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We present an analysis of the first two XRISM/Resolve spectra of the well-known Seyfert-1.5 active galactic nucleus (AGN) in NGC 4151, obtained in 2023 December. Our work focuses on the nature of the narrow Fe K _α emission line at 6.4 keV, the strongest and most common X-ray line observed in AGN. The total line is found to consist of three components. Even the narrowest component of the line is resolved with evident Fe K _α _,1 (6.404 keV) and K _α _,2 (6.391 keV) contributions in a 2:1 flux ratio, fully consistent with neutral gas with negligible bulk velocity. Subject to the limitations of our models, the narrowest and intermediate-width components are consistent with emission from optically thin gas, suggesting that they arise in a disk atmosphere and/or wind. Modeling the three line components in terms of Keplerian broadening, they are readily associated with (1) the inner wall of the “torus,” (2) the innermost optical “broad-line region” (or “X-ray BLR”), and (3) a region with a radius of r ≃ 100 GM / c ^2 that may signal a warp in the accretion disk. Viable alternative explanations of the broadest component include a fast-wind component and/or scattering; however, we find evidence of variability in the narrow Fe K _α line complex on timescales consistent with small radii. The best-fit models are statistically superior to simple Voigt functions, but when fit with Voigt profiles the time-averaged lines are consistent with a projected velocity broadening of FWHM $\,=\,{1600}_{-200}^{+400}\,\mathrm{km}\,{{\rm{s}}}^{-1}$ . Overall, the resolution and sensitivity of XRISM show that the narrow Fe K line in AGN is an effective probe of all key parts of the accretion flow, as it is currently understood. We discuss the implications of these findings for our understanding of AGN accretion, future studies with XRISM, and X-ray-based black hole mass measurements.

We report 13 years of Chandra monitoring of the youngest Galactic supernova remnant G1.9+0.3, the only remnant known to be increasing in brightness. We confirm the spatially integrated rate of flux increase of (1.2 ± 0.2)% yr ^−1 (1–7 keV), but find large spatial variations, from −3% yr ^−1 to +7% yr ^−1 , over length scales as small as 10″ or smaller. We observe relatively little change in spectral slope, though one region shows significant hardening as it brightens by 1% yr ^−1 . Such rates of change can be accommodated by any of several explanations, including steady blast-wave evolution, expansion or compression of discrete plasma blobs, magnetic turbulence, or variations in magnetic-field aspect angle. Our results do not constrain the mean magnetic-field strength, but a self-consistent picture can be produced in which the maximum particle energies are limited by the remnant age (applying both to electrons and to ions) to about 20 TeV, and the remnant-averaged magnetic-field strength is about 30 μ G. The deceleration parameter m (average shock radius varying as t ^m ) is about 0.7, consistent with estimates from overall expansion dynamics and confirming an explosion date of about 1900 CE. Shock-efficiency factors ϵ _e and ϵ _B (fractions of shock energy in relativistic electrons and magnetic field) are 0.003 and 0.0002 in this picture. However, the large range of rates of brightness change indicates that such a global model is oversimplified. Temporal variations of photon index, expected to be small but measurable with longer time baselines, can discriminate among possible models.

Ambulatory management of congestive heart failure (HF) continues to be a challenging clinical problem. Recent studies have focused on the role of HF clinics, nurse practitioners and disease management programmes to reduce HF readmissions. This pilot study is a pragmatic factorial study comparing a coach intervention, a SMARTPHONE REMINDER system intervention and BOTH interventions combined to Treatment as USUAL (TAU). We determined that both modalities were acceptable to patients prior to randomisation. Fifty-four patients were randomised to the four groups. The COACH group had no readmissions for HF 6 months after enrolment compared with 18% for the SMARTPHONE REMINDER Group, 8% for the BOTH intervention group and 13% for TAU. Medium-to-high medication adherence was maintained in all four groups although sodium consumption was lower at 3 months for the COACH and combined (BOTH) groups. This pilot study suggests a beneficial effect on rehospitalisation with the use of support measures including coaches and telephone reminders that needs confirmation in a larger trial.