cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
First results of the CROME experiment
Creators: name: Smida, R.
name: Bluemer, H.
name: Engel, R.
name: Haungs, A.
name: Huege, T.
name: Kampert, K. -H.
name: Klages, H.
name: Kleifges, M.
name: Kroemer, O.
name: Mathys, S.
name: Rautenberg, J.
name: Riegel, M.
name: Roth, M.
name: Salamida, F.
name: Schieler, H.
name: Stasielak, J.
name: Unger, M.
name: Weber, M.
name: Werner, F.
name: Wilczynski, H.
name: Wochele, J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: It is expected that a radio signal in the microwave range is produced in the atmosphere due to molecular bremsstrahlung initiated by extensive air showers. The CROME (Cosmic-Ray Observation via Microwave Emission) experiment was built to search for this microwave signal. Radiation from the atmosphere is monitored in the extended C band (3.4--4.2 GHz) in coincidence with showers detected by the KASCADE-Grande experiment. The detector setup consists of several parabolic antennas and fast read-out electronics. The sensitivity of the detector has been measured with different methods. First results after half a year of data taking are presented.
description: Contributions to the 32nd International Cosmic Ray Conference, Beijing, China, August 2011
Estimation of non-symmetric and unbounded region of attraction using shifted shape function and R-composition
Creators: name: Li, Dongyang
name: Ignatyev, Dmitry
name: Tsourdos, Antonios
name: Wang, Zhongyuan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: A general numerical method using sum of squares programming is proposed to address the problem of estimating the region of attraction (ROA) of an asymptotically stable equilibrium point of a nonlinear polynomial system. The method is based on Lyapunov theory, and a shape function is defined to enlarge the provable subset of a local Lyapunov function. In contrast with existing methods with a shape function centered at the equilibrium point, the proposed method utilizes a shifted shape function (SSF) with its center shifted iteratively towards the boundary of the newly obtained invariant subset to improve ROA estimation. A set of shifting centers with corresponding SSFs is generated to produce proven subsets of the exact ROA and then a composition method, namely R-composition, is employed to express these independent sets in a compact form by just a single but richer-shaped level set. The proposed method denoted as RcomSSF brings a significant improvement for general ROA estimation problems, especially for non-symmetric or unbounded ROA, while keeping the computational burden at a reasonable level. Its effectiveness and advantages are demonstrated by several benchmark examples from literature.
description: 44 pages, 9 figures, ISA Transactions, 2022
Stochastic and parameter analysis for an integrative cancer model
Creators: name: Reale, Marcela
name: Margarit, David
name: Scagliotti, Ariel
name: Romanelli, Lilia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: In a previous work, we presented a model that integrates cancer cell differentiation and immunotherapy, analysing a particular therapy against cancer stem cells by cytotoxic cell vaccines. As every biological system is exposed to random fluctuations, it is important to study its stochasticity. The influence of demographic and multiplicative noise in the system is carry out on the parameters of reproduction and death in cancer cells. On the other hand, we incorporated fluctuations by adding multiplicative noise. In both cases, we analysed the dynamics for different values of the parameters involved. The final amount of cancer cells decreases for different combinations of these parameters and noise intensity is found.
ALMA Lensing Cluster Survey: $HST$ and $Spitzer$ Photometry of 33 Lensed Fields Built with CHArGE
Creators: name: Kokorev, Vasily
name: Brammer, Gabriel
name: Fujimoto, Seiji
name: Kohno, Kotaro
name: Magdis, Georgios E.
name: Valentino, Francesco
name: Toft, Sune
name: Oesch, Pascal
name: Davidzon, Iary
name: Bauer, Franz E.
name: Coe, Dan
name: Egami, Eiichi
name: Oguri, Masamune
name: Ouchi, Masami
name: Postman, Marc
name: Richard, Johan
name: Jolly, Jean-Baptiste
name: Knudsen, Kirsten K.
name: Sun, Fengwu
name: Weaver, John R.
name: Ao, Yiping
name: Baker, Andrew J.
name: Bradley, Larry
name: Caputi, Karina I.
name: Dessauges-Zavadsky, Miroslava
name: Espada, Daniel
name: Hatsukade, Bunyo
name: Koekemoer, Anton M.
