86 citations · 814 across the 38 of their papers we have counts for
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HALO II: Constraining Hubble constant through continuum delay fitting of Fairall 9
Amit Kumar Mandal, Francisco Pozo Nuñez, Vikram Kumar Jaiswal +28
The Hubble tension remains one of the most significant unresolved problems in modern cosmology. A key question is whether it may arise from underestimated systematic uncertainties…
Consistency between X-ray and UV-Optical reverberation measurements in NGC 5548
Amit Kumar Mandal, Bożena Czerny, Michal Dovčiak +2
The hard X-rayemitting hot corona is a key component of active galaxies. Constraints on the hot corona height can be derived from reverberation studies in both the X-ray and opt…
HALO I: Photometric continuum reverberation mapping of Fairall 9
Amit Kumar Mandal, Francisco Pozo Nuñez, Vikram Kumar Jaiswal +23
We investigate the origin of inter-band continuum time delays in active galactic nuclei (AGNs) to study the structure and properties of their accretion disks. We aim to measure the…
Frequency-resolved time lags due to X-ray disk reprocessing in AGN
Christos Panagiotou, Iossif Papadakis, Erin Kara +6
Over the last years, a number of broadband reverberation mapping campaigns have been conducted to explore the short-term UV and optical variability of nearby AGN. Despite the exten…
X-ray reverberation modelling of the continuum, optical/UV time-lags in quasars
D. A. Langis, I. E. Papadakis, E. Kammoun +2
Context: Extensive, multi-wavelength monitoring campaigns of nearby and higher redshift active galactic nuclei (AGN) have shown that the UV/optical variations are well correlated w…
Uncovering the geometry of the hot X-ray corona in the Seyfert galaxy NGC4151 with IXPE
V. E. Gianolli, D. E. Kim, S. Bianchi +106
We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy NGC4151. The source has been observed with the Imaging X-ray Polarimetry Explorer (IXPE) for 700 ks,…
Multiwavelength power-spectrum analysis of NGC 5548
Christos Panagiotou, Iossif Papadakis, Elias Kammoun +1
NGC 5548 was recently monitored intensively from NIR to X-rays as part of the STORM campaign. Its disc emission was found to lag behind the observed X-rays, while the measured time…