cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Devendra Lal - Bibliography from Devendra Lal. 14 February 1929—1 December 2012
Creators: name: J. N. Goswami
name: J. D. Macdougall
Publisher: name: The Royal Society
Year: 2021
Subjects: subject: 20202 Nuclear Physics
subject: FOS: Physical sciences

description: Devendra Lal was an Indian nuclear physicist who began his career studying particle physics while a student at the Tata Institute of Fundamental Research (TIFR) in Bombay, using tracks in nuclear emulsions to study cosmic ray particles and their interactions. He soon moved on to the search for radionuclides produced in the atmosphere by cosmic ray bombardment, independently (with colleagues) discovering radioisotopes of Be, P and Si and using them as geophysical tracers for atmospheric, meteorological and oceanographic processes. His career revolved principally around multiple aspects of cosmic rays, employing theory and experiment to examine their flux, chemical composition and energy spectrum, both at present and in the past through (for example) studies of particle tracks in the minerals of meteorites and lunar samples. He played a major role in developing approaches for the use of terrestrial cosmic-ray-produced isotopes as dating tools and tracers for a wide range of Earth processes, from biological cycles in the ocean to landscape evolution and ice ablation in the Antarctic. At various stages of his career Lal was professor at TIFR and led the geophysics group there, was professor and director of the Physical Research Laboratory in Ahmedabad, India, and was professor at the Scripps Institution of Oceanography, University of California San Diego. He was elected fellow of numerous scientific organizations and academies internationally, and was the recipient of many scientific awards and prizes.
Determining earthquake source properties, seismic attenuation and site amplification using the Indonesian strong-motion network
Creators: name: Gunawan, Indra
Publisher: name: The Australian National University
Year: 2014

description: Distinguishing source, path, and site responses from S-wave displacement spectra recorded by the Indonesian strong motion network is the objective of my Master's degree research. In this research, a well-established, nonlinear parameterization of the earthquake source and path components of the observed spectra was used, while site response is considered as an arbitrary function of frequency that multiples the source and path spectra. This model for the S-wave displacement spectra is fit to the data by combining a non-linear optimization for source and path parameters with a linear inversion for the site response spectra. Because it combines linear and nonlinear optimization, we refer to this as a 'hybrid' method. Before inverting actual observed spectra, the ability of such spectral inversions to separate source, path and site effects was explored by analyzing synthetic spectra using a grid search method. Three cases involving different types of data sets and different constraints on site response were considered, and it was determined that use of a reference site having known site response was critical to avoid strong trade-offs amongst source, path and site parameters. However, it was determined that when such a reference site is used, a simple optimization algorithm such as the Nelder-Mead Simplex algorithm could resolve the parameters reasonably well. S-wave displacement spectra of clustered earthquakes recorded by several stations were simultaneous fit by using the hybrid inversion method. Four earthquake clusters were considered: the 02 September 2009, Tasikmalaya, West Java intraslab earthquakes; the 14 June 2011, Tapanuli, North Sumatra crustal earthquakes; the 03 September 2012, Banyuwangi, East Java interslab earthquake; and the 13 June 2013, Tasikmalaya, West Java interslab earthquakes. I found that Q(f) is lower for crustal earthquakes compared with intraslab and megathrust earthquakes. From earthquake properties, the average stress drops are higher for crustal and intraslab earthquakes compared with the two megathrust earthquakes, 9.43 MPa with standard deviation 3.98, 13.31 MPa with standard deviation 0.29, 2.73 MPa with standard deviation 1.38, and 9.07 MPa with standard deviation 2.04, respectively. Finally, the site information for the 20 Indonesian Strong-Motion Network stations that recorded these earthquakes are mostly comparable with H/V measurements of dominant period. However, amplification factor from that spectral analyses are higher compared with the H/V measurements. Our study demonstrates that the hybrid approach to inversion of S-wave displacement spectra is a reliable method for simultaneous estimation of source, path, and site response. I have also obtained important new information about Indonesian earthquakes, seismic wave propagation in the Indonesian region, and site response selected stations of the Indonesian Strong Motion Network.
