185,566 results on '"Buckley, A."'
Search Results
2. From Pre-College Grads to Undergrads: Encouraging Full-Time Enrollment after Summer Programs
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Meghan Buckley
- Abstract
This guest perspective argues that converting in-person summer pre-college program participants into matriculated, degree-seeking undergraduate students at that same institution is a multi-step process that involves: 1) strategic pre-college program recruitment, 2) a curated and well-rounded summer pre-college experience that is both academically rigorous and socially dynamic, and 3) continued and consistent post-program engagement. It also argues that summer pre-college programs should work intentionally with Admissions departments during pre- and post-program development to create the most effective recruiting and enrollment pipelines from pre-college to eventual matriculation.
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- 2024
3. A Broadband X-ray Investigation of Fast-Spinning Intermediate Polar CTCV J2056-3014
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Salcedo, Cro, Mori, Kaya, Bridges, Gabriel, Hailey, Charles J., Buckley, David A. H., de Oliveira, Raimundo Lopes, Ramsay, Gavin, and van Dyk, Anke
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We report on XMM-Newton, NuSTAR, and NICER X-ray observations of CTCV J2056-3014, a cataclysmic variable (CV) with one of the fastest-spinning white dwarfs (WDs) at P = 29.6 s. While previously classified as an intermediate polar (IP), CJ2056 also exhibits the properties of WZ-Sge-type CVs, such as dwarf novae and superoutbursts. With XMM-Newton and NICER, we detected the spin period up to approximately 2 keV with 7-$\sigma$ significance. We constrained its derivative to |$\dot{P}$| < 1.8e-12 s/s after correcting for binary orbital motion. The pulsed profile is characterized by a single broad peak with approximately 25% modulation. NuSTAR detected a four-fold increase in unabsorbed X-ray flux coincident with an optical flare in November 2022. The XMM-Newton and NICER X-ray spectra in 0.3-10 keV are best characterized by an absorbed optically-thin three-temperature thermal plasma model (kT = 0.3, 1.0, and 4.9 keV), while the NuSTAR spectra in 3-30 keV are best fit by a single-temperature thermal plasma model (kT = 8.4 keV), both with Fe abundance $Z_{Fe}/Z_\odot$ = 0.3. CJ2056 exhibits similarities to other fast-spinning CVs, such as low plasma temperatures, and no significant X-ray absorption at low energies. As the WD's magnetic field strength is unknown, we applied both non-magnetic and magnetic CV spectral models (MKCFLOW and MCVSPEC) to determine the WD mass. The derived WD mass range (M = 0.7-1.0 $M_\odot$) is above the centrifugal break-up mass limit of 0.56 $M_\odot$ and consistent with the mean WD mass of local CVs (M $\approx$ 0.8-0.9 $M_\odot$)., Comment: 22 pages, 12 figures, accepted to ApJ
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- 2024
4. Millinovae: a new class of transient supersoft X-ray sources
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Mróz, Przemek, Król, Krzysztof, Szegedi, Hélène, Charles, Philip, Page, Kim L., Udalski, Andrzej, Buckley, David A. H., Dewangan, Gulab, Meintjes, Pieter, Szymański, Michał K., Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Poleski, Radosław, Skowron, Jan, Ulaczyk, Krzysztof, Gromadzki, Mariusz, Rybicki, Krzysztof, Iwanek, Patryk, Wrona, Marcin, and Mróz, Mateusz J.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Some accreting binary systems containing a white dwarf (such as classical novae or persistent supersoft sources) are seen to emit low energy X-rays with temperatures of ~10^6 K and luminosities exceeding 10^35 erg/s. These X-rays are thought to originate from nuclear burning on the white dwarf surface, either caused by a thermonuclear runaway (classical novae) or a high mass accretion rate that sustains steady nuclear burning (persistent sources). The discovery of transient supersoft X-rays from ASASSN-16oh challenged these ideas, as no signatures of nuclear fusion were detected, and the origin of these X-rays remains controversial. It was unclear whether this star was one of a kind or representative of a larger, as yet undiscovered, group. Here we present the discovery of 29 stars located in the direction of the Magellanic Clouds exhibiting long-duration, symmetrical optical outbursts similar to that seen in ASASSN-16oh. We observed one of these objects during an optical outburst and found it to be emitting transient supersoft X-rays, while no signatures of mass ejection (indicative of a classical nova eruption) were detected. We therefore propose that these objects form a homogeneous group of transient supersoft X-ray sources, which we dub `millinovae' because their optical luminosities are approximately a thousand times fainter than those of ordinary classical novae., Comment: submitted to AAS Journals
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- 2024
5. Visualizing Dynamics of Charges and Strings in (2+1)D Lattice Gauge Theories
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Cochran, Tyler A., Jobst, Bernhard, Rosenberg, Eliott, Lensky, Yuri D., Gyawali, Gaurav, Eassa, Norhan, Will, Melissa, Abanin, Dmitry, Acharya, Rajeev, Beni, Laleh Aghababaie, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Ballard, Brian, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Bourassa, Alexandre, Bovaird, Jenna, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Ben, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Das, Sayan, Demura, Sean, De Lorenzo, Laura, Di Paolo, Agustin, Donohoe, Paul, Drozdov, Ilya, Dunsworth, Andrew, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Gasca, Robert, Genois, Élie, Giang, William, Gilboa, Dar, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Gross, Jonathan A., Habegger, Steve, Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heu, Paula, Higgott, Oscar, Hilton, Jeremy, Huang, Hsin-Yuan, Huff, Ashley, Huggins, William J., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Karamlou, Amir H., Kechedzhi, Kostyantyn, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kim, Seon, Klimov, Paul V., Kobrin, Bryce, Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Kurilovich, Vladislav D., Landhuis, David, Lange-Dei, Tiano, Langley, Brandon W., Lau, Kim-Ming, Ledford, Justin, Lee, Kenny, Lester, Brian J., Guevel, Loïck Le, Li, Wing Yan, Lill, Alexander T., Livingston, William P., Locharla, Aditya, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Maloney, Ashley, Mandrà, Salvatore, Martin, Leigh S., Martin, Orion, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Megrant, Anthony, Miao, Kevin C., Molavi, Reza, Molina, Sebastian, Montazeri, Shirin, Movassagh, Ramis, Neill, Charles, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, Niu, Murphy Yuezhen, Oliver, William D., Ottosson, Kristoffer, Pizzuto, Alex, Potter, Rebecca, Pritchard, Orion, Quintana, Chris, Ramachandran, Ganesh, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Small, Spencer, Smith, W. Clarke, Springer, Sofia, Sterling, George, Suchard, Jordan, Szasz, Aaron, Sztein, Alex, Thor, Douglas, Torunbalci, M. Mert, Vaishnav, Abeer, Vargas, Justin, Vdovichev, Sergey, Vidal, Guifre, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., Ware, Brayden, White, Theodore, Wong, Kristi, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Zobris, Nicholas, Boixo, Sergio, Kelly, Julian, Lucero, Erik, Chen, Yu, Smelyanskiy, Vadim, Neven, Hartmut, Gammon-Smith, Adam, Pollmann, Frank, Knap, Michael, and Roushan, Pedram
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Quantum Physics ,Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Lattice - Abstract
Lattice gauge theories (LGTs) can be employed to understand a wide range of phenomena, from elementary particle scattering in high-energy physics to effective descriptions of many-body interactions in materials. Studying dynamical properties of emergent phases can be challenging as it requires solving many-body problems that are generally beyond perturbative limits. We investigate the dynamics of local excitations in a $\mathbb{Z}_2$ LGT using a two-dimensional lattice of superconducting qubits. We first construct a simple variational circuit which prepares low-energy states that have a large overlap with the ground state; then we create particles with local gates and simulate their quantum dynamics via a discretized time evolution. As the effective magnetic field is increased, our measurements show signatures of transitioning from deconfined to confined dynamics. For confined excitations, the magnetic field induces a tension in the string connecting them. Our method allows us to experimentally image string dynamics in a (2+1)D LGT from which we uncover two distinct regimes inside the confining phase: for weak confinement the string fluctuates strongly in the transverse direction, while for strong confinement transverse fluctuations are effectively frozen. In addition, we demonstrate a resonance condition at which dynamical string breaking is facilitated. Our LGT implementation on a quantum processor presents a novel set of techniques for investigating emergent particle and string dynamics.
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- 2024
6. R-AIF: Solving Sparse-Reward Robotic Tasks from Pixels with Active Inference and World Models
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Nguyen, Viet Dung, Yang, Zhizhuo, Buckley, Christopher L., and Ororbia, Alexander
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Computer Science - Robotics ,Computer Science - Artificial Intelligence ,Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Machine Learning ,68T40 (Primary) 68T07, 68T37, 68T05 (Secondary) ,I.2.9 ,I.2.10 ,G.3 ,I.2.6 - Abstract
Although research has produced promising results demonstrating the utility of active inference (AIF) in Markov decision processes (MDPs), there is relatively less work that builds AIF models in the context of environments and problems that take the form of partially observable Markov decision processes (POMDPs). In POMDP scenarios, the agent must infer the unobserved environmental state from raw sensory observations, e.g., pixels in an image. Additionally, less work exists in examining the most difficult form of POMDP-centered control: continuous action space POMDPs under sparse reward signals. In this work, we address issues facing the AIF modeling paradigm by introducing novel prior preference learning techniques and self-revision schedules to help the agent excel in sparse-reward, continuous action, goal-based robotic control POMDP environments. Empirically, we show that our agents offer improved performance over state-of-the-art models in terms of cumulative rewards, relative stability, and success rate. The code in support of this work can be found at https://github.com/NACLab/robust-active-inference., Comment: 20 pages, 2 algorithms, 2 tables, 5 figures, submitted to ICRA 2025
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- 2024
7. Emergent Collective Reproduction via Evolving Neuronal Flocks
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Le, Nam H., Watson, Richard, Levin, Mike, and Buckley, Chrys
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Quantitative Biology - Populations and Evolution ,Computer Science - Artificial Intelligence ,Computer Science - Neural and Evolutionary Computing - Abstract
This study facilitates the understanding of evolutionary transitions in individuality (ETIs) through a novel artificial life framework, named VitaNova, that intricately merges self-organization and natural selection to simulate the emergence of complex, reproductive groups. By dynamically modelling individual agents within an environment that challenges them with predators and spatial constraints, VitaNova elucidates the mechanisms by which simple agents evolve into cohesive units exhibiting collective reproduction. The findings underscore the synergy between self-organized behaviours and adaptive evolutionary strategies as fundamental drivers of ETIs. This approach not only contributes to a deeper understanding of higher-order biological individuality but also sets a new precedent in the empirical investigation of ETIs, challenging and extending current theoretical frameworks., Comment: 9 pages, 10 figures, conference
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- 2024
8. First Resolution of Microlensed Images of a Binary-Lens Event
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Wu, Zexuan, Dong, Subo, Mérand, A., Kochanek, Christopher S., Mróz, Przemek, Shangguan, Jinyi, Christie, Grant, Tan, Thiam-Guan, Bensby, Thomas, Bland-Hawthorn, Joss, Buder, Sven, Eisenhauer, Frank, Gould, Andrew P., Kos, Janez, Natusch, Tim, Sharma, Sanjib, Udalski, Andrzej, Woillez, J., Buckley, David A. H., Thompson, I. B., Dayem, Karim Abd El, Alecian, Evelyne, Babusiaux, Carine, Berdeu, Anthony, Berger, Jean-Philippe, Bourdarot, Guillaume, Brandner, Wolfgang, Clavel, Maica, Davies, Richard I., Defrère, Denis, Dougados, Catherine, Drescher, Antonia, Eckart, Andreas, Fabricius, Maximilian, Feuchtgruber, Helmut, Schreiber, Natascha M. Förster, Garcia, Paulo, Genzel, Reinhard, Gillessen, Stefan, Heißel, Gernot, Hönig, Sebastian, Houlle, Mathis, Kervella, Pierre, Kreidberg, Laura, Lacour, Sylvestre, Lai, Olivier, Laugier, Romain, Bouquin, Jean-Baptiste Le, Leftley, James, Lopez, Bruno, Lutz, Dieter, Mang, Felix, Millour, Florentin, Montargès, Miguel, Nowacki, Hugo, Nowak, Mathias, Ott, Thomas, Paumard, Thibaut, Perraut, Karine, Perrin, Guy, Petrov, Romain, Petrucci, Pierre-Olivier, Pourre, Nicolas, Rabien, Sebastian, Ribeiro, Diogo C., Robbe-Dubois, Sylvie, Bordoni, Matteo Sadun, Santos, Daryl, Sauter, Jonas, Scigliuto, Jules, Shimizu, Taro T., Straubmeier, Christian, Sturm, Eckhard, Subroweit, Matthias, Sykes, Calvin, Tacconi, Linda, Vincent, Frédéric, and Widmann, Felix
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We resolve the multiple images of the binary-lens microlensing event ASASSN-22av using the GRAVITY instrument of the Very Large Telescope Interferometer (VLTI). The light curves show weak binary perturbations, complicating the analysis, but the joint modeling with the VLTI data breaks several degeneracies, arriving at a strongly favored solution. Thanks to precise measurements of angular Einstein radius \theta_E = 0.726 +/- 0.002 mas and microlens parallax, we determine that the lens system consists of two M dwarfs with masses of M_1 = 0.261 +/- 0.009 M_sun and M_2 = 0.252 +/- 0.017 M_sun, a projected separation of r_\perp = 7.42 +/- 0.33 AU and a distance of D_L = 2.31 +/- 0.09 kpc. The successful VLTI observations of ASASSN-22av open up a new path for studying intermediate-separation (i.e., a few AUs) stellar-mass binaries, including those containing dark compact objects such as neutron stars and stellar-mass black holes., Comment: see the ancillary file for animation associated with Fig. 8
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- 2024
9. Short-term variability of the transitional pulsar candidate CXOU J110926.4-650224 from X-rays to infrared
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Zelati, F. Coti, de Martino, D., Dhillon, V. S., Marsh, T. R., Vincentelli, F., Campana, S., Torres, D. F., Papitto, A., Baglio, M. C., Zanon, A. Miraval, Rea, N., Brink, J., Buckley, D. A. H., D'Avanzo, P., Illiano, G., Manca, A., and Marino, A.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
CXOU J110926.4-650224 is a candidate transitional millisecond pulsar (tMSP) with X-ray and radio emission properties reminiscent of those observed in confirmed tMSPs in their X-ray 'subluminous' disc state. We present the results of observing campaigns that, for the first time, characterise the optical and near-infrared variability of this source and establish a connection with the mode-switching phenomenon observed in X-rays. The optical emission exhibited flickering activity, frequent dipping episodes where it appeared redder, and a multi-peaked flare where it was bluer. The variability pattern was strongly correlated with that of the X-ray emission. Each dip matched an X-ray low-mode episode, indicating that a significant portion of the optical emission originates from nearly the same region as the X-ray emission. The near-infrared emission also displayed remarkable variability, including a dip of 20 min in length during which it nearly vanished. Time-resolved optical spectroscopic observations reveal significant changes in the properties of emission lines from the disc and help infer the spectral type of the companion star to be between K0 and K5. We compare the properties of CXOU J110926.4-650224 with those of other tMSPs in the X-ray subluminous disc state and discuss our findings within the context of a recently proposed scenario that explains the phenomenology exhibited by the prototypical tMSP PSR J1023+0038., Comment: 12 pages, 7 figures, 2 tables. Accepted for publication on Astronomy & Astrophysics
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- 2024
10. Exploring Action-Centric Representations Through the Lens of Rate-Distortion Theory
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Varona, Miguel de Llanza, Buckley, Christopher L., and Millidge, Beren
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Computer Science - Artificial Intelligence ,Quantitative Biology - Neurons and Cognition - Abstract
Organisms have to keep track of the information in the environment that is relevant for adaptive behaviour. Transmitting information in an economical and efficient way becomes crucial for limited-resourced agents living in high-dimensional environments. The efficient coding hypothesis claims that organisms seek to maximize the information about the sensory input in an efficient manner. Under Bayesian inference, this means that the role of the brain is to efficiently allocate resources in order to make predictions about the hidden states that cause sensory data. However, neither of those frameworks accounts for how that information is exploited downstream, leaving aside the action-oriented role of the perceptual system. Rate-distortion theory, which defines optimal lossy compression under constraints, has gained attention as a formal framework to explore goal-oriented efficient coding. In this work, we explore action-centric representations in the context of rate-distortion theory. We also provide a mathematical definition of abstractions and we argue that, as a summary of the relevant details, they can be used to fix the content of action-centric representations. We model action-centric representations using VAEs and we find that such representations i) are efficient lossy compressions of the data; ii) capture the task-dependent invariances necessary to achieve successful behaviour; and iii) are not in service of reconstructing the data. Thus, we conclude that full reconstruction of the data is rarely needed to achieve optimal behaviour, consistent with a teleological approach to perception.
