A Textbook Example of a Bow Shock in the Merging Galaxy Cluster 1E 0657–56

By M. Markevitch, Anthony H. Gonzalez, L. David, A. Vikhlinin, S. Murray, W. Forman, C. Jones, W. Tucker. 2001

511 citations recorded by the source corpus.

The Chandra image of the merging, hot galaxy cluster 1E 0657-56 reveals a bow shock propagating in front of a bullet-like gas cloud just exiting the disrupted cluster core. This is the first clear example of a shock front in a cluster. From the jumps in the gas density and temperature at the shock, the Mach number of the bullet-like cloud is 2-3. This corresponds to a velocity of 3000-4000 km s-1 relative to the main cluster, which means that the cloud traversed the core just 0.1-0.2 Gyr ago. The 6-7 keV "bullet" appears to be a remnant of a dense cooling flow region once located at the center of a merging subcluster whose outer gas has been stripped by ram pressure. The bullet's shape indicates that it is near the final stage of being destroyed by ram pressure and gasdynamic instabilities, as the subcluster galaxies move well ahead of the cool gas. The unique simplicity of the shock front and bullet geometry in 1E 0657-56 may allow a number of interesting future measurements. The cluster's average temperature is 14-15 keV but shows large spatial variations. The hottest gas (T > 20 keV) lies in the region of the radio halo enhancement and extensive merging activity involving subclusters other than the bullet.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/6ab519c4865164868e93ebb7cba88cb2cbc46b8e

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Citations in the corpus

X-ray spectroscopy of galaxy clusters: studying astrophysical processes in the largest celestial laboratories (2009, background): “To obtain more quantitative information about the nature of the shock in front of the bullet, (Markevitch et al. 2002) has studied the temperature and density distribution around the region of the shocked ICM in more detail.”
A Dark Core in Abell 520 (2007, background): “…demonstrates the power of such a multiwavelength approach: a 4500 km s−1 cluster collision results in stripping of the gas from the dark matter halo of the smaller cluster, leaving a ≈ 100 kpc projected separation between the gas and lensing mass peaks (Markevitch et al. 2002; Clowe et al. 2004).”
Bow Shock and Radio Halo in the Merging Cluster A520 (2004, background): “Until recently, the only unambiguous cluster merger shock (exhibiting both a sharp gas density edge and a convincing temperature jump, the prerequisites for determining the gas velocity and density jumps) was that found by Chandra in 1E 0657 56 (Markevitch et al. 2002).”
Shock waves in Eulerian cosmological simulations: main properties and acceleration of cosmic rays (2008, unknown): “Journal compilation C© 2009 RAS Downloaded from https://academic.oup.com/mnras/article-abstract/395/3/1333/997891 by guest on 29 July 2018 Sarazin & Vikhlinin 1999; Markevitch et al. 2002; Belsole et al. 2004; Markevitch & Vikhlinin 2007).”
Weak-Lensing Mass Reconstruction of the Interacting Cluster 1E 0657–558: Direct Evidence for the Existence of Dark Matter (2003, methodology): “More recent Chandra and spectroscopic observations further indicate that this merger is nearly in the plane of the sky (Barrena et al. 2002; Markevitch et al. 2002), with the lower mass sub-cluster having recently exited the core of the main cluster (Markevitch et al. 2002).”
XMM-Newton Observations of the Perseus Cluster. I. The Temperature and Surface Brightness Structure (2003, background): “The gas can then start sloshing in the disturbed potential (e.g., Markevitch et al. 2001, 2002).”
NuSTAR OBSERVATIONS OF THE BULLET CLUSTER: CONSTRAINTS ON INVERSE COMPTON EMISSION (2014, background): “The average temperature of the global spectrum is 14.2±0.3 keV, in good agreement with estimates from ROSAT+ASCA (14.5 keV, Liang et al. 2000) and Chandra (14.8 keV, Markevitch et al. 2002), but somewhat higher than independent estimates from XMM-Newton and RXTE (∼ 12 keV, Petrosian et al. 2006).”
Creation of cosmic structure in the complex galaxy cluster merger Abell 2744 (2011, background): “The best-studied example is the Bullet Cluster 1ES 0657-558 (z = 0.296) (Tucker et al. 1998; Markevitch et al. 2002).”
Virial Scaling of Massive Dark Matter Halos: Why Clusters Prefer a High Normalization Cosmology (2007, background): “Popular examples, such as A754 (Henry et al. 2004) and the well-known ‘‘bullet cluster’’ 1E 0657 56 (Markevitch et al. 2002), show multiple peaks in X-ray emission and galaxy number density (Zabludoff & Zaritsky 1995).”
A Direct Empirical Proof of the Existence of Dark Matter (2006, background): “Such high concentrations of dark matter, however, are extremely unlikely based on the measured X-ray plasma temperatures (Markevitch et al. 2002) and cluster galaxy velocity dispersions (Barrena et al. 2002).”
The Bullet Cluster 1E0657-558 evidence shows modified gravity in the absence of dark matter (2007, result): “…value 14.8+1.7−1.2 4.5 1999 ASCA+ROSAT fit 14.5+2.01.7 6.5 1998 ASCA fit 17.4± 2.5 12.3 ture is consistent with the experimental values for the main cluster isothermal temperature, the 1999 ASCA+ROSAT fit, and the 1998 ASCA fit (Markevitch et al., 2002). agreement between theory and experiment.”
Discovery of a Ringlike Dark Matter Structure in the Core of the Galaxy Cluster Cl 0024+17 (2007, background): “…of the cluster suggest that we might not be observing themost violent phase of the collision as in the case of the ‘‘bullet’’ cluster 1E 0657 56 at z ¼ 0:3 (Markevitch et al. 2002), which shows an average temperature of 14Y15 keV with a large spatial variation of temperature and gas density.”
The speed of the ‘bullet’ in the merging galaxy cluster 1E0657−56 (2007, background): “In this system, a massive sub-cluster (the "bullet" withM200 ≃ 1.5× 1014M⊙) has fallen through the main cluster (M200 ≃ 1.5×1015M⊙) on a trajectory nearly exactly in the plane of the sky (Markevitch et al. 2002; Barrena et al. 2002).”