12(month)

The PHANGS-JWST Treasury Survey: Star Formation, Feedback, and Dust Physics at High Angular resolution in Nearby GalaxieS

First author: Janice C. Lee The PHANGS collaboration has been building a reference dataset for the multi-scale, multi-phase study of star formation and the interstellar medium in nearby galaxies. With the successful launch and commissioning of JWST, we can now obtain high-resolution infrared imaging to probe the youngest stellar populations and dust emission on the scales of star clusters and molecular clouds ($\sim$5-50 pc). In Cycle 1, PHANGS is conducting an 8-band imaging survey from 2-21$\mu$m of 19 nearby spiral galaxies.

The prevalence and influence of circumstellar material around hydrogen-rich supernova progenitors

First author: Rachel J. Bruch Spectroscopic detection of transient narrow emission lines (flash-ionisation features) traces the presence of circumstellar material (CSM) around massive stars exploding as core-collapse supernovae. Transient emission lines disappearing shortly after the SN explosion suggest that the spatial extent of this material is compact; hence implying that the progenitor star experienced episodes of enhanced mass loss shortly prior to explosion. The early light curves of Type II supernovae (SNe II) are assumed to be initially powered by shock-cooling emission.

The structure and composition of multiphase galactic winds in a Large Magellanic Cloud mass simulated galaxy

First author: Ulrich P. Steinwandel We present the first results from a high resolution simulation with a focus on galactic wind driving for an isolated galaxy with a halo mass of $\sim 10^{11}$ M${\odot}$ (similar to the Large Magellanic Cloud) and a total gas mass of $\sim 6 \times 10^{8}$ M${\odot}$, resulting in $\sim 10^{8}$ gas cells at $\sim 4$ M${\odot}$ mass resolution. We adopt a resolved stellar feedback model with non-equilibrium cooling and heating, including photoelectric heating and photo-ionizing radiation, as well as supernovae (SNe), coupled to the second order meshless finite mass (MFM) method for hydrodynamics.

The Type Ibn Supernova 2019kbj -- Indications for Diversity in Type Ibn Supernova Progenitors

First author: Tom Ben-Ami Type Ibn supernovae (SNe) are a rare class of stellar explosions whose progenitor systems are not yet well determined. We present and analyze observations of the Type Ibn SN 2019kbj, and model its light curve in order to constrain its progenitor and explosion parameters. SN 2019kbj shows roughly constant temperature during the first month after peak, indicating a power source (likely CSM interaction) that keeps the continuum emission hot at ~15000K.

THESAN-HR: How does reionization impact early galaxy evolution?

First author: Josh Borrow Early galaxies were the radiation source for reionization, with the photoheating feedback from the reionization process expected to reduce the efficiency of star formation in low mass haloes. Hence, to fully understand reionization and galaxy formation, we must study their impact on each other. The THESAN project has so far aimed to study the impact of galaxy formation physics on reionization, but here we present the new THESAN simulations with a factor 50 higher resolution ($m_{\rm b} \approx 10^4$~M$\odot$) that aim to self-consistently study the back-reaction of reionization on galaxies.

Three dimensional magnetorotational core-collapse supernova explosions of a 39 solar mass progenitor star

First author: Jade Powell We perform three-dimensional simulations of magnetorotational supernovae using a $39,M_{\odot}$ progenitor star with two different initial magnetic field strengths of $10^{10}$ G and $10^{12}$ G in the core. Both models rapidly undergo shock revival and their explosion energies asymptote within a few hundred milliseconds to values of $\gtrsim 2\times10^{51}$ erg after conservatively correcting for the binding energy of the envelope. Magnetically collimated, non-relativistic jets form in both models, though the jets are subject to non-axisymmetric instabilities.

Ultraviolet imaging observations of three jellyfish galaxies: Star formation suppression in the centre and ongoing star formation in stripped tails

First author: Koshy George Spiral galaxies undergo strong ram-pressure effects when they fall into the galaxy cluster potential. As a consequence, their gas is stripped to form extended tails within which star formation can happen, giving them the typical jellyfish appearance. The ultraviolet imaging observations of jellyfish galaxies provide an opportunity to understand ongoing star formation in the stripped tails. We report the ultraviolet observations of the jellyfish galaxies JW39, JO60, JO194 and compare with observations in optical continuum and $\mathrm{H}{\alpha}$.

Understanding globular cluster abundances through nuclear reactions

P Adsley Globular clusters contain multiple stellar populations, with some previous generation of stars polluting the current stars with heavier elements. Understanding the history of globular clusters is helpful in understanding how galaxies merged and evolved and therefore constraining the site or sites of this historic pollution is a priority. The acceptable temperature and density conditions of these polluting sites depend on critical <span class="search-hit mathjax">reaction</span> rates. In this paper, three experimental studies helping to constrain astrophysically important <span class="search-hit mathjax">reaction</span> rates are briefly discussed.

What it takes to solve the Hubble tension through modifications of cosmological recombination

First author: Nanoom Lee We develop a novel general formalism allowing us to obtain values of the Hubble constant in agreement with late-time observables without degrading the fit to Cosmic Microwave Background data, considering perturbative modifications around a fiducial $\Lambda$CDM cosmology. Taking as proof-of-principle the case of a time-varying electron mass and fine structure constant, we demonstrate that a modified recombination can solve the Hubble tension and lower $S_8$ to match weak lensing measurements.