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- 2024
11. Learning in Hybrid Active Inference Models
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Collis, Poppy, Singh, Ryan, Kinghorn, Paul F, and Buckley, Christopher L
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Computer Science - Artificial Intelligence ,Electrical Engineering and Systems Science - Systems and Control - Abstract
An open problem in artificial intelligence is how systems can flexibly learn discrete abstractions that are useful for solving inherently continuous problems. Previous work in computational neuroscience has considered this functional integration of discrete and continuous variables during decision-making under the formalism of active inference (Parr, Friston & de Vries, 2017; Parr & Friston, 2018). However, their focus is on the expressive physical implementation of categorical decisions and the hierarchical mixed generative model is assumed to be known. As a consequence, it is unclear how this framework might be extended to learning. We therefore present a novel hierarchical hybrid active inference agent in which a high-level discrete active inference planner sits above a low-level continuous active inference controller. We make use of recent work in recurrent switching linear dynamical systems (rSLDS) which implement end-to-end learning of meaningful discrete representations via the piecewise linear decomposition of complex continuous dynamics (Linderman et al., 2016). The representations learned by the rSLDS inform the structure of the hybrid decision-making agent and allow us to (1) specify temporally-abstracted sub-goals in a method reminiscent of the options framework, (2) lift the exploration into discrete space allowing us to exploit information-theoretic exploration bonuses and (3) `cache' the approximate solutions to low-level problems in the discrete planner. We apply our model to the sparse Continuous Mountain Car task, demonstrating fast system identification via enhanced exploration and successful planning through the delineation of abstract sub-goals., Comment: 11 pages (+ appendix). Accepted to the International Workshop on Active Inference 2024. arXiv admin note: substantial text overlap with arXiv:2408.10970
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- 2024
12. Gradient-free variational learning with conditional mixture networks
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Heins, Conor, Wu, Hao, Markovic, Dimitrije, Tschantz, Alexander, Beck, Jeff, and Buckley, Christopher
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence ,Statistics - Machine Learning - Abstract
Balancing computational efficiency with robust predictive performance is crucial in supervised learning, especially for critical applications. Standard deep learning models, while accurate and scalable, often lack probabilistic features like calibrated predictions and uncertainty quantification. Bayesian methods address these issues but can be computationally expensive as model and data complexity increase. Previous work shows that fast variational methods can reduce the compute requirements of Bayesian methods by eliminating the need for gradient computation or sampling, but are often limited to simple models. We demonstrate that conditional mixture networks (CMNs), a probabilistic variant of the mixture-of-experts (MoE) model, are suitable for fast, gradient-free inference and can solve complex classification tasks. CMNs employ linear experts and a softmax gating network. By exploiting conditional conjugacy and P\'olya-Gamma augmentation, we furnish Gaussian likelihoods for the weights of both the linear experts and the gating network. This enables efficient variational updates using coordinate ascent variational inference (CAVI), avoiding traditional gradient-based optimization. We validate this approach by training two-layer CMNs on standard benchmarks from the UCI repository. Our method, CAVI-CMN, achieves competitive and often superior predictive accuracy compared to maximum likelihood estimation (MLE) with backpropagation, while maintaining competitive runtime and full posterior distributions over all model parameters. Moreover, as input size or the number of experts increases, computation time scales competitively with MLE and other gradient-based solutions like black-box variational inference (BBVI), making CAVI-CMN a promising tool for deep, fast, and gradient-free Bayesian networks., Comment: 16 pages main text (3 figures), including references. 9 pages supplementary material (5 figures)
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- 2024
13. Axion Dark Matter eXperiment around 3.3 {\mu}eV with Dine-Fischler-Srednicki-Zhitnitsky Discovery Ability
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Bartram, C., Boutan, C., Braine, T., Buckley, J. H., Caligiure, T. J., Carosi, G., Chou, A. S., Cisneros, C., Clarke, John, Daw, E. J., Du, N., Duffy, L. D., Dyson, T. A., Gaikwad, C., Gleason, J. R., Goodman, C., Goryachev, M., Guzzetti, M., Hanretty, C., Hartman, E., Hipp, A. T., Hoffman, J., Hollister, M., Khatiwada, R., Knirck, S., Kuo, C. L., Lentz, E., McAllister, B. T., Mostyn, C., Murch, K., Oblath, N. S., Perry, M. G., Quiskamp, A., Robertson, N., Rosenberg, L. J, Ruppert, S., Rybka, G., Siddiqi, I., Sikivie, P., Sinnis, J., Solano, M. E., Sonnenschein, A., Sullivan, N. S., Tanner, D. B., Taubman, M. S., Tobar, M. E., Withers, M. O., Woollett, N., and Zhang, D.
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High Energy Physics - Experiment - Abstract
We report the results of a QCD axion dark matter search with discovery ability for Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) axions using an axion haloscope. Sub-Kelvin noise temperatures are reached with an ultra low-noise Josephson parametric amplifier cooled by a dilution refrigerator. This work excludes (with a 90% confidence level) DFSZ axions with masses between 3.27 to 3.34 {\mu}eV, assuming a standard halo model with a local energy density of 0.45 GeV/cc made up 100% of axions.
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- 2024
14. Quantum error correction below the surface code threshold
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Acharya, Rajeev, Aghababaie-Beni, Laleh, Aleiner, Igor, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Astrakhantsev, Nikita, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Ballard, Brian, Bardin, Joseph C., Bausch, Johannes, Bengtsson, Andreas, Bilmes, Alexander, Blackwell, Sam, Boixo, Sergio, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Yu, Chen, Zijun, Chiaro, Ben, Chik, Desmond, Chou, Charina, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Das, Sayan, Davies, Alex, De Lorenzo, Laura, Debroy, Dripto M., Demura, Sean, Devoret, Michel, Di Paolo, Agustin, Donohoe, Paul, Drozdov, Ilya, Dunsworth, Andrew, Earle, Clint, Edlich, Thomas, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Garcia, Gonzalo, Gasca, Robert, Genois, Élie, Giang, William, Gidney, Craig, Gilboa, Dar, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Gross, Jonathan A., Habegger, Steve, Hall, John, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heras, Francisco J. H., Heslin, Stephen, Heu, Paula, Higgott, Oscar, Hill, Gordon, Hilton, Jeremy, Holland, George, Hong, Sabrina, Huang, Hsin-Yuan, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Jordan, Stephen, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Karamlou, Amir H., Kechedzhi, Kostyantyn, Kelly, Julian, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kim, Seon, Klimov, Paul V., Klots, Andrey R., Kobrin, Bryce, Kohli, Pushmeet, Korotkov, Alexander N., Kostritsa, Fedor, Kothari, Robin, Kozlovskii, Borislav, Kreikebaum, John Mark, Kurilovich, Vladislav D., Lacroix, Nathan, Landhuis, David, Lange-Dei, Tiano, Langley, Brandon W., Laptev, Pavel, Lau, Kim-Ming, Guevel, Loïck Le, Ledford, Justin, Lee, Kenny, Lensky, Yuri D., Leon, Shannon, Lester, Brian J., Li, Wing Yan, Li, Yin, Lill, Alexander T., Liu, Wayne, Livingston, William P., Locharla, Aditya, Lucero, Erik, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Malone, Fionn D., Maloney, Ashley, Mandrá, Salvatore, Martin, Leigh S., Martin, Steven, Martin, Orion, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Megrant, Anthony, Mi, Xiao, Miao, Kevin C., Mieszala, Amanda, Molavi, Reza, Molina, Sebastian, Montazeri, Shirin, Morvan, Alexis, Movassagh, Ramis, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Nersisyan, Ani, Neven, Hartmut, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, O'Brien, Thomas E., Oliver, William D., Opremcak, Alex, Ottosson, Kristoffer, Petukhov, Andre, Pizzuto, Alex, Platt, John, Potter, Rebecca, Pritchard, Orion, Pryadko, Leonid P., Quintana, Chris, Ramachandran, Ganesh, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Rosenberg, Eliott, Rosenfeld, Emma, Roushan, Pedram, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Senior, Andrew W., Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Singh, Shraddha, Sivak, Volodymyr, Skruzny, Jindra, Small, Spencer, Smelyanskiy, Vadim, Smith, W. Clarke, Somma, Rolando D., Springer, Sofia, Sterling, George, Strain, Doug, Suchard, Jordan, Szasz, Aaron, Sztein, Alex, Thor, Douglas, Torres, Alfredo, Torunbalci, M. Mert, Vaishnav, Abeer, Vargas, Justin, Vdovichev, Sergey, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., Ware, Brayden, Weber, Kate, White, Theodore, Wong, Kristi, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, and Zobrist, Nicholas
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Quantum Physics - Abstract
Quantum error correction provides a path to reach practical quantum computing by combining multiple physical qubits into a logical qubit, where the logical error rate is suppressed exponentially as more qubits are added. However, this exponential suppression only occurs if the physical error rate is below a critical threshold. In this work, we present two surface code memories operating below this threshold: a distance-7 code and a distance-5 code integrated with a real-time decoder. The logical error rate of our larger quantum memory is suppressed by a factor of $\Lambda$ = 2.14 $\pm$ 0.02 when increasing the code distance by two, culminating in a 101-qubit distance-7 code with 0.143% $\pm$ 0.003% error per cycle of error correction. This logical memory is also beyond break-even, exceeding its best physical qubit's lifetime by a factor of 2.4 $\pm$ 0.3. We maintain below-threshold performance when decoding in real time, achieving an average decoder latency of 63 $\mu$s at distance-5 up to a million cycles, with a cycle time of 1.1 $\mu$s. To probe the limits of our error-correction performance, we run repetition codes up to distance-29 and find that logical performance is limited by rare correlated error events occurring approximately once every hour, or 3 $\times$ 10$^9$ cycles. Our results present device performance that, if scaled, could realize the operational requirements of large scale fault-tolerant quantum algorithms., Comment: 10 pages, 4 figures, Supplementary Information
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- 2024
15. Massive stars exploding in a He-rich circumstellar medium $-$ X. Flash spectral features in the Type Ibn SN 2019cj and observations of SN 2018jmt
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Wang, Z. -Y., Pastorello, A., Maeda, K., Reguitti, A., Cai, Y. -Z., Howell, D. Andrew, Benetti, S., Buckley, D., Cappellaro, E., Carini, R., Cartier, R., Chen, T. -W., Elias-Rosa, N., Fang, Q. -L., Gal-Yam, A., Gangopadhyay, A., Gromadzki, M., Gan, W. -P., Hiramatsu, D., Hu, M. -K., Inserra, C., McCully, C., Nicholl, M., Olivares, F. E., Pignata, G., Pineda-Garc'ia, J., Pursiainen, M., Ragosta, F., Rau, A., Roy, R., Sollerman, J., Tartaglia, L., Terreran, G., Valerin, G., Wang, Q., Wang, S. -Q., Young, D. R., Aryan, A., Bronikowski, M., Concepcion, E., Galbany, L., Lin, H., Melandri, A., Petrushevska, T., Ramirez, M., Shi, D. -D, Warwick, B., Zhang, J. -J., Wang, B., Wang, X. -F., and Zhu, X. -J.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We present optical and near-infrared observations of two Type Ibn supernovae (SNe), SN 2018jmt and SN 2019cj. Their light curves have rise times of about 10 days, reaching an absolute peak magnitude of $M_g$(SN 2018jmt) = $-$19.07 $\pm$ 0.37 and $M_V$(SN 2019cj) = $-$18.94 $\pm$ 0.19 mag, respectively. The early-time spectra of SN 2018jmt are dominated by a blue continuum, accompanied by narrow (600$-$1000 km~s$^{-1}$) He I lines with P-Cygni profile. At later epochs, the spectra become more similar to those of the prototypical SN Ibn 2006jc. At early phases, the spectra of SN 2019cj show flash ionisation emission lines of C III, N III and He II superposed on a blue continuum. These features disappear after a few days, and then the spectra of SN 2019cj evolve similarly to those of SN 2018jmt. The spectra indicate that the two SNe exploded within a He-rich circumstellar medium (CSM) lost by the progenitors a short time before the explosion. We model the light curves of the two SNe Ibn to constrain the progenitor and the explosion parameters. The ejecta masses are consistent with either that expected for a canonical SN Ib ($\sim$ 2 M$_{\odot}$) or those from a massive WR star ($>$ $\sim$ 4 M$_{\odot}$), with the kinetic energy on the order of $10^{51}$ erg. The lower limit on the ejecta mass ($>$ $\sim$ 2 M$_{\odot}$) argues against a scenario involving a relatively low-mass progenitor (e.g., $M_{ZAMS}$ $\sim$ 10 M$_{\odot}$). We set a conservative upper limit of $\sim$0.1 M$_{\odot}$ for the $^{56}$Ni masses in both SNe. From the light curve modelling, we determine a two-zone CSM distribution, with an inner, flat CSM component, and an outer CSM with a steeper density profile. The physical properties of SN 2018jmt and SN 2019cj are consistent with those expected from the core collapse of relatively massive, stripped-envelope (SE) stars., Comment: 28 pages, 19 figures, Accepted for publication in Astronomy & Astrophysics
