Running Late: Exploring the Delayed Supermassive Black Hole Growth Seen by Hydro-Dynamical Simulations

Despite the vast amount of processes that depend on the co-evolution of supermassive black holes (SMBHs) and their host galaxies, their physical relationship is still not fully understood. Observations have revealed a well-constrained scaling relation between SMBH mass and galaxy bulge mass in the local universe. In galaxy formation simulations, a different form of SMBH growth behavior emerges at high redshift: prolonged slow growth in the early universe followed by coherent fueling that results in a rapid increase in the central BH's mass. After this "catch-up" period of rapid growth, the SMBH growth resembles the well documented observed local scaling relation between SMBH mass and galaxy bulge mass. We conduct an in-depth study of these SMBH growth behaviors to explore implications it has on the early universe scaling relation. We construct a simple model, using said behaviors, to predict the quasar luminosity function which can be compared to well-documented observable quantities. To combine the simulation behaviors with a mock catalog of galaxies, we employ mathematical convolution techniques. This involves numerical integration methods over a population of dark matter halos and various models that relate the dark matter halo population to quasar luminosity. The models this study produces to resemble the simulation behaviors contains three free parameters. Thus, we employ a least squares fit method on a three dimensional parameter space to find the free parameters that best fit the predictions of our study to various observational data. These results allow us to systematically quantify the range of allowed scenarios for the emergence of the scaling relation between SMBH mass and galaxy bulge mass observed in the local universe

Yellowstone Harvest Festival, Livingston, Montana

attendees of the Yellowstone Harvest Festival. Surveys were implemented on site during the event. A total of 78 event attendees participated in the survey. Results show that 81% of respondents were residents of Montana and of those Montana residents, 33% were from Park County. Out-of-county respondents spent an average of 3.55 nights away from home. Of those nights, an average of 2.46 of those nights were in Livingston and 3.50 nights in other nearby locations. Respondents to the survey reported a total spending of $18,134 in the Livingston/Park County area. Results provide event organizers and Explore Livingston with useful data for future event planning, making improvements to the event, event marketing/promotion, and understanding the visitor spending associated with the event

Selectivity of Facial Aftereffects for Changes in Gender and Expression

The ability to perceive and distinguish faces is a fundamental role of the visual system, though how the visual system accomplishes this goal remains poorly understood. A common method used to explore the neural mechanisms underlying face perception is to examine face adaptation aftereffects. For instance, when an observer views a distorted face (e.g. contracted) for a prolonged period of time, a normal face will appear to be distorted in the opposite direction (e.g. expanded). Several studies have utilized these adaptation aftereffects in order to investigate how adaptation transfers across different types of faces, to test whether common or separate neural pathways code different facial attributes. Two attributes that are thought to be processed by largely separate neural subsystems are the expression and identity of the face. In the present study, we examined the selectivity of face aftereffects for differences in gender or expression, in order to further elucidate how expression and identity are encoded in the brain. We tested the prediction that adaptation should show stronger transfer across changes in facial expression because expression changes do not alter the perceived identity of faces. The results of this study showed weak selectivity for changes in expression or gender, as well as modest differences between these two forms of natural facial variation. The results thus were inconsistent with the proposal that variant features of the face, like an expression change, will have less influence on adaptation than an invariant change, like gender or identity. Instead, the results suggest that changes in expression or gender have comparable effects, and may be represented in similar ways at least with regard to the mechanisms mediating face adaptation

The Event at Rebecca Farm 2023, Kalispell, Montana

This study was conducted for Rebecca Farm to provide insight into the characteristics of attendees to the twentysecond annual The Event at Rebecca Farm. Paper surveys were completed by 158 attendees of the event. Results show that 41% of attendees were residents of Flathead Country and 59% came from outside of Flathead County. Visitors spent an average of 6.55 nights in the Flathead Valley area. People spent the most money (96,336) on accommodations (hotel/motel/B&B/rental cabin/home), followed by restaurants/bars (21,265), then the Rebecca Farm Trade Fair ($17,126). Respondents to the survey reported total spending of$199,471 in the Flathead Valley. Results provide event organizers at Rebecca Farm and the Kalispell Chamber of Commerce/CVB with useful data for future event planning, making improvements to the event, event marketing/promotion, and understanding visitor spending associated with the event

