cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Open Research Infrastructure – supporting open research practices at Cambridge
Creators: name: Martinez Garcia, Agustina
Publisher: name: Apollo - University of Cambridge Repository
Year: 2023
Subjects: open research infrastructure
scholarly publishing
open repositories

description: Open research helps to support key features of research and innovation such as transparency, openness, verification and reproducibility and it also helps to foster collaboration within and across disciplines. Institutional support for open, suitable infrastructures that underpin research plays a key role in enabling open research practices within the research community at Cambridge, and beyond. In this talk I will provide an overview of the open research programme currently being developed, with a particular focus on those areas / projects concerned with the implementation of open systems and services to support open research practices such as alternative publishing models and the role of institutional repositories in supporting early publication of research findings in ways that maximise discovery and impact following FAIR (Findable, Accessible, Interoperable and Re-usable) principles, amongst others.
Population of Exciton-Polaritons via Luminescent sp$^{3}$ Defects in Single-Walled Carbon Nanotubes
Creators: name: Lüttgens, Jan M.
name: Berger, Felix J.
name: Zaumseil, Jana
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Semiconducting single-walled carbon-nanotubes (SWCNTs) are an interesting material for strong-light matter coupling due to their stable excitons, narrow emission in the near infrared and high charge carrier mobilities. Furthermore, they have emerged as quantum light sources as a result of the controlled introduction of luminescent quantum defects (sp$^{3}$-defects) with red-shifted transitions that enable single-photon emission. The complex photophysics of SWCNTs and overall goal of polariton condensation pose the question of how exciton-polaritons are populated and how it might be optimized. The contributions of possible relaxation processes, i.e., scattering with acoustic phonons, vibrationally assisted scattering, and radiative pumping, are investigated using angle-resolved reflectivity and time-resolved photoluminescence measurements on microcavities with a wide range of detunings. We show that the predominant population mechanism for SWCNT exciton-polaritons in planar microcavities is radiative pumping. Consequently, the limitation of polariton population due to the low photoluminescence quantum yield of nanotubes, can be overcome by luminescent sp$^{3}$ defects. Without changing the polariton branch structure, radiative pumping through these emissive defects leads to an up to 10-fold increase of the polariton population for detunings with a large photon fraction. Thus, the controlled and tunable functionalization of SWCNTs with sp$^{3}$ defects presents a viable route towards bright and efficient polariton devices.
Availability assessment of SunOS/Solaris Unix Systems based on Syslogd and wtmpx logfiles : a case study
Creators: name: Simache, Cristina
name: Kaaniche, Mohamed
Publisher: name: arXiv
Year: 2007
Subjects: subject: Performance (cs.PF)
subject: FOS: Computer and information sciences

description: This paper presents a measurement-based availability assessment study using field data collected during a 4-year period from 373 SunOS/Solaris Unix workstations and servers interconnected through a local area network. We focus on the estimation of machine uptimes, downtimes and availability based on the identification of failures that caused total service loss. Data corresponds to syslogd event logs that contain a large amount of information about the normal activity of the studied systems as well as their behavior in the presence of failures. It is widely recognized that the information contained in such event logs might be incomplete or imperfect. The solution investigated in this paper to address this problem is based on the use of auxiliary sources of data obtained from wtmpx files maintained by the SunOS/Solaris Unix operating system. The results obtained suggest that the combined use of wtmpx and syslogd log files provides more complete information on the state of the target systems that is useful to provide availability estimations that better reflect reality.
Nick Virgilio haiku archive, box 02 folder 05
Creators: name: Virgilio, Nicholas A. (Nicholas Anthony)
Publisher: name: No Publisher Supplied
Year: 1962

