamara

Citations in the corpus

• Hydrodynamical simulations of cluster formation with central AGN heating (2005, background): “…with conduction have been able to provide good matches to observed temperature profiles in some cases (e.g. Voigt et al. 2002; Voigt & Fabian 2003; Zakamska & Narayan 2003), but detailed self-consistent numerical simulations that followed conduction still encountered the coolingflow problem (e.g.…”
• Mechanical feedback from active galactic nuclei in galaxies, groups and clusters (2012, background): “Figure 3 does not include additional power from shocks (David et al 2001), sound waves (Fabian et al 2003a, Forman et al 2005), thermal conduction (Zakamska and Narayan 2003, Voigt and Fabian 2004, Voit 2011), cosmic ray leakage (Mathews and Brighenti 2008) and other forms of energy.”
• High-Resolution X-Ray Spectroscopic Constraints on Cooling-Flow Models for Clusters of Galaxies (2002, background): “Voigt et al. (2002), Zakamska & Narayan (2003), and Fabian, Voigt, & Morris (2002) have demonstrated that the heat flow from the outer regions of clusters with a small suppression (>10 1) in the Spitzer conductivity would appear to cancel radiative losses in many clusters.”
• Buoyancy Instabilities in Weakly Magnetized Low-Collisionality Plasmas (2007, result): “It may thus turn out that thermal conduction from large radii will prove to be less effective than previous authors have suspected (e.g., Bertschinger & Meiksin 1986; Ruszkowski & Begelman 2002; Zakamska & Narayan 2003) at heating “cooling flow” cores in clusters.”
• Filaments, Bubbles, and Weak Shocks in the Gaseous Atmosphere of M87 (2006, background): “Suggestions for heating include thermal conduction (e.g., Tucker & Rosner 1983; Bertschinger & Meiksin 1986; Gaetz 1989; David et al. 1992; Zakamska & Narayan 2003; Voigt & Fabian 2004) and cluster mergers (e.g., Fujita et al. 2004; but see Böhringer et al. 2004).”
• What is a cool-core cluster? a detailed analysis of the cores of the X-ray flux-limited HIFLUGCS cluster sample (2009, background): “Among those mechanisms proposed are: conduction (e.g. Zakamska & Narayan 2003), central AGN heating via direct cosmic ray-ICM interaction+conduction (Guo & Oh 2008), AGN heating by bubble induced weak shocks (e.g. Mathews et al. 2006), soundwaves+conduction (e.g. Ruszkowski et al. 2004) and…”
• On the prevalence of radio‐loud active galactic nuclei in brightest cluster galaxies: implications for AGN heating of cooling flows (2006, background): “…process to provide this is thermal conduction, which will work to transport energy from the reservoir of hot gas outside the cooling radius down into the cooler cluster centre (e.g. Narayan & Medvedev 2001; Voigt et al. 2002; Zakamska & Narayan 2003; Voigt & Fabian 2004, and references therein).”
• Gravitational quenching in massive galaxies and clusters by clumpy accretion (2007, background): “This implies that if the conductivity is as high as fs ∼ 0.2 (e.g. Zakamska & Narayan 2003), it would limit the mass range of effective clumps that could form by thermal instability inside virialized haloes of ∼ 1013M⊙ to mc ∼ 107−8M⊙.”
• Feedback heating by cosmic rays in clusters of galaxies (2007, methodology): “…temperature and density profiles profiles differs from cluster to cluster, and a physical explanation of how f self-adjusts in each cluster is missing; furthermore, a significant fraction of observed clusters cannot be fit at all by conduction only models with f 6 1 (Zakamska & Narayan 2003).”
• X-ray Spectroscopy of Cooling Clusters (2005, methodology): “Comparison with the data initially looked promising (Zakamska & Narayan 2003; Voigt et al. 2002) then under further inspection ruled it out (Kim & Narayan 2003a; Voigt & Fabian 2004).”
• STIRRING UP THE POT: CAN COOLING FLOWS IN GALAXY CLUSTERS BE QUENCHED BY GAS SLOSHING? (2009, background): “…reconnection (Soker & Sarazin 1990), thermal conduction due to electron collisions (e.g., Narayan & Medvedev 2001; Fabian, Voigt, & Morris 2002; Zakamska & Narayan 2003) and turbulent conduction (e.g., Cho et al. 2003; Voigt & Fabian 2004), and heating by cosmic rays (e.g., Colafrancesco &…”
• A deep Chandra observation of the Perseus cluster: shocks and ripples (2003, background): “…and bubbles may heat the surrounding gas from the centre (Brüggen & Kaiser 2001; Quilis, Bower & Balogh 2001; Reynolds, Heinz & Begelman 2001; Basson & Alexander 2003) or thermal conduction may heat it from the outside (Voigt et al. 2002; Fabian, Voigt & Morris 2002c; Zakamska & Narayan 2003).”
• Thermal instability and the feedback regulation of hot haloes in clusters, groups and galaxies (2011, background): “Energetically, there are a number of heating sources that can in principle balance cooling in hot halos: e.g., thermal conduction in clusters (e.g., Zakamska & Narayan 2003), the kinetic energy of galaxies and mini-halos (e.g., Kim, El-Zant, & Kamionkowski 2005; Dekel & Birnboim 2008), and the…”
• FEEDBACK IN LUMINOUS OBSCURED QUASARS (2011, background): “…to the gas remains uncertain (e.g., Bîrzan et al. 2004; Best et al. 2005; Heinz et al. 2006), as does the relative importance of heating by the active nucleus as opposed to other possible sources (e.g., Zakamska & Narayan 2003; Sijacki et al. 2008; Conroy & Ostriker 2008; Parrish et al. 2009).”
• Heating Hot Atmospheres with Active Galactic Nuclei (2007, background): “…and radiation (the fine-tuning problem; Stewart et al. 1984; Malagoli et al. 1987; Bregman & David 1988), there are several clusters where heat conduction cannot balance cooling throughout the core, even at the full Braginskii rate (Zakamska & Narayan 2003; Voigt & Fabian 2004; Wise et al. 2004).”