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- 2024
16. Only Strict Saddles in the Energy Landscape of Predictive Coding Networks?
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Innocenti, Francesco, Achour, El Mehdi, Singh, Ryan, and Buckley, Christopher L.
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence ,Computer Science - Neural and Evolutionary Computing ,Statistics - Machine Learning ,I.2.6 - Abstract
Predictive coding (PC) is an energy-based learning algorithm that performs iterative inference over network activities before weight updates. Recent work suggests that PC can converge in fewer learning steps than backpropagation thanks to its inference procedure. However, these advantages are not always observed, and the impact of PC inference on learning is theoretically not well understood. Here, we study the geometry of the PC energy landscape at the (inference) equilibrium of the network activities. For deep linear networks, we first show that the equilibrated energy is simply a rescaled mean squared error loss with a weight-dependent rescaling. We then prove that many highly degenerate (non-strict) saddles of the loss including the origin become much easier to escape (strict) in the equilibrated energy. Our theory is validated by experiments on both linear and non-linear networks. Based on these results, we conjecture that all the saddles of the equilibrated energy are strict. Overall, this work suggests that PC inference makes the loss landscape more benign and robust to vanishing gradients, while also highlighting the challenge of speeding up PC inference on large-scale models., Comment: 26 pages, 12 figures
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- 2024
17. Hybrid Recurrent Models Support Emergent Descriptions for Hierarchical Planning and Control
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Collis, Poppy, Singh, Ryan, Kinghorn, Paul F, and Buckley, Christopher L
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Computer Science - Artificial Intelligence ,Electrical Engineering and Systems Science - Systems and Control - Abstract
An open problem in artificial intelligence is how systems can flexibly learn discrete abstractions that are useful for solving inherently continuous problems. Previous work has demonstrated that a class of hybrid state-space model known as recurrent switching linear dynamical systems (rSLDS) discover meaningful behavioural units via the piecewise linear decomposition of complex continuous dynamics (Linderman et al., 2016). Furthermore, they model how the underlying continuous states drive these discrete mode switches. We propose that the rich representations formed by an rSLDS can provide useful abstractions for planning and control. We present a novel hierarchical model-based algorithm inspired by Active Inference in which a discrete MDP sits above a low-level linear-quadratic controller. The recurrent transition dynamics learned by the rSLDS allow us to (1) specify temporally-abstracted sub-goals in a method reminiscent of the options framework, (2) lift the exploration into discrete space allowing us to exploit information-theoretic exploration bonuses and (3) `cache' the approximate solutions to low-level problems in the discrete planner. We successfully apply our model to the sparse Continuous Mountain Car task, demonstrating fast system identification via enhanced exploration and non-trivial planning through the delineation of abstract sub-goals., Comment: 4 pages, 3 figures
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- 2024
18. Imagen 3
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Imagen-Team-Google, Baldridge, Jason, Bauer, Jakob, Bhutani, Mukul, Brichtova, Nicole, Bunner, Andrew, Chan, Kelvin, Chen, Yichang, Dieleman, Sander, Du, Yuqing, Eaton-Rosen, Zach, Fei, Hongliang, de Freitas, Nando, Gao, Yilin, Gladchenko, Evgeny, Colmenarejo, Sergio Gómez, Guo, Mandy, Haig, Alex, Hawkins, Will, Hu, Hexiang, Huang, Huilian, Igwe, Tobenna Peter, Kaplanis, Christos, Khodadadeh, Siavash, Kim, Yelin, Konyushkova, Ksenia, Langner, Karol, Lau, Eric, Luo, Shixin, Mokrá, Soňa, Nandwani, Henna, Onoe, Yasumasa, Oord, Aäron van den, Parekh, Zarana, Pont-Tuset, Jordi, Qi, Hang, Qian, Rui, Ramachandran, Deepak, Rane, Poorva, Rashwan, Abdullah, Razavi, Ali, Riachi, Robert, Srinivasan, Hansa, Srinivasan, Srivatsan, Strudel, Robin, Uria, Benigno, Wang, Oliver, Wang, Su, Waters, Austin, Wolff, Chris, Wright, Auriel, Xiao, Zhisheng, Xiong, Hao, Xu, Keyang, van Zee, Marc, Zhang, Junlin, Zhang, Katie, Zhou, Wenlei, Zolna, Konrad, Aboubakar, Ola, Akbulut, Canfer, Akerlund, Oscar, Albuquerque, Isabela, Anderson, Nina, Andreetto, Marco, Aroyo, Lora, Bariach, Ben, Barker, David, Ben, Sherry, Berman, Dana, Biles, Courtney, Blok, Irina, Botadra, Pankil, Brennan, Jenny, Brown, Karla, Buckley, John, Bunel, Rudy, Bursztein, Elie, Butterfield, Christina, Caine, Ben, Carpenter, Viral, Casagrande, Norman, Chang, Ming-Wei, Chang, Solomon, Chaudhuri, Shamik, Chen, Tony, Choi, John, Churbanau, Dmitry, Clement, Nathan, Cohen, Matan, Cole, Forrester, Dektiarev, Mikhail, Du, Vincent, Dutta, Praneet, Eccles, Tom, Elue, Ndidi, Feden, Ashley, Fruchter, Shlomi, Garcia, Frankie, Garg, Roopal, Ge, Weina, Ghazy, Ahmed, Gipson, Bryant, Goodman, Andrew, Górny, Dawid, Gowal, Sven, Gupta, Khyatti, Halpern, Yoni, Han, Yena, Hao, Susan, Hayes, Jamie, Hertz, Amir, Hirst, Ed, Hou, Tingbo, Howard, Heidi, Ibrahim, Mohamed, Ike-Njoku, Dirichi, Iljazi, Joana, Ionescu, Vlad, Isaac, William, Jana, Reena, Jennings, Gemma, Jenson, Donovon, Jia, Xuhui, Jones, Kerry, Ju, Xiaoen, Kajic, Ivana, Ayan, Burcu Karagol, Kelly, Jacob, Kothawade, Suraj, Kouridi, Christina, Ktena, Ira, Kumakaw, Jolanda, Kurniawan, Dana, Lagun, Dmitry, Lavitas, Lily, Lee, Jason, Li, Tao, Liang, Marco, Li-Calis, Maggie, Liu, Yuchi, Alberca, Javier Lopez, Lu, Peggy, Lum, Kristian, Ma, Yukun, Malik, Chase, Mellor, John, Mosseri, Inbar, Murray, Tom, Nematzadeh, Aida, Nicholas, Paul, Oliveira, João Gabriel, Ortiz-Jimenez, Guillermo, Paganini, Michela, Paine, Tom Le, Paiss, Roni, Parrish, Alicia, Peckham, Anne, Peswani, Vikas, Petrovski, Igor, Pfaff, Tobias, Pirozhenko, Alex, Poplin, Ryan, Prabhu, Utsav, Qi, Yuan, Rahtz, Matthew, Rashtchian, Cyrus, Rastogi, Charvi, Raul, Amit, Rebuffi, Sylvestre-Alvise, Ricco, Susanna, Riedel, Felix, Robinson, Dirk, Rohatgi, Pankaj, Rosgen, Bill, Rumbley, Sarah, Ryu, Moonkyung, Salgado, Anthony, Singla, Sahil, Schroff, Florian, Schumann, Candice, Shah, Tanmay, Shillingford, Brendan, Shivakumar, Kaushik, Shtatnov, Dennis, Singer, Zach, Sluzhaev, Evgeny, Sokolov, Valerii, Sottiaux, Thibault, Stimberg, Florian, Stone, Brad, Stutz, David, Su, Yu-Chuan, Tabellion, Eric, Tang, Shuai, Tao, David, Thomas, Kurt, Thornton, Gregory, Toor, Andeep, Udrescu, Cristian, Upadhyay, Aayush, Vasconcelos, Cristina, Vasiloff, Alex, Voynov, Andrey, Walker, Amanda, Wang, Luyu, Wang, Miaosen, Wang, Simon, Wang, Stanley, Wang, Qifei, Wang, Yuxiao, Weisz, Ágoston, Wiles, Olivia, Wu, Chenxia, Xu, Xingyu Federico, Xue, Andrew, Yang, Jianbo, Yu, Luo, Yurtoglu, Mete, Zand, Ali, Zhang, Han, Zhang, Jiageng, Zhao, Catherine, Zhaxybay, Adilet, Zhou, Miao, Zhu, Shengqi, Zhu, Zhenkai, Bloxwich, Dawn, Bordbar, Mahyar, Cobo, Luis C., Collins, Eli, Dai, Shengyang, Doshi, Tulsee, Dragan, Anca, Eck, Douglas, Hassabis, Demis, Hsiao, Sissie, Hume, Tom, Kavukcuoglu, Koray, King, Helen, Krawczyk, Jack, Li, Yeqing, Meier-Hellstern, Kathy, Orban, Andras, Pinsky, Yury, Subramanya, Amar, Vinyals, Oriol, Yu, Ting, and Zwols, Yori
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Computer Science - Computer Vision and Pattern Recognition - Abstract
We introduce Imagen 3, a latent diffusion model that generates high quality images from text prompts. We describe our quality and responsibility evaluations. Imagen 3 is preferred over other state-of-the-art (SOTA) models at the time of evaluation. In addition, we discuss issues around safety and representation, as well as methods we used to minimize the potential harm of our models.