description: The Nicholas Virgilio Haiku Archive is primarily composed of sheets of typed haiku poems, several poems to a page, only a few ever published; some correspondence, mostly related to publishing or speaking engagements; and a small amount of personal correspondence. Virgilio lived in Camden, New Jersey and is a renowned haikuist.
Constraining Ultralight Axions with Galaxy Surveys
Creators: name: Laguë, Alex
name: Bond, J. Richard
name: Hložek, Renée
name: Rogers, Keir K.
name: Marsh, David J. E.
name: Grin, Daniel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Ultralight axions and other bosons are dark matter candidates present in many high energy physics theories beyond the Standard Model. In particular, the string axiverse postulates the existence of up to $\mathcal{O}(100)$ light scalar bosons constituting the dark sector. Considering a mixture of axions and cold dark matter, we obtain upper bounds for the axion relic density $Ω_a h^2 < 0.004$ for axions of mass $10^{-31}\;\mathrm{eV}\leq m_a \leq 10^{-26}\;\mathrm{eV}$ at 95% confidence. We also improve existing constraints by a factor of over 4.5 and 2.1 for axion masses of $10^{-25}$ eV and $10^{-32}$ eV, respectively. We use the Fourier-space galaxy clustering statistics from the Baryon Oscillation Spectroscopic Survey (BOSS) and demonstrate how galaxy surveys break important degeneracies in the axion parameter space compared to the cosmic microwave background (CMB). We test the validity of the effective field theory of large-scale structure approach to mixed ultralight axion dark matter by making our own mock galaxy catalogs and find an anisotropic ultralight axion signature in the galaxy quadrupole. We also observe an enhancement of the linear galaxy bias from 1.8 to 2.4 when allowing for 5% of the dark matter to be composed of a $10^{-28}$ eV axion in our simulations. Finally, we develop an augmented interpolation scheme allowing a fast computation of the axion contribution to the linear matter power spectrum leading to a 70% reduction of the computational cost for the full Monte Carlo Markov chains analysis.
description: Updated references
Astrophysics in Southern Africa
Creators: name: Whitelock, Patricia A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The government of South Africa has identified astronomy as a field in which their country has a strategic advantage and is consequently investing very significantly in astronomical infrastructure. South Africa now operates a 10-m class optical telescope, the Southern African Large Telescope (SALT), and is one of two countries short listed to host the Square Kilometre Array (SKA), an ambitious international project to construct a radio telescope with a sensitivity one hundred times that of any existing telescope. The challenge now is to produce an indigenous community of users for these facilities, particularly from among the black population which was severely disadvantaged under the apartheid regime. In this paper I briefly describe the observing facilities in Southern Africa before going on to discuss the various collaborations that are allowing us to use astronomy as a tool for development, and at the same time to train a new generation of astronomers who will be well grounded in the science and linked to their colleagues internationally.
description: Paper given at the 2007 meeting of the National Society of Black Physicists; 10 pages, 2 photographs. To appear in American Institute of Physics Conference Proceedings
TLSAN: Time-aware Long- and Short-term Attention Network for Next-item Recommendation
Creators: name: Zhang, Jianqing
name: Wang, Dongjing
name: Yu, Dongjin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences
subject: H.3.3

description: Recently, deep neural networks are widely applied in recommender systems for their effectiveness in capturing/modeling users' preferences. Especially, the attention mechanism in deep learning enables recommender systems to incorporate various features in an adaptive way. Specifically, as for the next item recommendation task, we have the following three observations: 1) users' sequential behavior records aggregate at time positions ("time-aggregation"), 2) users have personalized taste that is related to the "time-aggregation" phenomenon ("personalized time-aggregation"), and 3) users' short-term interests play an important role in the next item prediction/recommendation. In this paper, we propose a new Time-aware Long- and Short-term Attention Network (TLSAN) to address those observations mentioned above. Specifically, TLSAN consists of two main components. Firstly, TLSAN models "personalized time-aggregation" and learn user-specific temporal taste via trainable personalized time position embeddings with category-aware correlations in long-term behaviors. Secondly, long- and short-term feature-wise attention layers are proposed to effectively capture users' long- and short-term preferences for accurate recommendation. Especially, the attention mechanism enables TLSAN to utilize users' preferences in an adaptive way, and its usage in long- and short-term layers enhances TLSAN's ability of dealing with sparse interaction data. Extensive experiments are conducted on Amazon datasets from different fields (also with different size), and the results show that TLSAN outperforms state-of-the-art baselines in both capturing users' preferences and performing time-sensitive next-item recommendation.
Effect of time delay on feedback control of a flashing ratchet
Creators: name: Craig, E. M.
name: Long, B. R.
name: Parrondo, J. M. R.
name: Linke, H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: It was recently shown that the use of feedback control can improve the performance of a flashing ratchet. We investigate the effect of a time delay in the implementation of feedback control in a closed-loop collective flashing ratchet, using Langevin dynamics simulations. Surprisingly, for a large ensemble, a well-chosen delay time improves the ratchet performance by allowing the system to synchronize into a quasi-periodic stable mode of oscillation that reproduces the optimal average velocity for a periodically flashing ratchet. For a small ensemble, on the other hand, finite delay times significantly reduce the benefit of feedback control for the time-averaged velocity, because the relevance of information decays on a time scale set by the diffusion time of the particles. Based on these results, we establish that experimental use of feedback control is realistic.
description: 6 pages, 6 figures, to appear in Europhysics Letters
Safe Occlusion-aware Autonomous Driving via Game-Theoretic Active Perception
Creators: name: Zhang, Zixu
name: Fisac, Jaime F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: Systems and Control (eess.SY)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Autonomous vehicles interacting with other traffic participants heavily rely on the perception and prediction of other agents' behaviors to plan safe trajectories. However, as occlusions limit the vehicle's perception ability, reasoning about potential hazards beyond the field of view is one of the most challenging issues in developing autonomous driving systems. This paper introduces a novel analytical approach that poses safe trajectory planning under occlusions as a hybrid zero-sum dynamic game between the autonomous vehicle (evader) and an initially hidden traffic participant (pursuer). Due to occlusions, the pursuer's state is initially unknown to the evader and may later be discovered by the vehicle's sensors. The analysis yields optimal strategies for both players as well as the set of initial conditions from which the autonomous vehicle is guaranteed to avoid collisions. We leverage this theoretical result to develop a novel trajectory planning framework for autonomous driving that provides worst-case safety guarantees while minimizing conservativeness by accounting for the vehicle's ability to actively avoid other road users as soon as they are detected in future observations. Our framework is agnostic to the driving environment and suitable for various motion planners. We demonstrate our algorithm on challenging urban and highway driving scenarios using the open-source CARLA simulator.
description: To be appeared in Robotics: Science and Systems (RSS), 2021
Eine neue Partei ‚links von der SPD‘. Überlegungen zur Bedeutung nicht-etablierter Kleinparteien im politischen System Nordrhein-Westfalens am Beispiel der WASG und Linkspartei.PDS
Creators: name: Steuwer, Janosch
Publisher: name: Moving the Social
Year: 2015

