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Creators/Authors contains: "Telford, O Grace"

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  1. Abstract

    The interaction between supermassive black hole (SMBH) feedback and the circumgalactic medium (CGM) continues to be an open question in galaxy evolution. In our study, we use smoothed particle hydrodynamics simulations to explore the impact of SMBH feedback on galactic metal retention and the motion of metals and gas into and through the CGM of L*galaxies. We examine 140 galaxies from the 25 Mpc cosmological volume Romulus25, with stellar masses between log(M*/M) = 9.5–11.5. We measure the fraction of metals remaining in the interstellar medium (ISM) and CGM of each galaxy and calculate the expected mass of each SMBH based on theMBHσrelation (Kormendy & Ho 2013). The deviation of each SMBH from its expected mass, ΔMBH, is compared to the potential of its host viaσ. We find that SMBHs with accreted mass aboveMBHσare more effective at removing metals from the ISM than undermassive SMBHs in star-forming galaxies. Overall, overmassive SMBHs suppress the total star formation of their host galaxies and more effectively move metals from the ISM into the CGM. However, we see little to no evacuation of gas from the CGM out of their halos, in contrast with other simulations. Finally, we predict that Civcolumn densities in the CGM of L*galaxies are unlikely to depend on host galaxy SMBH mass. Our results show that the scatter in the low-mass end of the MBHσrelation may indicate how effective an SMBH is in the local redistribution of mass in its host galaxy.

     
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    Free, publicly-accessible full text available May 22, 2025
  2. The interaction between supermassive black hole (SMBH) feedback and the circumgalactic medium (CGM) continues to be an open question in galaxy evolution. In our study, we use SPH simulations to explore the impact of SMBH feedback on galactic metal retention and the motion of metals and gas into and through the CGM of L ∗ galaxies. We examine 140 galaxies from the 25 Mpc cosmological volume, Romulus25, with stellar masses between 3 × 10 9 - 3 × 10 11 M ⊙ . We measure the fraction of metals remaining in the ISM and CGM of each galaxy, and calculate the expected mass of its SMBH based on the M−σ relation. The deviation of each SMBH from its expected mass, ΔMBH is compared to the potential of its host via σ . We find that SMBHs with accreted mass above the empirical M−σ relation are about 15\% more effective at removing metals from the ISM than under-massive SMBHs in star forming galaxies. Over-massive SMBHs suppress the overall star formation of their host galaxies and more effectively move metals from the ISM into the CGM. However, we see little evidence for the evacuation of gas from their halos, in contrast with other simulations. Finally, we predict that C IV column densities in the CGM of L ∗ galaxies may depend on host galaxy SMBH mass. Our results show that the scatter in the low mass end of M−σ relation may indicate how effective a SMBH is at the local redistribution of mass in its host galaxy. 
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  3. Abstract

    We measure the spatially resolved recent star formation history (SFH) of M33 using optical images taken with the Hubble Space Telescope as part of the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) survey. The area covered by the observations used in this analysis covers a de-projected area of ∼38 kpc2and extends to ∼3.5 and ∼2 kpc from the center of M33 along the major and semimajor axes, respectively. We divide the PHATTER optical survey into 2005 regions that measure 24 arcsec, ∼100 pc, on a side and fit color–magnitude diagrams for each region individually to measure the spatially resolved SFH of M33 within the PHATTER footprint. There are significant fluctuations in the SFH on small spatial scales and also galaxy-wide scales that we measure back to about 630 Myr ago. We observe a more flocculent spiral structure in stellar populations younger than about 80 Myr, while the structure of the older stellar populations is dominated by two spiral arms. We also observe a bar in the center of M33, which dominates at ages older than about 80 Myr. Finally, we find that the mean star formation rate (SFR) over the last 100 Myr within the PHATTER footprint is 0.32 ± 0.02 Myr−1. We measure a current SFR (over the last 10 Myr) of 0.20 ± 0.03 Myr−1. This SFR is slightly higher than previous measurements from broadband estimates, when scaled to account for the fraction of the D25 area covered by the PHATTER survey footprint.

     
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