139,773 results on '"Schreiber A"'
Search Results
2. Super-$\mathrm{Lie}_\infty$ T-Duality and M-Theory
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Giotopoulos, Grigorios, Sati, Hisham, and Schreiber, Urs
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High Energy Physics - Theory ,Mathematical Physics ,Mathematics - Differential Geometry - Abstract
Super $L_\infty$-algebras unify extended super-symmetry with rational classifying spaces for higher flux densities: The super-invariant super-fluxes which control super $p$-branes and their supergravity target super-spaces are, together with their (non-linear) Bianchi identities, neatly encoded in (non-abelian) super-$L_\infty$ cocycles. These are the rational shadows of flux-quantization laws (in ordinary cohomology, K-theory, Cohomotopy, iterated K-theory, etc). We first review, in streamlined form while filling some previous gaps, double-dimensional reduction/oxidation and 10D superspace T-duality along higher-dimensional super-tori. We do so tangent super-space wise, by viewing it as an instance of adjunctions (dualities) between super-$L_\infty$-extensions and -cyclifications, applied to the avatar super-flux densities of 10D supergravity. In particular, this yields a derivation, at the rational level, of the traditional laws of "topological T-duality" from the super-$L_\infty$ structure of type II superspace. At this level, we also discuss a higher categorical analog of T-duality involving M-branes. Then, by considering super-space T-duality along all 1+9 spacetime dimensions while retaining the 11th dimension as in F-theory, we find the M-algebra appearing as the complete brane-charge extension of the fully T-doubled/correspondence super-spacetime. On this backdrop, we recognize the "decomposed" M-theory 3-form on the "hidden M-algebra" as an M-theoretic lift of the Poincar\'e super 2-form that controls superspace T-duality as the integral kernel of the super Fourier-Mukai transform. This provides the super-space structure of an M-theory lift of the doubled/correspondence space geometry, which controls T-duality., Comment: 90 pages, some figures
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- 2024
3. SMILE-UHURA Challenge -- Small Vessel Segmentation at Mesoscopic Scale from Ultra-High Resolution 7T Magnetic Resonance Angiograms
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Chatterjee, Soumick, Mattern, Hendrik, Dörner, Marc, Sciarra, Alessandro, Dubost, Florian, Schnurre, Hannes, Khatun, Rupali, Yu, Chun-Chih, Hsieh, Tsung-Lin, Tsai, Yi-Shan, Fang, Yi-Zeng, Yang, Yung-Ching, Huang, Juinn-Dar, Xu, Marshall, Liu, Siyu, Ribeiro, Fernanda L., Bollmann, Saskia, Chintalapati, Karthikesh Varma, Radhakrishna, Chethan Mysuru, Kumara, Sri Chandana Hudukula Ram, Sutrave, Raviteja, Qayyum, Abdul, Mazher, Moona, Razzak, Imran, Rodero, Cristobal, Niederren, Steven, Lin, Fengming, Xia, Yan, Wang, Jiacheng, Qiu, Riyu, Wang, Liansheng, Panah, Arya Yazdan, Jurdi, Rosana El, Fu, Guanghui, Arslan, Janan, Vaillant, Ghislain, Valabregue, Romain, Dormont, Didier, Stankoff, Bruno, Colliot, Olivier, Vargas, Luisa, Chacón, Isai Daniel, Pitsiorlas, Ioannis, Arbeláez, Pablo, Zuluaga, Maria A., Schreiber, Stefanie, Speck, Oliver, and Nürnberger, Andreas
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Electrical Engineering and Systems Science - Image and Video Processing ,Computer Science - Artificial Intelligence ,Computer Science - Computer Vision and Pattern Recognition - Abstract
The human brain receives nutrients and oxygen through an intricate network of blood vessels. Pathology affecting small vessels, at the mesoscopic scale, represents a critical vulnerability within the cerebral blood supply and can lead to severe conditions, such as Cerebral Small Vessel Diseases. The advent of 7 Tesla MRI systems has enabled the acquisition of higher spatial resolution images, making it possible to visualise such vessels in the brain. However, the lack of publicly available annotated datasets has impeded the development of robust, machine learning-driven segmentation algorithms. To address this, the SMILE-UHURA challenge was organised. This challenge, held in conjunction with the ISBI 2023, in Cartagena de Indias, Colombia, aimed to provide a platform for researchers working on related topics. The SMILE-UHURA challenge addresses the gap in publicly available annotated datasets by providing an annotated dataset of Time-of-Flight angiography acquired with 7T MRI. This dataset was created through a combination of automated pre-segmentation and extensive manual refinement. In this manuscript, sixteen submitted methods and two baseline methods are compared both quantitatively and qualitatively on two different datasets: held-out test MRAs from the same dataset as the training data (with labels kept secret) and a separate 7T ToF MRA dataset where both input volumes and labels are kept secret. The results demonstrate that most of the submitted deep learning methods, trained on the provided training dataset, achieved reliable segmentation performance. Dice scores reached up to 0.838 $\pm$ 0.066 and 0.716 $\pm$ 0.125 on the respective datasets, with an average performance of up to 0.804 $\pm$ 0.15.
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- 2024
4. Disk kinematics at high redshift: DysmalPy's extension to 3D modeling and comparison with different approaches
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Lee, Lilian L., Schreiber, Natascha M. Förster, Price, Sedona H., Liu, Daizhong, Genzel, Reinhard, Davies, Richard I, Tacconi, Linda J., Shimizu, Thomas T., Shachar, Amit Nestor, Salcedo, Juan M. Espejo, Pastras, Stavros, Wuyts, Stijn, Lutz, Dieter, Renzini, Alvio, Übler, Hannah D., Herrera-Camus, Rodrigo, and Sternberg, Amiel
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Astrophysics - Astrophysics of Galaxies - Abstract
Spatially-resolved emission line kinematics are invaluable to investigating fundamental galaxy properties and have become increasingly accessible for galaxies at $z\gtrsim0.5$ through sensitive near-infrared imaging spectroscopy and millimeter interferometry. Kinematic modeling is at the core of the analysis and interpretation of such data sets, which at high-z present challenges due to lower signal-to-noise ratio (S/N) and resolution compared to data of local galaxies. We present and test the 3D fitting functionality of DysmalPy, examining how well it recovers intrinsic disk rotation velocity and velocity dispersion, using a large suite of axisymmetric models, covering a range of galaxy properties and observational parameters typical of $z\sim1$-$3$ star-forming galaxies. We also compare DysmalPy's recovery performance to that of two other commonly used codes, GalPak3D and 3DBarolo, which we use in turn to create additional sets of models to benchmark DysmalPy. Over the ranges of S/N, resolution, mass, and velocity dispersion explored, the rotation velocity is accurately recovered by all tools. The velocity dispersion is recovered well at high S/N, but the impact of methodology differences is more apparent. In particular, template differences for parametric tools and S/N sensitivity for the non-parametric tool can lead to differences up to a factor of 2. Our tests highlight and the importance of deep, high-resolution data and the need for careful consideration of: (1) the choice of priors (parametric approaches), (2) the masking (all approaches) and, more generally, evaluating the suitability of each approach to the specific data at hand. This paper accompanies the public release of DysmalPy., Comment: 38 pages, 21 figures, accepted for publication in ApJ
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- 2024
5. To What Extent Does the Perceived Obesity Level of Humanoid Robots Affect People's Trust in Them?
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Yoscovich, Yoav, Schreiber, Amir, Hadar, Nir, and Mirsky, Reuth
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Computer Science - Robotics - Abstract
Despite obesity being widely discussed in the social sciences, the effect of a robot's perceived obesity level on trust is not covered by the field of HRI. While in research regarding humans, Body Mass Index (BMI) is commonly used as an indicator of obesity, this scale is completely irrelevant in the context of robots, so it is challenging to operationalize the perceived obesity level of robots; indeed, while the effect of robot's size (or height) on people's trust in it was addressed in previous HRI papers, the perceived obesity level factor has not been addressed. This work examines to what extent the perceived obesity level of humanoid robots affects people's trust in them. To test this hypothesis, we conducted a within-subjects study where, using an online pre-validated questionnaire, the subjects were asked questions while being presented with two pictures of humanoids, one with a regular obesity level and the other with a high obesity level. The results show that humanoid robots with lower perceived obesity levels are significantly more likely to be trusted., Comment: Accepted to "Designing Interactive Humanoids: Learning Tasks through Interaction with Humans'' workshop on Humanoids 2025
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- 2024
6. Atomic Clock Ensemble in Space
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Cacciapuoti, L., Busso, A., Jansen, R., Pataraia, S., Peignier, T., Weinberg, S., Crescence, P., Helm, A., Kehrer, J., Koller, S., Lachaud, R., Niedermaier, T., Esnault, F. -X., Massonnet, D., Goujon, D., Pittet, J., Perri, A., Wang, Q., Liu, S., Schaefer, W., Schwall, T., Prochazka, I., Schlicht, A., Schreiber, U., Laurent, P., Lilley, M., Wolf, P., and Salomon, C.