name: Arancibia, Alejandra M. Muñoz
name: Shimasaku, Kazuhiro
name: Umehata, Hideki
name: Wang, Tao
name: Wang, Wei-Hao
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a set of multi-wavelength mosaics and photometric catalogs in the ALMA lensing cluster survey (ALCS) fields. The catalogs were built by reprocessing of archival data from the CHArGE compilation, taken by the $\textit{Hubble Space Telescope}$ ($\textit{HST}$) in the RELICS, CLASH and Hubble Frontier Fields. Additionally we have reconstructed the $\textit{Spitzer}$ IRAC 3.6 and 4.5 $μ$m mosaics, by utilising all the available archival IRSA/SHA exposures. To alleviate the effect of blending in such a crowded region, we have modelled the $\textit{Spitzer}$ photometry by convolving the $\textit{HST}$ detection image with the $\textit{Spitzer}$ PSF using the novel $\texttt{golfir}$ software. The final catalogs contain 218,000 sources, covering a combined area of 690 arcmin$^2$. These catalogs will serve as an important tool in aiding the search of the sub-mm galaxies in future ALMA surveys, as well as follow ups of the $\textit{HST}$ dark - IRAC sources. Coupled with the available $\textit{HST}$ photometry the addition of the 3.6 and 4.5 $μ$m bands will allow us to place a better constraint on photometric redshifts and stellar masses of these objects, thus giving us an opportunity to identify high-redshift candidates for spectroscopic follow ups and answer the important questions regarding the epoch of reionization and formation of first galaxies.
description: 41 pages, 16 figures, 8 tables. Accepted to ApJS. Mosaics and photometric catalogs can be accessed online https://github.com/dawn-cph/alcs-clusters
The Cartan geometry of the rotating Kepler problem
Creators: name: Cieliebak, Kai
name: Frauenfelder, Urs
name: van Koert, Otto
Publisher: name: arXiv
Year: 2011
Subjects: subject: Differential Geometry (math.DG)
subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics

description: We investigate the Cartan and Finsler geometry of the rotating Kepler problem, a limit case of the restricted three body problem that arises if the mass of the one of the primaries goes to zero. We show that the Hamiltonian for the rotating Kepler problem can be regarded as the Legendre transform of a certain family of Finsler metrics on the two-sphere. For very negative energy levels, these Finsler metrics are close to the round metric, and the associated flag curvature is hence positive. On the other hand, we show that the flag curvature can become negative once the energy level becomes sufficiently high.
description: 14 pages, 4 figures
Theory of fractional-Lévy kinetics for cold atoms diffusing in optical lattices
Creators: name: Kessler, David A.
name: Barkai, Eli
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Recently, anomalous superdiffusion of ultra cold 87Rb atoms in an optical lattice has been observed along with a fat-tailed, Lévy type, spatial distribution. The anomalous exponents were found to depend on the depth of the optical potential. We find, within the framework of the semiclassical theory of Sisyphus cooling, three distinct phases of the dynamics, as the optical potential depth is lowered: normal diffusion; Lévy diffusion; and x ~ t^3/2 scaling, the latter related to Obukhov's model (1959) of turbulence. The process can be formulated as a Lévy walk, with strong correlations between the length and duration of the excursions. We derive a fractional diffusion equation describing the atomic cloud, and the corresponding anomalous diffusion coefficient.
Superradiance in Stars: Non-equilibrium approach to damping of fields in stellar media
Creators: name: Chadha-Day, Francesca
name: Garbrecht, Björn
name: McDonald, Jamie
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Superradiance in black holes is well-understood but a general treatment for superradiance in stars has until now been lacking. This is surprising given the ease with which we can observe isolated neutron stars and the array of signatures which would result from stellar superradiance. In this work, we present the first systematic pipeline for computing superradiance rates in rotating stars. Our method can be used with any Lagrangian describing the interaction between the superradiant field and the constituents of the star. Our scheme falls into two parts: firstly we show how field theory at finite density can be used to express the absorption of long wavelength modes into the star in terms of microphsyical scattering processes. This allows us to derive a damped equation of motion for the bosonic field. We then feed this into an effective theory for long wavelengths (the so-called worldline formalism) to describe the amplification of superradiant modes of arbitrary multipole moment for a rapidly rotating star. Our method places stellar superradiance on a firm theoretical footing and allows the calculation of the superradiance rate arising from any interaction between a bosonic field and stellar matter.
description: Four figures, 20 pages, comments welcome
Visualisation of Manifesto - Reshaping the Academic Self: Connecting Education & Open Science
Creators: name: De Knecht, Sicco
name: Van Der Meer, Martijn
name: Brinkman, Loek
name: Kluijtmans, Manon
name: Miedema, Frank
Publisher: name: Zenodo
Year: 2021
Subjects: Open Science
Education
Reflexivity
Recognition and Rewards
Open Educational Resources

description: The transition towards Open Science will drastically alter our approach to academic life. It will change the ways in which we reward and recognise university employees and reshape the relationship between education and research. This should be reflected in how a new generation of academics and citizens are educated. Not only through the qualifications our students receive to become productive members of society, but also by dint of the values and attitudes we teach our pupils. The aim of university education should be preparing future graduates to share their (inter)disciplinary knowledge, engage with societal stakeholders, and shape tomorrow’s society. Now is the time to explore how. This is the visualization of the manifesto intended as a thought exercise to explore the (possible) relationships between Open Science and education. It attempts to point out the overlap, parallels, synergy, and possible conflicts between Open Science attitudes and practices, and contemporary views and practices in education. We aim to provoke a perspective on the different aspects of how Open Science relates to education and propose several concrete directions forward and possible corresponding interventions. After explaining why education from an Open Science perspective needs to be explored and strengthened, we differentiate four faces of open education: the Open Science mindset, Open Science skillset, open educational resources, and how these activities should be recognised and rewarded. We subsequently illuminate three possible paths on how to strengthen open education, ranging from content to form and system. We hope that this will spark a broader national and international conversation on the relationship between Open Science and education.