description: Up to the present day there has been only limited academic interest in small political parties without representation in parliament. The article draws attention to this aspect discussing the role of small political parties in the political system of North Rhine-Westphalia. The institutionalisation of the new party “Die Linke” is considered as a chance to survey small parties, their general function in political systems and their evolution. The article pursues in particular the question if altered political frameworks offer new options for a more effective representation of small parties. Against this background, the paper investigates in detail the changes of PDS and WASG in North Rhine-Westphalia seeking in particular reasons responsible for success and failure. In addition, this analysis assesses the chances for a permanent parliamentary representation of the new party »Die Linke«. The paper concludes with general observations and the deduction that there is no fundamental increase in the importance of small parties.
description: Moving the Social, Vol 38 (2007): Forschungen und Forschungsberichte
Empirical analysis and statistical modeling of attack processes based on honeypots
Creators: name: Kaaniche, Mohamed
name: Deswarte, Y.
name: Alata, Eric
name: Dacier, Marc
name: Nicomette, Vincent
Publisher: name: arXiv
Year: 2007
Subjects: subject: Performance (cs.PF)
subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Honeypots are more and more used to collect data on malicious activities on the Internet and to better understand the strategies and techniques used by attackers to compromise target systems. Analysis and modeling methodologies are needed to support the characterization of attack processes based on the data collected from the honeypots. This paper presents some empirical analyses based on the data collected from the Leurr{é}.com honeypot platforms deployed on the Internet and presents some preliminary modeling studies aimed at fulfilling such objectives.
The Low CO Content of the Extremely Metal Poor Galaxy I Zw 18
Creators: name: Leroy, Adam
name: Cannon, John
name: Walter, Fabian
name: Bolatto, Alberto
name: Weiss, Axel
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present sensitive molecular line observations of the metal-poor blue compact dwarf I Zw 18 obtained with the IRAM Plateau de Bure interferometer. These data constrain the CO J=1-0 luminosity within our 300 pc (FWHM) beam to be L_CO < 1 \times 10^5 K km s^-1 pc^2 (I_CO < 1 K km s^-1), an order of magnitude lower than previous limits. Although I Zw 18 is starbursting, it has a CO luminosity similar to or less than nearby low-mass irregulars (e.g. NGC 1569, the SMC, and NGC 6822). There is less CO in I Zw 18 relative to its B-band luminosity, HI mass, or star formation rate than in spiral or dwarf starburst galaxies (including the nearby dwarf starburst IC 10). Comparing the star formation rate to our CO upper limit reveals that unless molecular gas forms stars much more efficiently in I Zw 18 than in our own galaxy, it must have a very low CO-to-H_2 ratio, \sim 10^-2 times the Galactic value. We detect 3mm continuum emission, presumably due to thermal dust and free-free emission, towards the radio peak.
description: 5 pages in emulateapj style, accepted by the Astrophysical Journal
Nachholende Europäisierung? Reaktionen und Strategien der IG Metall gegenüber der Montanunion in den 1950er Jahren
Creators: name: Jojević, Jelena
Publisher: name: Moving the Social
Year: 2015

