%0 Generic %1 micheva2016lyman %A Micheva, Genoveva %A Iwata, Ikuru %A Inoue, Akio K. %D 2016 %K agn escape fraction ionising leakage photons %T Lyman continuum leaking AGN in the SSA22 field %U http://arxiv.org/abs/1604.00102 %X Subaru/SuprimeCam narrowband photometry of the SSA22 field reveals the presence of four Lyman continuum (LyC) candidates among a sample of 14 AGN. Two show offsets and likely have stellar LyC in nature or are foreground contaminants. The remaining two LyC candidates are Type I AGN. We argue that the average LyC escape fraction of high redshift quasars is not likely to be unity, as often assumed in the literature. From direct measurement we obtain the average LyC-to-UV flux density ratio and ionizing emissivity for a number of AGN classes and find it at least a factor of two lower than values obtained assuming f_esc = 1. Comparing to recent Ly\alpha forest measurements, AGNs at redshift z\sim3 make up at most \sim20% and as little as 3% of the total ionizing budget. Our results suggest that AGNs are unlikely to dominate the ionization budget of the Universe at high redshifts.

@misc{micheva2016lyman, abstract = {Subaru/SuprimeCam narrowband photometry of the SSA22 field reveals the presence of four Lyman continuum (LyC) candidates among a sample of 14 AGN. Two show offsets and likely have stellar LyC in nature or are foreground contaminants. The remaining two LyC candidates are Type I AGN. We argue that the average LyC escape fraction of high redshift quasars is not likely to be unity, as often assumed in the literature. From direct measurement we obtain the average LyC-to-UV flux density ratio and ionizing emissivity for a number of AGN classes and find it at least a factor of two lower than values obtained assuming f_esc = 1. Comparing to recent Ly{\alpha} forest measurements, AGNs at redshift z\sim3 make up at most \sim20% and as little as 3% of the total ionizing budget. Our results suggest that AGNs are unlikely to dominate the ionization budget of the Universe at high redshifts.}, added-at = {2016-04-04T11:25:35.000+0200}, author = {Micheva, Genoveva and Iwata, Ikuru and Inoue, Akio K.}, biburl = {https://www.bibsonomy.org/bibtex/252779627fe53d1a5a020e71c56f11920/miki}, description = {[1604.00102] Lyman continuum leaking AGN in the SSA22 field}, interhash = {28fc1bdb0ee7383639d1b6603cef913e}, intrahash = {52779627fe53d1a5a020e71c56f11920}, keywords = {agn escape fraction ionising leakage photons}, note = {cite arxiv:1604.00102Comment: 15 pages, 11 figures; online photometry catalog of AGN in BVRiz, NB359, NB497. Submitted to MNRAS}, timestamp = {2016-04-04T11:25:35.000+0200}, title = {Lyman continuum leaking AGN in the SSA22 field}, url = {http://arxiv.org/abs/1604.00102}, year = 2016 }