It's All in the Embedding! Fake News Detection Using Document Embeddings
Creators: name: Truică, Ciprian-Octavian
name: Apostol, Elena-Simona
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: With the current shift in the mass media landscape from journalistic rigor to social media, personalized social media is becoming the new norm. Although the digitalization progress of the media brings many advantages, it also increases the risk of spreading disinformation, misinformation, and malformation through the use of fake news. The emergence of this harmful phenomenon has managed to polarize society and manipulate public opinion on particular topics, e.g., elections, vaccinations, etc. Such information propagated on social media can distort public perceptions and generate social unrest while lacking the rigor of traditional journalism. Natural Language Processing and Machine Learning techniques are essential for developing efficient tools that can detect fake news. Models that use the context of textual data are essential for resolving the fake news detection problem, as they manage to encode linguistic features within the vector representation of words. In this paper, we propose a new approach that uses document embeddings to build multiple models that accurately label news articles as reliable or fake. We also present a benchmark on different architectures that detect fake news using binary or multi-labeled classification. We evaluated the models on five large news corpora using accuracy, precision, and recall. We obtained better results than more complex state-of-the-art Deep Neural Network models. We observe that the most important factor for obtaining high accuracy is the document encoding, not the classification model's complexity.
Portals into Higgs vacuum stability
Creators: name: Hiller, Gudrun
name: Höhne, Tim
name: Litim, Daniel F.
name: Steudtner, Tom
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We address the notorious metastability of the standard model (SM) and promote it to a model building task: What are the new ingredients required to stabilize the SM up to the Planck scale without encountering subplanckian Landau poles? Using the SM extended by vector-like fermions (VLFs), we chart out the corresponding landscape of Higgs stability. We find that the gauge portal mechanism, triggered by new SM charge carriers, opens up sizeable room for stability in a minimally invasive manner. We also find models with Higgs criticality, and Yukawa portals opening up at stronger coupling. Several models allow for VLFs in the TeV-range, which can be searched for at the LHC. For nontrivial flavor structure severe flavor-changing neutral current constraints arise which complement those from stability, and push lower fermion masses up to $\mathcal{O}(10^3\,\text{TeV})$.
description: 18 pages, 16 figures. v2: match published version
Deuteron Magnetic Quadrupole Moment From Chiral Effective Field Theory
Creators: name: Liu, C. -P.
name: de Vries, J.
name: Mereghetti, E.
name: Timmermans, R. G. E.
name: van Kolck, U.
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We calculate the magnetic quadrupole moment (MQM) of the deuteron at leading order in the systematic expansion provided by chiral effective field theory. We take into account parity and time-reversal violation which, at the quark-gluon level, results from the QCD vacuum angle and dimension-six operators that originate from physics beyond the Standard Model. We show that the deuteron MQM can be expressed in terms of five low-energy constants that appear in the parity- and time-reversal-violating nuclear potential and electromagnetic current, four of which also contribute to the electric dipole moments of light nuclei. We conclude that the deuteron MQM has an enhanced sensitivity to the QCD vacuum angle and that its measurement would be complementary to the proposed measurements of light-nuclear EDMs.
Hadron interactions in lattice QCD
Creators: name: Aoki, Sinya
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Progress on the potential method, recently proposed to investigate hadron interactions in lattice QCD, is reviewed. The strategy to extract the potential in lattice QCD is explained in detail. The method is applied to extract $NN$ potentials, hyperon potentials and the meson-baryon potentials. A theoretical investigation is made to understand the origin of the repulsive core using the operator product expansion. Some recent extensions of the method are also discussed.
description: 52 pages, 65 figures, Review to appear in "Progress in Particle and Nuclear Physics"
"The important thing is not to stop questioning", including the symmetries on which is based the Standard Model
Creators: name: Sternheimer, Daniel
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Algebra (math.QA)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 81R50, 53D55, 17B37, 53Z05, 81S10

description: New fundamental physical theories can, so far a posteriori, be seen as emerging from existing ones via some kind of deformation. That is the basis for Flato's ``deformation philosophy", of which the main paradigms are the physics revolutions from the beginning of the twentieth century, quantum mechanics (via deformation quantization) and special relativity. On the basis of these facts we describe two main directions by which symmetries of hadrons (strongly interacting elementary particles) may ``emerge" by deforming in some sense (including quantization) the Anti de Sitter symmetry (AdS), itself a deformation of the Poincare group of special relativity. The ultimate goal is to base on fundamental principles the dynamics of strong interactions, which originated half a century ago from empirically guessed ``internal" symmetries. After a rapid presentation of the physical (hadrons) and mathematical (deformation theory) contexts, we review a possible explanation of photons as composites of AdS singletons (in a way compatible with QED) and of leptons as similar composites (massified by 5 Higgs, extending the electroweak model to 3 generations). Then we present a ``model generating" multifaceted framework in which AdS would be deformed and quantized (possibly at root of unity and/or in manner not yet mathematically developed with noncommutative ``parameters"). That would give (using deformations) a space-time origin to the ``internal" symmetries of elementary particles, on which their dynamics were based, and either question, or give a conceptually solid base to, the Standard Model, in line with Einstein's quotation:``The important thing is not to stop questioning. Curiosity has its own reason for existing."