description: Confronted with a fait accompli by the ratification of the ECSC Treaty in 1951, the biggest German metalworkers’ organization – IG Metall – initially came to the conclusion, not to support the foundation of the new community. However, switching to the year 1957, when the Treaties of Rome marked the next step of European integration, this position became significantly modified: IG Metall was not merely participating in all the trade unions related ECSC structures, but rather drew the conclusion, that the ECSC has been an economic success and that integration should be deepened. Reviewing the development of this change and its reasons, this article states that IG Metall had undergone a process of Europeanization.
description: Moving the Social, Vol 42 (2009): Deutsche Gewerkschaften und europäische Integration im 20. Jahrhundert
Comparison of high and low state X-ray spectra in the Type 1 QSO 2MASS 0918+2117
Creators: name: Pounds, K. A.
name: Wilkes, B. J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: When observed by XMM-Newton in 2003 the type 1 QSO 2MASS 0918+2117 was found to in a low flux state, some ~4-5 times fainter than during an earlier Chandra observation. The 2-6 keV spectrum was unusually hard, with evidence for a reflection-dominated continuum, while a soft excess prevented confirmation of the anticipated low energy absorber. In a second XMM-Newton observation in 2005, the X-ray flux is found to have recovered, with a 2-10 keV continuum slope now typical of broad-line active galaxy, and clear evidence for low energy absorption. We find the preferred ionisation state of the absorbing gas to be low, consistent with the red nucleus and strong optical polarisation of 2MASS 0918+2117. A residual soft excess is of similar spectral form and flux to that seen in 2003.
description: accepted for publication in Monthly Notices of the RAS
Emerging symmetric strain response and weakening nematic fluctuations in strongly hole-doped iron-based superconductors
Creators: name: Wiecki, P.
name: Frachet, M.
name: Haghighirad, A. -A.
name: Wolf, T.
name: Meingast, C.
name: Heid, R.
name: Böhmer, A. E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Electronic nematicity is often found in unconventional superconductors, suggesting its relevance for electronic pairing. In the strongly hole-doped iron-based superconductors, the symmetry channel and strength of the nematic fluctuations, as well as the possible presence of long-range nematic order, remain controversial. Here, we address these questions using transport measurements under elastic strain. By decomposing the strain response into the appropriate symmetry channels, we demonstrate the emergence of a giant in-plane symmetric contribution, associated with the growth of both strong electronic correlations and the sensitivity of these correlations to strain. We find weakened remnants of the nematic fluctuations that are present at optimal doping, but no change in the symmetry channel of nematic fluctuations with hole doping. Furthermore, we find no evidence for a nematic-ordered state in the AFe$_2$As$_2$(A = K, Rb, Cs) superconductors. These results revise the current understanding of nematicity in hole-doped iron-based superconductors.
Supplementary document for Exploiting Incoherent Synthetic Apertures in Integral Imaging for Optical Super-Resolution - 7124013.pdf
Creators: name: Ding, Yifan
name: Qiu, Yuqing
name: Wang, Qimeng
name: Cheng, Yunfan
name: Liu, Yi
name: Yang, Bo-Ru
name: Qin, Zong
Publisher: name: Optica Publishing Group
Year: 2024
Subjects: Uncategorized

description: Revised SI document
Europäische Integration und Gewerkschaften im Spiegel der Akten des DGB-Archivs (Archiv der sozialen Demokratie, Bonn)
Creators: name: Mertsching, Klaus
Publisher: name: Moving the Social
Year: 2015

description: This is the contribution "Europäische Integration und Gewerkschaften im Spiegel der Akten des DGB-Archivs (Archiv der sozialen Demokratie, Bonn)" of MTS 42 (2009).
description: Moving the Social, Vol 42 (2009): Deutsche Gewerkschaften und europäische Integration im 20. Jahrhundert
Redshifts of the Long Gamma-Ray Bursts
Creators: name: Bagoly, Z.
name: Csabai, I.
name: Meszaros, A.
name: Meszaros, P.
name: Horvath, I.
name: Balazs, L. G.
name: Vavrek, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The low energy spectra of some gamma-ray bursts' show excess components beside the power-law dependence. The consequences of such a feature allows to estimate the gamma photometric redshift of the long gamma-ray bursts in the BATSE Catalog. There is good correlation between the measured optical and the estimated gamma photometric redshifts. The estimated redshift values for the long bright gamma-ray bursts are up to z=4, while for the the faint long bursts - which should be up to z=20 - the redshifts cannot be determined unambiguously with this method. The redshift distribution of all the gamma-ray bursts with known optical redshift agrees quite well with the BATSE based gamma photometric redshift distribution.
description: published in Baltic Astronomy
An architecture-based dependability modeling framework using AADL
Creators: name: Rugina, Ana-Elena
name: Kanoun, Karama
name: Kaaniche, Mohamed
Publisher: name: arXiv
Year: 2007
Subjects: subject: Performance (cs.PF)
subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences

description: For efficiency reasons, the software system designers' will is to use an integrated set of methods and tools to describe specifications and designs, and also to perform analyses such as dependability, schedulability and performance. AADL (Architecture Analysis and Design Language) has proved to be efficient for software architecture modeling. In addition, AADL was designed to accommodate several types of analyses. This paper presents an iterative dependency-driven approach for dependability modeling using AADL. It is illustrated on a small example. This approach is part of a complete framework that allows the generation of dependability analysis and evaluation models from AADL models to support the analysis of software and system architectures, in critical application domains.
Boson Pairs in a One-dimensional Split Trap
Creators: name: Murphy, D. S.
name: McCann, J. F.
name: Goold, J.
name: Busch, Th.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We describe the properties of a pair of ultracold bosonic atoms in a one-dimensional harmonic trapping potential with a tunable zero-ranged barrier at the trap centre. The full characterisation of the ground state is done by calculating the reduced single-particle density, the momentum distribution and the two-particle entanglement. We derive several analytical expressions in the limit of infinite repulsion (Tonks-Girardeau limit) and extend the treatment to finite interparticle interactions by numerical solution. As pair interactions in double wells form a fundamental building block for many-body systems in periodic potentials, our results have implications for a wide range of problems.
description: 9 pages, 8 figures
A priori estimates for weak solutions of complex Monge-Ampère equations
Creators: name: Benelkourchi, S.
name: Guedj, V.
name: Zeriahi, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Complex Variables (math.CV)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 32W20, 32Q25, 32U05