Montana Folk Festival 2023, Butte, Montana

This study was conducted for the non-profit Mainstreet Uptown Butte to provide insight into the characteristics of attendees of the 2023 Montana Folk Festival. Paper surveys were completed by 860 attendees of the event. Results show that 82% of respondents were residents of Montana, and of those Montana residents, 45% were from Butte-Silver Bow County. Out-of-county respondents spent an average of 3.43 nights in Butte-Silver Bow County and more people spent money on restaurants/bars and hotel/motel while visiting the area than any other spending categories. Respondents to the survey reported a total spending of $199,074.00 in the Butte-Silver Bow County area. Results provide event organizers and Mainstreet Uptown Butte with useful data for future event planning, making improvements to the event, event marketing/promotion, and understanding the visitor spending associated with the event

Efficient Long-range Active Galactic Nuclei (AGNs) Feedback Affects the Low-redshift Lyα Forest

Active galactic nuclei (AGNs) feedback models are generally calibrated to reproduce galaxy observables such as the stellar mass function and the bimodality in galaxy colors. We use variations of the AGN feedback implementations in the IllustrisTNG (TNG) and Simba cosmological hydrodynamic simulations to show that the low-redshift Lyα forest can provide constraints on the impact of AGN feedback. We show that TNG overpredicts the number density of absorbers at column densities N HI < 1014 cm−2 compared to data from the Cosmic Origins Spectrograph (in agreement with previous work), and we demonstrate explicitly that its kinetic feedback mode, which is primarily responsible for galaxy quenching, has a negligible impact on the column density distribution (CDD) of absorbers. In contrast, we show that the fiducial Simba model, which includes AGN jet feedback, is the preferred fit to the observed CDD of the z = 0.1 Lyα forest across 5 orders of magnitude in column density. We show that the Simba results with jets produce a quantitatively better fit to the observational data than the Simba results without jets, even when the ultraviolet background is left as a free parameter. AGN jets in Simba are high speed, collimated, weakly interacting with the interstellar medium (via brief hydrodynamic decoupling), and heated to the halo virial temperature. Collectively these properties result in stronger long-range impacts on the intergalactic medium when compared to TNG’s kinetic feedback mode, which drives isotropic winds with lower velocities at the galactic radius. Our results suggest that the low-redshift Lyα forest provides plausible evidence for long-range AGN jet feedback

Efficient long-range active galactic nuclei (agns) feedback affects the low-redshift lyα forest

Active galactic nuclei (AGNs) feedback models are generally calibrated to reproduce galaxy observables such as the stellar mass function and the bimodality in galaxy colors. We use variations of the AGN feedback implementations in the IllustrisTNG (TNG) and SIMBA cosmological hydrodynamic simulations to show that the low-redshift Lyα forest can provide constraints on the impact of AGN feedback. We show that TNG overpredicts the number density of absorbers at column densities NHI < 1014 cm−2 compared to data from the Cosmic Origins Spectrograph (in agreement with previous work), and we demonstrate explicitly that its kinetic feedback mode, which is primarily responsible for galaxy quenching, has a negligible impact on the column density distribution (CDD) of absorbers. In contrast, we show that the fiducial SIMBA model, which includes AGN jet feedback, is the preferred fit to the observed CDD of the z = 0.1 Lyα forest across 5 orders of magnitude in column density. We show that the SIMBA results with jets produce a quantitatively better fit to the observational data than the SIMBA results without jets, even when the ultraviolet background is left as a free parameter