description: 31 pagws
Multilayer Graphene Synthesized by CVD Using Liquid Hexane as the Carbon Precursor
Creators: name: Bautista, C.
name: Mendoza, D.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We produce multilayer graphene by the Chemical Vapor Deposition (CVD) method at atmospheric pressure and 1000 °C, using flexible copper substrates as catalyst and liquid hexane as the source of carbon. We designed an optical device to measure the transmittance of the carbon films; with this information we calculate that the approximate number of layers is 11.
description: 6 pages, 5 figures. Accepted for publication in World Journal of Condensed Matter Physics
Self-consistent Ginzburg-Landau theory for transport currents in superconductors
Creators: name: Ogren, M.
name: Soerensen, M. P.
name: Pedersen, N. F.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We elaborate on boundary conditions for Ginzburg-Landau (GL) theory in the case of external currents. We implement a self-consistent theory within the finite element method (FEM) and present numerical results for a two-dimensional rectangular geometry. We emphasize that our approach can in principle also be used for general geometries in three-dimensional superconductors.
description: 4 pages, 2 figures, to be published in Physica C
Do Not Sleep on Traditional Machine Learning: Simple and Interpretable Techniques Are Competitive to Deep Learning for Sleep Scoring
Creators: name: Van Der Donckt, Jeroen
name: Van Der Donckt, Jonas
name: Deprost, Emiel
name: Vandenbussche, Nicolas
name: Rademaker, Michael
name: Vandewiele, Gilles
name: Van Hoecke, Sofie
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (stat.ML)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Over the last few years, research in automatic sleep scoring has mainly focused on developing increasingly complex deep learning architectures. However, recently these approaches achieved only marginal improvements, often at the expense of requiring more data and more expensive training procedures. Despite all these efforts and their satisfactory performance, automatic sleep staging solutions are not widely adopted in a clinical context yet. We argue that most deep learning solutions for sleep scoring are limited in their real-world applicability as they are hard to train, deploy, and reproduce. Moreover, these solutions lack interpretability and transparency, which are often key to increase adoption rates. In this work, we revisit the problem of sleep stage classification using classical machine learning. Results show that competitive performance can be achieved with a conventional machine learning pipeline consisting of preprocessing, feature extraction, and a simple machine learning model. In particular, we analyze the performance of a linear model and a non-linear (gradient boosting) model. Our approach surpasses state-of-the-art (that uses the same data) on two public datasets: Sleep-EDF SC-20 (MF1 0.810) and Sleep-EDF ST (MF1 0.795), while achieving competitive results on Sleep-EDF SC-78 (MF1 0.775) and MASS SS3 (MF1 0.817). We show that, for the sleep stage scoring task, the expressiveness of an engineered feature vector is on par with the internally learned representations of deep learning models. This observation opens the door to clinical adoption, as a representative feature vector allows to leverage both the interpretability and successful track record of traditional machine learning models.
description: The first two authors contributed equally. Accepted to Biomedical Signal Processing and Control
Nutational switching in ferromagnets and antiferromagnets
Creators: name: Winter, Lucas
name: Großenbach, Sebastian
name: Nowak, Ulrich
name: Rózsa, Levente
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: It was demonstrated recently that on ultrashort time scales magnetization dynamics does not only exhibit precession but also nutation. Here, we investigate how nutation can contribute to spin switching leading towards ultrafast data writing. We use analytic theory and atomistic spin simulations to discuss the behavior of ferromagnets and antiferromagnets in high-frequency magnetic fields. In ferromagnets, linearly polarized fields align the magnetization perpendicular to the external field, enabling $90^{\circ}$ switching. For circularly polarized fields in the $xy$ plane, the magnetization tilts to the $z$ direction. During this tilting, it rotates around the $z$ axis, allowing $180^{\circ}$ switching. In antiferromagnets, external fields with frequencies higher than the nutation frequency align the order parameter parallel to the field direction, while for lower frequencies it is oriented perpendicular to the field. The switching frequency increases with the magnetic field strength, and it deviates from the Larmor frequency, making it possible to outpace precessional switching in high magnetic fields.