description: Let $X$ be a compact Kähler manifold and $\om$ a smooth closed form of bidegree $(1,1)$ which is nonnegative and big. We study the classes ${\mathcal E}_χ(X,\om)$ of $\om$-plurisubharmonic functions of finite weighted Monge-Ampère energy. When the weight $χ$ has fast growth at infinity, the corresponding functions are close to be bounded. We show that if a positive Radon measure is suitably dominated by the Monge-Ampère capacity, then it belongs to the range of the Monge-Ampère operator on some class ${\mathcal E}_χ(X,\om)$. This is done by establishing a priori estimates on the capacity of sublevel sets of the solutions. Our result extends U.Cegrell's and S.Kolodziej's results and puts them into a unifying frame. It also gives a simple proof of S.T.Yau's celebrated a priori ${\mathcal C}^0$-estimate.
description: Corrected typos, added details to one proof
Supplementary document for Widely Tunable Reflection by Hybrid Ion-doped Positive-negative Chiral Nematic Liquid Crystal Under Electric Field - 7190977.pdf
Creators: name: Li, Xiaolan
name: Li, Yang
name: chen, yuzhou
name: Zhou, Dong
name: liu, yongjun
Publisher: name: Optica Publishing Group
Year: 2024
Subjects: Uncategorized

description: Widely Tunable Reflection by Hybrid Ion-doped Positive-negative Chiral Nematic Liquid Crystal Under Electric Field
Investigation of a superheated superconducting colloid
Creators: name: Da Silva, Angela Jane
Publisher: name: University of British Columbia
Year: 2010

description: In recent years, there has been increasing interest in the idea of using a superheated superconducting colloid (SSC) as a detector for neutrinos and dark matter candidates. The primary objective of this work has been to investigate the basic properties of an SSC, consisting of 7 μm radius tin grains imbedded in epoxy, using a pumped ⁴He cryostat with a low vibrational noise RF-SＱUID readout system. The superheating-supercooling hysteresis curves of the colloid have been measured in applied magnetic fields ranging from 3.1 x 10⁻⁴T to 1.4 x 10⁻²T. The superconducting to normal phase transition in individual grains inside the colloid has been observed and the measured signal size is in reasonable agreement with the calculated values. Finally, it was demonstrated that the colloid could withstand up to 20Mrad of [omitted]-radiation without incurring a significant change in its superconducting-normal phase transition. A new type of sample, consisting of a planar array of 1 μm thick metal squares deposited on a mylar substrate, was developed. Both indium and tin were used as a. fabrication material. The characteristics of such samples were investigated, again using the pumped ⁴He cryostat. The full Meissner effect was only observed for applied magnetic fields less than 5 x 10⁻⁵T. For higher applied fields, the samples behaved like type-[omitted] superconductors in the mixed state regime, exhibiting flux penetration and trapping.
p-Adic and Adelic Rational Dynamical Systems
Creators: name: Dragovich, Branko
name: Mihajlovic, Dusan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: Dynamical Systems (math.DS)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In the framework of adelic approach we consider real and p-adic properties of dynamical system given by linear fractional map f (x) = (a x + b)/(c x + d), where a, b, c and d are rational numbers. In particular, we investigate behavior of this adelic dynamical system when fixed points are rational. It is shown that any of rational fixed points is p-adic indifferent for all but a finite set of primes. Only for finite number of p-adic cases a rational fixed point may be attractive or repelling. The present analysis is a continuation of the paper math-ph/0612058. Some possible generalizations are discussed.
description: 12 pages. Talk at the 4th Summer School in Modern Mathematical Physics, September 2006, Belgrade (Serbia)
Effect of electron-electron interaction on the phonon-mediated spin relaxation in quantum dots
Creators: name: Climente, Juan I.
name: Bertoni, Andrea
name: Goldoni, Guido
name: Rontani, Massimo
name: Molinari, Elisa
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We estimate the spin relaxation rate due to spin-orbit coupling and acoustic phonon scattering in weakly-confined quantum dots with up to five interacting electrons. The Full Configuration Interaction approach is used to account for the inter-electron repulsion, and Rashba and Dresselhaus spin-orbit couplings are exactly diagonalized. We show that electron-electron interaction strongly affects spin-orbit admixture in the sample. Consequently, relaxation rates strongly depend on the number of carriers confined in the dot. We identify the mechanisms which may lead to improved spin stability in few electron (>2) quantum dots as compared to the usual one and two electron devices. Finally, we discuss recent experiments on triplet-singlet transitions in GaAs dots subject to external magnetic fields. Our simulations are in good agreement with the experimental findings, and support the interpretation of the observed spin relaxation as being due to spin-orbit coupling assisted by acoustic phonon emission.
description: 12 pages, 10 figures. Revised version. Changes in section V (simulation of PRL 98, 126601 experiment)
Connected Operators for the Totally Asymmetric Exclusion Process
Creators: name: Golinelli, O.
name: Mallick, K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We fully elucidate the structure of the hierarchy of the connected operators that commute with the Markov matrix of the Totally Asymmetric Exclusion Process (TASEP). We prove for the connected operators a combinatorial formula that was conjectured in a previous work. Our derivation is purely algebraic and relies on the algebra generated by the local jump operators involved in the TASEP. Keywords: Non-Equilibrium Statistical Mechanics, ASEP, Exact Results, Algebraic Bethe Ansatz.
description: 10 pages
Limits of the uni-directional pulse propagation approximation
Creators: name: Kinsler, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: I apply the method of characteristics to both bi-directional and uni-directional pulse propagation in dispersionless media containing nonlinearity of arbitrary order. The differing analytic predictions for the shocking distance quantify the effects of the uni-directional approximation used in many pulse propagation models. Results from numerical simulations support the theoretical predictions, and reveal the nature of the coupling between forward and backward waves.
description: 6 pages, 6 figures; this version contains an additional appendix not present in the published version
The investigation of indium halides and graphite intercalation compounds using time-differential perturbed angular correlation gamma-ray spectrosocopy
Creators: name: Dong, Sunny Ronald
Publisher: name: University of British Columbia
Year: 2010