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General Relativity and Quantum Cosmology ,Astrophysics - Instrumentation and Methods for Astrophysics ,Physics - Instrumentation and Detectors - Abstract
The Atomic Clock Ensemble in Space (ACES) mission is developing high performance clocks and links for space to test Einstein's theory of general relativity. From the International Space Station, the ACES payload will distribute a clock signal with fractional frequency stability and accuracy of 1E-16 establishing a worldwide network to compare clocks in space and on the ground. ACES will provide an absolute measurement of Einstein's gravitational redshift, it will search for time variations of fundamental constants, contribute to test topological dark matter models, and perform Standard Model Extension tests. Moreover, the ground clocks connected to the ACES network will be compared over different continents and used to measure geopotential differences at the clock locations. After solving some technical problems, the ACES flight model is now approaching its completion. System tests involving the laser-cooled Cs clock PHARAO, the active H-maser SHM and the on-board frequency comparator FCDP have measured the performance of the clock signal delivered by ACES. The ACES microwave link MWL is currently under test. The single-photon avalanche detector of the optical link ELT has been tested and will now be integrated in the ACES payload. The ACES mission concept, its scientific objectives, and the recent test results are discussed here together with the major milestones that will lead us to the ACES launch., Comment: 12 pages, 8 figures
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- 2024
7. The M-algebra completes the hierarchy of Super-Exceptional Tangent Spaces
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Giotopoulos, Grigorios, Sati, Hisham, and Schreiber, Urs
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High Energy Physics - Theory ,General Relativity and Quantum Cosmology ,Mathematical Physics ,Mathematics - Differential Geometry - Abstract
The conjectured symmetries of M-theory famously involve (1.) brane-extended super-symmetry (the M-algebra) and (2.) exceptional duality-symmetry (the $\mathfrak{e}_{11}$-algebra); but little attention has been given to their inevitable combination. In this little note, we highlight (by combining results available in the literature) that the $local$ exceptional duality-symmetry (the hyperbolic involutary $\mathfrak{k}_{1,10} \subset \mathfrak{e}_{11}$) acts on the M-algebra, through the "brane-rotating symmetry" $\mathfrak{sl}_{32}$, in a way which extends the known hierarchy of finite-dimensional $n$-exceptional tangent spaces compatibly beyond the traditional bound of $n \leq 7$ all the way to $n = 11$., Comment: 13 pages
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- 2024
8. Main sequence dynamo magnetic fields emerging in the white dwarf phase
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Camisassa, Maria, Fuentes, J. R., Schreiber, Matthias R., Rebassa-Mansergas, Alberto, Torres, Santiago, Raddi, Roberto, and Dominguez, Inma
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Recent observations of volume-limited samples of magnetic white dwarfs (WD) have revealed a higher incidence of magnetism in older WDs. Specifically, these studies indicate that magnetism is more prevalent in WDs with fully or partially crystallized cores compared to those with entirely liquid cores. This has led to the recognition of a crystallization-driven dynamo as an important mechanism for explaining magnetism in isolated WDs. However, recent simulations challenged the capability of this mechanism to match both the incidence of magnetism and the field strengths detected in WDs. In this letter, we explore an alternative hypothesis for the surface emergence of magnetic fields in isolated WDs. WDs with masses $\gtrsim 0.55 M_\odot$ are the descendants of main-sequence stars with convective cores capable of generating strong dynamo magnetic fields. This idea is supported by asteroseismic evidence of strong magnetic fields buried within the interiors of red giant branch stars. Assuming that these fields are disrupted by subsequent convective zones, we have estimated magnetic breakout times for WDs. Due to the significant uncertainties in breakout times stemming from the treatment of convective boundaries and mass loss rates, we cannot provide a precise prediction for the emergence time of the main-sequence dynamo field. However, we can predict that this emergence should occur during the WD phase for WDs with masses $\gtrsim 0.65 M_\odot$. We also find that the magnetic breakout is expected to occur earlier in more massive WDs, consistently with observations from volume-limited samples and the well-established fact that magnetic WDs tend to be more massive than non-magnetic ones. Moreover, within the uncertainties of stellar evolutionary models, we find that the emergence of main-sequence dynamo magnetic fields can account for a significant portion of the magnetic WDs., Comment: accepted for publication in A&A letters
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- 2024
9. Topological QBits in Flux-Quantized Super-Gravity
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Sati, Hisham and Schreiber, Urs
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High Energy Physics - Theory ,Mathematical Physics ,Mathematics - Algebraic Topology ,Quantum Physics - Abstract
We first give a brief exposition of our recent realization of anyonic quantum states on single M5-brane probes in 11D super-gravity backgrounds, by non-perturbative quantization of the topological sector of the self-dual tensor field on the 6D worldvolume, after its proper flux-quantization. This opens the prospect of holographic models for topological qbits away from the usual but unrealistic limit of large numbers of branes. At the same time, the elementary homotopy-theoretic nature of the construction yields a slick expression of topological quantum gates in homotopically-typed programming languages, opening the prospect of topological-hardware aware quantum programming. In view of these results, we end with some more meta-physical remarks on (cohesive) homotopy (type) theory in view of emergent fundamental physics and, possibly, M-theory., Comment: 16 pages, some figures -- invited contribution to: Arsiwalla, Elshatlawy & Rickles (eds.) "Quantum Gravity and Computation"
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- 2024
10. Knowledge Graph Based Visual Search Application
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Betz, Pawandeep Kaur, Hecking, Tobias, Schreiber, Andreas, and Gerndt, Andreas
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Computer Science - Databases - Abstract
The FAIR data principles advocate for making scientific and research datasets 'Findable' and 'Accessible'. Yet, the sheer volume and diversity of these datasets present significant challenges. Despite advancements in data search technologies, techniques for representing search results are still traditional and inadequate, often returning extraneous results. To address these issues, we developed a knowledge graph based visual search application designed to enhance data search for Earth System Scientists. This application utilizes various chart widgets and a knowledge graph at the backend, connecting two disparate data repositories.
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- 2024
11. Industrially fabricated single-electron quantum dots in Si/Si-Ge heterostructures
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Huckemann, Till, Muster, Pascal, Langheinrich, Wolfram, Brackmann, Varvara, Friedrich, Michael, Komerički, Nikola D., Diebel, Laura K., Stieß, Verena, Bougeard, Dominique, Dahl, Claus, Schreiber, Lars R., and Bluhm, Hendrik
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Condensed Matter - Mesoscale and Nanoscale Physics ,Quantum Physics - Abstract
This paper reports the compatibility of heterostructure-based spin qubit devices with industrial CMOS technology. It features Si/Si-Ge quantum dot devices fabricated using Infineon's 200 mm production line within a restricted thermal budget. The devices exhibit state-of-the-art charge sensing, charge noise and valley splitting characteristics, showing that industrial fabrication is not harming the heterostructure quality. These measured parameters are all correlated to spin qubit coherence and qubit gate fidelity. We describe the single electron device layout, design and its fabrication process using electron beam lithography. The incorporated standard 90 nm back-end of line flow for gate-layer independent contacting and wiring can be scaled up to multiple wiring layers for scalable quantum computing architectures. In addition, we present millikelvin characterization results. Our work exemplifies the potential of industrial fabrication methods to harness the inherent CMOS-compatibility of the Si/Si-Ge material system, despite being restricted to a reduced thermal budget. It paves the way for advanced quantum processor architectures with high yield and device quality., Comment: This work has been submitted to the IEEE for possible publication. 4 pages, 3 figures
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- 2024
12. Deep kiloparsec view of the molecular gas in a massive star-forming galaxy at cosmic noon
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Arriagada-Neira, Sebastián, Herrera-Camus, Rodrigo, Villanueva, Vicente, Schreiber, Natascha M. Förster, Lee, Minju, Bolatto, Alberto, Chen, Jianhang, Genzel, Reinhard, Liu, Daizhong, Renzini, Alvio, Tacconi, Linda J., Tozzi, Giulia, and Übler, Hannah
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Astrophysics - Astrophysics of Galaxies - Abstract
We present deep ($\sim$ 20 hr), high-angular resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations of the $\rm CO ~ (4-3)$ and $\rm [CI] ~ (1-0)$ transitions, along with the rest-frame 630 $\mu$m dust continuum, in BX610 --a massive, main-sequence galaxy at the peak epoch of cosmic star formation $(z = 2.21)$. Combined with deep Very Large Telescope (VLT) SINFONI observations of the H$\alpha$ line, we characterize the molecular gas and star formation activity on kiloparsec scales. Our analysis reveals that the excitation of the molecular gas, as traced by the $L'_{\rm CO ~ (4-3)} / L'_{\rm [CI] ~ (1-0)}$ line luminosity ratio, decreases with increasing galactocentric radius. While the line luminosity ratios in the outskirts are similar to those typically found in main-sequence galaxies at $z \sim 1$, the ratios in the central regions of BX610 are comparable to those observed in local starbursts. There is also a giant extra-nuclear star-forming clump in the southwest of BX610 that exhibits high star formation activity, molecular gas abundance, and molecular gas excitation. Furthermore, the central region of BX610 is rich in molecular gas $(M_{\rm mol} / M_{\rm \star} \approx 1)$; however, at the current level of star formation activity, such molecular gas is expected to be depleted in $\sim$ 450 Myr. This, along with recent evidence for rapid inflow toward the center, suggests that BX610 may be experiencing an evolutionary phase often referred to as wet compaction, which is expected to lead to central gas depletion and subsequent inside-out quenching of star formation activity., Comment: Submitted to Astronomy & Astrophysics. 09 pages, 05 figures
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- 2024
13. The cool brown dwarf Gliese 229 B is a close binary
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Xuan, Jerry W., Mérand, A., Thompson, W., Zhang, Y., Lacour, S., Blakely, D., Mawet, D., Oppenheimer, R., Kammerer, J., Batygin, K., Sanghi, A., Wang, J., Ruffio, J. -B., Liu, M. C., Knutson, H., Brandner, W., Burgasser, A., Rickman, E., Bowens-Rubin, R., Salama, M., Balmer, W., Blunt, S., Bourdarot, G., Caselli, P., Chauvin, G., Davies, R., Drescher, A., Eckart, A., Eisenhauer, F., Fabricius, M., Feuchtgruber, H., Finger, G., Schreiber, N. M. Förster, Garcia, P., Genzel, R., Gillessen, S., Grant, S., Hartl, M., Haußmann, F., Henning, T., Hinkley, S., Hönig, S. F., Horrobin, M., Houllé, M., Janson, M., Kervella, P., Kral, Q., Kreidberg, L., Bouquin, J. -B. Le, Lutz, D., Mang, F., Marleau, G. -D., Millour, F., More, N., Nowak, M., Ott, T., Otten, G., Paumard, T., Rabien, S., Rau, C., Ribeiro, D. C., Bordoni, M. Sadun, Sauter, J., Shangguan, J., Shimizu, T. T., Sykes, C., Soulain, A., Spezzano, S., Straubmeier, C., Stolker, T., Sturm, E., Subroweit, M., Tacconi, L. J., van Dishoeck, E. F., Vigan, A., Widmann, F., Wieprecht, E., Winterhalder, T. O., and Woillez, J.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Owing to their similarities with giant exoplanets, brown dwarf companions of stars provide insights into the fundamental processes of planet formation and evolution. From their orbits, several brown dwarf companions are found to be more massive than theoretical predictions given their luminosities and the ages of their host stars (e.g. Brandt et al. 2021, Cheetham et al. 2018, Li et al. 2023). Either the theory is incomplete or these objects are not single entities. For example, they could be two brown dwarfs each with a lower mass and intrinsic luminosity (Brandt et al. 2021, Howe et al. 2024). The most problematic example is Gliese 229 B (Nakajima et al. 1995, Oppenheimer et al. 1995), which is at least 2-6 times less luminous than model predictions given its dynamical mass of $71.4\pm0.6$ Jupiter masses ($M_{\rm Jup}$) (Brandt et al. 2021). We observed Gliese 229 B with the GRAVITY interferometer and, separately, the CRIRES+ spectrograph at the Very Large Telescope. Both sets of observations independently resolve Gliese 229 B into two components, Gliese 229 Ba and Bb, settling the conflict between theory and observations. The two objects have a flux ratio of $0.47\pm0.03$ at a wavelength of 2 $\mu$m and masses of $38.1\pm1.0$ and $34.4\pm1.5$ $M_{\rm Jup}$, respectively. They orbit each other every 12.1 days with a semimajor axis of 0.042 astronomical units (AU). The discovery of Gliese 229 BaBb, each only a few times more massive than the most massive planets, and separated by 16 times the Earth-moon distance, raises new questions about the formation and prevalence of tight binary brown dwarfs around stars., Comment: Published in Nature. The Version of Record of this article is located at https://www.nature.com/articles/s41586-024-08064-x
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- 2024
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14. Benchmark Inflation: Revealing LLM Performance Gaps Using Retro-Holdouts
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Haimes, Jacob, Wenner, Cenny, Thaman, Kunvar, Tashev, Vassil, Neo, Clement, Kran, Esben, and Schreiber, Jason
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence ,Computer Science - Computation and Language - Abstract
The training data for many Large Language Models (LLMs) is contaminated with test data. This means that public benchmarks used to assess LLMs are compromised, suggesting a performance gap between benchmark scores and actual capabilities. Ideally, a private holdout set could be used to accurately verify scores. Unfortunately, such datasets do not exist for most benchmarks, and post-hoc construction of sufficiently similar datasets is non-trivial. To address these issues, we introduce a systematic methodology for (i) retrospectively constructing a holdout dataset for a target dataset, (ii) demonstrating the statistical indistinguishability of this retro-holdout dataset, and (iii) comparing LLMs on the two datasets to quantify the performance gap due to the dataset's public availability. Applying these methods to TruthfulQA, we construct and release Retro-Misconceptions, on which we evaluate twenty LLMs and find that some have inflated scores by as much as 16 percentage points. Our results demonstrate that public benchmark scores do not always accurately assess model properties, and underscore the importance of improved data practices in the field.