description: 12 pages, 11 figures
hyperlearning. Prozessbegleitende Evaluation eines Weiterbildungsangebots für die Schulleitungen der Teilautonomen Volksschulen im Internet
Creators: name: Clases, Christoph
name: Manser, Tanja
name: Wehner, Theo
Publisher: name: TUHH Universitätsbibliothek
Year: 2001
Subjects: classificationCode: 81.05
subject: Bildungsforschung
classificationCode: 81.51
subject: Lernprozess
classificationCode: 81.68
subject: Computereinsatz in Unterricht und Ausbildung
classificationCode: 81.45
subject: Schulverwaltung
subject: E-Learning
subject: Berufliche Fortbildung
subject: Internet
subject: Virtuelle Hochschule
subject: Lerntechnik

description: Das von der Bildungsdirektion Zürich initiierte TaV-Projekt legt die Einrichtung von Schulleitungen in der Volksschule fest. Das Pestalozzianum, das Aus- und Weiterbildungen für diese SchulleiterInnen anbietet, will mit dem Projekt "Schulleitungen lernen vernetzt" deren Professionalisierung für den neuen Aufgabenbereich fördern. Die SchulleiterInnen sollen über das Internet in den Themenbereichen Führung und Wissensmanagement ausgebildet werden. Das Projekt orientiert sich an der Praxis und ist auf konkrete Fragen aus dem Schulleitungsalltag ausgerichtet. Das Erfahrungswissen der Beteiligten sowie der wechselseitige Austausch werden hierbei stark gewichtet. Für das Projekt Schulleitungen lernen vernetzt wurde eine Internetplattform zur Verfügung gestellt, um die zentralen Ziele der Weiterbildung – das Networking, den Innovationstransfer, den Wissensaustausch sowie die inhaltliche Schulung zum Thema Wissensmanagement – virtuell zu realisieren. Zugleich wurden in Form von vier Workshops Präsenzveranstaltungen organisiert, um in den technischen Umgang mit dem für viele TeilnehmerInnen neuen Medium einzuführen und die thematische Arbeit in Kopräsenz vorzubereiten. Die Plattform selbst bot TeilnehmerInnen Möglichkeiten der asynchronen (in Form eines strukturierten Diskussionsforums) wie synchronen Kommunikation (Chat). Andererseits wurde eine elektronische Bibliothek aufgebaut, die den Aufbau eines gemeinsam genutzten Dokumentenpools erlaubte.
Hyperfine Structure of $nP_{1/2}$ Rydberg States in $^{85}$Rb
Creators: name: Cardman, Ryan
name: Raithel, Georg
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We measure the hyperfine structure of $nP_{1/2}$ Rydberg states using mm-wave spectroscopy on an ensemble of laser-cooled $^{85}$Rb atoms. Systematic uncertainties in our measurement from the Zeeman splittings induced by stray magnetic fields and dipole-dipole interactions between two Rydberg atoms are factored in with the obtained statistical uncertainty. Our final measurement of the $nP_{1/2}$ hyperfine coupling constant is $A_{\text{hfs}}=1.443(31)$~GHz. This measurement is useful for studies of long-range Rydberg molecules, Rydberg electrometry, and quantum simulation with dipole-dipole interactions involving $nP_{1/2}$ atoms.
How Barrow Entropy Modifies Gravity: With Comments on Tsallis Entropy
Creators: name: Di Gennaro, Sofia
name: Xu, Hao
name: Ong, Yen Chin
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Barrow proposed that the area law of the horizon entropy might receive a "fractal correction" $S\propto A^{1+Δ/2}$ due to quantum gravitational effects, with $0\leqslant Δ\leqslant 1$ measures the deviation from the standard area law. While such a modification has been widely studied in the literature, its corresponding theory of gravity has not been discussed. We follow Jacobson's approach to derive the modified gravity theory (interpreted as an effective theory), and find that in the stationary case the resulting theory only differs from general relativity by a re-scaled cosmological constant. Consequently in asymptotically flat stationary spacetimes the theory is identical to general relativity. The theory is not applicable when there is no horizon; the multi-horizon case is complicated. We emphasize on the importance of identifying the correct thermodynamic mass in a theory with modified thermodynamics to avoid inconsistencies. We also comment on the Hawking evaporation rate beyond the effective theory. In addition, we show that the Bekenstein bound is satisfied if the thermodynamic mass is used as the energy, up to a constant prefactor. We briefly comment on the Tsallis entropy case as well. Interestingly, for the latter, the requirement that Bekenstein bound holds imposes a lower bound on the non-extensive parameter: $δ> 1/2$, which unfortunately rules out the previously suggested possibility that the expansion of the universe can accelerate with normal matter field alone.
