Scattering of emission lines in galaxy cluster cores: measuring electron temperature

Abstract

The central galaxies of some clusters can be strong emitters in the Ly$\alpha$ and H$\alpha$ lines. This emission may arise either from the cool/warm gas located in the cool core of the cluster or from the bright AGN within the central galaxy. The luminosities of such lines can be as high as $10^{42}-10^{44}$ erg/s. This emission originating from the core of the cluster will get Thomson scattered by hot electrons of the intra-cluster medium (ICM) with an optical depth $\sim$ 0.01 giving rise to very broad ($\Delta \lambda /\lambda \sim$ 15%) features in the scattered spectrum. We discuss the possibility of measuring the electron density and temperature using information on the flux and width of the highly broadened line features.

9 pages, 5 figures, accepted in MNRAS

References in corpus (6)

• An Observational Determination of the Bolometric Quasar Luminosity Function
• Intracluster Medium Entropy Profiles for a Chandra Archival Sample of Galaxy Clusters
• The ghost of a dwarf galaxy: fossils of the hierarchical formation of the nearby spiral galaxy NGC 5907
• Resurrecting the Red from the Dead: Optical Properties of BCGs in X-ray Luminous Clusters
• An optical spectroscopic survey of the 3CR sample of radio galaxies with z<0.3. I. Presentation of the data
• Ionized nebulae surrounding brightest cluster galaxies