An Uneven Vacuum Energy Fluid as $Λ$, Dark Matter, MOND and Lens
Creators: name: Zhao, HongSheng
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Various TeVeS-inspired and f(R)-inspired theories of gravity have added an interesting twist to the search for dark matter and vacuum energy, modifying the landscape of astrophysics day by day. These theories can be together called a {\bf N}on-{\bf u}niform Dark Energy fluid (a Nu-Lambda fluid or a ${\mathbf VΛ}$ fluid); a common thread of these theories, according of an up-to-date summary by HZL \cite{Halle}, is a non-uniform vector field, describing an uneven vacuum energy fluid. The so-called "alternative" gravity theories are in fact in the standard GR gravity framework except that the cosmological "constant" is replaced by a non-trivial non-uniform vacuum energy, which couples the effects of Dark Matter and Dark Energy together by a single field. Built initially bottom-up rather than top-down as most gravity theories, TeVeS-inspired theories are healthily rooted on empirical facts. Here I attempt a review of some sanity checks of these fast-developing theories from galaxy rotation curves, gravitational lensing and cosmic acceleration. I will also discuss some theoretical aspects of the vacuum energy, and point out some analogies with electromagnetism and the Casimir effect.
description: Invited Brief (15p) Review for Modern Physics Letters A. Added references and a discussion of Kuzmin lens. Comments Very Welcome
Definition and parametrization of non-perturbative effects in quenched QCD
Creators: name: Denbleyker, A.
name: Du, D.
name: Meurice, Y.
name: Naides, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The notion of a non-perturbative effect is ambiguous if it requires the subtraction of a perturbative part defined by a diverging series. A common procedure consists in dropping the order of minimal contribution and the higher orders. This allows us to isolate very accurately the one-instanton effect for the double-well potential. For the one plaquette gauge theory, an exact analytical expression can be written for the non-perturbative part. We report recent attempts to extend this approach to the average plaquette of quenched QCD. Our goal is to express the non-perturbative effects in terms of expressions of the form beta^B exp(-A beta) calculable semi-classically. The situation is complicated by zeroes of the partition function in the complex $β$ plane (presumably near 5.75 pm i 0.2). We discuss two methods to describe the intermediate and large order behavior of the perturbative series. One is inspired by mean field theory (logarithmic specific heat) and reproduces accurately the known perturbative series with only two free parameters. A diagrammatic interpretation of this fact is still lacking. The other is based on infra-red renormalons with a factorial growth showing up at order larger than 20 and a possible effective theory interpretation. These extrapolations are compatible with the non-perturbative part of the plaquette being proportional to a^4. We propose an exponential parametrization to the corrections to the universal part of the beta function and find results compatible with the suggestion of a^2 corrections made by C. Allton.
description: 8 pages, 3 figures, Lattice 2006
Probing the capability of future direct imaging missions to spectrally constrain the frequency of Earth-like planets
Creators: name: Checlair, Jade H.
name: Villanueva, Geronimo L.
name: Hayworth, Benjamin P. C.
name: Olson, Stephanie L.
name: Komacek, Thaddeus D.
name: Robinson, Tyler D.
name: Popovic, Predrag
name: Yang, Huanzhou
name: Abbot, Dorian S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: A critical question in astrobiology is whether exoEarth candidates (EECs) are Earth-like, in that they originate life that progressively oxygenates their atmospheres similarly to Earth. We propose answering this question statistically by searching for O2 and O3 on EECs with missions such as HabEx or LUVOIR. We explore the ability of these missions to constrain the fraction, fE, of EECs that are Earth-like in the event of a null detection of O2 or O3 on all observed EECs. We use the Planetary Spectrum Generator to simulate observations of EECs with O2 and O3 levels based on Earth's history. We consider four instrument designs: LUVOIR-A (15m), LUVOIR-B (8m), HabEx with a starshade (4m, "HabEx/SS"), HabEx without a starshade (4m, "HabEx/no-SS"); as well as three estimates of the occurrence rate of EECs (eta_earth): 24%, 5%, and 0.5%. In the case of a null-detection, we find that for eta_earth = 24%, LUVOIR-A, LUVOIR-B, and HabEx/SS would constrain fE to <= 0.094, <= 0.18, and <= 0.56, respectively. This also indicates that if fE is greater than these upper limits, we are likely to detect O3 on at least 1 EEC. Conversely, we find that HabEx/no-SS cannot constrain fE, due to the lack of an coronagraph ultraviolet channel. For eta_earth = 5%, only LUVOIR-A and LUVOIR-B would be able to constrain fE, to <= 0.45 and <= 0.85, respectively. For eta_earth = 0.5%, none of the missions would allow us to constrain fE, due to the low number of detectable EECs. We conclude that the ability to constrain fE is more robust to uncertainties in eta_earth for missions with larger aperture mirrors. However all missions are susceptible to an inconclusive null detection if eta_earth is sufficiently low.
