%0 Generic %1 blanco2023where %A Blanco, Carlos %A Ghosh, Oindrila %A Jacobsen, Sunniva %A Linden, Tim %D 2023 %K tifr %T Where are the Cascades from Blazar Jets? An Emerging Tension in the $\gamma$-ray sky %U http://arxiv.org/abs/2303.01524 %X Blazars are among the most powerful accelerators and are expected to produce a bright TeV $\gamma$-ray flux. However, TeV $\gamma$-rays are attenuated by interactions with intergalactic radiation before reaching Earth. These interactions produce cascades that transfer the TeV power into the GeV band, powering both extended halos around bright sources and a large contribution to the isotropic $\gamma$-ray background (IGRB). Using state-of-the-art blazar models and recent IGRB measurements, we rule out models where blazars effectively transfer their TeV power into GeV $\gamma$-rays. Three possible solutions include: (1) strong spectral cuts on bright blazars, which are at odds with local blazar observations, (2) collective plasma effects that can prevent the development of blazar cascades, the effectiveness of which is debated, (3) an increase in the effective $\gamma$-ray opacity from axion-like particles.

@misc{blanco2023where, abstract = {Blazars are among the most powerful accelerators and are expected to produce a bright TeV $\gamma$-ray flux. However, TeV $\gamma$-rays are attenuated by interactions with intergalactic radiation before reaching Earth. These interactions produce cascades that transfer the TeV power into the GeV band, powering both extended halos around bright sources and a large contribution to the isotropic $\gamma$-ray background (IGRB). Using state-of-the-art blazar models and recent IGRB measurements, we rule out models where blazars effectively transfer their TeV power into GeV $\gamma$-rays. Three possible solutions include: (1) strong spectral cuts on bright blazars, which are at odds with local blazar observations, (2) collective plasma effects that can prevent the development of blazar cascades, the effectiveness of which is debated, (3) an increase in the effective $\gamma$-ray opacity from axion-like particles.}, added-at = {2023-03-06T06:40:02.000+0100}, author = {Blanco, Carlos and Ghosh, Oindrila and Jacobsen, Sunniva and Linden, Tim}, biburl = {https://www.bibsonomy.org/bibtex/26428e63bb9fcff26b243a1a64fb23cc8/citekhatri}, description = {Where are the Cascades from Blazar Jets? An Emerging Tension in the $\gamma$-ray sky}, interhash = {c9322a72dd44b01ac7f93a7f2be96e7f}, intrahash = {6428e63bb9fcff26b243a1a64fb23cc8}, keywords = {tifr}, note = {cite arxiv:2303.01524}, timestamp = {2023-03-06T06:40:02.000+0100}, title = {Where are the Cascades from Blazar Jets? An Emerging Tension in the $\gamma$-ray sky}, url = {http://arxiv.org/abs/2303.01524}, year = 2023 }