description: 6 pages: added comparisons with the Tsallis entropy case and discussions on the Bekenstein bound; references updated; version accepted by EPJC
Magnetodielectric effect in nickel nanosheet-Na-4 mica composites
Creators: name: Mitra, Sreemanta
name: Mandal, Amrita
name: Datta, Anindya
name: Banerjee, Sourish
name: Chakravorty, Dipankar
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Nickel nanosheets of thickness 0.6 nm were grown within the nanochannels of Na-4 mica template. The specimens show magnetodielectric effect at room temperature with a change of dielectric constant as a function of magnetic field, the electric field frequency varying from 100 to 700 kHz. A decrease of 5% in the value of dielectric constant was observed up to a field of 1.2 Tesla. This is explained by an inhomogeneous two-component composite model as theoretically proposed recently. The present approach will open up synthesis of various nanocomposites for sensor applications.
description: 11 pages, 7 figures
Swampland Bounds on Dark Sectors
Creators: name: Montero, Miguel
name: Muñoz, Julian B.
name: Obied, Georges
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use Swampland principles to theoretically disfavor regions of the parameter space of dark matter and other darkly charged particles that may exist. The Festina Lente bound, the analogue of the Weak-Gravity conjecture in de Sitter, places constraints on the mass and charge of dark particles, which here we show cover regions in parameter space that are currently allowed by observations. As a consequence, a broad set of new ultra-light particles are in the Swampland, independently of their cosmic abundance, showing the complementarity of Quantum Gravity limits with laboratory and astrophysical studies. In parallel, a Swampland bound on the UV cutoff associated to the axion giving a Stückelberg photon its longitudinal mode translates to a new constraint on the kinetic mixings and masses of dark photons. This covers part of the parameter space targeted by upcoming dark-photon direct-detection experiments. Moreover, it puts astrophysically interesting models in the Swampland, including freeze-in dark matter through an ultra-light dark photon, as well as radio models invoked to explain the 21-cm EDGES anomaly.
description: 31 pages, 5 figures
Discrete-Time State-Feedback Controller with Canonical Form on Inverted Pendulum (on a cart)
Creators: name: Widjiantoro, Bambang L.
name: Wafi, Moh Kamalul
Publisher: name: arXiv
Year: 2023
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The scope of inverted pendulum has been widely studied as one of the notable research with respect to standing in balance. The concept of this pendulum is similar to missile guidance, meaning that the center of drag is ahead that of gravity. Mathematical model of inverted pendulum on a cart is moreover presented in this paper. Various rewarding parameters are proposed from the displacement of the pivot, angular rotation, to external force exerted on the carriage so as to gain its equilibrium points and the linearized systems. Due to the severe risk of instability, a reliable closed-loop state feedback controller is designed to stabilize in upright position, even with large deviations. The specific concept proposed is to apply the canonical form of computing the determinant of gain $K$ leading to $K_d$. The results show that the constructed design can maintain the stability of the system by applying three sorts of initial condition and choosing sampling time $T$ under $0.2$ with small possible degrading performance.
description: 6 pages, 13 figures
Further Developments in Gold-stud Bump Bonding
Creators: name: Neher, C.
name: Lander, R. L.
name: Moskaleva, A.
name: Pasner, J.
name: Tripathi, M.
name: Woods, M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: As silicon detectors in high energy physics experiments require increasingly complex assembly procedures, the availability of a wide variety of interconnect technologies provides more options for overcoming obstacles in generic R&D. Gold ball bonding has been a staple in the interconnect industry due to its ease of use and reliability. However, due to some limitations in the standard technique, alternate methods of gold-stud bonding are being developed. This paper presents recent progress and challenges faced in the development of double gold-stud bonding and 0.5 mil wire gold-stud bonding at the UC Davis Facility for Interconnect Technology. Advantages and limitations of each technique are analyzed to provide insight into potential applications for each method. Optimization of procedures and parameters is also presented.
description: TWEPP 2011 conference proceeding, 8 pages, 7 figures
An effective singular oscillator for Duffin-Kemmer-Petiau particles with a nonminimal vector coupling: a two-fold degeneracy
Creators: name: Cardoso, T. R.
name: Castro, L. B.
name: de Castro, A. S.
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Scalar and vector bosons in the background of one-dimensional nonminimal vector linear plus inversely linear potentials are explored in a unified way in the context of the Duffin-Kemmer-Petiau theory. The problem is mapped into a Sturm-Liouville problem with an effective singular oscillator. With boundary conditions emerging from the problem, exact bound-state solutions in the spin-0 sector are found in closed form and it is shown that the spectrum exhibits degeneracy. It is shown that, depending on the potential parameters, there may or may not exist bound-state solutions in the spin-1 sector.
description: 1 figure. arXiv admin note: substantial text overlap with arXiv:1009.1597
Evidence of oblique electron acoustic solitary waves triggered by magnetic reconnection in Earth's magnetosphere
Creators: name: Atteya, A.
name: EL-Labany, S. K.
name: Karmakar, P. K.
