A test of linearity of the ratio of dark matter to baryonic matter in galaxy clusters

First author: Varenya Upadhyaya We search for a linearity in the ratio of dark matter to baryonic matter as a function of radius for galaxy clusters, motivated by a recent result by Lovas (arXiv:2206.11431), who has discovered such a linearity for a diverse suite of galaxies in the SPARC sample. For our analysis, we used a sample of 54 non-cool core clusters from the HIFLUGCS sample. We do not find any evidence for a linear trend in the aforementioned ratio as a function of radius for individual clusters.

A theoretical study of the time-lags due to Comptonization and the constraints on the X-ray corona in AGN

First author: W. Zhang We study the Fourier time-lags due to the Comptonization of disc-emitted photons in a spherical, uniform, and stationary X-ray corona, which located on the rotational axis of the black hole. We use Monk, a general relativistic Monte-Carlo radiative transfer code, to calculate Compton scattering of photons emitted by a thin disc with a Novikov-Thorne temperature profile. We find that the model time-lags due to Comptonization remain constant up to a characteristic frequency and then rapidly decrease to zero at higher frequencies.

Addressing Cosmological Tensions by Non-Local Gravity

First author: Filippo Bouchè Alternative cosmological models have been under deep scrutiny in recent years, aiming to address the main shortcomings of the $\Lambda$CDM model. Moreover, as the accuracy of cosmological surveys improved, new tensions have risen between the model-dependent analysis of the Cosmic Microwave Background and lower redshift probes. Within this framework, we review two quantum-inspired non-locally extended theories of gravity, whose main cosmological feature is a geometrically driven accelerated expansion.

AGN Feedback in SDSS-IV MaNGA: AGNs Have Suppressed Central Star-Formation Rates

First author: Caleb Lammers Despite the importance of feedback from active galactic nuclei (AGN) in models of galaxy evolution, observational constraints on the influence of AGN feedback on star formation remain weak. To this end, we have compared the star formation trends of 279 low-redshift AGN galaxies with 558 non-active control galaxies using integral field unit spectroscopy from the SDSS-IV MaNGA survey. With a Gaussian process-based methodology, we reconstruct non-parametric star formation histories in spatially-resolved spaxels covering the face of each galaxy.

AGN Feedback Through Multiple Jet Cycles in the Seyfert Galaxy NGC 2639

First author: Vaishnav V. Rao The Seyfert galaxy NGC 2639 is known to exhibit three episodes of AGN jet/lobe activity. We present here the upgraded Giant Metrewave Radio Telescope (uGMRT) 735 MHz image of NGC 2639 showing a fourth episode as witnessed by the discovery of $\sim9$ kpc radio lobes misaligned with the previously known $\sim1.5$ kpc, $\sim360$ parsec, and $\sim3$ parsec jet features detected through the Karl G. Jansky Very Large Array (VLA) and the Very Long Baseline Array (VLBA), respectively.

AGN quenching in simulated dwarf galaxies

Roark Habegger In galactic disks, the Parker instability results when non-thermal pressure support exceeds a certain threshold. The non-thermal pressures considered in the Parker instability are cosmic ray pressure and magnetic pressure. This instability takes a long time to saturate $(>500 , \mathrm{Myr})$ and assumes a background with fixed cosmic ray pressure to gas pressure ratio. In reality, galactic cosmic rays are injected into localized regions $(< 100 ,\mathrm{pc})$ by events like supernovae, increasing the cosmic ray pressure to gas pressure ratio.

AGN quenching in simulated dwarf galaxies

Ray S. Sharma We examine the quenching characteristics of $328$ isolated dwarf galaxies $\left(10^{8} < M_{\rm star}/M_\odot < 10^{10} \right)$ within the \Rom{} cosmological hydrodynamic simulation. Using mock observation methods, we identify isolated dwarf galaxies with quenched star formation and make direct comparisons to the quenched fraction in the NASA Sloan Atlas (NSA). Similar to other cosmological simulations, we find a population of quenched, isolated dwarf galaxies below $M_{\rm star} < 10^{9} M_\odot$ not detected within the NSA.

Angular Momentum Transfer in PQEs from Galaxy Nuclei

First author: Andrew King A suggested model for quasi–periodic eruptions (QPEs) from galaxy nuclei invokes a white dwarf in an eccentric orbit about the central massive black hole. I point out that the extreme mass ratio allows the presence of strong Lindblad resonances in the accretion disc. These are important for the stability of mass transfer, and may trigger the eruptions themselves by rapidly transferring angular momentum from the accretion disc (which is likely to be eccentric itself) to the orbiting WD companion at pericentre.

ASTROPHYSICAL S(0)-FACTORS FOR THE $^{3}{ m He}(α, γ)^{7}{ m Be}$, $^{3}{ m H}(α, γ)^{7}{ m Li}$ and $^{7}{ m Be}(p, γ)^{8}{ m B}$ DIRECT CAPTURE PROCESSES IN A POTENTIAL MODEL

S. A. Turakulov Astrophysical S-factors at zero energy for the direct <span class="search-hit mathjax">nuclear</span> capture <span class="search-hit mathjax">reactions</span> $^{3}{\rm He}(α, γ)^{7}{\rm Be}$, $^{3}{\rm H}(α, γ)^{7}{\rm Li}$ and $^{7}{\rm Be}(p, γ)^{8}{\rm B}$ are estimated within the framework of two-body potential cluster model on the basis of extranuclear capture approximation of D. Baye and E. Brainis. The values of S(0)-factors have been calculated using two different potential models for each process, which were adjusted to the binding energies and empirical values of the asymptotical normalization coefficients from the literature.

BIFROST: simulating compact subsystems in star clusters using a hierarchical fourth-order forward symplectic integrator code

Antti Rantala We present BIFROST, an extended version of the GPU-accelerated hierarchical fourth-order forward symplectic integrator code FROST. BIFROST (BInaries in FROST) can efficiently evolve collisional stellar systems with arbitrary binary fractions up to fbin=100% by using secular and regularised integration for binaries, triples, multiple systems or small clusters around black holes within the fourth-order forward integrator framework. Post-Newtonian (PN) terms up to order PN3.5 are included in the equations of motion of compact subsystems with optional three-body and spin-dependent terms.