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- 2024
19. CSS161010: a luminous, fast blue optical transient with broad blueshifted hydrogen lines
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Gutiérrez, Claudia P., Mattila, Seppo, Lundqvist, Peter, Dessart, Luc, González-Gaitán, Santiago, Jonker, Peter G., Dong, Subo, Coppejans, Deanne, Chen, Ping, Charalampopoulos, Panos, Elias-Rosa, Nancy, Reynolds, Thomas, Kochanek, Christopher, Fraser, Morgan, Pastorello, Andrea, Gromadzki, Mariusz, Neustadt, Jack, Benetti, Stefano, Kankare, Erkki, Kangas, Tuomas, Kotak, Rubina, Stritzinger, Maximilian D., Wevers, Thomas, Zhang, Bing, Bersier, David, Bose, Subhash, Buckley, David A. H., Dastidar, Raya, Gangopadhyay, Anjasha, Hamanowicz, Aleksandra, Kollmeier, Juna, Mao, Jirong, Potter, Stephen B., Romero-Colmenero, Encarni, Singh, Mridweeka, Somero, Auni, Terreran, Giacomo, Vaisanen, Petri, and Wyrzykowski, Lukasz
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present ultraviolet, optical and near-infrared photometric and optical spectroscopic observations of the luminous, fast blue optical transient (LFBOT), CSS161010:045834-081803 (CSS161010). The transient was found in a low-redshift (z=0.033) dwarf galaxy. The light curves of CSS161010 are characterized by an extremely fast evolution and blue colours. The V-band light curve shows that CSS161010 reaches an absolute peak of M$_{V}^{max}=-20.66\pm0.06$ mag in 3.8 days from the start of the outburst. After maximum, CSS161010 follows a power-law decline $\propto t^{-2.8\pm0.1}$ at all optical bands. These photometric properties are comparable to those of well-observed LFBOTs such as AT 2018cow, AT 2020mrf and AT 2020xnd. However, unlike these objects, the spectra of CSS161010 show a remarkable transformation from a blue and featureless continuum to spectra dominated by very broad, entirely blueshifted hydrogen emission lines of velocities of up to 10% of the speed of light. The persistent blueshifted emission and the lack of any emission at the rest wavelength of CSS161010 are unique features not seen in any transient before CSS161010. The combined observational properties of CSS161010 and its dwarf galaxy host favour the tidal disruption of a star by an intermediate-mass black hole as its origin., Comment: 29 pages (including the appendix); 8 figures in the main text, 4 figures and 8 tables in the appendix. Submitted to ApJ
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- 2024
20. V407 Lup, an intermediate polar nova
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Orio, M., Melicherčík, M., Ciroi, S., Canton, V., Aydi, E., Buckley, D. A. H., Dobrotka, A., Luna, G. J. M., and Ness, J.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We present X-ray and optical observations of nova V407 Lup (Nova Lup 2016), previously well monitored in outburst, as it returned to quiescent accretion. The X-ray light curve in 2020 February revealed a clear flux modulation with a stable period of 564.64$\pm$0.64 s, corresponding to the period measured in outburst and attributed to the spin of a magnetized white dwarf in an intermediate polar (IP) system. This detection in quiescence is consistent with the IP classification proposed after the nova eruption. The XMM-Newton EPIC X-ray flux is about 1.3 $\times 10^{-12}$ erg/cm$^2$/s at a distance, most likely, larger than 5 kpc, emitted in the whole 0.2-12 keV range without a significant cut-off energy. The X-ray spectra are complex; they can be fitted including a power law component with a relatively flat slope (a power law index of about 1), although, alternatively, a hard thermal component at kT$\geq$19 keV also yields a good fit. The SALT optical spectra obtained in 2019 March and 2022 May are quite typical of IPs, with strong emission lines, including some due to a high ionization potential, like He II at 4685.7 Angstrom. Nebular lines of O [III] were prominent in 2019 March, but their intensity and equivalent width appeared to be decreasing during that month, and they were no longer detectable in 2022, indicating that the nova ejecta dispersed. Complex profiles of the He II lines of V407 Lup are also characteristic of IPs, giving further evidence for this classification., Comment: Accepted for publication in MNRAS
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- 2024
21. CXOU J005245.0-722844: Discovery of a Be Star / White Dwarf binary system in the SMC via a very fast, super-Eddington X-ray outburst event
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Gaudin, Thomas M., Coe, Malcolm J., Kennea, Jamie A., Monageng, Itumaleng M., Buckley, David A. H., Udalski, Andrzej, and Evans, Phil A.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
CXOU J005245.0-722844 is an X-ray source in the Small Magellanic Cloud (SMC) that has long been known as a Be/X-ray binary (BeXRB) star, containing an OBe main sequence star and a compact object. In this paper, we report on a new very fast X-ray outburst from CXOU J005245.0-722844. X-ray observations taken by Swift constrain the duration of the outburst to less than 16 days and find that the source reached super-Eddington X-ray luminosities during the initial phases of the eruption. The XRT spectrum of CXOU J005245.0-722844 during this outburst reveals a super-soft X-ray source, best fit by an absorbed thermal blackbody model. Optical and Ultraviolet follow-up observations from the Optical Gravitational Lensing Experiment (OGLE), Asteroid Terrestrial-impact Last Alert System (ATLAS), and Swift identify a brief ~0.5 magnitude optical burst coincident with the X-ray outburst that lasted for less than 7 days. Optical photometry additionally identifies the orbital period of the system to be 17.55 days and identifies a shortening of the period to 17.14 days in the years leading up to the outburst. Optical spectroscopy from the Southern African Large Telescope (SALT) confirms that the optical companion is an early-type OBe star. We conclude from our observations that the compact object in this system is a white dwarf (WD), making this the seventh candidate Be/WD X-ray binary. The X-ray outburst is found to be the result of a very-fast, ultra-luminous nova similar to the outburst of MAXI J0158-744.
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- 2024
22. Why Teachers Integrate YPAR in Their Teaching: Cultivating Youth Wellbeing, Student Voice, and Social Justice
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Mary Frances Buckley-Marudas, Rosalinda Godínez, Karmel Abutaleb, Gray Cooper, Margaret Rahill, Drew Retherford, Sarah Schwab, Taylor Zepp, and Adam Voight
- Abstract
In this article, the authors share what they learned from considering a collection of narrative reflections written by six high school educators, all co-authors, who have integrated youth participatory action research (YPAR) into their instructional practice. Taken together, the written reflections shed light on teachers' reasons not only for pursuing YPAR but also for persisting with YPAR in their particular school context. The authors found that all teachers shared a commitment to social justice, yet their individual purposes for engaging with YPAR varied. Drawing on the teachers' written reflections, the authors delve into teachers' motivations for integrating YPAR into their teaching practice in order to conceptualize teachers' reasons for facilitating YPAR in school.
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- 2024
23. Integrating natural and cultural approaches in heritage conservation: Introduction to a Practice Note
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Buckley, Kristal, Brown, Steve, Ishizawa, Maya, Mitchell, Nora, Brown, Jessica, Leitão, Leticia, and Franceschini, Nicole
- Abstract
During the first years of Covid, 2020–2023, a group of seven colleagues across three continents—working outside of institutional contexts—prepared a Practice Note on naturecultures. The Practice Note draws together the long-time work, experience, and thinking of the authors, all of whom work in the field of heritage conservation. It gives focus to the improved integration of nature and culture, and cultural heritage and natural heritage, in the work of caring for and safeguarding important places. By promoting awareness of diversity and mutual respect for multiple views and understandings, the Practice Note is concerned with working together, fostering dialogue, and creating long-lasting and equitable approaches to conservation. In this introduction, we outline the purpose, origins, and the making of the Practice Note.
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- 2024
24. Advancing Understanding of Chemical Exposures and Maternal-child Health Through the U.S. Environmental Influences on Child Health Outcomes (ECHO) Program: A Scoping Review.
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Barrett, Emily, Ames, Jennifer, Eick, Stephanie, Peterson, Alicia, Rivera-Núñez, Zorimar, Starling, Anne, and Buckley, Jessie
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Chemical exposures ,Children’s health ,ECHO ,Pregnancy ,Humans ,Child Health ,United States ,Female ,Pregnancy ,Environmental Exposure ,Child ,Prenatal Exposure Delayed Effects ,Environmental Pollutants ,Maternal Exposure ,Child ,Preschool ,Child Development ,Infant ,Maternal Health - Abstract
PURPOSE OF REVIEW: Environmental chemical exposures may disrupt child development, with long-lasting health impacts. To date, U.S. studies of early environmental exposures have been limited in size and diversity, hindering power and generalizability. With harmonized data from over 60,000 participants representing 69 pregnancy cohorts, the National Institutes of Healths Environmental influences on Child Health Outcomes (ECHO) Program is the largest study of U.S. childrens health. Here, we: (1) review ECHO-wide studies of chemical exposures and maternal-child health; and (2) outline opportunities for future research using ECHO data. RECENT FINDINGS: As of early 2024, in addition to over 200 single-cohort (or award) papers on chemical exposures supported by ECHO, ten collaborative multi-cohort papers have been made possible by ECHO data harmonization and new data collection. Multi-cohort papers have examined prenatal exposure to per- and polyfluoroalkyl substances (PFAS), phthalates, phenols and parabens, organophosphate esters (OPEs), metals, melamine and aromatic amines, and emerging contaminants. They have primarily focused on describing patterns of maternal exposure or examining associations with maternal and infant outcomes; fewer studies have examined later child outcomes (e.g., autism) although follow up of enrolled ECHO children continues. The NICHDs Data and Specimen Hub (DASH) database houses extensive ECHO data including over 470,000 chemical assay results and complementary data on priority outcome areas (pre, peri-, and postnatal, airway, obesity, neurodevelopment, and positive health), making it a rich resource for future analyses. ECHOs extensive data repository, including biomarkers of chemical exposures, can be used to advance our understanding of environmental influences on childrens health. Although few published studies have capitalized on these unique harmonized data to date, many analyses are underway with data now widely available.
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- 2024
25. The Impact of Social Deprivation on Anterior Urethral Stricture Recurrence After Urethroplasty - A Trauma and Urologic Reconstructive Network of Surgeons (TURNS) Analysis.
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Patel, Hiren V, Li, Kevin D, Rourke, Keith, Smith, Thomas G, Voelzke, Bryan B, Myers, Jeremy B, Broghammer, Joshua A, Alsikafi, Nejd F, Buckley, Jill C, Zhao, Lee C, Elliott, Sean P, Vanni, Alex J, Peterson, Andrew C, Erickson, Bradley A, and Breyer, Benjamin N
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Biomedical and Clinical Sciences ,Clinical Sciences ,Clinical Research ,Social Determinants of Health ,Behavioral and Social Science ,Urologic Diseases ,Good Health and Well Being ,l determinants of health ,neighborhood disadvantage ,recurrence ,socia ,urethral stricture ,urethroplasty - Abstract
Introduction and objectivesSeveral factors influence recurrence after urethral stricture repair. The impact of socioeconomic factors on stricture recurrence after urethroplasty is poorly understood. This study aims to assess the impact that social deprivation, an area-level measure of disadvantage, has on urethral stricture recurrence after urethroplasty.MethodsWe performed a retrospective review of patients undergoing urethral reconstruction by surgeons participating in a collaborative research group. Home zip code was used to calculate Social Deprivation Indices (SDI; 0-100), which quantifies the level of disadvantage across several sociodemographic domains collected in the American Community Survey. Patients without zip code data were excluded from the analysis. The Cox Proportional Hazards model was used to study the association between SDI and the hazard of functional recurrence, adjusting for stricture characteristics as well as age and body mass index.ResultsMedian age was 46.0 years with a median follow up of 367 days for the 1452 men included in the study. Patients in the fourth SDI quartile (worst social deprivation) were more likely to be active smokers with traumatic and infectious strictures compared to the first SDI quartile. Patients in the fourth SDI quartile had 1.64 times the unadjusted hazard of functional stricture recurrence vs patients in the first SDI quartile (95% CI 1.04-2.59). Compared to anastomotic ± excision, substitution only repair had 1.90 times the unadjusted hazard of recurrence. The adjusted hazard of recurrence was 1.08 per 10-point increase in SDI (95% CI 1.01-1.15, P = .027).ConclusionsPatient social deprivation identifies those at higher risk for functional recurrence after anterior urethral stricture repair, offering an opportunity for preoperative counseling and postoperative surveillance. Addressing these social determinants of health can potentially improve outcomes in reconstructive surgery.