description: Accepted at The Astronomical Journal, January 7 2021. arXiv admin note: substantial text overlap with arXiv:2008.03952
Recent progress of avalanche photodiodes in high-resolution X-rays and Gamma-rays detection
Creators: name: Kataoka, J.
name: Saito, T.
name: Kuramoto, Y.
name: Ikagawa, T.
name: Yatsu, Y.
name: Kotoku, J.
name: Arimoto, M.
name: Kawai, N.
name: Ishikawa, Y.
name: Kawabata, N.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and Gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4 % for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20deg. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 nsec (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4+-0.3 % and 4.9+-0.2 % were obtained for 59.5 keV and 662 keV Gamma-rays, respectively, as measured with a CsI(Tl) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim APD array, which we present in this paper, will be a promising device for a wide-band X-ray and Gamma-ray imaging detector in future space research and nuclear medicine.
description: 11 pages, 7 figures, accepted by NIM-A
Cryogenic spin Seebeck effect
Creators: name: Elyasi, Mehrdad
name: Bauer, Gerrit E. W.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a theory of the non-linearities of the spin Seebeck effect (SSE) in a ferromagnetic nanowire at cryogenic temperatures. We adopt a microscopic quantum noise model based on a collection of two-level systems. At certain positions of Pt detectors to the wire, the transverse SSE changes sign as a function of temperature and/or temperature gradient. On the other hand, the longitudinal SSE does not show significant non-linearities even far outside the regime of validity of linear response theory.
Structural and Dynamical Fingerprints of the Anomalous Dielectric Properties of Water Under Confinement
Creators: name: Ahmadabadi, Iman
name: Esfandiar, Ali
name: Hassanali, Ali
name: Ejtehadi, Mohammad Reza
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: There is a long-standing question about the molecular configuration of interfacial water molecules in the proximity of solid surfaces, particularly carbon atoms which play a crucial role in electrochemistry and biology. In this study, the dielectric, structural and dynamical properties of confined water placed between two parallel graphene walls at different inter distances from the Angstrom scale to few tens of nanometer have been investigated using molecular dynamics. For dielectric properties of water, we show that the perpendicular component of water dielectric constant drastically decreases under sub $2\; nm$ spatial confinement. The achieved dielectric constant data through linear response and fluctuation-dissipation theory, are consistent with recent reported experimental results. By determining the charge density as well as fluctuations in the number of atoms, we provide a molecular rationale for the behavior of perpendicular dielectric response function. We also interpret the behavior of the dielectric response in terms of the presence of dangling O-H bonds of waters. By examining the residence time and lateral diffusion constant of water under confinement, we reveal that the water molecules tend to keep their hydrogen bond networks at the interface of water-graphene. We also found consistency between lateral diffusion and z-component of variance in the center of mass of the system as a function of confinement.
Non-local Branching Superprocesses and Some Related Models
Creators: name: Dawson, Donald A.
name: Gorostiza, Luis G.
name: Li, Zenghu
Publisher: name: arXiv
Year: 2006
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J80

description: A new formulation of non-local branching superprocesses is given from which we derive as special cases the rebirth, the multitype, the mass-structured, the multilevel and the age-reproduction-structured superprocesses and the superprocess-controlled immigration process. This unified treatment simplifies considerably the proof of existence of the old classes of superprocesses and also gives rise to some new ones.