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- 2024
15. Coherent X-rays reveal anomalous molecular diffusion and cage effects in crowded protein solutions
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Girelli, Anita, Bin, Maddalena, Filianina, Mariia, Dargasz, Michelle, Anthuparambil, Nimmi Das, Möller, Johannes, Zozulya, Alexey, Andronis, Iason, Timmermann, Sonja, Berkowicz, Sharon, Retzbach, Sebastian, Reiser, Mario, Raza, Agha Mohammad, Kowalski, Marvin, Akhundzadeh, Mohammad Sayed, Schrage, Jenny, Woo, Chang Hee, Senft, Maximilian D., Reichart, Lara Franziska, Leonau, Aliaksandr, Rajaiah, Prince Prabhu, Chèvremont, William, Seydel, Tilo, Hallmann, Jörg, Rodriguez-Fernandez, Angel, Pudell, Jan-Etienne, Brausse, Felix, Boesenberg, Ulrike, Wrigley, James, Youssef, Mohamed, Lu, Wei, Jo, Wonhyuk, Shayduk, Roman, Madsen, Anders, Lehmkühler, Felix, Paulus, Michael, Zhang, Fajun, Schreiber, Frank, Gutt, Christian, and Perakis, Fivos
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Condensed Matter - Soft Condensed Matter ,Physics - Chemical Physics - Abstract
Understanding protein motion within the cell is crucial for predicting reaction rates and macromolecular transport in the cytoplasm. A key question is how crowded environments affect protein dynamics through hydrodynamic and direct interactions at molecular length scales. Using megahertz X-ray Photon Correlation Spectroscopy (MHz-XPCS) at the European X-ray Free Electron Laser (EuXFEL), we investigate ferritin diffusion at microsecond time scales. Our results reveal anomalous diffusion, indicated by the non-exponential decay of the intensity autocorrelation function $g_2(q,t)$ at high concentrations. This behavior is consistent with the presence of cage-trapping in between the short- and long-time protein diffusion regimes. Modeling with the $\delta\gamma$-theory of hydrodynamically interacting colloidal spheres successfully reproduces the experimental data by including a scaling factor linked to the protein direct interactions. These findings offer new insights into the complex molecular motion in crowded protein solutions, with potential applications for optimizing ferritin-based drug delivery, where protein diffusion is the rate-limiting step.
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- 2024
16. Catastrophic Cyber Capabilities Benchmark (3CB): Robustly Evaluating LLM Agent Cyber Offense Capabilities
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Anurin, Andrey, Ng, Jonathan, Schaffer, Kibo, Schreiber, Jason, and Kran, Esben
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Computer Science - Cryptography and Security ,Computer Science - Artificial Intelligence ,Computer Science - Machine Learning ,Computer Science - Performance - Abstract
LLM agents have the potential to revolutionize defensive cyber operations, but their offensive capabilities are not yet fully understood. To prepare for emerging threats, model developers and governments are evaluating the cyber capabilities of foundation models. However, these assessments often lack transparency and a comprehensive focus on offensive capabilities. In response, we introduce the Catastrophic Cyber Capabilities Benchmark (3CB), a novel framework designed to rigorously assess the real-world offensive capabilities of LLM agents. Our evaluation of modern LLMs on 3CB reveals that frontier models, such as GPT-4o and Claude 3.5 Sonnet, can perform offensive tasks such as reconnaissance and exploitation across domains ranging from binary analysis to web technologies. Conversely, smaller open-source models exhibit limited offensive capabilities. Our software solution and the corresponding benchmark provides a critical tool to reduce the gap between rapidly improving capabilities and robustness of cyber offense evaluations, aiding in the safer deployment and regulation of these powerful technologies., Comment: https://cybercapabilities.org/
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- 2024
17. Most extremely low mass white dwarfs with non-degenerate companions are inner binaries of hierarchical triples
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Lagos-Vilches, Felipe, Hernandez, Mercedes, Schreiber, Matthias R., Parsons, Steven G., and Gänsicke, Boris T.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Extremely-low-mass white dwarfs (ELM WDs) with non-degenerate companions are believed to originate from solar-type main-sequence binaries undergoing stable Roche lobe overflow mass transfer when the ELM WD progenitor is at (or just past) the termination of the main-sequence. This implies that the orbital period of the binary at the onset of the first mass transfer phase must have been $\lesssim 3-5$ d. This prediction in turn suggests that most of these binaries should have tertiary companions since $\approx 90$ per cent of solar-type main-sequence binaries in that period range are inner binaries of hierarchical triples. Until recently, only precursors of this type of binaries have been observed in the form of EL CVn binaries, which are also known for having tertiary companions. Here, we present high-angular-resolution images of TYC 6992-827-1, an ELM WD with a sub-giant (SG) companion, confirming the presence of a tertiary companion. Furthermore, we show that TYC 6992-827-1, along with its sibling TYC 8394-1331-1 (whose triple companion was detected via radial velocity variations), are in fact descendants of EL CVn binaries. Both TYC 6992-827-1 and TYC 8394-1331-1 will evolve through a common envelope phase, which depending on the ejection efficiency of the envelope, might lead to a single WD or a tight double WD binary, which would likely merge into a WD within a few Gyr due to gravitational wave emission. The former triple configuration will be reduced to a wide binary composed of a WD (the merger product) and the current tertiary companion., Comment: 8 pages, 5 figures, 1 table. Accepted for publication in MNRAS
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- 2024
18. Upgrading SPHERE with the second stage AO system SAXO+: frequency-based data-driven controller for adaptive optics
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Dinis, Isaac, Wildi, François, Ségransan, Damien, Gupta, Vaibhav, Karimi, Alireza, Tallon, Michel, Bosc, Isabelle, Langlois, Maud, Loupias, Magali, Bechet, Clémentine, Thiébaut, Eric, Goulas, Charles, Ferreira, Florian, Boccaletti, Anthony, Vidal, Fabrice, Kulcsar, Caroline, Raynaud, Henri-François, Galland, Nicolas, Kasper, Markus, Milli, Julien, Mouillet, David, Schreiber, Laura, Diolaiti, Emiliano, Gratton, Raffaele, and Chauvin, Gael
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Electrical Engineering and Systems Science - Systems and Control ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
This study introduces a novel frequency-based data-driven controller for adaptive optics, using power spectral density for optimization while ensuring stability criteria. It addresses disturbance rejection, command amplitude constraints and system transfer functions through convex optimization to obtain an optimal control in an infinite input response filter form. Evaluated within the SAXO+ project, it demonstrates efficacy under diverse atmospheric conditions and operational scenarios. The proposed controller is tested in both standard and disentangled adaptive optics schemes, showcasing its adaptability and performance. Experimental validation is conducted using the COMPASS simulation tool, affirming the controller's promise for enhancing adaptive optics systems in real-world applications.
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- 2024
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19. Laser-FLASH: radiobiology at high dose, ultra-high dose-rate, single pulse laser-driven proton source
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Flacco, A., Bayart, E., Giaccaglia, C., Monzac, J., Romagnani, L., Cavallone, M., Patriarca, A., DeMarzi, L., Fouillade, C., Heinrich, S., Lamarre-Jouenne, I., Parodi, K., Rösch, T., Schreiber, J., and Tischendorf, L.
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Physics - Medical Physics ,Physics - Applied Physics ,Physics - Plasma Physics - Abstract
Laser-driven proton sources have long been developed with an eye on their potential for medical application to radiation therapy. These sources are compact, versatile, and show peculiar characteristics such as extreme instantaneous dose rates, short duration and broad energy spectrum. Typical temporal modality of laser-driven irradiation, the so-called fast-fractionation, results from the composition of multiple, temporally separated, ultra-short dose fractions. In this paper we present the use of a high-energy laser system for delivering the target dose in a single nanosecond pulse, for ultra-fast irradiation of biological samples. A transport line composed by two permanent magnet quadrupoles and a scattering system is used to improve the dose profile and to control the delivered dose-per-pulse. A single-shot dosimetry protocol for the broad-spectrum proton source using Monte Carlo simulations was developed. Doses as high as 20Gy could be delivered in a single shot, lasting less than 10ns over a 1.0cm diameter sample holder, at a dose-rate exceeding 10^9 Gy/s. Exploratory application of extreme laser-driven irradiation conditions, falling within the FLASH irradiation protocol, are presented for in vitro and in vivo irradiation. A reduction of radiation-induced oxidative stress in-vitro and radiation-induced developmental damage in vivo were observed, whereas anti-tumoral efficacy was confirmed by cell survival assay., Comment: 13 pages, 15 figures
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- 2024
20. The formation histories of massive and quiescent galaxies in the 3 < z < 4.5 Universe
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Nanayakkara, Themiya, Glazebrook, Karl, Schreiber, Corentin, Chittenden, Harry, Brammer, Gabriel, Esdaile, James, Jacobs, Colin, Kacprzak, Glenn G., Kawinwanichakij, Lalitwadee, Kimmig, Lucas C., Labbe, Ivo, Lagos, Claudia, Marchesini, Danilo, Martìnez-Marìn, M., Marsan, Z. Cemile, Oesch, Pascal A., Papovich, Casey, Remus, Rhea-Silvia, and Tran, Kim-Vy H.
