Investigating the Infrared Properties of Candidate Blazars

[摘要] Blazars are active galaxies with super-massive black holes, containing jets that accelerate plasma material and produce radiation. They are unique among other active galaxies for properties such as rapid variability and the lack of emission lines. The double-peaked spectral energy distribution (SED) found for most blazar objects suggests that synchrotron radiation and Compton scattering occurs in the jets. This study is an investigation of the infrared (IR) spectra of a selected population of blazar candidates, focusing on the IR properties of objects within the three types of blazars currently recognized by their spectral characteristics at other wavelengths. Using blazar candidates found in a recent study of the northern sky (Sowards-Emmerd et al., The Astrophysical Journal, 2005), IRAS data for 12, 25, 60, and 100 {micro}m, as well as any available data from 2MASS and EGRET, were located. The synchrotron peak of the SED of each object was expected to occur anywhere in the infrared (IR) to soft X-ray range. However, peaks were generally found to lie in the IR range, suggesting potential selection biases. An analysis of selection techniques reveals that the figure of merit used in the original survey is engineered to select objects with a Compton scattering peak luminosity occurring in the GeV range, the energy band most easily detected by the upcoming GLAST mission. Therefore, this figure of merit selection process should be used to compile a list of blazar candidates for further study in anticipation of the launch of the satellite.

[发布日期] 2005-12-15 [发布机构] Stanford Linear Accelerator Center

[关键词] Spectra;Energy Spectra;Luminosity;43 Particle Accelerators;Galaxies