name: Afify, M. S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Motivated by the recent Magnetospheric Multiscale (MMS) observations of oblique electron acoustic waves, we addressed the generation mechanism of the observed waves by utilizing the reductive perturbation technique. The nonlinear Zakharov-Kuznetsov (ZK) equation is derived for collisionless, magnetised plasma composed of cool inertial background electrons, the cool inertial electron beam, hot inertialess suprathermal electrons represented by a $κ$-distribution, and stationary ions. Moreover, the instability growth rate is derived by using the small-k perturbation expansion method. Our findings reveal that the structure of the electrostatic wave profile is significantly influenced by the external magnetic field, the unperturbed hot, cool, and electron beam densities, the obliquity angle, and the rate of superthermality. Such parameters also affect the instability growth rate. This study clarifies the characteristics of the oblique electron solitary waves that may be responsible for changing the electron and ion distribution functions, which alter the magnetic reconnection process. Moreover, increasing the growth rate with the plasma parameters could be a source of anomalous resistivity that enhances the rate of magnetic reconnection.
A Study of Update Request Comments in Stack Overflow Answer Posts
Creators: name: Sheikhaei, Mohammad Sadegh
name: Tian, Yuan
name: Wang, Shaowei
Publisher: name: arXiv
Year: 2023
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: Comments play an important role in updating Stack Overflow (SO) posts. They are used to point out a problem (e.g., obsolete answer and buggy code) in a SO answer or ask for more details about a proposed answer. We refer to this type of comment as update request comments (URCs), which may trigger an update to the answer post and thus improve its quality. In this study, we manually analyze a set of 384 sampled SO answer posts and their associated 1,221 comments to investigate the prevalence of URCs and how URCs are addressed. We find that around half of the analyzed comments are URCs. While 55.3% of URCs are addressed within 24 hours, 36.5% of URCs remain unaddressed after a year. Moreover, we find that the current community-vote mechanism could not differentiate URCs from non-URCs. Thus many URCs might not be aware by users who can address the issue or improve the answer quality. As a first step to enhance the awareness of URCs and support future research on URCs, we investigate the feasibility of URC detection by proposing a set of features extracted from different aspects of SO comments and using them to build supervised classifiers that can automatically identify URCs. Our experiments on 377 and 289 comments posted on answers to JavaScript and Python questions show that the proposed URC classifier can achieve an accuracy of 90% and an AUC of 0.96, on average.
description: This is the preprint version of a paper that has been accepted for publication in the Journal of Systems and Software
Aspects of Irregular Punctures via Holography
Creators: name: Bah, Ibrahima
name: Bonetti, Federico
name: Nardoni, Emily
name: Waddleton, Thomas
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We present new families of $AdS_5$ solutions in M-theory preserving 4d ${\mathcal N = 2}$ supersymmetry. We perform a systematic analysis of holographic observables for these solutions, providing evidence for an interpretation in terms of 4d superconformal field theories (SCFTs) of Argyres-Douglas type, realized in class $\mathcal S$ via a sphere with one irregular, and one regular puncture. The gravity solutions exhibit internal M5-brane sources that correspond to the irregular puncture. For a family of solutions, we identify explicitly the class $\mathcal S$ puncture data and perform a detailed match, including Higgs branch operators. For other families we comment on proposed field theory duals, based on irregular punctures labeled by nested Young tableaux.
description: 50 pages plus appendices, 11 figures
Impact of pedestal density gradient and collisionality on ELM dynamics
Creators: name: Li, Nami
name: Xu, X. Q.
name: Wang, Y. F.
name: Lin, X.
name: Yan, N.
name: Xu, G. S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: BOUT++ turbulence simulations are conducted to capture the underlying physics of the small ELM characteristics achieved by increasing separatrix density via controlling strike points from vertical to horizontal divertor plates for three EAST discharges. BOUT ++ linear simulations show that the most unstable modes change from high-n ideal ballooning modes to the intermediate-n peeling-ballooning modes and eventually to peeling-ballooning stable plasmas in the pedestal. Nonlinear simulations show that the fluctuation is saturated at a high level for the lowest separatrix density. The elm size decreases with increasing the separatrix density, until the fraction of this energy lost during the ELM crash becomes less than 1% of the pedestal stored energy, leading to small ELMs. Simulations indicate that small ELMs can be triggered either by the marginally peeling-ballooning instability near the peak pressure gradient position inside pedestal or by a local instability in the pedestal foot with a larger separatrix density gradient. The pedestal collisionality scan for type-I ELMs with steep pedestal density gradient shows that both linear growth rate and elm size decrease with collisionality increasing. While the pedestal collisionality and pedestal density width scan with a weak pedestal density gradient indicate small ELMs can either be triggered by high-n ballooning mode or by low-n peeling mode in low collisionality region 0.04~0.1. The simulations indicate the weaker the linear unstable modes near marginal stability with small linear growth rate, the lower nonlinearly saturated fluctuation intensity and the smaller turbulence spreading from the linear unstable zone to stable zone in the nonlinear saturation phase, leading to small ELMs.