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- 2024
26. The Early Data Release of the Dark Energy Spectroscopic Instrument
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Collaboration, DESI, Adame, AG, Aguilar, J, Ahlen, S, Alam, S, Aldering, G, Alexander, DM, Alfarsy, R, Prieto, C Allende, Alvarez, M, Alves, O, Anand, A, Andrade-Oliveira, F, Armengaud, E, Asorey, J, Avila, S, Aviles, A, Bailey, S, Balaguera-Antolínez, A, Ballester, O, Baltay, C, Bault, A, Bautista, J, Behera, J, Beltran, SF, BenZvi, S, Silva, L Beraldo E, Bermejo-Climent, JR, Berti, A, Besuner, R, Beutler, F, Bianchi, D, Blake, C, Blum, R, Bolton, AS, Brieden, S, Brodzeller, A, Brooks, D, Brown, Z, Buckley-Geer, E, Burtin, E, Cabayol-Garcia, L, Cai, Z, Canning, R, Cardiel-Sas, L, Rosell, A Carnero, Castander, FJ, Cervantes-Cota, JL, Chabanier, S, Chaussidon, E, Chaves-Montero, J, Chen, S, Chen, X, Chuang, C, Claybaugh, T, Cole, S, Cooper, AP, Cuceu, A, Davis, TM, Dawson, K, de Belsunce, R, de la Cruz, R, de la Macorra, A, Della Costa, J, de Mattia, A, Demina, R, Demirbozan, U, DeRose, J, Dey, A, Dey, B, Dhungana, G, Ding, J, Ding, Z, Doel, P, Doshi, R, Douglass, K, Edge, A, Eftekharzadeh, S, Eisenstein, DJ, Elliott, A, Ereza, J, Escoffier, S, Fagrelius, P, Fan, X, Fanning, K, Fawcett, VA, Ferraro, S, Flaugher, B, Font-Ribera, A, Forero-Romero, JE, Forero-Sánchez, D, Frenk, CS, Gänsicke, BT, García, LÁ, García-Bellido, J, Garcia-Quintero, C, Garrison, LH, Gil-Marín, H, Golden-Marx, J, and Gontcho, S Gontcho A
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Astronomical Sciences ,Physical Sciences ,Astronomical and Space Sciences ,Astronomy & Astrophysics ,Astronomical sciences ,Particle and high energy physics - Abstract
The Dark Energy Spectroscopic Instrument (DESI) completed its 5 month Survey Validation in 2021 May. Spectra of stellar and extragalactic targets from Survey Validation constitute the first major data sample from the DESI survey. This paper describes the public release of those spectra, the catalogs of derived properties, and the intermediate data products. In total, the public release includes good-quality spectral information from 466,447 objects targeted as part of the Milky Way Survey, 428,758 as part of the Bright Galaxy Survey, 227,318 as part of the Luminous Red Galaxy sample, 437,664 as part of the Emission Line Galaxy sample, and 76,079 as part of the Quasar sample. In addition, the release includes spectral information from 137,148 objects that expand the scope beyond the primary samples as part of a series of secondary programs. Here, we describe the spectral data, data quality, data products, Large-Scale Structure science catalogs, access to the data, and references that provide relevant background to using these spectra.
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- 2024
27. Review of Particle Physics*
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Navas, S, Amsler, C, Gutsche, T, Hanhart, C, Hernández-Rey, JJ, Lourenço, C, Masoni, A, Mikhasenko, M, Mitchell, RE, Patrignani, C, Schwanda, C, Spanier, S, Venanzoni, G, Yuan, CZ, Agashe, K, Aielli, G, Allanach, BC, Alvarez-Muñiz, J, Antonelli, M, Aschenauer, EC, Asner, DM, Assamagan, K, Baer, H, Banerjee, Sw, Barnett, RM, Baudis, L, Bauer, CW, Beatty, JJ, Beringer, J, Bettini, A, Biebel, O, Black, KM, Blucher, E, Bonventre, R, Briere, RA, Buckley, A, Burkert, VD, Bychkov, MA, Cahn, RN, Cao, Z, Carena, M, Casarosa, G, Ceccucci, A, Cerri, A, Chivukula, RS, Cowan, G, Cranmer, K, Crede, V, Cremonesi, O, D’Ambrosio, G, Damour, T, de Florian, D, de Gouvêa, A, DeGrand, T, Demers, S, Demiragli, Z, Dobrescu, BA, D’Onofrio, M, Doser, M, Dreiner, HK, Eerola, P, Egede, U, Eidelman, S, El-Khadra, AX, Ellis, J, Eno, SC, Erler, J, Ezhela, VV, Fava, A, Fetscher, W, Fields, BD, Freitas, A, Gallagher, H, Gershon, T, Gershtein, Y, Gherghetta, T, Gonzalez-Garcia, MC, Goodman, M, Grab, C, Gritsan, AV, Grojean, C, Groom, DE, Grünewald, M, Gurtu, A, Haber, HE, Hamel, M, Hashimoto, S, Hayato, Y, Hebecker, A, Heinemeyer, S, Hikasa, K, Hisano, J, Höcker, A, Holder, J, Hsu, L, Huston, J, Hyodo, T, Ianni, Al, Kado, M, and Karliner, M
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Nuclear and Plasma Physics ,Particle and High Energy Physics ,Physical Sciences - Abstract
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,717 new measurements from 869 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Most of the 120 reviews are updated, including many that are heavily revised. The Review is divided into two volumes. Volume 1 includes the Summary Tables and 97 review articles. Volume 2 consists of the Particle Listings and contains also 23 reviews that address specific aspects of the data presented in the Listings. The complete Review (both volumes) is published online on the website of the Particle Data Group (pdg.lbl.gov) and in a journal. Volume 1 is available in print as the PDG Book. A Particle Physics Booklet with the Summary Tables and essential tables, figures, and equations from selected review articles is available in print, as a web version optimized for use on phones, and as an Android app. The 2024 edition of the Review of Particle Physics should be cited as: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)
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- 2024
28. From pixels to planning: scale-free active inference
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Friston, Karl, Heins, Conor, Verbelen, Tim, Da Costa, Lancelot, Salvatori, Tommaso, Markovic, Dimitrije, Tschantz, Alexander, Koudahl, Magnus, Buckley, Christopher, and Parr, Thomas
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Computer Science - Machine Learning ,Quantitative Biology - Neurons and Cognition ,92 ,F.1.1 - Abstract
This paper describes a discrete state-space model -- and accompanying methods -- for generative modelling. This model generalises partially observed Markov decision processes to include paths as latent variables, rendering it suitable for active inference and learning in a dynamic setting. Specifically, we consider deep or hierarchical forms using the renormalisation group. The ensuing renormalising generative models (RGM) can be regarded as discrete homologues of deep convolutional neural networks or continuous state-space models in generalised coordinates of motion. By construction, these scale-invariant models can be used to learn compositionality over space and time, furnishing models of paths or orbits; i.e., events of increasing temporal depth and itinerancy. This technical note illustrates the automatic discovery, learning and deployment of RGMs using a series of applications. We start with image classification and then consider the compression and generation of movies and music. Finally, we apply the same variational principles to the learning of Atari-like games., Comment: 64 pages, 28 figures
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- 2024
29. The Chemical Diversity of the Metal-Poor Milky Way
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Buckley, Nicole, Das, Payel, Jofré, Paula, Yates, Robert M., and Hawkins, Keith
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Astrophysics - Astrophysics of Galaxies - Abstract
We present a detailed study of the chemical diversity of the metal-poor Milky Way (MW) using data from the GALAH DR3 survey. Considering 17 chemical abundances relative to iron ([X/Fe]) for 9,923 stars, we employ Principal Component Analysis (PCA) and Extreme Deconvolution (XD) to identify 10 distinct stellar groups. This approach, free from chemical or dynamical cuts, reveals known populations, including the accreted halo, thick disc, thin disc, and in-situ halo. The thick disc is characterised by multiple substructures, suggesting it comprises stars formed in diverse environments. Our findings highlight the limited discriminatory power of magnesium in separating accreted and disc stars. Elements such as Ba, Al, Cu, and Sc are critical in distinguishing disc from accreted stars, while Ba, Y, Eu and Zn differentiate disc and accreted stars from the in-situ halo. This study demonstrates the potential power of combining a latent space representation of the data (PCA) with a clustering algorithm (XD) in Galactic archaeology, in providing new insights into the galaxy's assembly and evolutionary history.
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- 2024
30. Two-dimensional motion of an impurity under dynamic light-induced dipole forces in an atomic subwavelength array
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Buckley-Bonanno, Samuel, Ostermann, Stefan, Wang, Yidan, and Yelin, Susanne F.
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Quantum Physics - Abstract
Long-range dipole-dipole interactions in subwavelength arrays of quantum emitters involve virtual photon exchange processes that impart forces on the emitters due to the imposed photon recoil. We perform a semi-classical analysis of the dynamics of an impurity allowed to freely move through a subwavelength array of atoms in different parameter regimes. We numerically solve the coupled set of equations between motional and spin degrees of freedom to elucidate the possible impurity trajectories realizable in this system. We find that the impurity can maintain quasi-stable orbits within the plaquette for long times. The regions through which these orbits pass are strongly dependent on the chosen atomic transition dipole moment. We further provide intuition for our findings based on a simplified model, where the lattice dynamics is adiabatically eliminated. As a final point of analysis, we also take the motional degrees of freedom of the lattice atoms into account, and study the polaron-like excitation induced in the kinetic state of the lattice by the impurity., Comment: 11 pages, 7 figures
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- 2024
31. Spectro-photometric follow up of the outbursting AM CVn system ASASSN-21br
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Painter, S., Aydi, E., Motsoaledi, M., Sokolovsky, K. V., Strader, J., Buckley, D. A. H., Kochanek, C. S., Maccarone, T. J., Mukai, K., Shappee, B. J., and Stanek, K. Z.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on spectroscopic and photometric observations of the AM CVn system ASASSN-21br, which was discovered in outburst by the All-Sky Automated Survey for Supernovae in February 2021. The outburst lasted for around three weeks, and exhibited a pronounced brightness dip for $\approx$ 4 days, during which the spectra showed a sudden transition from emission- to absorption-line dominated. Only $\approx$ 60 AM CVn systems with derived orbital periods are found in the Galaxy, therefore increasing the sample of AM CVn systems with known orbital periods is of tremendous importance to (1) constrain the physical mechanisms of their outbursts and (2) establish a better understanding of the low-frequency background noise of future gravitational wave surveys. Time-resolved photometry taken during the outburst of ASASSN-21br showed modulation with a period of around 36.65 minutes, which is likely the superhump or orbital period of the system. Time-resolved spectroscopy taken with the Southern African Large Telescope did not show any sign of periodicity in the He I absorption lines. This is possibly due to the origin of these lines in the outbursting accretion disc, which makes it challenging to retrieve periodicity from the spectral lines. Future follow up spectral observations during quiescence might allow us better constrain the orbital period of ASASSN-21br., Comment: 14 pages, 13 figures, accepted at MNRAS
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- 2024
32. Rapid Mid-Infrared Spectral-Timing with JWST. I. The prototypical black hole X-ray Binary GRS 1915+105 during a MIR-bright and X-ray-obscured state
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Gandhi, P., Borowski, E. S., Byrom, J., Hynes, R. I., Maccarone, T. J., Shaw, A. W., Adegoke, O. K., Altamirano, D., Baglio, M. C., Bhargava, Y., Britt, C. T., Buckley, D. A. H., Buisson, D. J. K., Casella, P., Segura, N. Castro, Charles, P. A., Corral-Santana, J. M., Dhillon, V. S., Fender, R., Gúrpide, A., Heinke, C. O., Igl, A. B., Knigge, C., Markoff, S., Mastroserio, G., McCollough, M. L., Middleton, M., Miller, J. M., Miller-Jones, J. C. A., Motta, S. E., Paice, J. A., Pawar, D. D., Plotkin, R. M., Pradhan, P., Ressler, M. E., Russell, D. M., Russell, T. D., Santos-Sanz, P., Shahbaz, T., Sivakoff, G. R., Steeghs, D., Tetarenko, A. J., Tomsick, J. A., Vincentelli, F. M., George, M., Gurwell, M., and Rao, R.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We present mid-infrared (MIR) spectral-timing measurements of the prototypical Galactic microquasar GRS 1915+105. The source was observed with the Mid-Infrared Instrument (MIRI) onboard JWST in June 2023 at a MIR luminosity L(MIR)~10^{36} erg/s exceeding past IR levels by about a factor of 10. By contrast, the X-ray flux is much fainter than the historical average, in the source's now-persistent 'obscured' state. The MIRI low-resolution spectrum shows a plethora of emission lines, the strongest of which are consistent with recombination in the hydrogen Pfund (Pf) series and higher. Low amplitude (~1%) but highly significant peak-to-peak photometric variability is found on timescales of ~1,000 s. The brightest Pf(6-5) emission line lags the continuum. Though difficult to constrain accurately, this lag is commensurate with light-travel timescales across the outer accretion disc or with expected recombination timescales inferred from emission line diagnostics. Using the emission line as a bolometric indicator suggests a moderate (~5-30% Eddington) intrinsic accretion rate. Multiwavelength monitoring shows that JWST caught the source close in-time to unprecedentedly bright MIR and radio long-term flaring. Assuming a thermal bremsstrahlung origin for the MIRI continuum suggests an unsustainably high mass-loss rate during this time unless the wind remains bound, though other possible origins cannot be ruled out. PAH features previously detected with Spitzer are now less clear in the MIRI data, arguing for possible destruction of dust in the interim. These results provide a preview of new parameter space for exploring MIR spectral-timing in XRBs and other variable cosmic sources on rapid timescales., Comment: Dedicated to the memory of our colleague, Tomaso Belloni. Submitted 2024 June 21; Comments welcome
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- 2024
33. The optical spectropolarimetric behaviour of a selection of high-energy blazars
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Barnard, J., van Soelen, B., Acharya, S., Böttcher, M., Britto, R. J., Cooper, J., Buckley, D. A. H., Martin-Carrillo, A., Vaidya, B., van der Westhuizen, I. P., and Zacharias, M.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
At optical/ultraviolet energies, blazars display an underlying thermal (unpolarized) contribution from the accretion disc, torus and line emitting regions, diluting the polarized emission from the jet-component. Optical polarimetry can be used to disentangle the thermal and non-thermal components, and place constraints on the particle populations and acceleration mechanisms responsible for the non-thermal emission. We present the results of a linear optical spectropolarimetric observing campaign of 18 blazars (6 BLLs and 12 FSRQs) undertaken with the Southern African Large Telescope between 2016 and 2022. This was done to observe these systems during flaring states, as well as long term monitoring of PKS1510-089, AP Lib and PKS 1034-293. The observations traced the frequency dependence of the degree and angle of polarization, as well as changes in the spectral line strengths. We investigated possible correlations between the polarization and other observed characteristics for the sources. While an indication of correlation was found between the frequency dependence and the average level of polarization for some sources, a correlation was not found for the population as a whole. These results highlight that continuous observations and in-depth modelling of polarization and its frequency dependence is required to obtain a more holistic view of TeV blazars., Comment: 17 pages, 21 figures, 3 tables, accepted for publication in MNRAS
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- 2024
34. Uniform Sampling and Visualization of 3D Reluctant Walks
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Buckley, Benjamin and Mishna, Marni
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Computer Science - Discrete Mathematics - Abstract
A family of walks confined to the first orthant whose defining stepset has drift outside of the region can be challenging to sample uniformly at random for large lengths. We address this by generalizing the 2D walk sampler of Lumbroso et al. to handle 3D walks restricted to the first orthant. The sampler includes a visualizer and means to animate the walks., Comment: In Proceedings GASCom 2024, arXiv:2406.14588
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- 2024
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35. Dark Energy Survey Year 3 Results: Cosmology from galaxy clustering and galaxy-galaxy lensing in harmonic space
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Faga, L., Andrade-Oliveira, F., Camacho, H., Rosenfeld, R., Lima, M., Doux, C., Fang, X., Prat, J., Porredon, A., Aguena, M., Alarcon, A., Allam, S., Alves, O., Amon, A., Avila, S., Bacon, D., Bechtol, K., Becker, M. R., Bernstein, G. M., Bocquet, S., Brooks, D., Buckley-Geer, E., Campos, A., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Castander, F. J., Cawthon, R., Chang, C., Chen, R., Choi, A., Cordero, J., Crocce, M., da Costa, L. N., Pereira, M. E. S., DeRose, J., Diehl, H. T., Dodelson, S., Drlica-Wagner, A., Elvin-Poole, J., Everett, S., Ferrero, I., Ferté, A., Flaugher, B., Fosalba, P., Frieman, J., García-Bellido, J., Gatti, M., Gaztanaga, E., Giannini, G., Gruen, D., Gruendl, R. A., Gutierrez, G., Harrison, I., Hinton, S. R., Hollowood, D. L., Honscheid, K., Huterer, D., James, D. J., Jarvis, M., Jeltema, T., Kuehn, K., Lahav, O., Lee, S., Lidman, C., MacCrann, N., Marshall, J. L., McCullough, J., Mena-Fernández, J., Miquel, R., Myles, J., Navarro-Alsina, A., Palmese, A., Pandey, S., Paterno, M., Pieres, A., Malagón, A. A. Plazas, Raveri, M., Rodriguez-Monroy, M., Rollins, R. P., Ross, A. J., Rykoff, E. S., Samuroff, S., Sánchez, C., Sanchez, E., Cid, D. Sanchez, Schubnell, M., Secco, L. F., Sevilla-Noarbe, I., Sheldon, E., Shin, T., Smith, M., Soares-Santos, M., Suchyta, E., Swanson, M. E. C., Tarle, G., Thomas, D., Troxel, M. A., Tutusaus, I., Weaverdyck, N., Wiseman, P., Yanny, B., and Yin, B.