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Astrophysics - Astrophysics of Galaxies - Abstract
We present the formation histories of 19 massive ($\gtrsim3\times10^{10}\text{M}_\odot$) quiescent galaxy candidates at $z\sim3.0-4.5$ observed using JWST/NIRSpec. This completes the spectroscopic confirmation of the 24 $K$-selected quiescent galaxy sample from the ZFOURGE and 3DHST surveys \citep{Schreiber2018}. Utilizing Prism $1-5\mu$m spectroscopy, we confirm that all 12 sources that eluded confirmation by ground-based spectroscopy lie at $z>3$, resulting in a spectroscopically confirmed number density of $\sim1.4\times10^{-5}\text{Mpc}^{-3}$ between $z\sim3-4$. Rest-frame $U-V$ vs $V-J$ color selections show high effectiveness in identifying quiescent galaxies, with a purity of $\sim90\%$. Our analysis shows that parametric star-formation histories (SFHs) from FAST++ and binned SFHs from Prospector on average yield consistent results, revealing diverse formation and quenching times. The oldest galaxy formed $\sim6\times10^{10}\text{M}_\odot$ by $z\sim10$ and has been quiescent for over 1 Gyr at $z\sim3.2$. We detect two galaxies with ongoing star formation and six with active galactic nuclei (AGN). We demonstrate that the choice of stellar population models, stellar libraries, wavelength range, and nebular or AGN contributions does not significantly affect the derived average SFHs of the galaxies. The assumed SFH prior, however, influences the star formation rate at early times, where spectral diagnostic power is limited. Simulated $z\sim3$ quiescent galaxies from IllustrisTNG, SHARK, and Magneticum broadly match the average SFHs of the observed sample but struggle to capture the full diversity, particularly at early stages. Our results emphasize the need for mechanisms that rapidly build stellar mass and quench star formation within the first billion years of the Universe., Comment: Submitted to ApJ. Comments welcome
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- 2024
21. The AURORA Survey: An Extraordinarily Mature, Star-forming Galaxy at $z\sim 7$
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Shapley, Alice E., Sanders, Ryan L., Topping, Michael W., Reddy, Naveen A., Pahl, Anthony J., Oesch, Pascal A., Berg, Danielle A., Bouwens, Rychard J., Brammer, Gabriel, Carnall, Adam C., Cullen, Fergus, Davé, Romeel, Dunlop, James S., Ellis, Richard S., Schreiber, N. M. Förster, Furlanetto, Steven R ., Glazebrook, Karl, Illingworth, Garth D., Jones, Tucker, Kriek, Mariska, McLeod, Derek J., McLure, Ross J., Narayanan, Desika, Pettini, Max, Schaerer, Daniel, Stark, Daniel P., Steidel, Charles C., Tang, Mengtao, Clarke, Leonardo, Donnan, Callum T., and Kehoe, Emily
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Astrophysics - Astrophysics of Galaxies - Abstract
We present the properties of a massive, large, dusty, metal-rich, star-forming galaxy at z_spec=6.73. GOODSN-100182 was observed with JWST/NIRSpec as part of the AURORA survey, and is also covered by public multi-wavelength HST and JWST imaging. While the large mass of GOODSN-100182 (~10^10 M_sun) was indicated prior to JWST, NIRCam rest-optical imaging now reveals the presence of an extended disk (r_eff~1.5 kpc). In addition, the NIRSpec R~1000 spectrum of GOODSN-100182 includes the detection of a large suite of rest-optical nebular emission lines ranging in wavelength from [OII]3727 up to [NII]6583. The ratios of Balmer lines suggest significant dust attenuation (E(B-V)_gas=0.40+0.10/-0.09), consistent with the red rest-UV slope inferred for GOODSN-100182 (beta=-0.50+/-0.09). The star-formation rate based on dust-corrected H-alpha emission is log(SFR(H-alpha)/ M_sun/yr)=2.02+0.13/-0.14, well above the z~7 star-forming main sequence in terms of specific SFR. Strikingly, the ratio of [NII]6583/H-alpha emission suggests almost solar metallicity, as does the ratio ([OIII]5007/H-beta)/([NII]6583/H-alpha) and the detection of the faint [FeII]4360 emission feature, whereas the [OIII]5007/[OII]3727 ratio suggests roughly 50% solar metallicity. Overall, the excitation and ionization properties of GOODSN-100182 more closely resemble those of typical star-forming galaxies at z~2-3 rather than z~7. Based on public spectroscopy of the GOODS-N field, we find that GOODSN-100182 resides within a significant galaxy overdensity, and is accompanied by a spectroscopically-confirmed neighbor galaxy. GOODSN-100182 demonstrates the existence of mature, chemically-enriched galaxies within the first billion years of cosmic time, whose properties must be explained by galaxy formation models., Comment: 16 pages, 13 figures, submitted to ApJ
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- 2024
22. The ion activated attractive patchy particles model and its application to the liquid-vapour phase transitions
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Surfaro, Furio, Zhang, Fajun, Schreiber, Frank, and Roth, Roland
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Condensed Matter - Soft Condensed Matter - Abstract
Patchy particles are an intriguing subject of study and indeed a model system in the field of soft matter physics. In recent years, patchy particle models have been applied to describe a wide variety of systems, including colloidal crystals, macromolecular interactions, liquid crystals, and nanoparticle assemblies. Given the importance of the topic, rationalizing and capturing the basic features of these models is crucial to their correct application in specific systems. In this study, we extend the ion-activated attractive patchy particles model previously employed to elucidate the phase behavior of protein solutions in the presence of trivalent salts. Our extension incorporates the effect of repulsion between unoccupied and occupied binding sites, depicted as patches. Furthermore, we examine the influence of model parameters on the liquid-vapor coexistence region within the phase diagram, employing numerical methods. A deeper understanding of this model will facilitate a better comprehension of the effects observed in experiments., Comment: 10 pages, 8 Figures
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- 2024
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23. Investigations on Algorithm Selection for Interval-Based Coding Methods
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Strutz, Tilo and Schreiber, Nico
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Computer Science - Information Theory ,Computer Science - Data Structures and Algorithms - Abstract
There is a class of entropy-coding methods which do not substitute symbols by code words (such as Huffman coding), but operate on intervals or ranges. This class includes three prominent members: conventional arithmetic coding, range coding, and coding based on asymmetric numeral systems. To determine the correct symbol in the decoder, each of these methods requires the comparison of a state variable with subinterval boundaries. In adaptive operation, considering varying symbol statistics, an array of interval boundaries must additionally be kept up to date. The larger the symbol alphabet, the more time-consuming both the search for the correct subinterval and the updating of interval borders become. Detailed pseudo-code is used to discuss different approaches to speed up the symbol search in the decoder and the adaptation of the array of interval borders, both depending on the chosen alphabet size. It is shown that reducing the $\mathcal{O}$-complexity does not lead to an acceleration in practical implementations if the alphabet size is too small. In adaptive compression mode, the binary indexing method proves to be superior when considering the overall processing time. Although the symbol search (in the decoder) takes longer than with other algorithms, the faster updating of the array of interval borders more than compensates for this disadvantage. A variant of the binary indexing method is proposed, which is more flexible and has a partially lower complexity than the original approach.
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- 2024
24. 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, Berdeu, Anthony, Berger, Jean-Philippe, Bourdarot, Guillaume, Brandner, Wolfgang, 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 = 0.724 +/- 0.002 mas and microlens parallax, we determine that the lens system consists of two M dwarfs with masses of M_1 = 0.258 +/- 0.008 M_sun and M_2 = 0.130 +/- 0.007 M_sun, a projected separation of r_\perp = 6.83 +/- 0.31 AU and a distance of D_L = 2.29 +/- 0.08 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: Accepted by ApJ. See the ancillary file for animation associated with Fig. 8
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- 2024
25. Improving constraints on the extended mass distribution in the Galactic Center with stellar orbits
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The GRAVITY Collaboration, Dayem, Karim Abd El, Abuter, Roberto, Aimar, Nicolas, Seoane, Pau Amaro, Amorim, Antonio, Beck, Julie, Berger, Jean Philippe, Bonnet, Henri, Bourdarot, Guillaume, Brandner, Wolfgang, Cardoso, Vitor, Dolcetta, Roberto Capuzzo, Clénet, Yann, Davies, Ric, de Zeeuw, Tim, Drescher, Antonia, Eckart, Andreas, Eisenhauer, Frank, Feuchtgruber, Helmut, Finger, Gert, Schreiber, Natascha M. Förster, Foschi, Arianna, Gao, Feng, Garcia, Paulo, Gendron, Eric, Genzel, Reinhard, Gillessen, Stefan, Hartl, Michael, Haubois, Xavier, Haussman, Frank, Heißel, Gernot, Hennig, Thomas, Hippler, Stefan, Horrobin, Matthew, Jochum, Lieselotte, Jocou, Laurent, Kaufer, Andreas, Kervella, Pierre, Lacour, Sylvestre, Lapeyrère, Vincent, Bouquin, Jean B. Le, Léna, Pierre, Lutz, Dieter, Mang, Felix, More, Nikhil, Ott, Thomas, Paumard, Thibaut, Perraut, Karine, Perrin, Guy, Pfuhl, Oliver, Rabien, Sebastien, Ribeiro, Diogo C., Bordoni, Matteo Sadun, Scheithauer, Silvia, Shangguan, Jinyi, Shimizu, Taro, Stadler, Julia, Straub, Odele, Straubmeier, Christian, Sturm, Eckhard, Tacconi, Linda J., Urso, Irene, Vincent, Frederic, Von Fellenberg, Sebastiano D., Widmann, Felix, Wieprecht, Ekkehard, Woillez, Julien, and Zhang, Fupeng
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Studying the orbital motion of stars around Sagittarius A* in the Galactic Center provides a unique opportunity to probe the gravitational potential near the supermassive black hole at the heart of our Galaxy. Interferometric data obtained with the GRAVITY instrument at the Very Large Telescope Interferometer (VLTI) since 2016 has allowed us to achieve unprecedented precision in tracking the orbits of these stars. GRAVITY data have been key to detecting the in-plane, prograde Schwarzschild precession of the orbit of the star S2, as predicted by General Relativity. By combining astrometric and spectroscopic data from multiple stars, including S2, S29, S38, and S55 - for which we have data around their time of pericenter passage with GRAVITY - we can now strengthen the significance of this detection to an approximately $10 \sigma$ confidence level. The prograde precession of S2's orbit provides valuable insights into the potential presence of an extended mass distribution surrounding Sagittarius A*, which could consist of a dynamically relaxed stellar cusp comprised of old stars and stellar remnants, along with a possible dark matter spike. Our analysis, based on two plausible density profiles - a power-law and a Plummer profile - constrains the enclosed mass within the orbit of S2 to be consistent with zero, establishing an upper limit of approximately $1200 \, M_\odot$ with a $1 \sigma$ confidence level. This significantly improves our constraints on the mass distribution in the Galactic Center. Our upper limit is very close to the expected value from numerical simulations for a stellar cusp in the Galactic Center, leaving little room for a significant enhancement of dark matter density near Sagittarius A*., Comment: Submitted to A&A on September 17, 2024
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- 2024
26. The ALMA-CRISTAL Survey: Spatially-resolved Star Formation Activity and Dust Content in 4 < z < 6 Star-forming Galaxies
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Li, Juno, Da Cunha, Elisabete, González-López, Jorge, Aravena, Manuel, De Looze, Ilse, Schreiber, N. M. Förster, Herrera-Camus, Rodrigo, Spilker, Justin, Tadaki, Ken-ichi, Barcos-Munoz, Loreto, Battisti, Andrew J., Birkin, Jack E., Bowler, Rebecca A. A., Davies, Rebecca, Díaz-Santos, Tanio, Ferrara, Andrea, Fisher, Deanne B., Hodge, Jacqueline, Ikeda, Ryota, Killi, Meghana, Lee, Lilian, Liu, Daizhong, Lutz, Dieter, Mitsuhashi, Ikki, Naab, Thorsten, Posses, Ana, Relaño, Monica, Solimano, Manuel, Übler, Hannah, van der Giessen, Stefan Anthony, and Villanueva, Vicente
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Astrophysics - Astrophysics of Galaxies - Abstract
Using a combination of HST, JWST, and ALMA data, we perform spatially resolved spectral energy distributions (SED) fitting of fourteen 4
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- 2024
27. Towards Real-Time Generation of Delay-Compensated Video Feeds for Outdoor Mobile Robot Teleoperation