description: This thesis discusses in general terms the theory and application of time-differential perturbed angular correlation gamma-ray spectroscopy (TDPAC) to the study of solid state physics. The technique yields valuable information on the electric field gradients experienced by radionuclides which have been substituted for nonradioactive isotopes or inserted as impurities into various inorganic compounds. The indium halides are examined in a series of experiments. The first applications of this technique to the study of graphite intercalation compounds are discussed.
Proposal for an Enhanced Optical Cooling System Test in an Electron Storage Ring
Creators: name: Bessonov, E. G.
name: Gorbunkov, M. V.
name: Mikhailichenko, A. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: We are proposing to test experimentally the new idea of Enhanced Optical Cooling (EOC) in an electron storage ring. This experiment will confirm new fundamental processes in beam physics and will demonstrate new unique possibilities with this cooling technique. It will open important applications of EOC in nuclear physics, elementary particle physics and in Light Sources (LS) based on high brightness electron and ion beams.
description: 21 pages, pdf. The number of electrons in the bunch in the example is decreased, the volume of the paper is increased, Misprints are corrected
Oxygen changes crack modes of Ni-based single crystal superalloy
Creators: name: Li, Xueqiao
name: Liu, Yinong
name: Zhao, Yunsong
name: Chen, Yanhui
name: Li, Ang
name: Zhang, Jianfei
name: Zhai, Yadi
name: Li, Zhipeng
name: Ma, Dongfeng
name: Li, Xiaochen
name: Zhang, Qing
name: Yang, Xiaomeng
name: Long, Haibo
name: Mao, Shengcheng
name: Zhang, Ze
name: Han, Xiaodong
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biochemistry
subject: Physical Sciences not elsewhere classified
subject: Biotechnology
subject: Ecology
subject: FOS: Biological sciences
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Science Policy
subject: Computational Biology

