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Intensive broadband reverberation mapping (IBRM) campaigns have shown that AGN variability is significantly more complex than expected from disc reverberation of the variable X-ray illumination. The UV/optical variability is highly correlated and lagged, with longer lag at longer wavelength, but the timescale is longer than expected. More challenging though is that the UV/optical lightcurves are not well correlated with the X-rays which were meant to be driving them. Instead, we consider an intrinsically variable accretion disc, where mass accretion rate fluctuations propagate in through the flow, modulating the intrinsically faster X-ray variability from the central regions. We match our model to the parameters of Fairall 9, a well studied AGN with $L\sim 0.1L_{\mathrm{Edd}}$, where the spectrum is dominated by the UV/EUV rather than the X-rays. We show that intrinsic variability and propagation gives X-ray and UV/optical light-curves that are dominated by variability on two different time-scales, yet are correlated on long time-scales. We include reprocessing of the X-rays from the disc but this has negligible impact on the lightcurves for spectra where the EUV dominates the bolometric power. We also include reverberation of the total (EUV plux X-ray) variable spectrum off a wind. This results in a bound-free component which predominantly follows the slow variable EUV, but lagged and smoothed on the light-travel time. This spectrum is redder than the EUV disc emission, so it contributes more at longer wavelengths giving the apparent rise in lag time with wavelength from a constant lag component. We conclude that contrary to the original motivation for IBRM campaigns, AGN variability is likely driven by intrinsic fluctuations within the disc, not X-ray reprocessing, and that the observed lags are produced by the EUV illumination of the wind not the X-ray illumination of the disc., Comment: 15 Pages, 10 Figures, 1 Appendix - Submitted to MNRAS (on 22 Dec. 2023)

Accretion disc model fitting to optical/UV quasar spectra requires that the highest mass black holes have the highest spin, with implications on the hierarchical growth of supermassive black holes and their host galaxies over cosmic time. However, these accretion disc models did not include the effects of relativistic ray tracing. Here we show that gravitational redshift cancels out most of the increase in temperature and luminosity from the smaller radii characteristic of high spin. Disc models which include the self consistent general relativistic ray tracing do not fit the UV spectra of the most massive quasars ($\log M/M_{\odot} \geq 9.5$), most likely showing that the disc structure is very different to that assumed. We extend the relativistic ray tracing on more complex disc models, where the emission is not limited to (colour temperature corrected) black body radiation but can instead be emitted as warm and hot Comptonisation. We demonstrate this on the broadband (UV/X-ray) spectrum of Fairall 9, a local intensively monitored 'bare' AGN (no significant intrinsic cold or warm absorption). We show that including relativistic corrections does make a difference even to these more complex models, but caution that the inferred black hole spin depends on the assumed nature and geometry of the accretion flow. Additionally, we make our model code publicly available, and name it RELAGN., Comment: 10 Pages, 6 Figures, 4 Appendices. Accepted to MNRAS

[Abridged] The X-ray broadband spectra of the bare AGN Mrk 110, obtained by simultaneous XMM-Newton and NuSTAR observations (Nov 2019 and April 2020), are characterised by the presence of a prominent and absorption-free smooth soft X-ray excess, moderately broad OVII and Fe Kalpha emission lines, and a lack of a strong Compton hump. While relativistic reflection as the sole emission is ruled out, a simplified combination of soft and hard Comptonisation from a warm and a hot coronae, plus mild relativistic disc reflection reproduces the data very well. We aim to confirm the physical origin of the soft X-ray excess of Mrk 110 and to determine its disc-corona system properties from its energetics using two new sophisticated models: reXcor and relagn, respectively. At both epochs, the inferred high-values of the warm-corona heating from the X-ray broadband spectral analysis using reXcor confirm that the soft X-ray excess originates mainly from a warm corona rather than relativistic reflection. The intrinsic best-fit SED determined at both epochs using relagn show a high X-ray contribution relative to the UV and are very well reproduced by a warm and hot coronae plus mild relativistic reflection. The outer radii of the hot and warm coronae are located at a few 10s and ~100 Rg, respectively. Moreover, combining the inferred low Eddington ratio (~ a few %) from this work, and previous multi-wavelength spectral and timing studies suggests that Mrk 110 could be classified as a moderate changing-state AGN. Our analysis confirms the existence of a warm corona as a significant contribution to the soft X-ray excess and UV emission in Mrk 110, adding to growing evidence that AGN accretion deviates from standard disc theory. This strengthens the importance of long-term multi-wavelength monitoring on both single targets and large AGN surveys to reveal the real nature of disc-corona system in AGN., Comment: 12 pages, 7 figures, accepted for publication in A&A