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Chakraborty, Neeloy, Fang, Yixiao, Schreiber, Andre, Ji, Tianchen, Huang, Zhe, Mihigo, Aganze, Wall, Cassidy, Almana, Abdulrahman, and Driggs-Campbell, Katherine
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Computer Science - Robotics ,Computer Science - Computer Vision and Pattern Recognition - Abstract
Teleoperation is an important technology to enable supervisors to control agricultural robots remotely. However, environmental factors in dense crop rows and limitations in network infrastructure hinder the reliability of data streamed to teleoperators. These issues result in delayed and variable frame rate video feeds that often deviate significantly from the robot's actual viewpoint. We propose a modular learning-based vision pipeline to generate delay-compensated images in real-time for supervisors. Our extensive offline evaluations demonstrate that our method generates more accurate images compared to state-of-the-art approaches in our setting. Additionally, we are one of the few works to evaluate a delay-compensation method in outdoor field environments with complex terrain on data from a real robot in real-time. Additional videos are provided at https://sites.google.com/illinois.edu/comp-teleop., Comment: 8 pages, 4 figures, 3 tables
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- 2024
28. Long distance spin shuttling enabled by few-parameter velocity optimization
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David, Alessandro, Pazhedath, Akshay Menon, Schreiber, Lars R., Calarco, Tommaso, Bluhm, Hendrik, and Motzoi, Felix
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Quantum Physics ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Spin qubit shuttling via moving conveyor-mode quantum dots in Si/SiGe offers a promising route to scalable miniaturized quantum computing. Recent modeling of dephasing via valley degrees of freedom and well disorder dictate a slow shutting speed which seems to limit errors to above correction thresholds if not mitigated. We increase the precision of this prediction, showing that typical errors for 10 $\mu$m shuttling at constant speed results in O(1) error, using fast, automatically differentiable numerics and including improved disorder modeling and potential noise ranges. However, remarkably, we show that these errors can be brought to well below fault-tolerant thresholds using trajectory shaping with very simple parametrization with as few as 4 Fourier components, well within the means for experimental in-situ realization, and without the need for targeting or knowing the location of valley near degeneracies., Comment: 13 pages, 7 figures
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- 2024
29. An alternative approach to the osmotic second virial coefficient of protein solutions and its application to liquid liquid phase separation
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Surfaro, Furio, Maier, Ralph, Pastryk, Kai-Florian, Zhang, Fajun, Schreiber, Frank, and Roth, Roland
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Condensed Matter - Soft Condensed Matter ,Physics - Chemical Physics - Abstract
The osmotic second virial coefficient B2 is an important parameter to describe the interactions and phase behavior of protein solutions, including colloidal systems and macromolecular solutions. Another key parameter to describe the driving force of the nucleation of a new phase is the supersaturation, which is used in the classical nucleation theory framework and is connected with the favorable contribution in the Gibbs free energy in the bulk solution. In this article, we establish a connection between B2 calculated from small angle Xray scattering (SAXS) data and the values of B2 obtained from supersaturation measurements using thermodynamics considerations. The values of the second virial coefficient calculated employing this method agree with those determined via SAXS in the region near the liquid liquid phase separation border for human serum albumin and bovine serum albumin. The general relations adopted are shown to be useful for the estimation of the second virial coefficient B2 for globular proteins, in the proximity of the binodal biphasic coexistent region., Comment: 9 pages, 3 figures
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- 2024
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30. MAMBO -- An empirical galaxy and AGN mock catalogue for the exploitation of future surveys
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López-López, X., Bolzonella, M., Pozzetti, L., Salvato, M., Bisigello, L., Feltre, A., López, I. E., Viitanen, A., Allevato, V., Bongiorno, A., Girelli, G., Buchner, J., Charlot, S., Ricci, F., Schreiber, C., and Zamorani, G.
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Astrophysics - Astrophysics of Galaxies - Abstract
Aims. We present MAMBO, a flexible and efficient workflow to build empirical galaxy and Active Galactic Nuclei (AGN) mock catalogues that reproduce the physical and observational properties of these sources. Methods. We start from simulated dark matter (DM) haloes, to preserve the link with the cosmic web, and we populate them with galaxies and AGN using abundance matching techniques. We follow an empirical methodology, using stellar mass functions (SMF), host galaxy AGN mass functions and AGN accretion rate distribution functions studied at different redshifts to assign, among other properties, stellar masses, the fraction of quenched galaxies, or the AGN activity (demography, obscuration, multiwavelength emission, etc.). Results. As a proof test, we apply the method to a Millennium DM lightcone of 3.14 $\rm deg^2$ up to redshift $z=10$ and down to stellar masses $\mathcal{M} \gtrsim 10^{7.5} \, M_\odot$. We show that the AGN population from the mock lightcone here presented reproduces with good accuracy various observables, such as state-of-the-art luminosity functions in the X-ray up to $z \sim 7$ and in the ultraviolet up to $z \sim 5$, optical/NIR colour-colour diagrams, and narrow emission line diagnostic diagrams. Finally, we demonstrate how this catalogue can be used to make useful predictions for large surveys. Using \textit{Euclid} as a case example, we compute, among other forecasts, the expected surface densities of galaxies and AGN detectable in the \textit{Euclid} $H_{\rm E}$ band. We find that \textit{Euclid} might observe (on $H_{\rm E}$ only) about $10^{7}$ and $8 \times 10^{7}$ Type 1 and 2 AGN respectively, and $2 \times 10^{9}$ galaxies at the end of its 14 679 $\rm deg^2$ Wide survey, in good agreement with other published forecasts., Comment: 22 pages, 18 figures. Accepted for publication in A&A
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- 2024
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31. Suggested magnetic braking prescription derived from field complexity fails to reproduce the cataclysmic variable orbital period gap
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Ortúzar-Garzón, Valentina, Schreiber, Matthias R., and Belloni, Diogo
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Magnetic wind braking drives the spin-down of low-mass stars and the evolution of most interacting binary stars. A magnetic braking prescription that was claimed to reproduce both the period distribution of cataclysmic variables (CVs) and the evolution of the rotation rates of low-mass stars is based on a relation between the angular momentum loss rate and magnetic field complexity. The magnetic braking model based on field complexity has been claimed to predict a detached phase that could explain the observed period gap in the period distribution of CVs but has never been tested in detailed models of CV evolution. Here we fill this gap. We incorporated the suggested magnetic braking law in MESA and simulated the evolution of CVs for different initial stellar masses and initial orbital periods. We find that the prescription for magnetic braking based on field complexity fails to reproduce observations of CVs. The predicted secondary star radii are smaller than measured, and an extended detached phase that is required to explain the observed period gap (a dearth of non-magnetic CVs with periods between ${\sim}2$ and ${\sim}3$ hours) is not predicted. Proposed magnetic braking prescriptions based on a relation between the angular momentum loss rate and field complexity are too weak to reproduce the bloating of donor stars in CVs derived from observations and, in contrast to previous claims, do not provide an explanation for the observed period gap. The suggested steep decrease in the angular momentum loss rate does not lead to detachment. Stronger magnetic braking prescriptions and a discontinuity at the fully convective boundary are needed to explain the evolution of close binary stars that contain compact objects. The tension between braking laws derived from the spin-down of single stars and those required to explain CVs and other close binaries containing compact objects remains., Comment: 5 pages, 4 figures
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- 2024
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32. GraphTrials: Visual Proofs of Graph Properties
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Förster, Henry, Klesen, Felix, Dwyer, Tim, Eades, Peter, Hong, Seok-Hee, Kobourov, Stephen G., Liotta, Giuseppe, Misue, Kazuo, Montecchiani, Fabrizio, Pastukhov, Alexander, and Schreiber, Falk
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Computer Science - Human-Computer Interaction - Abstract
Graph and network visualization supports exploration, analysis and communication of relational data arising in many domains: from biological and social networks, to transportation and powergrid systems. With the arrival of AI-based question-answering tools, issues of trustworthiness and explainability of generated answers motivate a greater role for visualization. In the context of graphs, we see the need for visualizations that can convince a critical audience that an assertion about the graph under analysis is valid. The requirements for such representations that convey precisely one specific graph property are quite different from standard network visualization criteria which optimize general aesthetics and readability. In this paper, we aim to provide a comprehensive introduction to visual proofs of graph properties and a foundation for further research in the area. We present a framework that defines what it means to visually prove a graph property. In the process, we introduce the notion of a visual certificate, that is, a specialized faithful graph visualization that leverages the viewer's perception, in particular, pre-attentive processing (e.g. via pop-out effects), to verify a given assertion about the represented graph. We also discuss the relationships between visual complexity, cognitive load and complexity theory, and propose a classification based on visual proof complexity. Finally, we provide examples of visual certificates for problems in different visual proof complexity classes., Comment: Appears in the Proceedings of the 32nd International Symposium on Graph Drawing and Network Visualization (GD 2024)
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- 2024
33. South African Private Universities: The Unique Challenges of Private University First-Generation Students -- The Unique Opportunity for Private Higher Education Institutions
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Linda Meyer and Birgit Schreiber
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This article delves into the formidable obstacles first-generation students (FGS) encounter within the South African private higher education sector which locates the study on which it is based in the literature around the overall experience of first-generation students. Extensive research has underscored the various challenges faced by FGS, posing hindrances to their academic success in higher education. FGS often grapple with a complex journey fraught with challenges around finances, social adjustment, and epistemological access, to name a few. This research adopts a quantitative approach with a cross-sectional research design. The study utilises a 5-point Likert scale questionnaire supplemented by open-ended questions to gather data from a sample of 1 208 students. The study reveals that close to one-third (30.5%) of the sample found the academic requirements challenging, just less than two-thirds (63.6%) found the coursework overwhelming, and more than half (57.7%) received support from faculty and academic advisors. In terms of financial challenges, less than a quarter (21%) indicated that they face financial challenges most of the time. The results of this study are reflective of similar research on the challenges experienced by South African FGS. The authors suggest that more research is needed to examine the unique challenges the FGS experience at private universities in South Africa. Moreover, the authors argue that an overall systemic and structural transformation is needed to enable institutional changes that would ease the challenges of all students.