description: Oxygen-affected cracking commonly presents on thin Ni-based single crystal superalloy components serving in high temperature and oxidizing environments. This study uses a newly developed in-situ thermal-stress environmental transmission electron microscope to investigate the oxidation and fracture behaviors of Ni-based single crystal superalloy at 650°C under stress. The in-situ oxidation was found to change the tensile fracture mode from the close-packed {111} planes of plastic fracture to {001} planes adjacent to γ/γ′ interfaces of brittle fracture. The microanalysis also revealed that the γ′ This paper firstly time provides direct in-situ oxygen-affected cracking behavior.
Inversion model validation of ground emissivity. Contribution to the development of SMOS algorithm
Creators: name: Demontoux, François
name: Crom, Bénédicte Le
name: Ruffié, Gilles
name: Wigneron, Jean Pierre
name: Grant, Jennifer
name: Hernandez, Daniel Medina
Publisher: name: arXiv
Year: 2007
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: SMOS (Soil Moisture and Ocean Salinity), is the second mission of 'Earth Explorer' to be developed within the program 'Living Planet' of the European Space Agency (ESA). This satellite, containing the very first 1.4GHz interferometric radiometer 2D, will carry out the first cartography on a planetary scale of the moisture of the grounds and the salinity of the oceans. The forests are relatively opaque, and the knowledge of moisture remains problematic. The effect of the vegetation can be corrected thanks a simple radiative model. Nevertheless simulations show that the effect of the litter on the emissivity of a system litter + ground is not negligible. Our objective is to highlight the effects of this layer on the total multi layer system. This will make it possible to lead to a simple analytical formulation of a model of litter which can be integrated into the calculation algorithm of SMOS. Radiometer measurements, coupled to dielectric characterizations of samples in laboratory can enable us to characterize the geological structure. The goal of this article is to present the step which we chose to validate this analytical model.
The IDV source J1128+5925, a new candidate for annual modulation?
Creators: name: Gabanyi, K. E.
name: Marchili, N.
name: Krichbaum, T. P.
name: Britzen, S.
name: Fuhrmann, L.
name: Witzel, A.
name: Zensus, J. A.
name: Muller, P.
name: Liu, X.
name: Song, H. G.
name: Han, J. L.
name: Sun, X. H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Short time-scale radio variations of compact extragalactic radio sources, known as IntraDay Variability, can be explained in at least some sources by a source-extrinsic effect, in which the variations are interpreted as scintillation of radio waves caused by the turbulent ISM of the Milky Way. One of the most convincing observational arguments in favour of propagation-induced variability is the so called annual modulation of the characteristic variability time-scale, which is due to the orbital motion of the Earth. Data for the recently discovered and highly variable IDV source J1128+5925 are presented. We study the frequency and time dependence of the IDV in this compact quasar. We measure the characteristic variability time-scale of the IDV throughout the year, and analyze whether the observed changes in the variability time-scale are consistent with annual modulation. We monitored the flux density variability of J1128+5925 with dense time sampling between 2.7 and 10.45GHz with the 100m Effelsberg radio telescope of the MPIfR and with the 25m Urumqi radio telescope. From ten observing sessions, we determine the variability characteristics and time-scales. The observed pronounced changes of the variability time-scale of J1128+5925 are modelled with an anisotropic annual modulation model. The observed frequency dependence of the variation is in good agreement with the prediction from interstellar scintillation. Adopting a simple model for the annual modulation model and using also the frequency dependence of the IDV, we derive a lower limit to the distance of the scattering screen and an upper limit to the scintillating source size. The latter is found to be consistent with the measured core size from VLBI.
description: 15 pages, 9 figures Accepted for publication in Astronomy and Astrophysics
Model-independent Analysis of Lepton Flavour Violating Tau Decays
Creators: name: Dassinger, B. M.
name: Feldmann, Th.
name: Mannel, Th.
name: Turczyk, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Many models for physics beyond the Standard Model predict lepton-flavour violating decays of charged leptons at a level which may become observable very soon. In the present paper we investigate the decays of a Tau into three charged leptons in a generic way, based on effective-field-theory methods, where the relevant operators are classified according to their chirality structure. We work out the decay distributions and discuss phenomenological implications.
description: 14 pages, 10 figures, references and comments added
Predicting the frequencies of diverse exo-planetary systems
Creators: name: Greaves, J. S.
name: Fischer, D. A.
name: Wyatt, M. C.
name: Beichman, C. A.
name: Bryden, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Extrasolar planetary systems range from hot Jupiters out to icy comet belts more distant than Pluto. We explain this diversity in a model where the mass of solids in the primordial circumstellar disk dictates the outcome. The star retains measures of the initial heavy-element (metal) abundance that can be used to map solid masses onto outcomes, and the frequencies of all classes are correctly predicted. The differing dependences on metallicity for forming massive planets and low-mass cometary bodies are also explained. By extrapolation, around two-thirds of stars have enough solids to form Earth-like planets, and a high rate is supported by the first detections of low-mass exo-planets.
description: 5 pages, 2 figures; accepted by MNRAS
Theory of the fractional microwave-induced resistance oscillations
Creators: name: Dmitriev, I. A.
name: Mirlin, A. D.
name: Polyakov, D. G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We develop a systematic theory of microwave-induced oscillations in magnetoresistivity of a 2D electron gas in the vicinity of fractional harmonics of the cyclotron resonance, observed in recent experiments. We show that in the limit of well-separated Landau levels the effect is dominated by a change of the distribution function induced by multiphoton processes. At moderate magnetic field, a single-photon mechanism originating from the microwave-induced sidebands in the density of states of disorder-broadened Landau levels becomes important.
description: 4 pages, 2 figures; V2: published version (typos corrected, references added and updated)
Soft and hard X-ray excess emission in Abell 3112 observed with Chandra
Creators: name: Bonamente, M.
name: Nevalainen, J.
name: Lieu, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Chandra ACIS-S observations of the galaxy cluster A3112 feature the presence of an excess of X-ray emission above the contribution from the diffuse hot gas, which can be equally well modeled with an additional non-thermal power-law model or with a low-temperature thermal model of low metal abundance. We show that the excess emission cannot be due to uncertainties in the background subtraction or in the Galactic HI column density. Calibration uncertainties in the ACIS detector that may affect our results are addressed by comparing the Chandra data to XMM MOS and PN spectra. While differences between the three instruments remain, all detect the excess in similar amounts, providing evidence against an instrumental nature of the excess. Given the presence of non-thermal radio emission near the center of A3112, we argue that the excess X-ray emission is of non-thermal nature and distributed throughout the entire X-ray bandpass, from soft to hard X-rays. The excess can be explained with the presence of a population of relativistic electrons with ~7% of the cluster's gas pressure. We also discuss a possible thermal nature of the excess, and examine the problems associated with such interpretation.
description: Ap.J. in press, emulateapj style
500 W Peak Power Cavity Dumped 2-micron GaSb-Based VECSEL
Creators: name: Hoehler, Jacob
name: Gibson, Ricky
name: Reed, Jennifer
name: Bedford, Robert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: A single transverse mode high pulse-energy VECSEL was developed. The GaSb based VECSEL emits at a wavelength of 2.04 microns with a peak power exceeding 500W while maintaining good beam quality. The cavity employs a Pockels cell combined with a low-loss thin film polarizer to selectively dump the intracavity energy into a 10ns pulse. The laser has promise for incoherent LiDAR, materials processing, gas sensing, and nonlinear optics.
description: 10 PAGES, 5 FIGURES
Gross-Neveu Heisenberg criticality: dynamical generation of quantum spin Hall masses
Creators: name: Liu, Yuhai
name: Wang, Zhenjiu
name: Sato, Toshihiro
name: Guo, Wenan
name: Assaad, Fakher F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We consider fermions on a honeycomb lattice supplemented by a spin invariant interaction that dynamically generates a quantum spin Hall insulator. This lattice model provides an instance of Gross-Neveu Heisenberg criticality, as realized for example by the Hubbard model on the honeycomb lattice. Using auxiliary field quantum Monte Carlo simulations we show that we can compute with unprecedented precision susceptibilities of the order parameter. In O(N) Gross-Neveu transitions, the anomalous dimension of the bosonic mode grows as a function of N such that in the large-N limit it is of particular importance to consider susceptibilities rather than equal time correlations so as to minimize contributions from the background. For the N=3 case, we obtain $1/ν=1.11(4)$, $η_ϕ=0.80(9)$, and $η_ψ=0.29(2)$ for respectively the correlation length exponent, bosonic and fermionic anomalous dimensions.
description: 11 pages,13 figures
Conditions for the existence of zero-determinant strategies under observation errors in repeated games
Creators: name: Mamiya, Azumi
name: Miyagawa, Daiki
name: Ichinose, Genki
Publisher: name: arXiv
Year: 2021
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences
subject: 91A05, 91A40