Continuum reverberation mapping of AGN can provide new insight into the nature and geometry of the accretion flow. Some of the X-rays from the central corona irradiating the disc are absorbed, increasing the local disc temperature. This gives an additional re-processed contribution to the spectral energy distribution (SED) which is lagged and smeared relative to the driving X-ray light-curve. We directly calculate this reverberation from the accretion disc, creating fully time dependent SEDs for a given X-ray light-curve. We apply this to recent intensive monitoring data on Fairall 9, and find that it is not possible to produce the observed UV variability by X-ray reprocessing of the observed light-curve from the disc. Instead, we find that the majority of the variability must be intrinsic to the UV emission process, adding to evidence from changing look AGN that this region has a structure which is quite unlike a Shakura-Sunyaev disc. We filter out this long timescale variability and find that reprocessing alone is still insufficient to explain even the fast variability in our assumed geometry of a central source illuminating a flat disc. The amplitude of reprocessing can be increased by any vertical structure such as the BLR and/or an inner disc wind, giving a better match. Fundamentally though the model is missing the major contributor to the variability, intrinsic to the UV/EUV emission rather than arising from reprocessing., Comment: 14 pages, 11 figures, 4 appendices. Accepted for publication MNRAS

We use the SOUX sample of $\sim$700 AGN to form average optical-UV-X-rays SEDs on a 2D grid of $M_{\mathrm{BH}}$ and $L_{2500}$. We compare these with the predictions of a new AGN SED model, QSOSED, which includes prescriptions for both hot and warm Comptonisation regions as well as an outer standard disc. This predicts the overall SED fairly well for 7.5

The long-term goal of this partnership is to establish an operational forecasting system of the wind field and resulting waves and surge impacting the coastline during the approach and landfall of tropical cyclones. The results of this forecasting system would provide real-time information to the National Hurricane Center during the tropical cyclone season in the Atlantic for establishing improved advisories for the general public and federal agencies including military and civil emergency response teams., Prepared in cooperation with RSMAS Applied Marine Physics, University of Miami, Florida, the Civil and Coastal Engineering Department, University of Florida, Gainesville, Civil & Environmental Engineering, University of Central Florida, Orlando, The Johns Hopkins University, Applied Physics Laboratory, Laurel, MD, NOAA/AOML, Hurricane Research Division, Miami, FL, DOC/NOAA/NWS-Eastern Region, Eastern Region Headquarters, Bohemia, NY and Oceanweather, Inc., Cos Cob, CT. The original document contains color images.

The long-term goal of this partnership is to establish an operational forecasting system of the wind field and resulting waves and surge impacting the coastline during the approach and landfall of tropical cyclones The results of this forecasting system would provide real-time information to the National Hurricane Center during the tropical cyclone season in the Atlantic for establishing improved advisories for the general public and federal agencies including military and civil emergency response teams.

The long-term goal of this partnership is to establish an operational forecasting system of the wind field and resulting waves and surge impacting the coastline during the approach and landfall of tropical cyclones. The results of this forecasting system would provide real-time information to the National Hurricane Center during the tropical cyclone season in the Atlantic for establishing improved advisories for the general public and federal agencies including military and civil emergency response teams., A National Oceanographic Partnership Program Award. The original document contains color images.

The long-term goal of this partnership is to establish an operational forecasting system of the wind field and resulting waves and surge impacting the coastline during the approach and landfall of tropical cyclones. The results of this forecasting system would provide real-time information to the National Hurricane Center during the tropical cyclone season in the Atlantic for establishing improved advisories for the general public and federal agencies including military and civil emergency response teams. Objectives: (1) To define output products necessary to enhance the guidance skills of the Tropical Cyclone Forecast/Advisory product. (2) To test the model infra-structure that would lead toward better forecast information for landfall hurricane wind, wave, and surge conditions. Several historical storms will be used to assess model infra-structure. (3) To develop the interface that couples high-resolution cyclone wind fields to the selected wind model. (4) To develop a system that couples storm surge and spectral wave models driven by winds specified in 6). (5) Test entire system via a proof-of-concepts approach with data from several historical hurricanes. (6) Test system in semi-operational mode during several hurricane seasons and begin transition to fully operational mode., A National Oceanographic Partnership Program Award. Prepared in cooperation with Civil and Coastal Engineering Department, University of Florida, Gainesville, FL; Civil & Environmental Engineering, University of Central Florida, Orlando, FL; The Johns Hopkins University, Applied Physics Laboratory, Laurel, MD; USAEWES, Coastal and Hydraulics Laboratory, Research Division, Vicksburg, MS; NOAA/AOML, Hurricane Research Division, Miami, FL; DOC/NOAA/NWS-Eastern Region, Bohemia, NY; Oceanweather, Inc., Cos Cob, CT; Gigantic Computer Services, Inc., Miami, FL; Advance Computing Technology Center (ACTC), T.J. Watson Research Center, International Business Machines Co., St. Paul, MN. The original document contains color images

The long-term goal of this partnership is to establish an operational forecasting system of the wind field and resulting waves and surge impacting the coastline during the approach and landfall of tropical cyclones. The results of this forecasting system would provide real-time information to the National Hurricane Center during the tropical cyclone season in the Atlantic for establishing improved advisories for the general public and federal agencies including military and civil emergency response teams., A National Oceanographic Partnership Program Award. The original document contains color images.