Model-independent redshift estimation of BL Lac objects through very-high-energy observations

Autor:	Zahoor Malik, Sunder Sahayanathan, Zahir Shah, Naseer Iqbal, Aaqib Manzoor, Nilay Bhatt
Rok vydání:	2022
Předmět:	Space and Planetary Science Astrophysics::High Energy Astrophysical Phenomena Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics
Zdroj:	Monthly Notices of the Royal Astronomical Society. 511:994-1003
ISSN:	1365-2966 0035-8711
DOI:	10.1093/mnras/stab3173
Popis:	The very-high-energy (VHE) gamma-ray spectral indices of blazars show a strong correlation with the source redshift. The absence of any such correlation in low-energy gamma-rays and X-rays indicates the presence of extragalactic background light (EBL)-induced absorption of VHE gamma-rays. By employing a linear regression analysis, this observational feature of blazars is used to constrain the redshifts of BL Lac objects that were unknown/uncertain earlier. In addition, we compare the observed VHE spectral index–redshift correlation with those predicted from commonly adopted EBL models. Our study highlights the deviation of EBL-model-based predictions from observations, especially at high redshifts.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4500fa7ba1b8784077e8b341d98bb5de https://doi.org/10.1093/mnras/stab3173 Zobrazit plný text záznamu