description: Repeated games are useful models to analyze long term interactions of living species and complex social phenomena. Zero-determinant (ZD) strategies in repeated games discovered by Press and Dyson in 2012 enforce a linear payoff relationship between a focal player and the opponent. This linear relationship can be set arbitrarily by a ZD player. Hence, a subclass of ZD strategies can fix the opponent's expected payoff and another subclass of the strategies can exceed the opponent for the expected payoff. Since this discovery, theories for ZD strategies are extended to cope with various natural situations. It is especially important to consider the theory of ZD strategies for repeated games with a discount factor and observation errors because it allows the theory to be applicable in the real world. Recent studies revealed their existence of ZD strategies even in repeated games with both factors. However, the conditions for the existence has not been sufficiently analyzed. Here, we mathematically analyzed the conditions in repeated games with both factors. First, we derived the thresholds of a discount factor and observation errors which ensure the existence of Equalizer and positively correlated ZD (pcZD) strategies, which are well-known subclasses of ZD strategies. We found that ZD strategies exist only when a discount factor remains high as the error rates increase. Next, we derived the conditions for the expected payoff of the opponent enforced by Equalizer as well as the conditions for the slope and base line payoff of linear lines enforced by pcZD. As a result, we found that, as error rates increase or a discount factor decreases, the conditions for the linear line that Equalizer or pcZD can enforce become strict.
description: 25 pages, 4 figures
The bimodality of type Ia Supernovae
Creators: name: Mannucci, F.
name: Panagia, N.
name: Della Valle, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We comment on the presence of a bimodality in the distribution of delay time between the formation of the progenitors and their explosion as type Ia SNe. Two "flavors" of such bimodality are present in the literature: a "weak" bimodality, in which type Ia SNe must explode from both young and old progenitors, and a "strong" bimodality, in which about half of the systems explode within 10^8 years from formation. The "weak" bimodality is observationally based on the dependence of the rates with the host galaxy SFR, while the "strong" one on the different rates in radio-loud and radio-quiet early-type galaxies. We review the evidence for these bimodalities. Finally, we estimate the fraction of SNe which are missed by optical and near-IR searches because of dust extinction in massive starbursts.
description: 5 pages, to appear in the AIP conference proceedings of "Supernova 1987A: 20 Years after Supernovae and Gamma-Ray Bursters", Feb 19-23, 2007, Aspen, CO. Replaced figure 1