Synchronous LoRa Communication by Exploiting Large-Area Out-of-Band Synchronization
Creators: name: Beltramelli, Luca
name: Mahmood, Aamir
name: Ferrari, Paolo
name: Österberg, Patrik
name: Gidlund, Mikael
name: Sisinni, Emiliano
Publisher: name: arXiv
Year: 2020
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Many new narrowband low-power wide-area networks (LPWANs) (e.g., LoRaWAN, Sigfox) have opted to use pure ALOHA-like access for its reduced control overhead and asynchronous transmissions. Although asynchronous access reduces the energy consumption of IoT devices, the network performance suffers from high intra-network interference in dense deployments. Contrarily, synchronous access can improve throughput and fairness, but it requires time synchronization. Unfortunately, maintaining synchronization over the narrowband LPWANs wastes channel time and transmission opportunities. In this paper, we propose the use of out-of-band time-dissemination to relatively synchronize LoRa devices and thereby facilitate resource-efficient slotted uplink communication. To this end, we conceptualize and analyze a co-designed synchronization and random access mechanism that can effectively exploit technologies providing limited time accuracy, such as FM radio data system (FM-RDS). While considering the LoRa-specific parameters, we derive the throughput of the proposed mechanism, compare it to a generic synchronous random access using in-band synchronization, and design the communication parameters under time uncertainty. We scrutinize the transmission time uncertainty of a device by introducing a clock error model that accounts for the errors in the synchronization source, local clock, propagation delay, and transceiver's transmission time uncertainty. We characterize the time uncertainty of FM-RDS with hardware measurements and perform simulations to evaluate the proposed solution. The results, presented in terms of success probability, throughput, and fairness for a single-cell scenario, suggest that FM-RDS, despite its poor absolute synchronization, can be used effectively to realize slotted LoRa communication with performance similar to that of more accurate time-dissemination technologies.
description: 12 pages, 8 figures, final version to appear in IEEE Internet of Things Journal
Probabilistic modelling of debris flow travel distance using empirical volumetric relationships
Creators: name: Wise, Michael Paul
Publisher: name: University of British Columbia
Year: 2009

description: Debris flows can occur on both forested (natural) and clearcut (logged) hillslopes in coastal British Columbia. Prediction of the travel distance of a potential debris flow event prior to clearcut harvesting is important to accurately assess the risk to downslope environmental resources. The travel distance is the distance from the point of initiation of a debris flow to the point of terminal deposition at the end of the flow path. Forensic data from 449 debris flow events in the Queen Charlotte Islands are used to charactrerize debris flow events in terrain where clearcut logging has been carried out. From these data, a subset of 131 events are used for the development of regression equations to calculate entrainment volume and deposition volume along distinct reaches of a debris flow event path. Slope morphology and geometry along the path, as well as the flow volume entering the reach, are used as input parameters for the regression equations. The regression equations are applied in an empirical-statistical model which uses the cumulative debris flow volume along the event path as a basis for determining the travel distance of debris flow events. The cumulative flow volume is defined as the volume of the flow as the event travels down the path, with the entrainment of debris material increasing the flow volume and the deposition of material decreasing the flow volume. Back-analyses of debris flow events were carried out for 20 independent events in the Queen Charlotte Islands and 17 events in other areas of coastal British Columbia. The model showed reasonable agreement with the peak cumulative flow volume, and the travel distance, of debris flow events reported from observations and surveys in the field. An observed variability in the forensic data was incorporated to create the empirical-statistical model UBCDFLOW. Variations in initial volume, as well as flow width, are used repeatedly to simulate the cumulative debris flow volume along a potential travel path. The probability of an event reaching a point along the path is determined based from the travel distances of these simulated flows. A comparative study of different the scenarios using UBCDFLOW illustrates that for confined flow events in gully channels, the initiation location is an important factor in determining travel distance, whereas the size of the initial volume is an important factor for unconfined flows on open slopes.
Vie et système chez G.W.F. Hegel
Creators: name: Chaput, Emmanuel
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2022
Subjects: G.W.F. Hegel
Vie
Postkantisme
Organicisme
Kénose
F.H. Jacobi

description: Cette thèse s’intéresse au traitement de la notion de vie au sein du système hégélien. Que ce soit comme vie logique, organique ou comme vie de l’esprit, cette notion représente un élément structurant dans le discours philosophique de Hegel. À un point tel que l’on peut, à partir de la systématicité dynamique de la vie et du vivant tel qu’ils sont thématisés chez Hegel, penser le caractère dynamique et vivant du système hégélien. Ce faisant, nous sommes en mesure de situer l’entreprise hégélienne dans le contexte de la philosophie postkantienne visant à un renouvellement de la pratique philosophique comme philosophie vivante capable d’articuler raison spéculative et vie pratique. Cela permet également de mieux situer l’entreprise hégélienne vis-à-vis des critiques tendant à faire de son système un système clos et ossifié. Partant du système hégélien tel qu’il se présente au cours de la période berlinoise au sein de l’Encyclopédie des sciences philosophiques, nous retraçons ainsi l’entreprise hégélienne dans sa volonté de penser à la fois la vie de la pensée et la rationalité du vivant.
