Tomographic constraints on the high-energy cosmic neutrino emission rate

Monthly Notices of the Royal Astronomical Society Oxford University Press 546:3 (2026) stag084

Authors:

Alberto Gálvez Ureña, Federico Urban, David Alonso

Abstract:

Despite growing efforts to find the sources of high-energy neutrinos measured by IceCube, the bulk of the neutrinos remain with unknown origins. In this work, we aim to constrain the emissivity of cosmic high-energy neutrinos from extragalactic sources through their correlation with the large-scale structure. We use cross-correlations between the IceCube 10-year data set and tomographic maps of the galaxy overdensity to place constraints on the bias-weighted high-energy neutrino emissivity out to redshift . We test two different models to describe the evolution of neutrino emissivity with redshift, a power-law model , and a model tracking the star formation history, assuming a simple power-law model for the energy injection spectrum. We also consider a non-parametric reconstruction of the astrophysical neutrino emissivity as a function of redshift. We do not find any significant correlation, with our strongest results corresponding to a deviation with respect to a model with zero signal. We use our measurements to place upper bounds on the bias-weighted astrophysical high-energy neutrino emission rate as a function of redshift for different source models. This analysis provides a new probe to test extragalactic neutrino source models. With future neutrino and galaxy data sets, we expect the constraining and detection power of this type of analysis to increase.

Exploring the quasar disc-wind-jet connection with LoTSS and SDSS

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2026) stag065

Authors:

Charlotte L Jackson, James H Matthews, Imogen H Whittam, Matt J Jarvis, Matthew J Temple, Amy L Rankine, Paul C Hewett

Abstract:

Abstract We investigate the relationship between disc winds, radio jets, accretion rates and black hole masses of a sample of ∼100k quasars at z ≈ 2. Combining spectra from the 17th data release of the Sloan Digital Sky Survey (SDSS) with radio fluxes from the 2nd data release of the Low Frequency ARray (LOFAR) Two-Meter Sky Survey (LoTSS), we statistically characterise a radio loud and radio quiet population using a two-component Gaussian Mixture model, and perform population matching in black hole mass and Eddington fraction. We determine how the fraction of radio loud sources changes across this parameter space, finding that jets are most efficiently produced in quasars with either a very massive central black hole (MBH > 109M⊙) or one that is rapidly accreting (λEdd > 0.3). We also show that there are differences in the blueshift of the $\textrm {C}\, \rm \small {IV}$ λ1549Å line and the equivalent width of the $\rm {He}\, \rm \small {II}$ λ1640Å line in radio loud and radio quiet quasars that persist even after accounting for differences in the mass and accretion rate of the central black hole. Generally, we find an anti-correlation between the inferred presence of disc winds and jets, which we suggest is mediated by differences in the quasars’ spectral energy distributions. The latter result is shown through the close coupling between tracers of wind kinematics and the ionising flux– which holds for both radio loud and radio quiet sources, despite differences between their emission line properties– and is hinted at by a different Baldwin effect in the two populations.

Cosmic rays, gamma rays and neutrinos from discrete black hole X-ray binary ejecta

(2026)

Authors:

Nicolas J Bacon, Alex J Cooper, Dimitrios Kantzas, James H Matthews, Rob Fender

Publisher Correction: Evidence of mutually exclusive outflow forms from a black hole X-ray binary

Nature Astronomy Springer Nature (2026) 1-2

Authors:

Zuobin Zhang, Jiachen Jiang, Francesco Carotenuto, Honghui Liu, Cosimo Bambi, Rob P Fender, Andrew J Young, Jakob van den Eijnden, Christopher S Reynolds, Andrew C Fabian, Julien N Girard, Joey Neilsen, James F Steiner, John A Tomsick, Stéphane Corbel, Andrew K Hughes

Stellar-mass black holes on the millimetre fundamental plane of black hole accretion

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2026) stag037

Authors:

Jacob S Elford, Ilaria Ruffa, Timothy A Davis, Martin Bureau, Rob Fender, Jindra Gensior, Thomas Williams, Hengyue Zhang

Abstract:

Abstract Recent work revealed the existence of a galaxy ‘millimetre fundamental plane of black hole accretion’, a tight correlation between nuclear 1 mm luminosity, intrinsic 2 – 10 keV X-ray luminosity and supermassive black hole mass, originally discovered for nearby low- and high-luminosity active galactic nuclei. Here we use mm and X-ray data of 5 X-ray binaries (XRBs) to demonstrate that these stellar-mass black holes also lie on the mm fundamental plane, as they do at radio wavelengths. One source for which we have multi-epoch observations shows evidence of deviations from the plane after a state change, suggesting that the plane only applies to XRBs in the hard state, as is true again at radio wavelengths. We show that both advection-dominated accretion flows and compact jet models predict the existence of the plane across the entire range of black hole masses, although these models vary in their ability to accurately predict the XRB black hole masses.