Temperature map of the Coma Cluster of galaxies

We present a temperature map of the Coma Cluster of galaxies with an angular resolution of 8′ corresponding to 320 kpc (H₀ = 50 km s^-1 Mpc^-1) and an angular extent of 1°.5. The temperature was derived from the hardness ratio of two energy bands, 0.5-3 and 3-10 keV. The X-ray image in the 0.5 10 keV band was also deconvolved from the observed data with the angular resolution of 2′. We have refined the complex response function of the ASCA telescope, taking into account the off-axis angle and the energy of incident X-rays in this analysis. The temperature map indicates that a hot region (kT = 11-14 keV) is largely extended to the northwest 15′-40′ off from the cluster center, while a cool region (kT ∼ 5 keV) is 20′ off to the southeast. Another cool region is identified with the subcluster associated with the cD galaxy NGC 4839. These observational features can be interpreted in the context of the subcluster-cluster merging.