1E 1415.6+2557: an X-Ray--Selected BL Lacertae Object in a Luminous Galaxy
Abstract
The identification of a fifth serendipitous Einstein source with a new BL Lac object in a very luminous galaxy is reported. The resolved component is well fitted by an exponential disk with scale length 18 kpc and absolute magnitude of roughly -24.2. A redshift of 0.237 is derived from stellar absorption features. No emission lines are seen in the 3200-9000 A wavelength range. Decomposition of the optical spectrum into a standard galaxy plus a power law yields a spectral index of 0.5 + or - 0.5, significantly flatter than in the average BL Lac object. Linear polarization of the nonstellar component is about 6 percent in the 4500-7000 A wavelength range. The X-ray flux in the 0.3-3.5 keV band is 1.16 x 10 to the -11th ergs/sq cm/s, corresponding to a luminosity of 3.5 x 10 to the 45th ergs/s . The radio flux density is 85.6 mJy at 20 cm and 54.5 mJy at 6 cm.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1986
- DOI:
- 10.1086/164032
- Bibcode:
- 1986ApJ...302..711H
- Keywords:
-
- Bl Lacertae Objects;
- X Ray Sources;
- Linear Polarization;
- Polarimetry;
- Radiant Flux Density;
- Radio Emission;
- Visible Spectrum;
- Astrophysics;
- BL LACERTAE OBJECTS;
- POLARIZATION;
- X-RAYS: SOURCES