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present the joint tomographic analysis of galaxy-galaxy lensing and galaxy clustering in harmonic space, using galaxy catalogues from the first three years of observations by the Dark Energy Survey (DES Y3). We utilise the redMaGiC and MagLim catalogues as lens galaxies and the METACALIBRATION catalogue as source galaxies. The measurements of angular power spectra are performed using the pseudo-$C_\ell$ method, and our theoretical modelling follows the fiducial analyses performed by DES Y3 in configuration space, accounting for galaxy bias, intrinsic alignments, magnification bias, shear magnification bias and photometric redshift uncertainties. We explore different approaches for scale cuts based on non-linear galaxy bias and baryonic effects contamination. Our fiducial covariance matrix is computed analytically, accounting for mask geometry in the Gaussian term, and including non-Gaussian contributions and super-sample covariance terms. To validate our harmonic space pipelines and covariance matrix, we used a suite of 1800 log-normal simulations. We also perform a series of stress tests to gauge the robustness of our harmonic space analysis. In the $\Lambda$CDM model, the clustering amplitude $S_8 =\sigma_8(\Omega_m/0.3)^{0.5}$ is constrained to $S_8 = 0.704\pm 0.029$ and $S_8 = 0.753\pm 0.024$ ($68\%$ C.L.) for the redMaGiC and MagLim catalogues, respectively. For the $w$CDM, the dark energy equation of state is constrained to $w = -1.28 \pm 0.29$ and $w = -1.26^{+0.34}_{-0.27}$, for redMaGiC and MagLim catalogues, respectively. These results are compatible with the corresponding DES Y3 results in configuration space and pave the way for harmonic space analyses using the DES Y6 data., Comment: To be submitted to MNRAS
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- 2024
36. Spin polarisation and non-isotropic effective mass in the conduction band of GdN
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Holmes-Hewett, W. F., Trewick, E. X. M., Trodahl, H. J., Buckley, R. G., and Ruck, B. J.
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Condensed Matter - Materials Science - Abstract
GdN is a ferromagnetic semiconductor which has seen increasing interest in the preceding decades particularly in the areas of spin- and superconducting- based electronics. Here we report a detailed computational study and optical spectroscopy study of the electronic structure of stoichiometric and nitrogen vacancy doped GdN. Based on our calculations we provide the effective mass tensor for undoped GdN, and some indicative values for electron doped GdN. Such a property is valuable as it can directly affect device design, and be directly measured experimentally to validate the existing computation results.
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- 2024
37. The Dark Energy Survey Supernova Program: Slow supernovae show cosmological time dilation out to $z \sim 1$
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White, R. M. T., Davis, T. M., Lewis, G. F., Brout, D., Galbany, L., Glazebrook, K., Hinton, S. R., Lee, J., Lidman, C., Möller, A., Sako, M., Scolnic, D., Smith, M., Sullivan, M., Sánchez, B. O., Shah, P., Vincenzi, M., Wiseman, P., Abbott, T. M. C., Aguena, M., Allam, S., Andrade-Oliveira, F., Asorey, J., Bacon, D., Bocquet, S., Brooks, D., Buckley-Geer, E., Burke, D. L., Rosell, A. Carnero, Carollo, D., Carretero, J., da Costa, L. N., Pereira, M. E. S., De Vicente, J., Desai, S., Diehl, H. T., Everett, S., Ferrero, I., Flaugher, B., Frieman, J., García-Bellido, J., Gaztanaga, E., Giannini, G., Gruendl, R. A., Hollowood, D. L., Honscheid, K., James, D. J., Kessler, R., Kuehn, K., Lahav, O., Lee, S., Lima, M., Marshall, J. L., Mena-Fernández, J., Miquel, R., Myles, J., Nichol, R. C., Ogando, R. L. C., Palmese, A., Pieres, A., Malagón, A. A. Plazas, Romer, A. K., Sanchez, E., Cid, D. Sanchez, Schubnell, M., Suchyta, E., Tarle, G., Tucker, B. E., Walker, A. R., and Weaverdyck, N.
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Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a precise measurement of cosmological time dilation using the light curves of 1504 type Ia supernovae from the Dark Energy Survey spanning a redshift range $0.1\lesssim z\lesssim 1.2$. We find that the width of supernova light curves is proportional to $(1+z)$, as expected for time dilation due to the expansion of the Universe. Assuming type Ia supernovae light curves are emitted with a consistent duration $\Delta t_{\rm em}$, and parameterising the observed duration as $\Delta t_{\rm obs}=\Delta t_{\rm em}(1+z)^b$, we fit for the form of time dilation using two methods. Firstly, we find that a power of $b \approx 1$ minimises the flux scatter in stacked subsamples of light curves across different redshifts. Secondly, we fit each target supernova to a stacked light curve (stacking all supernovae with observed bandpasses matching that of the target light curve) and find $b=1.003\pm0.005$ (stat) $\pm\,0.010$ (sys). Thanks to the large number of supernovae and large redshift-range of the sample, this analysis gives the most precise measurement of cosmological time dilation to date, ruling out any non-time-dilating cosmological models at very high significance., Comment: 14 pages, 13 figures. Updated in response to reviewer feedback. Accepted for publication in the Monthly Notices of the Royal Astronomical Society (MNRAS)
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- 2024
38. The Dark Energy Survey Supernova Program: An updated measurement of the Hubble constant using the Inverse Distance Ladder
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Camilleri, R., Davis, T. M., Hinton, S. R., Armstrong, P., Brout, D., Galbany, L., Glazebrook, K., Lee, J., Lidman, C., Nichol, R. C., Sako, M., Scolnic, D., Shah, P., Smith, M., Sullivan, M., Sánchez, B. O., Vincenzi, M., Wiseman, P., Allam, S., Abbott, T. M. C., Aguena, M., Andrade-Oliveira, F., Asorey, J., Avila, S., Bacon, D., Bechtol, K., Bocquet, S., Brooks, D., Buckley-Geer, E., Burke, D. L., Rosell, A. Carnero, Carollo, D., Carretero, J., Castander, F. J., Conselice, C., da Costa, L. N., Pereira, M. E. S., Desai, S., Diehl, H. T., Everett, S., Ferrero, I., Flaugher, B., Frieman, J., García-Bellido, J., Gaztanaga, E., Giannini, G., Gruendl, R. A., Herner, K., Hollowood, D. L., Honscheid, K., Huterer, D., James, D. J., Kent, S., Kuehn, K., Lahav, O., Lee, S., Lewis, G. F., Lima, M., Marshall, J. L., Mena-Fernández, J., Miquel, R., Myles, J., Ogando, R. L. C., Palmese, A., Pieres, A., Malagón, A. A. Plazas, Romer, A. K., Roodman, A., Samuroff, S., Sanchez, E., Cid, D. Sanchez, Schubnell, M., Sevilla-Noarbe, I., Suchyta, E., Suntzeff, N., Swanson, M. E. C., Tarle, G., Tucker, B. E., Walker, A. R., and Weaverdyck, N.
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We measure the current expansion rate of the Universe, Hubble's constant $H_0$, by calibrating the absolute magnitudes of supernovae to distances measured by Baryon Acoustic Oscillations. This `inverse distance ladder' technique provides an alternative to calibrating supernovae using nearby absolute distance measurements, replacing the calibration with a high-redshift anchor. We use the recent release of 1829 supernovae from the Dark Energy Survey spanning $0.01\lt z \lt1.13$ anchored to the recent Baryon Acoustic Oscillation measurements from DESI spanning $0.30 \lt z_{\mathrm{eff}} \lt 2.33$. To trace cosmology to $z=0$, we use the third-, fourth- and fifth-order cosmographic models, which, by design, are agnostic about the energy content and expansion history of the universe. With the inclusion of the higher-redshift DESI-BAO data, the third-order model is a poor fit to both data sets, with the fourth-order model being preferred by the Akaike Information Criterion. Using the fourth-order cosmographic model, we find $H_0=67.19^{+0.66}_{-0.64}\mathrm{~km} \mathrm{~s}^{-1} \mathrm{~Mpc}^{-1}$, in agreement with the value found by Planck without the need to assume Flat-$\Lambda$CDM. However the best-fitting expansion history differs from that of Planck, providing continued motivation to investigate these tensions.