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- 2024
34. Student Affairs and Services: The Global South Leading the Global North in the Adoption of the Sustainable Development Goals
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Birgit Schreiber, Brett Perozzi, Lisa Bardill Moscaritolo, and Thierry Luescher
- Abstract
The United Nations Sustainable Development Goals (SDGs) are a worldwide commitment to a set of ambitious goals that advance sustainable social justice across the globe. Higher education (HE), while featuring in SDG 4: Quality Education, needs to occupy a bolder and more explicit position in the formulation of the SDGs and in their attainment, not only as an instrument toward the achievement of the SDGs but also in the sociocultural consciousness of countries towards a more sustainable and socially just world. Engaging with students in HE around these issues plays a vital role. Given Student Affairs and Services' (SAS) role and position in terms of support and development of students worldwide, it is a key player in supporting HE to become a more effective instrument in advancing the SDGs and in advancing students' attitudes and commitment to SDGs. To explore how SAS can play a more impactful role in advancing the SDGs and SAS' role in and contribution to SDGs around the world, we researched SAS practitioners' awareness of and engagement with SDGs. To collect data, we used a survey with open and closed questions via snowball sampling with self-selected participants from fifty-three countries (N=318). The results of our study suggest that SAS practitioners engage with and utilize the SDGs in a variety of ways across the globe, thus contributing to the role HE plays in advancing SDGs. In exploring the patterns, it emerges that SAS in the Global South (GS) and Global North (GN) engage differently with the SDGs. According to the results of our study, SAS in the GS appears to have more awareness of, engage more deliberately with, and use the SDGs more broadly in their work with students. While there are different trends on the role SDGs play across the global HE sector, the consensus seems to be around the need to discuss and engage with the SDGs more deeply, at curricular and co-curricular levels in higher education. Our research suggests that HE and SAS can do much more to generate awareness of SDGs, particularly in the GN.
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- 2024
35. Association of emergency department characteristics with presence of recommended pediatric-specific behavioral health policies.
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Foster, Ashley, Hoffmann, Jennifer, Crady, Rachel, Hewes, Hilary, Li, Joyce, Cook, Lawrence, Duffy, Susan, Johnson, Mark, Schreiber, Merritt, and Saidinejad, Mohsen
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behavioral health ,mental health ,pediatric readiness ,pediatrics ,policy - Abstract
OBJECTIVES: In the United States, pediatric emergency department (ED) visits for behavioral health (BH) are increasing. We sought to determine ED-level characteristics associated with having recommended BH-related policies. METHODS: We conducted a retrospective serial cross-sectional study of National Pediatric Readiness Project assessments administered to US EDs in 2013 and 2021. Changes in responses related to BH items over time were examined. Multivariable logistic regression models examined ED characteristics associated with the presence of specific BH-related policies in 2021. RESULTS: Of 3554 EDs that completed assessments in 2021, 73.0% had BH-related policies, 66.5% had transfer guidelines for children with BH issues, and 38.6% had access to BH resources in a disaster. Of 2570 EDs that completed assessments in both 2013 and 2021, presence of specific BH-related policies increased from 48.6% to 72.0% and presence of appropriate transfer guidelines increased from 56.2% to 64.9%. The adjusted odd ratios (aORs) of having specific BH-related policies were lower in rural (aOR 0.73; 95% confidence interval [CI] 0.57, 0.92) and remote EDs (aOR 0.65; 95% CI 0.48, 0.88) compared to urban EDs; lower among EDs with versus without trauma center designation (aOR 0.80; 95% CI 0.67, 0.95); and higher among EDs with a nurse and physician pediatric emergency care coordinator (PECC) (aOR 1.89; 95% CI 1.54, 2.33) versus those without a PECC. CONCLUSION: Although pediatric readiness for BH conditions increased from 2013 to 2021, gaps remain, particularly among rural EDs and designated trauma centers. Having nurse and physician PECCs is a modifiable strategy to increase ED pediatric readiness pertaining to BH.
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- 2024
36. The MICADO first light imager for the ELT: overview and current Status
- Author
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Sturm, E., Davies, R., Alves, J., Clénet, Y., Kotilainen, J., Monna, A., Nicklas, H., Pott, J. -U., Tolstoy, E., Vulcani, B., Achren, J., Annadevara, S., Anwand-Heerwart, H., Arcidiacono, C., Barboza, S., Barl, L., Baudoz, P., Bender, R., Bezawada, N., Biondi, F., Bizenberger, P., Blin, A., Boné, A., Bonifacio, P., Borgo, B., Born, J. van den, Buey, T., Cao, Y., Chapron, F., Chauvin, G., Chemla, F., Cloiseau, K., Cohen, M., Collin, C., Czoske, O., Dette, J. -O., Deysenroth, M., Dijkstra, E., Dreizler, S., Dupuis, O., van Egmond, G., Eisenhauer, F., Elswijk, E., Emslander, A., Fabricius, M., Fasola, G., Ferreira, F., Schreiber, N. M. Förster, Fontana, A., Gaudemard, J., Gautherot, N., Gendron, E., Gennet, C., Genzel, R., Ghouchou, L., Gillessen, S., Gratadour, D., Grazian, A., Grupp, F., Guieu, S., Gullieuszik, M., de Haan, M., Hartke, J., Hartl, M., Haussmann, F., Helin, T., Hess, H. -J., Hofferbert, R., Huber, H., Huby, E., Huet, J. -M., Ives, D., Janssen, A., Jaufmann, P., Jilg, T., Jodlbauer, D., Jost, J., Kausch, W., Kellermann, H., Kerber, F., Kravcar, H., Kravchenko, K., Kulcsár, C., Kunkarayakti, H., Kunst, P., Kwast, S., Lang, F., Lange, J., Lapeyrere, V., Ruyet, B. Le, Leschinski, K., Locatelli, H., Massari, D., Mattila, S., Mei, S., Merlin, F., Meyer, E., Michel, C., Mohr, L., Montargès, M., Müller, F., Münch, N., Navarro, R., Neumann, U., Neumayer, N., Neumeier, L., Pedichini, F., Pflüger, A., Piazzesi, R., Pinard, L., Porras, J., Portaluri, E., Przybilla, N., Rabien, S., Raffard, J., Raggazoni, R., Ramlau, R., Ramos, J., Ramsay, S., Raynaud, H. -F., Rhode, P., Richter, A., Rix, H. -W., Rodenhuis, M., Rohloff, R. -R., Romp, R., Rousselot, P., Sabha, N., Sassolas, B., Schlichter, J., Schuil, M., Schweitzer, M., Seemann, U., Sevin, A., Simioni, M., Spallek, L., Sönmez, A., Suuronen, J., Taburet, S., Thomas, J., Tisserand, E., Vaccari, P., Valenti, E., Kleijn, G. Verdoes, Verdugo, M., Vidal, F., Wagner, R., Wegner, M., van Winden, D., Witschel, J., Zanella, A., Zeilinger, W., Ziegleder, J., and Ziegler, B.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
MICADO is a first light instrument for the Extremely Large Telescope (ELT), set to start operating later this decade. It will provide diffraction limited imaging, astrometry, high contrast imaging, and long slit spectroscopy at near-infrared wavelengths. During the initial phase operations, adaptive optics (AO) correction will be provided by its own natural guide star wavefront sensor. In its final configuration, that AO system will be retained and complemented by the laser guide star multi-conjugate adaptive optics module MORFEO (formerly known as MAORY). Among many other things, MICADO will study exoplanets, distant galaxies and stars, and investigate black holes, such as Sagittarius A* at the centre of the Milky Way. After their final design phase, most components of MICADO have moved on to the manufacturing and assembly phase. Here we summarize the final design of the instrument and provide an overview about its current manufacturing status and the timeline. Some lessons learned from the final design review process will be presented in order to help future instrumentation projects to cope with the challenges arising from the substantial differences between projects for 8-10m class telescopes (e.g. ESO-VLT) and the next generation Extremely Large Telescopes (e.g. ESO-ELT). Finally, the expected performance will be discussed in the context of the current landscape of astronomical observatories and instruments. For instance, MICADO will have similar sensitivity as the James Webb Space Telescope (JWST), but with six times the spatial resolution., Comment: Proceedings of the SPIE, Volume 13096, id. 1309611 11 pp. (2024)
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- 2024
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37. Six Ways to Implement Divisibility by Three in miniKanren
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Schreiber, Brett, Pfingsten, Brysen, and Hemann, Jason
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Computer Science - Programming Languages - Abstract
This paper explores options for implementing the relation $n \equiv 0 \ (\text{mod} \ 3)$ within miniKanren using miniKanren numbers and its arithmetic suite. We examine different approaches starting from straightforward implementations to more optimized versions. The implementations discussed include brute-force arithmetic methods, divisibility tricks, and derivation from a finite automaton. Our contributions include an in-depth look at the process of implementing a miniKanren relation and observations on benchmarking \texttt{defrel}s. This study aims to provide practical insights for miniKanren programmers on both performance and implementation techniques.
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- 2024
38. Isolation and characterization of atomically thin mica phyllosilicates
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Haley, Kristine L., Lee, Noah F., Schreiber, Vergil M., Pereira, Nicholas T., Sterbentz, Randy M., Chung, Timothy Y., and Island, Joshua O.
