Artículo
Abstract:
We propose that some of the high-latitude unidentified EGRET γ-ray sources could be the result of gravitational lensing amplification of the innermost regions of distant, faint, active galactic nuclei. These objects have γ-ray-emitting regions small enough to be affected by microlensing of stars in interposed galaxies. We compute the gravitational amplification, taking into account effects of the host galaxy of the lens, and prove that, whereas the innermost γ-ray regions can be magnified up to a thousand times, there is no amplification at radio frequencies, which leads to the observed absence of strong counterparts. Some new effects in the spectral evolution of a gravitational microlensed γ-ray active galactic nuclei are predicted. Within a reasonable range of lensing parameters and/or types of sources, both variable and nonvariable EGRET detections at high latitudes can be explained by microlensing. The same phenomenon could also have an important incidence among the future GLAST detections at high latitudes.
Registro:
| Documento: | Artículo |
| Título: | Gravitational lensing as a possible explanation for some unidentified gamma-ray sources at high latitudes |
| Autor: | Torres, D.F.; Romero, G.E.; Eiroa, E.F. |
| Filiación: | Joseph Henry Laboratories, Jadwin Hall, Princeton University, P.O. Box 708, Princeton, NJ 08544-0708, United States Inst. Argentine Radioastronomia, Casilla de Correo Number 5, 1894 Buenos Aires, Argentina Inst. de Astron./Fis. del Espacio, Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires, Argentina |
| Palabras clave: | Galaxies: active; Gamma rays: observations; Gravitational lensing |
| Año: | 2002 |
| Volumen: | 569 |
| Número: | 2 I |
| Página de inicio: | 600 |
| Página de fin: | 604 |
| DOI: | http://dx.doi.org/10.1086/339348 |
| Título revista: | Astrophysical Journal |
| Título revista abreviado: | Astrophys. J. |
| ISSN: | 0004637X |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v569_n2I_p600_Torres |
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Citas:
---------- APA ----------
Torres, D.F., Romero, G.E. & Eiroa, E.F. (2002) . Gravitational lensing as a possible explanation for some unidentified gamma-ray sources at high latitudes. Astrophysical Journal, 569(2 I), 600-604.http://dx.doi.org/10.1086/339348
---------- CHICAGO ----------
Torres, D.F., Romero, G.E., Eiroa, E.F. "Gravitational lensing as a possible explanation for some unidentified gamma-ray sources at high latitudes" . Astrophysical Journal 569, no. 2 I (2002) : 600-604.http://dx.doi.org/10.1086/339348
---------- MLA ----------
Torres, D.F., Romero, G.E., Eiroa, E.F. "Gravitational lensing as a possible explanation for some unidentified gamma-ray sources at high latitudes" . Astrophysical Journal, vol. 569, no. 2 I, 2002, pp. 600-604.http://dx.doi.org/10.1086/339348
---------- VANCOUVER ----------
Torres, D.F., Romero, G.E., Eiroa, E.F. Gravitational lensing as a possible explanation for some unidentified gamma-ray sources at high latitudes. Astrophys. J. 2002;569(2 I):600-604.http://dx.doi.org/10.1086/339348