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- 2024
39. TDCOSMO. XVI. Measurement of the Hubble Constant from the Lensed Quasar WGD$\,$2038$-$4008
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Wong, Kenneth C., Dux, Frédéric, Shajib, Anowar J., Suyu, Sherry H., Millon, Martin, Mozumdar, Pritom, Wells, Patrick R., Agnello, Adriano, Birrer, Simon, Buckley-Geer, Elizabeth J., Courbin, Frédéric, Fassnacht, Christopher D., Frieman, Joshua, Galan, Aymeric, Lin, Huan, Marshall, Philip J., Poh, Jason, Schuldt, Stefan, Sluse, Dominique, and Treu, Tommaso
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Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
Time-delay cosmography is a powerful technique to constrain cosmological parameters, particularly the Hubble constant ($H_{0}$). The TDCOSMO collaboration is performing an ongoing analysis of lensed quasars to constrain cosmology using this method. In this work, we obtain constraints from the lensed quasar WGD 2038-4008 using new time-delay measurements and previous mass models by TDCOSMO. This is the first TDCOSMO lens to incorporate multiple lens modeling codes and the full time-delay covariance matrix into the cosmological inference. The models are fixed before the time delay is measured, and the analysis is performed blinded with respect to the cosmological parameters to prevent unconscious experimenter bias. We obtain $D_{\Delta t} = 1.68^{+0.40}_{-0.38}$ Gpc using two families of mass models, a power-law describing the total mass distribution, and a composite model of baryons and dark matter, although the composite model is disfavored due to kinematics constraints. In a flat $\Lambda$CDM cosmology, we constrain the Hubble constant to be $H_{0} = 65^{+23}_{-14}\, \rm km\ s^{-1}\,Mpc^{-1}$. The dominant source of uncertainty comes from the time delays, due to the low variability of the quasar. Future long-term monitoring, especially in the era of the Vera C. Rubin Observatory's Legacy Survey of Space and Time, could catch stronger quasar variability and further reduce the uncertainties. This system will be incorporated into an upcoming hierarchical analysis of the entire TDCOSMO sample, and improved time delays and spatially-resolved stellar kinematics could strengthen the constraints from this system in the future., Comment: 8 pages, 5 figures, 3 tables; accepted for publication in Astronomy & Astrophysics
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- 2024
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40. Thermalization and Criticality on an Analog-Digital Quantum Simulator
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Andersen, Trond I., Astrakhantsev, Nikita, Karamlou, Amir H., Berndtsson, Julia, Motruk, Johannes, Szasz, Aaron, Gross, Jonathan A., Schuckert, Alexander, Westerhout, Tom, Zhang, Yaxing, Forati, Ebrahim, Rossi, Dario, Kobrin, Bryce, Di Paolo, Agustin, Klots, Andrey R., Drozdov, Ilya, Kurilovich, Vladislav D., Petukhov, Andre, Ioffe, Lev B., Elben, Andreas, Rath, Aniket, Vitale, Vittorio, Vermersch, Benoit, Acharya, Rajeev, Beni, Laleh Aghababaie, Anderson, Kyle, Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Ballard, Brian, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Ben, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Das, Sayan, Debroy, Dripto M., De Lorenzo, Laura, Barba, Alexander Del Toro, Demura, Sean, Donohoe, Paul, Dunsworth, Andrew, Earle, Clint, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Faoro, Lara, Fatemi, Reza, Ferreira, Vinicius S., Burgos, Leslie Flores, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Gasca, Robert, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Habegger, Steve, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heslin, Stephen, Heu, Paula, Hill, Gordon, Hoffmann, Markus R., Huang, Hsin-Yuan, Huang, Trent, Huff, Ashley, Huggins, William J., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Jordan, Stephen, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Kechedzhi, Kostyantyn, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Langley, Brandon W., Laptev, Pavel, Lau, Kim-Ming, Guevel, Loïck Le, Ledford, Justin, Lee, Joonho, Lee, Kenny, Lensky, Yuri D., Lester, Brian J., Li, Wing Yan, Lill, Alexander T., Liu, Wayne, Livingston, William P., Locharla, Aditya, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Maloney, Ashley, Mandrà, Salvatore, Martin, Leigh S., Martin, Orion, Martin, Steven, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Miao, Kevin C., Mieszala, Amanda, Molina, Sebastian, Montazeri, Shirin, Morvan, Alexis, Movassagh, Ramis, Neill, Charles, Nersisyan, Ani, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, Niu, Murphy Yuezhen, Oliver, William D., Ottosson, Kristoffer, Pizzuto, Alex, Potter, Rebecca, Pritchard, Orion, Pryadko, Leonid P., Quintana, Chris, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Rocque, Charles, Rosenberg, Eliott, Rubin, Nicholas C., Saei, Negar, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Skruzny, Jindra, Small, Spencer, Smith, W. Clarke, Springer, Sofia, Sterling, George, Suchard, Jordan, Szalay, Marco, Sztein, Alex, Thor, Douglas, Torres, Alfredo, Torunbalci, M. Mert, Vaishnav, Abeer, Vdovichev, Sergey, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., White, Theodore, Wong, Kristi, Woo, Bryan W., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhu, Ningfeng, Zobrist, Nicholas, Neven, Hartmut, Babbush, Ryan, Boixo, Sergio, Hilton, Jeremy, Lucero, Erik, Megrant, Anthony, Kelly, Julian, Chen, Yu, Smelyanskiy, Vadim, Vidal, Guifre, Roushan, Pedram, Lauchli, Andreas M., Abanin, Dmitry A., and Mi, Xiao
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Quantum Physics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Strongly Correlated Electrons - Abstract
Understanding how interacting particles approach thermal equilibrium is a major challenge of quantum simulators. Unlocking the full potential of such systems toward this goal requires flexible initial state preparation, precise time evolution, and extensive probes for final state characterization. We present a quantum simulator comprising 69 superconducting qubits which supports both universal quantum gates and high-fidelity analog evolution, with performance beyond the reach of classical simulation in cross-entropy benchmarking experiments. Emulating a two-dimensional (2D) XY quantum magnet, we leverage a wide range of measurement techniques to study quantum states after ramps from an antiferromagnetic initial state. We observe signatures of the classical Kosterlitz-Thouless phase transition, as well as strong deviations from Kibble-Zurek scaling predictions attributed to the interplay between quantum and classical coarsening of the correlated domains. This interpretation is corroborated by injecting variable energy density into the initial state, which enables studying the effects of the eigenstate thermalization hypothesis (ETH) in targeted parts of the eigenspectrum. Finally, we digitally prepare the system in pairwise-entangled dimer states and image the transport of energy and vorticity during thermalization. These results establish the efficacy of superconducting analog-digital quantum processors for preparing states across many-body spectra and unveiling their thermalization dynamics.
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- 2024
41. The Data Acquisition System of the LZ Dark Matter Detector: FADR
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Aalbers, J., Akerib, D. S., Musalhi, A. K. Al, Alder, F., Amarasinghe, C. S., Ames, A., Anderson, T. J., Angelides, N., Araújo, H. M., Armstrong, J. E., Arthurs, M., Baker, A., Balashov, S., Bang, J., Barillier, E. E., Bargemann, J. W., Beattie, K., Benson, T., Bhatti, A., Biekert, A., Biesiadzinski, T. P., Birch, H. J., Bishop, E., Blockinger, G. M., Boxer, B., Brew, C. A. J., Brás, P., Buckley, J. H., Burdin, S., Buuck, M., Carmona-Benitez, M. C., Carter, M., Chawla, A., Chen, H., Cherwinka, J. J., Chin, Y. T., Chott, N. I., Converse, M. V., Cottle, A., Cox, G., Curran, D., Dahl, C. E., David, A., Delgaudio, J., Dey, S., de Viveiros, L., Di Felice, L., Dimino, T., Ding, C., Dobson, J. E. Y., Druszkiewicz, E., Eriksen, S. R., Fan, A., Fearon, N. M., Fieldhouse, N., Fiorucci, S., Flaecher, H., Fraser, E. D., Fruth, T. M. A., Gaitskell, R. J., Geffre, A., Gelfand, R., Genovesi, J., Ghag, C., Gibbons, R., Gokhale, S., Green, J., van der Grinten, M. G. D., Haiston, J. J., Hall, C. R., Han, S., Hartigan-O'Connor, E., Haselschwardt, S. J., Hernandez, M. A., Hertel, S. A., Heuermann, G., Homenides, G. J., Horn, M., Huang, D. Q., Hunt, D., Jacquet, E., James, R. S., Johnson, J., Kaboth, A. C., Kamaha, A. C., Kannichankandy, M., Khaitan, D., Khazov, A., Khurana, I., Kim, J., Kim, Y. D., Kingston, J., Kirk, R., Kodroff, D., Korley, L., Korolkova, E. V., Koyuncu, M., Kraus, H., Kravitz, S., Kreczko, L., Kudryavtsev, V. A., Leonard, D. S., Lesko, K. T., Levy, C., Lin, J., Lindote, A., Linehan, R., Lippincott, W. H., Loniewski, C., Lopes, M. I., Lorenzon, W., Lu, C., Luitz, S., Majewski, P. A., Manalaysay, A., Mannino, R. L., Maupin, C., McCarthy, M. E., McDowell, G., McKinsey, D. N., McLaughlin, J., Mclaughlin, J. B., McMonigle, R., Miller, E. H., Mizrachi, E., Monte, A., Monzani, M. E., Moongweluwan, M., Mendoza, J. D. Morales, Morrison, E., Mount, B. J., Murdy, M., Murphy, A. St. J., Naylor, A., Nelson, H. N., Neves, F., Nguyen, A., Nikoleyczik, J. A., Oh, H., Olcina, I., Olevitch, M. A., Oliver-Mallory, K. C., Orpwood, J., Palladino, K. J., Palmer, J., Pannifer, N. J., Parveen, N., Patton, S. J., Penning, B., Pereira, G., Perry, E., Pershing, T., Piepke, A., Qie, Y., Reichenbacher, J., Rhyne, C. A., Riffard, Q., Rischbieter, G. R. C., Riyat, H. S., Rosero, R., Rushton, T., Rynders, D., Santone, D., Sarkis, R., Sazzad, A. B. M. R., Schnee, R. W., Shaw, S., Shutt, T., Silk, J. J., Silva, C., Sinev, G., Siniscalco, J., Skulski, W., Smith, R., Solovov, V. N., Sorensen, P., Soria, J., Stancu, I., Stevens, A., Stifter, K., Suerfu, B., Sumner, T. J., Szydagis, M., Taylor, W. C., Tiedt, D. R., Timalsina, M., Tong, Z., Tovey, D. R., Tranter, J., Trask, M., Tripathi, M., Tronstad, D. R., Vacheret, A., Vaitkus, A. C., Vaitkus, J., Valentino, O., Velan, V., Wang, A., Wang, J. J., Wang, Y., Watson, J. R., Webb, R. C., Weeldreyer, L., Whitis, T. J., Williams, M., Wisniewski, W. J., Wolfs, F. L. H., Wolfs, J. D., Woodford, S., Woodward, D., Wright, C. J., Xia, Q., Xiang, X., Xu, J., Yeh, M., and Yin, J.
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Physics - Instrumentation and Detectors ,High Energy Physics - Experiment - Abstract
The Data Acquisition System (DAQ) for the LUX-ZEPLIN (LZ) dark matter detector is described. The signals from 745 PMTs, distributed across three subsystems, are sampled with 100-MHz 32-channel digitizers (DDC-32s). A basic waveform analysis is carried out on the on-board Field Programmable Gate Arrays (FPGAs) to extract information about the observed scintillation and electroluminescence signals. This information is used to determine if the digitized waveforms should be preserved for offline analysis. The system is designed around the Kintex-7 FPGA. In addition to digitizing the PMT signals and providing basic event selection in real time, the flexibility provided by the use of FPGAs allows us to monitor the performance of the detector and the DAQ in parallel to normal data acquisition. The hardware and software/firmware of this FPGA-based Architecture for Data acquisition and Realtime monitoring (FADR) are discussed and performance measurements are described., Comment: 18 pages, 24 figures
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- 2024
42. GDPR: Is it worth it? Perceptions of workers who have experienced its implementation
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Buckley, Gerard, Caulfield, Tristan, and Becker, Ingolf
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Computer Science - Computers and Society - Abstract
The General Data Protection Regulation (GDPR) remains the gold standard in privacy and security regulation. We investigate how the cost and effort required to implement GDPR is viewed by workers who have also experienced the regulations' benefits as citizens: is it worth it? In a multi-stage study, we survey N = 273 & 102 individuals who remained working in the same companies before, during, and after the implementation of GDPR. The survey finds that participants recognise their rights when prompted but know little about their regulator. They have observed concrete changes to data practices in their workplaces and appreciate the trade-offs. They take comfort that their personal data is handled as carefully as their employers' client data. The very people who comply with and execute the GDPR consider it to be positive for their company, positive for privacy and not a pointless, bureaucratic regulation. This is rare as it contradicts the conventional negative narrative about regulation. Policymakers may wish to build upon this public support while it lasts and consider early feedback from a similar dual professional-consumer group as the GDPR evolves.