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Condensed Matter - Materials Science ,Physics - Applied Physics - Abstract
One of the roadblocks to employing two-dimensional (2D) materials in next generation devices is the lack of high quality insulators. Insulating layered materials with inert and atomically flat surfaces are ideal for high performance transistors and this has been exemplified with commonly used boron nitride. While the list of insulating 2D materials is limited, the earth-abundant phyllosilicates are particularly attractive candidates. Here, we investigate the properties of atomically thin biotite and muscovite, the most common and commercially important micas from the rock-forming minerals. From a group of five natural bulk samples, energy dispersive X-ray spectroscopy is used to classify exfoliated flakes into three types of biotite, including the phlogopite endmember, and two muscovites. We provide a catalog of RGB contrast values for exfoliated flakes ranging from bilayer to approximately 175 nm. Additionally, we report the complex index of refraction for all investigated materials based on micro-reflectance measurements. Our findings suggest that earth-abundant phyllosilicates could serve as scalable insulators for logic devices employing 2D materials, potentially overcoming current limitations in the field., Comment: 18 pages, 4 figures
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- 2024
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39. Abelian Anyons on Flux-Quantized M5-Branes
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Sati, Hisham and Schreiber, Urs
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High Energy Physics - Theory ,Condensed Matter - Mesoscale and Nanoscale Physics ,Mathematical Physics ,Mathematics - Algebraic Topology ,Quantum Physics - Abstract
While fractional quantum Hall systems provide the best experimental evidence yet of (abelian) anyons plausibly necessary for future fault-tolerant quantum computation, like all strongly-coupled quantum systems their physics is not deeply understood. However, generally a promising approach is to (holographically) realize such systems on branes in string/M-theory; and specifically an old argument by Hellerman & Susskind gives a sketch of fractional quantum Hall states arising via discrete light cone quantization of M5/M9-brane intersections. Here we present a rigorous derivation of abelian anyon quantum states on M5$\perp$MO9-branes ("open M5-branes") on the discrete light cone, after globally completing the traditional local field content on the M5-worldvolume via a flux-quantization law compatible with the ambient 11d supergravity, specifically taken to be in the unstable co-Homotopy cohomology ("Hypothesis H"). The main step in the proof uses a theorem of Okuyama to identify co-Homotopy moduli spaces with configuration spaces of strings with charged endpoints, and identifies their loop spaces with cobordism of framed links that, under topological light cone quantization, turn out to be identified with the regularized Wilson loops of abelian Chern-Simons theory., Comment: 22 pages
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- 2024
40. Impacts of Tempo and Mode of Environmental Fluctuations on Population Growth: Slow- and Fast-Limit Approximations of Lyapunov Exponents for Periodic and Random Environments
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Monmarché, Pierre, Schreiber, Sebastian J., and Strickler, Édouard
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Quantitative Biology - Populations and Evolution ,Mathematics - Dynamical Systems ,Mathematics - Probability ,92D25, 37H15 - Abstract
We examine to what extent the tempo and mode of environmental fluctuations matter for the growth of structured populations. The models are switching, linear ordinary differential equations $x'(t)=A(\sigma(\omega t))x(t)$ where $x(t)=(x_1(t),\dots,x_d(t))$ corresponds to the population densities in the $d$ individual states, $\sigma(t)$ is a piece-wise constant function representing the fluctuations in the environmental states $1,\dots,N$, $\omega$ is the frequency of the environmental fluctuations, and $A(1),\dots,A(n)$ are Metzler matrices. $\sigma(t)$ can either be a periodic function or correspond to a continuous-time Markov chain. Under suitable conditions, there is a Lyapunov exponent $\Lambda(\omega)$ such that $\lim_{t\to\infty} \frac{1}{t}\log\sum_i x_i(t)=\Lambda(\omega)$ for all non-negative, non-zero initial conditions $x(0)$ (with probability one in the random case). For both forms of switching, we derive analytical first-order and second-order approximations of $\Lambda(\omega)$ in the limits of slow ($\omega\to 0$) and fast ($\omega\to\infty$) environmental fluctuations. When the order of switching and the average switching times are equal, we show that the first-order approximations of $\Lambda(\omega)$ are equivalent in the slow-switching limit, but not in the fast-switching limit. We illustrate our results with applications to stage-structured and spatially-structured models. When dispersal rates are symmetric, the first order approximations suggest that population growth rates increase with the frequency of switching -- consistent with earlier work on periodic switching. In the absence of dispersal symmetry, we demonstrate that $\Lambda(\omega)$ can be non-monotonic in $\omega$. In conclusion, our results show how population growth rates depend on the tempo ($\omega$) and mode (random versus deterministic) of the environmental fluctuations.
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- 2024
41. Holographic M-Brane Super-Embeddings
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Giotopoulos, Grigorios, Sati, Hisham, and Schreiber, Urs
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High Energy Physics - Theory ,General Relativity and Quantum Cosmology ,Mathematical Physics ,Mathematics - Differential Geometry - Abstract
Over a decade before the modern formulation of AdS/CFT duality, Duff et al. had observed a candidate microscopic explanation by identifying the CFT fields with fluctuations of probe p-branes stretched out in parallel near the horizon of their own black brane incarnation. A profound way to characterize these and more general probe p-brane configurations, especially for M5-branes, is expected to be as "super-embeddings" of their super-worldvolumes into target super-spacetime - but no concrete example of these had appeared in the literature. Here we fill this gap by constructing the explicit holographic super-embedding of probe M5-branes and M2-branes into their corresponding super-AdS backgrounds. The result seems to be novel and shows that the holographic M-probes, static with respect to the Poincar\'e chart, must sit exactly at the throat radius., Comment: 28 pages
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- 2024
42. The AURORA Survey: The Nebular Attenuation Curve of a Galaxy at z=4.41 from Ultraviolet to Near-Infrared Wavelengths
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Sanders, Ryan L., Shapley, Alice E., Topping, Michael W., Reddy, Naveen A., Berg, Danielle A., Bouwens, Rychard J., Brammer, Gabriel, Carnall, Adam C., Cullen, Fergus, Davé, Romeel, Dunlop, James S., Ellis, Richard S., Schreiber, N. M. Förster, Furlanetto, Steven R., Glazebrook, Karl, Illingworth, Garth D., Jones, Tucker, Kriek, Mariska, McLeod, Derek J., McLure, Ross J., Narayanan, Desika, Oesch, Pascal A., Pahl, Anthony J., Pettini, Max, Schaerer, Daniel, Stark, Daniel P., Steidel, Charles C., Tang, Mengtao, Clarke, Leonardo, Donnan, Callum T., and Kehoe, Emily
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Astrophysics - Astrophysics of Galaxies - Abstract
We use JWST/NIRSpec observations from the Assembly of Ultradeep Rest-optical Observations Revealing Astrophysics (AURORA) survey to constrain the shape of the nebular attenuation curve of a star-forming galaxy at z=4.41, GOODSN-17940. We utilize 11 unblended HI recombination lines to derive the attenuation curve spanning optical to near-infrared wavelengths (3751-9550 \r{A}). We then leverage a high-S/N spectroscopic detection of the rest-frame ultraviolet continuum in combination with rest-UV photometric measurements to constrain the shape of the curve at ultraviolet wavelengths. While this UV constraint is predominantly based on stellar emission, the large measured equivalent widths of H$\alpha$ and H$\beta$ indicate that GOODSN-17940 is dominated by an extremely young stellar population <10 Myr in age such that the UV stellar continuum experiences the same attenuation as the nebular emission. The resulting combined nebular attenuation curve spans 1400-9550 \r{A} and has a shape that deviates significantly from commonly assumed dust curves in high-redshift studies. Relative to the Milky Way, SMC, and Calzetti curves, the new curve has a steeper slope at long wavelengths ($\lambda>5000$ \r{A}) while displaying a similar slope across blue-optical wavelengths ($\lambda=3750-5000$ \r{A}). In the ultraviolet, the new curve is shallower than the SMC and Calzetti curves and displays no significant 2175 \r{A} bump. This work demonstrates that the most commonly assumed dust curves are not appropriate for all high-redshift galaxies. These results highlight the ability to derive nebular attenuation curves for individual high-redshift sources with deep JWST/NIRSpec spectroscopy, thereby improving the accuracy of physical properties inferred from nebular emission lines., Comment: 21 pages, 6 figures, 1 table, submitted to ApJ
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- 2024
43. The UNCOVER Survey: First Release of Ultradeep JWST/NIRSpec PRISM spectra for ~700 galaxies from z~0.3-13 in Abell 2744
- Author
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Price, Sedona H., Bezanson, Rachel, Labbe, Ivo, Furtak, Lukas J., de Graaff, Anna, Greene, Jenny E., Kokorev, Vasily, Setton, David J., Suess, Katherine A., Brammer, Gabriel, Cutler, Sam E., Leja, Joel, Pan, Richard, Wang, Bingjie, Weaver, John R., Whitaker, Katherine E., Atek, Hakim, Burgasser, Adam J., Chemerynska, Iryna, Dayal, Pratika, Feldmann, Robert, Schreiber, Natascha M. Förster, Fudamoto, Yoshinobu, Fujimoto, Seiji, Glazebrook, Karl, Goulding, Andy D., Khullar, Gourav, Kriek, Mariska, Marchesini, Danilo, Maseda, Michael V., Miller, Tim B., Muzzin, Adam, Nanayakkara, Themiya, Nelson, Erica, Oesch, Pascal A., Shipley, Heath, Smit, Renske, Taylor, Edward N., van Dokkum, Pieter, Williams, Christina C., and Zitrin, Adi
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
We present the design and observations of low resolution JWST/NIRSpec PRISM spectroscopy from the Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) Cycle 1 JWST Treasury program. Targets are selected using JWST/NIRCam photometry from UNCOVER and other programs, and cover a wide range of categories and redshifts to ensure the legacy value of the survey. These categories include the first galaxies at $z\gtrsim10$, faint galaxies during the Epoch of Reionization ($z\sim6-8$), high redshift AGN ($z\gtrsim6$), Population III star candidates, distant quiescent and dusty galaxies ($1\lesssim z \lesssim 6$), and filler galaxies sampling redshift--color--magnitude space from $z\sim 0.1-13$. Seven NIRSpec MSA masks across the extended Abell 2744 cluster were observed, along with NIRCam parallel imaging in 8 filters (F090W, F115W, F150W, F200W, F277W, F356W, F410M, F444W, F480M) over a total area of ~26 arcmin$^2$, overlapping existing HST coverage from programs including the Hubble Frontier Fields and BUFFALO. We successfully observed 553 objects down to $m_{\mathrm{F444W}}\sim30\mathrm{AB}$, and by leveraging mask overlaps, we reach total on-target exposure times ranging from 2.4-16.7h. We demonstrate the success rate and distribution of confirmed redshifts, and also highlight the rich information revealed by these ultradeep spectra for a subset of our targets. An updated lens model of Abell 2744 is also presented, including 14 additional spectroscopic redshifts and finding a total cluster mass of $M_{\mathrm{SL}}=(2.1\pm0.3)\times10^{15}\,\mathrm{M}_{\odot}$. We publicly release reduced 1D and 2D spectra for all objects observed in Summer 2023 along with a spectroscopic redshift catalog and the updated lens model of the cluster (https://jwst-uncover.github.io/DR4.html)., Comment: 19 pages, 9 figures, 4 tables, submitted to ApJ, comments welcome! Data available at: https://jwst-uncover.github.io/DR4.html (v2: figure format correction)