Investigating $S$-wave bound states composed of two pseudoscalar mesons
Creators: name: Li, Zi-Long
name: Tan, Xing-Yue
name: Zhang, Zhu-Feng
name: Wang, Zhen-Yang
name: Guo, Xin-Heng
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this work, we systematically investigate the two-pseudoscalar meson systems with the Bethe-Salpeter equation in the ladder and instantaneous approximations. By solving the Bethe-Salpeter equation numerically with the kernel containing the one-particle exchange diagrams, we find that the $K\bar{K}$, $DK$, $B\bar{K}$, $D\bar{D}$, $B\bar{B}$, $BD$, $D\bar{K}$, $BK$, and $B\bar{D}$ systems with $I=0$ can exist as bound states. We also study the contributions from heavy meson ($J/ψ$ and $Υ$) exchanges, and we find that the contribution from heavy meson exchange can not be ignored.
description: 12 pages, 1 table, 3 figures
Electric thermal energy storage based on packed beds for renewable energy integration
Creators: name: Heyde, Michael von der
Publisher: name: TUHH Universitätsbibliothek
Year: 2022
Subjects: subject: Packed Bed
subject: Electric Thermal Energy Storage
subject: Carnot Battery
subject: System Simulation
subject: Computational Fluid Dynamics (CFD)
classificationCode: 600
subject: Technik

description: In der Arbeit wird eine neuartige Energiespeichertechnologie zur Integration fluktuierender Wind- und Solarenergie untersucht. Die Speicherung erfolgt als thermische Energie bei hoher Temperatur in einer Schüttung aus Naturstein zu geringen Kosten. Elektrisch erwärmte Luft lädt den Speicher. Die Entladung erfolgt über einen Abhitzedampferzeuger, welcher eine Turbine oder andere Verbraucher mit Dampf versorgen kann. Es wird eine dynamische Systemsimulation des Luftkreises sowie Strömungssimulation im Speicher- und Partikel-Maßstab eingesetzt. Für eine Auswahl an Anwendungsfällen werden der energetische Nutzungsgrad des Luftkreises, sowie das Verhältnis der tatsächlich nutzbaren zur nominellen thermischen Speicherkapazität bestimmt.
description: A novel energy storage technology for the integration of variable renewable energy is investigated in this work. The energy is stored as thermal energy at high-temperature in a packed bed of low-cost natural rock. Electrically heated air is used for charge and a heat recovery steam generator, which can supply steam to a turbine or other consumers, for discharge. The investigation includes dynamic system simulation of the air cycle as well as computational fluid dynamics on packed-bed and particle scale. The energy-based air cycle efficiency as well as the ratio of usable to nominal thermal storage capacity are derived for a selection of test cases.
Impact of electroweak group representation in models for $B$ and $g-2$ anomalies from Dark Loops
Creators: name: Capucha, Rodrigo
name: Huang, Da
name: Lopes, Tomás
name: Santos, Rui
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss two models which are part of a class providing a common explanation for lepton flavor universality violation in $b \to s l^+ l^- $ decays, the dark matter (DM) problem and the muon $(g-2)$ anomaly. The $B$ meson decays and the muon $(g-2)$ anomalies are explained by additional one-loop diagrams with DM candidates. The models have one extra fermion field and two extra scalar fields relative to the Standard Model (SM). The $SU(3)$ quantum numbers are fixed by the interaction with the SM fermions in a new Yukawa Lagrangian that connects the dark and the visible sectors. We compare two models, one where the fermion is a singlet and the scalars are doublets under $SU(2)_L$ and another one where the fermion is a doublet and the scalars are singlets under $SU(2)_L$. We conclude that both models can explain all new physics phenomena simultaneously, while satisfying all other flavor and DM constraints. However, there are crucial differences between how the DM constraints affect the two models leading to a noticeable difference in the allowed DM mass range.
description: 23 pages, 11 figures
Bayesian Centroid Estimation for Motif Discovery
Creators: name: Carvalho, Luis E.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences
subject: 62F15, 62P10, 65C05

description: Biological sequences may contain patterns that are signal important biomolecular functions; a classical example is regulation of gene expression by transcription factors that bind to specific patterns in genomic promoter regions. In motif discovery we are given a set of sequences that share a common motif and aim to identify not only the motif composition, but also the binding sites in each sequence of the set. We present a Bayesian model that is an extended version of the model adopted by the Gibbs motif sampler, and propose a new centroid estimator that arises from a refined and meaningful loss function for binding site inference. We discuss the main advantages of centroid estimation for motif discovery, including computational convenience, and how its principled derivation offers further insights about the posterior distribution of binding site configurations. We also illustrate, using simulated and real datasets, that the centroid estimator can differ from the maximum a posteriori estimator.
description: 24 pages, 9 figures