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- 2024
43. A close binary lens revealed by the microlensing event Gaia20bof
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Bachelet, E., Rota, P., Bozza, V., Zielinski, P., Tsapras, Y., Hundertmark, M., Wambsganss, J., Wyrzykowski, L., Mikolajczyk, P. J., Street, R. A., Jaimes, R. Figuera, Cassan, A., Dominik, M., Buckley, D. A. H., Awiphan, S., Nakhaharutai, N., Zola, S., Rybicki, K. A., Gromadzki, M., Howil, K., Ihanec, N., Jablonska, M., Kruszynska, K., Pylypenko, U., Ratajczak, M., Sitek, M., and Rabus, M.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
During the last 25 years, hundreds of binary stars and planets have been discovered towards the Galactic Bulge by microlensing surveys. Thanks to a new generation of large-sky surveys, it is now possible to regularly detect microlensing events across the entire sky. The OMEGA Key Projet at the Las Cumbres Observatory carries out automated follow-up observations of microlensing events alerted by these surveys with the aim of identifying and characterizing exoplanets as well as stellar remnants. In this study, we present the analysis of the binary lens event Gaia20bof. By automatically requesting additional observations, the OMEGA Key Project obtained dense time coverage of an anomaly near the peak of the event, allowing characterization of the lensing system. The observed anomaly in the lightcurve is due to a binary lens. However, several models can explain the observations. Spectroscopic observations indicate that the source is located at $\le2.0$ kpc, in agreement with the parallax measurements from Gaia. While the models are currently degenerate, future observations, especially the Gaia astrometric time series as well as high-resolution imaging, will provide extra constraints to distinguish between them., Comment: Accepted in AJ
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- 2024
44. Optical spectroscopic and photometric classification of the X-ray transient EP240309a (EP J115415.8-501810) as an intermediate polar
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Potter, Stephen. B., Buckley, David A. H., Scaringi, S., Monageng, I. M., Egbo, Okwudili D., Charles, Philip A., Erasmus, N., van Gend, Carel, Loubser, Egan, Titus, Keegan, Rosie, Kathryn, Gajjar, Hitesh, Worters, H. L., Chandra, Sunil, Julie, R. P. M., and Hlakola, Moloko
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on optical follow-up observations of an X-ray source initially detected by the Einstein Probe mission. Our investigations categorize the source as an intermediate polar, a class of magnetic cataclysmic variables, exhibiting an orbital period of 3.7614(4) hours and a white dwarf spin period of 3.97 minutes. The orbital period was identified through TESS observations, while our high-speed photometric data, obtained using the 1.9m and Lesedi 1.0m telescopes at the South African Astronomical Observatory, revealed both the spin and beat periods. Additionally, we present orbitally phase-resolved spectroscopic observations using the 1.9m telescope, specifically centered on the Hbeta emission line, which reveal two emission components that exhibit Doppler variations throughout the orbital cycle., Comment: 5 pages, 9 figures accepted in MNRAS letters
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- 2024
45. The data acquisition system of the LZ dark matter detector: FADR
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Aalbers, J, Akerib, DS, Al Musalhi, AK, Alder, F, Amarasinghe, CS, Ames, A, Anderson, TJ, Angelides, N, Araújo, HM, Armstrong, JE, Arthurs, M, Baker, A, Balashov, S, Bang, J, Barillier, EE, Bargemann, JW, Beattie, K, Benson, T, Bhatti, A, Biekert, A, Biesiadzinski, TP, Birch, HJ, Bishop, E, Blockinger, GM, Boxer, B, Brew, CAJ, Brás, P, Buckley, JH, Burdin, S, Buuck, M, Carmona-Benitez, MC, Carter, M, Chawla, A, Chen, H, Cherwinka, JJ, Chin, YT, Chott, NI, Converse, MV, Cottle, A, Cox, G, Curran, D, Dahl, CE, David, A, Delgaudio, J, Dey, S, de Viveiros, L, Di Felice, L, Dimino, T, Ding, C, Dobson, JEY, Druszkiewicz, E, Eriksen, SR, Fan, A, Fearon, NM, Fieldhouse, N, Fiorucci, S, Flaecher, H, Fraser, ED, Fruth, TMA, Gaitskell, RJ, Geffre, A, Gelfand, R, Genovesi, J, Ghag, C, Gibbons, R, Gokhale, S, Green, J, van der Grinten, MGD, Haiston, JJ, Hall, CR, Han, S, Hartigan-O’Connor, E, Haselschwardt, SJ, Hernandez, MA, Hertel, SA, Heuermann, G, Homenides, GJ, Horn, M, Huang, DQ, Hunt, D, Jacquet, E, James, RS, Johnson, J, Kaboth, AC, Kamaha, AC, Kannichankandy, M, Khaitan, D, Khazov, A, Khurana, I, Kim, J, Kim, YD, Kingston, J, Kirk, R, Kodroff, D, Korley, L, Korolkova, EV, Koyuncu, M, Kraus, H, Kravitz, S, and Kreczko, L
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Nuclear and Plasma Physics ,Synchrotrons and Accelerators ,Physical Sciences ,Networking and Information Technology R&D (NITRD) ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Other Physical Sciences ,Nuclear & Particles Physics ,Nuclear and plasma physics - Abstract
The Data Acquisition System (DAQ) for the LUX-ZEPLIN (LZ) dark matter detector is described. The signals from 745 PMTs, distributed across three subsystems, are sampled with 100-MHz 32-channel digitizers (DDC-32s). A basic waveform analysis is carried out on the on-board Field Programmable Gate Arrays (FPGAs) to extract information about the observed scintillation and electroluminescence signals. This information is used to determine if the digitized waveforms should be preserved for offline analysis. The system is designed around the Kintex-7 FPGA. In addition to digitizing the PMT signals and providing basic event selection in real time, the flexibility provided by the use of FPGAs allows us to monitor the performance of the detector and the DAQ in parallel to normal data acquisition. The hardware and software/firmware of this FPGA-based Architecture for Data acquisition and Realtime monitoring (FADR) are discussed and performance measurements are described.
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- 2024
46. Qualitative Exploration toward the Development of a Parent-Rated Scale for Insomnia in Children with Autism Spectrum Disorder
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C. Sinha, L. Lecavalier, C. R. Johnson, C. Taylor, A. Mulligan, D. Buckley, M. L. Alder, and L. Scahill
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Toward the development of a new parent-rating for insomnia, this multi-site qualitative study explored sleep problems and related impacts in children with autism spectrum disorder (ASD) and their families. To ensure content validity of the measure, we conducted six focus groups with caregivers (N = 25) of 24 children (age 3 to 18 years) with ASD. Based on parent report, all children had a history of mild or greater insomnia. The focus group transcripts were systematically coded to identify major themes. Verbatim comments from caretakers were used to generate 134 candidate items. Further review by the research team and an expert panel followed by individual cognitive interviews with 12 parents reduced the item bank to 40. The thematic analysis of focus group transcripts identified 7 categories: (1) Trouble falling asleep; (2) trouble staying asleep; (3) early morning waking; (4) bedtime routines; (5) parental strategies for bedtime management; (6) impact of sleep problems on the child; and (7) impact of sleep problems on the family. The Flesch Kincaid Grade Level of the 40-item version was 7.2 (seventh grade reading level). Insomnia in children with ASD shares features in common with insomnia in the general pediatric population. However, perhaps owing to autistic features such as insistence on sameness, sensory sensitivities, communication impairments, insomnia in children with ASD appears to have unique behavioral manifestations. Content validity and item clarity of the 40-item bank were supported by expert panel review and cognitive interviews with caregivers of children with ASD.
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- 2024
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47. 2024 RECOVER Guidelines: Updated treatment recommendations for CPR in dogs and cats
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Burkitt‐Creedon, Jamie M, Boller, Manuel, Fletcher, Daniel J, Brainard, Benjamin M, Buckley, Gareth J, Epstein, Steven E, Fausak, Erik D, Hopper, Kate, Lane, Selena L, Rozanski, Elizabeth A, and Wolf, Jacob
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Veterinary Sciences ,Agricultural ,Veterinary and Food Sciences ,Dogs ,Animals ,Cats ,Cardiopulmonary Resuscitation ,Cat Diseases ,Dog Diseases ,Heart Arrest ,canine ,cardiopulmonary resuscitation ,clinical trials ,consensus guidelines ,critical care ,evidence-based medicine ,feline ,evidence‐based medicine ,Veterinary sciences - Abstract
ObjectiveAfter the 2012 Reassessment Campaign on Veterinary Resuscitation (RECOVER) CPR Guidelines, this is an update of evidence-based consensus guidelines for Basic Life Support (BLS), advanced life support (ALS), and periarrest monitoring.DesignThese RECOVER CPR Guidelines were generated using a modified version of the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system for evidence evaluation and translation of this evidence into clear and actionable clinical instructions. Prioritized clinical questions in the Population, Intervention, Comparator, and Outcome (PICO) format were used as the basis to conduct systematic literature searches by information specialists, to extract information from relevant publications, to assess this evidence for quality, and finally to translate the findings into treatment recommendations. These recommendations were reviewed by the RECOVER writing group and opened for comment by veterinary professionals for 4 weeks.SettingTransdisciplinary, international collaboration in university, specialty, and emergency practice.ResultsA total of 40 worksheets were prepared to evaluate questions across the 3 domains of BLS, ALS and Monitoring, resulting in 90 individual treatment recommendations. High-dose epinephrine is no longer recommended, and atropine, if used, is only administered once. Bag-mask ventilation is prioritized over mouth-to-nose ventilation in nonintubated animals. In addition, an algorithm for initial assessment, an updated CPR algorithm, a rhythm diagnosis tool, and an updated drug dosing table are provided.ConclusionsWhile the majority of the BLS and ALS recommendations remain unchanged, some noteworthy changes were made due to new evidence that emerged over the past 10 years. Indirectness of evidence remains the largest impediment to the certainty of guidelines formulation and underscores an urgent need for more studies in the target species of dogs and cats.
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- 2024
48. 2024 RECOVER Guidelines: Advanced Life Support. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR
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Wolf, Jacob, Buckley, Gareth J, Rozanski, Elizabeth A, Fletcher, Daniel J, Boller, Manuel, Burkitt‐Creedon, Jamie M, Weigand, Kelly A, Crews, Molly, Fausak, Erik D, and Authors, and the RECOVER Advanced Life Support Domain Worksheet
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Veterinary Sciences ,Agricultural ,Veterinary and Food Sciences ,Animals ,Dogs ,Cats ,Dog Diseases ,Cardiopulmonary Resuscitation ,Cat Diseases ,Veterinary Medicine ,Heart Arrest ,canine ,cardiopulmonary resuscitation ,clinical trials ,consensus guidelines ,critical care ,evidence-based medicine ,feline ,and the RECOVER Advanced Life Support Domain Worksheet Authors ,evidence‐based medicine ,Veterinary sciences - Abstract
ObjectiveTo systematically review the evidence and devise clinical recommendations on advanced life support (ALS) in dogs and cats and to identify critical knowledge gaps.DesignStandardized, systematic evaluation of literature pertinent to ALS following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by ALS Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization.SettingTransdisciplinary, international collaboration in university, specialty, and emergency practice.ResultsSeventeen questions pertaining to vascular access, vasopressors in shockable and nonshockable rhythms, anticholinergics, defibrillation, antiarrhythmics, and adjunct drug therapy as well as open-chest CPR were reviewed. Of the 33 treatment recommendations formulated, 6 recommendations addressed the management of patients with nonshockable arrest rhythms, 10 addressed shockable rhythms, and 6 provided guidance on open-chest CPR. We recommend against high-dose epinephrine even after prolonged CPR and suggest that atropine, when indicated, is used only once. In animals with a shockable rhythm in which initial defibrillation was unsuccessful, we recommend doubling the defibrillator dose once and suggest vasopressin (or epinephrine if vasopressin is not available), esmolol, lidocaine in dogs, and/or amiodarone in cats.ConclusionsThese updated RECOVER ALS guidelines clarify the approach to refractory shockable rhythms and prolonged CPR. Very low quality of evidence due to absence of clinical data in dogs and cats continues to compromise the certainty with which recommendations can be made.
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- 2024
49. MDA5-autoimmunity and interstitial pneumonitis contemporaneous with the COVID-19 pandemic (MIP-C)
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David, Paula, Sinha, Saptarshi, Iqbal, Khizer, De Marco, Gabriele, Taheri, Sahar, McLaren, Ella, Maisuria, Sheetal, Arumugakani, Gururaj, Ash, Zoe, Buckley, Catrin, Coles, Lauren, Hettiarachchi, Chamila, Payne, Emma, Savic, Sinisa, Smithson, Gayle, Slade, Maria, Shah, Rahul, Marzo-Ortega, Helena, Keen, Mansoor, Lawson, Catherine, Mclorinan, Joanna, Nizam, Sharmin, Reddy, Hanu, Sharif, Omer, Sultan, Shabina, Tran, Gui, Wood, Mark, Wood, Samuel, Ghosh, Pradipta, and McGonagle, Dennis
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Biomedical and Clinical Sciences ,Clinical Sciences ,Lung ,Genetics ,Autoimmune Disease ,Rare Diseases ,Emerging Infectious Diseases ,Coronaviruses ,Infectious Diseases ,2.1 Biological and endogenous factors ,Good Health and Well Being ,Humans ,COVID-19 ,Interferon-Induced Helicase ,IFIH1 ,Lung Diseases ,Interstitial ,SARS-CoV-2 ,Male ,Female ,Autoimmunity ,Middle Aged ,Autoantibodies ,Aged ,Retrospective Studies ,Pandemics ,Dermatomyositis ,Adult ,Interstitial lung disease ,Autoimmune Raynauds ,Autoimmune rashes ,MDA5-autoimmunity and interstitial pneumonitis contemporaneous with the COVID-19 ,Coronavirus-19 ,Melanoma differentiation-associated protein-5 ,Public Health and Health Services ,Clinical sciences ,Epidemiology - Abstract
BackgroundAnti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5+-DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 is an RNA sensor and a key pattern recognition receptor for the SARS-CoV-2 virus.MethodsThis is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018 and December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5+-DM outbreak.FindingsSixty new anti-MDA5+, but not other MSAs surged between 2020 and 2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response.InterpretationA distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.FundingThis work was supported in part by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC), and in part by the National Institutes of Health (NIH) grant R01-AI155696 and pilot awards from the UC Office of the President (UCOP)-RGPO (R00RG2628, R00RG2642 and R01RG3780) to P.G. S.S was supported in part by R01-AI141630 (to P.G) and in part through funds from the American Association of Immunologists (AAI) Intersect Fellowship Program for Computational Scientists and Immunologists.
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- 2024
50. MP64-15 OUTCOMES FOLLOWING SURGERY FOR ADULT ACQUIRED BURIED PENIS: A MULTI-INSTITUTIONAL RETROSPECTIVE INVESTIGATION UTILIZING A NOVEL STAGING SYSTEM BASED ON THE STANDARDIZED EVALUATION OF THE PENIS, ABDOMEN AND SCROTUM
- Author
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Jamil, Marcus L, Pagura, Elizabeth J, Rozanski, Alexander, Ashouri, Kenan A, Jones, Charles P, Cho, Eric, Groves, Shawn, Alsikafi, Nejd, Breyer, Benjamin, Broghammer, Joshua, Buckley, Jill, Elliott, Sean, Erickson, Bradley A, Myers, Jeremy, Peterson, Andrew C, Rourke, Keith, Voelzke, Brian, Zhao, Lee, and Vanni, Alex J
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Clinical Research - Published
- 2024
Catalog
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