Simultaneous measurements of air showers with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for EeV photon point sources. Several Galactic and extragalactic candidate objects are grouped in classes to reduce the statistical penalty of many trials from that of a blind search and are analyzed for a significant excess above the background expectation. The presented search does not find any evidence for photon emission at candidate sources, and combined p-values for every class are reported. Particle and energy flux upper limits are given for selected candidate sources. These limits significantly constrain predictions of EeV proton emission models from non-transient Galactic and nearby extragalactic sources, as illustrated for the particular case of the Galactic center region.
Publication Source (Journal or Book title)
Astrophysical Journal Letters
Aab, A., Abreu, P., Aglietta, M., Samarai, I., Albuquerque, I., Allekotte, I., Almela, A., Castillo, J., Alvarez-Muñiz, J., Anastasi, G., Anchordoqui, L., Andrada, B., Andringa, S., Aramo, C., Arqueros, F., Arsene, N., Asorey, H., Assis, P., Aublin, J., Avila, G., Badescu, A., Balaceanu, A., Luz, R., Beatty, J., Becker, K., Bellido, J., Berat, C., Bertaina, M., Bertou, X., Biermann, P., Billoir, P., Biteau, J., & Blaess, S. (2017). A Targeted Search for Point Sources of EeV Photons with the Pierre Auger Observatory. Astrophysical Journal Letters, 837 (2) https://doi.org/10.3847/2041-8213/aa61a5