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- 2024
44. The ALMA-CRISTAL Survey: Spatial extent of [CII] line emission in star-forming galaxies at $z=4-6$
- Author
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Ikeda, Ryota, Tadaki, Ken-ichi, Mitsuhashi, Ikki, Aravena, Manuel, De Looze, Ilse, Schreiber, Natascha M. Förster, González-López, Jorge, Herrera-Camus, Rodrigo, Spilker, Justin, Barcos-Muñoz, Loreto, da Cunha, Elisabete, Davies, Rebecca, Díaz-Santos, Tanio, Ferrara, Andrea, Killi, Meghana, Lee, Lilian L., Li, Juno, Lutz, Dieter, Smit, Renske, Solimano, Manuel, Telikova, Kseniia, Übler, Hannah, Veilleux, Sylvain, and Villanueva, Vicente
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
We investigate the spatial extent of the [CII] line emission in a sample of 34 galaxies at $z=4-6$ from the ALMA-CRISTAL Survey. By modeling the [CII] line emission in the visibility data directly, we derive the effective radius of [CII] line emission assuming exponential distribution. These measurements comprise not only isolated galaxies but also interacting systems, identified thanks to the high spatial resolution of the data. The [CII] line radius ranges from 0.5 to 3.5 kpc with an average value of 1.9 kpc. We compare the [CII] sizes with the sizes of UV and FIR continua, which were measured from the HST F160W and ALMA Band-7 continuum images, respectively. We confirm that the [CII] line emission is more spatially extended than the continuum emission, with average size ratios of $R_{e,[CII]}/R_{e,UV}=2.90$ and $R_{e,[CII]}/R_{e,FIR}=1.54$, although about half of the FIR-detected sample show comparable spatial extent between [CII] line and FIR continuum emission ($R_{e,[CII]}\approx R_{e, FIR}$). The residual visibility data of the best-fit model do not show evidence of flux excesses either individually or in stacking analysis. This indicates that the [CII] line emission in star-forming galaxies can be characterized by an extended exponential disk profile. Overall, our results suggest that the spatial extent of [CII] line emission can primarily be explained by photodissociation regions associated with star formation activity, while the contribution from diffuse neutral medium (atomic gas) and the effects of mergers may further expand the [CII] line distributions, causing their variations among our sample. We report the correlations between the [CII] line, dust, and Lya line properties, which may be in line with our scenario. Future 3D-analysis of Lya and Ha lines will shed light on the association of the extended [CII] line emission with atomic gas and outflows., Comment: Submitted to A&A, 21 pages, 14 figures, 4 tables
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- 2024
45. The GRAVITY young stellar object survey XIV : Investigating the magnetospheric accretion-ejection processes in S CrA N
- Author
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GRAVITY Collaboration, Nowacki, H., Perraut, K., Labadie, L., Bouvier, J., Dougados, C., Benisty, M., Wojtczak, J. A., Soulain, A., Alecian, E., Brandner, W., Garatti, A. Caratti o, Lopez, R. Garcia, Ganci, V., Sánchez-Bermúdez, J., Berger, J. -P., Bourdarot, G., Caselli, P., Clénet, Y., Davies, R., Drescher, A., Eckart, A., Eisenhauer, F., Fabricius, M., Feuchtgruber, H., Förster-Schreiber, N. M., Garcia, P., Gendron, E., Genzel, R., Gillessen, S., Grant, S., Henning, T., Jocou, L., Kervella, P., Kurtovic, N., Lacour, S., Lapeyrère, V., Bouquin, J. -B. Le, Lutz, D., Mang, F., Ott, T., Paumard, T., Perrin, G., Rabien, S., Ribeiro, D., Bordoni, M. Sadun, Scheithauer, S., Shangguan, J., Shimizu, T., Spezzano, S., Straubmeier, C., Sturm, E., Tacconi, L., van Dishoeck, E., Vincent, F., and Widmann, F.
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
The dust- and gas-rich protoplanetary disks around young stellar systems play a key role in star and planet formation. While considerable progress has recently been made in probing these disks on large scales of a few tens of astronomical units (au), the central au needs to be more investigated. We aim at unveiling the physical processes at play in the innermost regions of the strongly accreting T Tauri Star S CrA N by means of near-infrared interferometric observations. The K-band continuum emission is well reproduced with an azimuthally-modulated dusty ring. As the star alone cannot explain the size of this sublimation front, we propose that magnetospheric accretion is an important dust-heating mechanism leading to this continuum emission. The differential analysis of the Hydrogen Br$\gamma$ line is in agreement with radiative transfer models combining magnetospheric accretion and disk winds. Our observations support an origin of the Br$\gamma$ line from a combination of (variable) accretion-ejection processes in the inner disk region.
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- 2024
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46. Self-centering 3-DoF feet controller for hands-free locomotion control in telepresence and virtual reality
- Author
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Memmesheimer, Raphael, Lenz, Christian, Schwarz, Max, Schreiber, Michael, and Behnke, Sven
- Subjects
Computer Science - Robotics ,Computer Science - Human-Computer Interaction - Abstract
We present a novel seated feet controller for handling 3-DoF aimed to control locomotion for telepresence robotics and virtual reality environments. Tilting the feet on two axes yields in forward, backward and sideways motion. In addition, a separate rotary joint allows for rotation around the vertical axis. Attached springs on all joints self-center the controller. The HTC Vive tracker is used to translate the trackers' orientation into locomotion commands. The proposed self-centering feet controller was used successfully for the ANA Avatar XPRIZE competition, where a naive operator traversed the robot through a longer distance, surpassing obstacles while solving various interaction and manipulation tasks in between. We publicly provide the models of the mostly 3D-printed feet controller for reproduction., Comment: 4 pages, 7 figures, submitted to 2024 IEEE International Conference on Telepresence (Tele 2024)
- Published
- 2024
47. Lyrics Transcription for Humans: A Readability-Aware Benchmark
- Author
-
Cífka, Ondřej, Schreiber, Hendrik, Miner, Luke, and Stöter, Fabian-Robert
- Subjects
Electrical Engineering and Systems Science - Audio and Speech Processing ,Computer Science - Computation and Language ,Computer Science - Machine Learning ,Computer Science - Sound - Abstract
Writing down lyrics for human consumption involves not only accurately capturing word sequences, but also incorporating punctuation and formatting for clarity and to convey contextual information. This includes song structure, emotional emphasis, and contrast between lead and background vocals. While automatic lyrics transcription (ALT) systems have advanced beyond producing unstructured strings of words and are able to draw on wider context, ALT benchmarks have not kept pace and continue to focus exclusively on words. To address this gap, we introduce Jam-ALT, a comprehensive lyrics transcription benchmark. The benchmark features a complete revision of the JamendoLyrics dataset, in adherence to industry standards for lyrics transcription and formatting, along with evaluation metrics designed to capture and assess the lyric-specific nuances, laying the foundation for improving the readability of lyrics. We apply the benchmark to recent transcription systems and present additional error analysis, as well as an experimental comparison with a classical music dataset., Comment: ISMIR 2024 camera-ready. 6 pages + references + supplementary material. Website https://audioshake.github.io/jam-alt/ Data https://huggingface.co/datasets/audioshake/jam-alt Code https://github.com/audioshake/alt-eval/. arXiv admin note: text overlap with arXiv:2311.13987
- Published
- 2024
48. Fast and Reliable Probabilistic Reflectometry Inversion with Prior-Amortized Neural Posterior Estimation
- Author
-
Starostin, Vladimir, Dax, Maximilian, Gerlach, Alexander, Hinderhofer, Alexander, Tejero-Cantero, Álvaro, and Schreiber, Frank
- Subjects
Physics - Applied Physics ,Condensed Matter - Soft Condensed Matter ,Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
Reconstructing the structure of thin films and multilayers from measurements of scattered X-rays or neutrons is key to progress in physics, chemistry, and biology. However, finding all structures compatible with reflectometry data is computationally prohibitive for standard algorithms, which typically results in unreliable analysis with only a single potential solution identified. We address this lack of reliability with a probabilistic deep learning method that identifies all realistic structures in seconds, setting new standards in reflectometry. Our method, Prior-Amortized Neural Posterior Estimation (PANPE), combines simulation-based inference with novel adaptive priors that inform the inference network about known structural properties and controllable experimental conditions. PANPE networks support key scenarios such as high-throughput sample characterization, real-time monitoring of evolving structures, or the co-refinement of several experimental data sets, and can be adapted to provide fast, reliable, and flexible inference across many other inverse problems.
- Published
- 2024
49. Optimizing ToF-SIMS Depth Profiles of Semiconductor Heterostructures
- Author
-
Tröger, Jan, Kersting, Reinhard, Hagenhoff, Birgit, Bougeard, Dominique, Abrosimov, Nikolay V., Klos, Jan, Schreiber, Lars R., and Bracht, Hartmut
- Subjects
Physics - Applied Physics ,Condensed Matter - Materials Science - Abstract
The continuous technological development of electronic devices and the introduction of new materials leads to ever greater demands on the fabrication of semiconductor heterostructures and their characterization. This work focuses on optimizing Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) depth profiles of semiconductor heterostructures aiming at a minimization of measurement-induced profile broadening. As model system, a state-of-the-art Molecular Beam Epitaxy (MBE) grown multilayer homostructure consisting of $^{\textit{nat}}$Si/$^{28}$Si bilayers with only 2 nm in thickness is investigated while varying the most relevant sputter parameters. Atomic concentration-depth profiles are determined and an error function based description model is used to quantify layer thicknesses as well as profile broadening. The optimization process leads to an excellent resolution of the multilayer homostructure. The results of this optimization guide to a ToF-SIMS analysis of another MBE grown heterostructure consisting of a strained and highly purified $^{28}$Si layer sandwiched between two Si$_{0.7}$Ge$_{0.3}$ layers. The sandwiched $^{28}$Si layer represents a quantum well that has proven to be an excellent host for the implementation of electron-spin qubits., Comment: 10 pages, 10 figures
- Published
- 2024
50. Open Artificial Knowledge
- Author
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Borisov, Vadim and Schreiber, Richard H.
- Subjects
Computer Science - Computation and Language ,Computer Science - Machine Learning - Abstract
The tremendous success of chat-based AI systems like ChatGPT, Claude, and Gemini stems from Large Language Models (LLMs) trained on vast amount of datasets. However, acquiring high-quality, diverse, and ethically sourced training data remains a significant challenge. We introduce the Open Artificial Knowledge (OAK) dataset, a large-scale resource of over 500 million tokens (at the moment of writing) designed to address this issue. OAK leverages an ensemble of state-of-the-art LLMs, including GPT4o, LLaMa3-70B, LLaMa3-8B, Mixtral-8x7B, Gemma-7B, and Gemma-2-9B , to generate high-quality text across diverse domains, guided by Wikipedia's main categories. Our methodology ensures broad knowledge coverage while maintaining coherence and factual accuracy. The OAK dataset aims to foster the development of more capable and aligned language models while addressing critical issues of data scarcity and privacy in LLM training, and it is freely available on www.oakdataset.org.
- Published
- 2024
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