2013-2014 Clemson LGBTQ Task Force Recommendations

In December of 2011, a group of faculty, staff, students, alumni, and other Clemson community members came together to discuss the invisibility of the queer and trans communities in the “Clemson family” message. The event was held at the Madren Center and sponsored in part by the then‐Dean of Students Joy Smith. One of the motivating factors of the meeting was Clemson University’s unfortunately low score, 2 out of 5 stars, on the National LGBT‐Friendly Campus Climate Assessment tool from Campus Pride. The average score among the Top‐20 Public Schools (U.S. News & World Report, 2013) is 4.4 out of 5 stars. Of the Top‐25 Public Schools, only Clemson scored below a 3 out of 5 stars. Our main motivation stemmed from the controversial off‐campus beating of a gay Clemson student. Leading up to the confrontation gay slurs were used against two students and one student suffered a physical attack. From the meeting’s exhaustive list of findings, three items were identified as priorities: establishment of a LGBTQ commission, establishment of a LGBTQ resource center, and same‐sex spousal benefits. Of the three, the establishment of a commission was pursued by Leon Wiles (Chief Diversity Officer), Susan Hilligoss (English faculty), and Joshua Morgan (library staff). Bylaws were drafted, and in November of 2012, a smaller representative group appeared before President Jim Barker to present their rationale for the establishment of a commission. The president responded by appointing a task force to act in an advisory capacity and to continue the discussion about how to make members of the queer and trans communities feel welcome and safe in the Clemson family

The low redshift Lyman-α\alpha Forest as a constraint for models of AGN feedback

We study the low redshift Lyman-$\alpha$ Forest in the Illustris and IllustrisTNG (TNG) cosmological simulations to demonstrate their utility in constraining aspects of sub-grid models of feedback from active galactic nuclei (AGN). The two simulations share an identical Ultraviolet Background prescription and similar cosmological parameters, but TNG features an entirely reworked AGN feedback model. Therefore a comparison of these simulations is useful to assess the effects of an altered AGN sub-grid model on the low redshift Lyman-$\alpha$ Forest. We find significant differences in the IGM temperature-density relation between the two simulations due to changes in the gas heating rate due to AGN. We investigate Lyman-$\alpha$ Forest observables such as the column density distribution function, flux PDF, and Doppler width ($b$-parameter) distribution. Due to the AGN radio mode model, the original Illustris simulations have a factor of 2-3 fewer absorbers than TNG at column densities $N_{\rm HI}< 10^{15.5}$ cm$^{-2}$. We show that TNG is in much better agreement with the observed $z=0.1$ flux power spectrum than Illustris. The differences in the amplitude and shape of the flux PDF and power spectrum between Illustris and TNG cannot be attributed to simple changes in the photoheating rate. We also compare the simulated Forest statistics to UV data from the Cosmic Origins Spectrograph (COS) and find that neither simulation can reproduce the slope of the absorber distribution. Both Illustris and TNG also produce significantly smaller $b$-parameter distributions than observed in the COS data, possibly due to unresolved or missing sources of turbulence.Comment: Submitted to ApJL, comments welcom

An Exploration of AGN and Stellar Feedback Effects in the Intergalactic Medium via the Low Redshift Lyman-α\alpha Forest

We explore the role of galactic feedback on the low redshift Lyman-$\alpha$ (Ly$\alpha$)~forest ($z \lesssim 2$) statistics and its potential to alter the thermal state of the intergalactic medium. Using the Cosmology and Astrophysics with Machine Learning Simulations (CAMELS) suite, we explore variations of the AGN and stellar feedback models in the IllustrisTNG and Simba sub-grid models. We find that both AGN and stellar feedback in Simba play a role in setting the Ly$\alpha$ forest column density distribution function (CDD) and the Doppler width ($b$-value) distribution. The Simba AGN jet feedback mode is able to efficiently transport energy out to the diffuse IGM causing changes in the shape and normalization of the CDD and a broadening of the $b$-value distribution. We find that stellar feedback plays a prominent role in regulating supermassive black hole growth and feedback, highlighting the importance of constraining stellar and AGN feedback simultaneously. In IllustrisTNG, the AGN feedback variations explored in CAMELS do not affect the Ly$\alpha$ forest, but varying the stellar feedback model does produce subtle changes. Our results imply that the low-$z$ Ly$\alpha$ forest can be sensitive to changes in the ultraviolet background (UVB), stellar and black hole feedback, and that AGN jet feedback in particular can have a strong effect on the thermal state of the IGM.Comment: 26 pages, 11 figures, 2 tables, submitted to Ap