Configurational entropy in $f(T)$ gravity
Creators: name: Bhattacharjee, Snehasish
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The evolution of the configurational entropy of the universe relies on the growth rate of density fluctuations and on the Hubble parameter. In this work, I present the evolution of configurational entropy for the power-law $f(T)$ gravity model of the form $f(T) = ζ(-T)^ b$, where, $ζ= (6 H_{0}^{2})^{(1-s)}\frac{Ω_{P_{0}}}{2 s -1}$ and $b$ a free parameter. From the analysis, I report that the configurational entropy in $f(T)$ gravity is negative and decreases with increasing scale factor and therefore consistent with an accelerating universe. The decrease in configurational entropy is the highest when $b$ vanishes since the effect of dark energy is maximum when $b=0$. Additionally, I find that as the parameter $b$ increases, the growth rate, growing mode, and the matter density parameter evolve slowly whereas the Hubble parameter evolves rapidly. The rapid evolution of the Hubble parameter in conjunction with the growth rate for the $b=0$ may provide an explanation for the large dissipation of configurational entropy.
description: Published in EPJ Plus
Fabrication and characterization of elongate solar cells
Creators: name: Fong, Kean Chern
Publisher: name: The Australian National University
Year: 2018
Subjects: subject: TK2960.F66 2012
subject: Solar cells
subject: Materials science

description: This thesis concerns fabrication of elongated silicon solar cells, together with development and application of supporting characterization techniques. Analysis of J-V curves can reveal considerable detail about recombination in a solar cell. In Chapter 2, the effects of the major recombination mechanisms on the J-V curve are described, taking into account surface, bulk and depletion region. The local ideality factor (m) is derived analytically as a function of operating voltage, and shown to have a value of 2.0, 0.67-0.76, and 1.0 for SRH, Auger and Radiative recombination in high injection respectively. The role of depletion region recombination is discussed. Elongate solar cells are cells that are long (cm), narrow (mm) and thin (tens of microns). The detailed process design and procedure for the fabrication of "plank" elongate silicon solar cells is presented in Chapter 3. Initial batches were tested to have poor open circuit voltage and fill factor which were determined to be caused by pinholes in masking dielectric layers, and dielectric damage caused by laser ablation. Chapter 4 is devoted to characterization of the difference between utilizing a Q-switch Nd:YLF laser or a spindle dicing saw for groove initiation in the formation of plank solar cells. Characterization of the damage was performed using etch rates of the cut, photoluminescence imaging and quasi-steady state photoconductance measurement. Damage recovery etch was also investigated, and it was demonstrated that it is possible to recover above 90% of effective lifetime with sufficient damage etch in a hydroxide etch solution. Due to the position of metal contacts on the edges of elongate solar cells, generated currents have to flow laterally to the edges to be collected. This causes the internal resistance of the device to vary significantly with operating conditions, making it more difficult to quantify accurately. In Chapter 5 the different methods of series resistance (Rs) measurement is reviewed with particular attention to the multi light method due to its ability to accurately measure Rs as a function of voltage. Rs measurements on elongate cells of various emitter sheet resistivity demonstrated that a high emitter sheet resistance causes large Rs variation with operating voltage, and can double between Rs(Voc) to RS(VMPP). It is demonstrated that an Rs-corrected J-V curve can be extracted, which is shown to have good correlation with the Jsc-Voc method. The method of Rs(V) extraction is shown to be generally applicable. In Chapter 6, the developed characterization techniques are applied to determine the causes of fill factor loss in elongate cells.
Risk-based retofit decision model for bridges
Creators: name: Nishimura, Kim S.
Publisher: name: University of British Columbia
Year: 2009

description: A risk-based methodology for making bridge retrofit decisions is demonstrated through a case study of two reinforced concrete highway bridges which were damaged in the Northridge earthquake. An expected value decision model is constructed in order to select the optimal retrofit option for each bridge. The decision alternative which minimizes the total cost of the structure over its life is sought. The total cost includes the initial retrofit cost and the probabilistically predicted future damage cost. Seismic assessments of the Fairfax-Washington and La Cienega-Venice bridges were performed. The seismic hazard at the bridge sites, estimated in terms of intensity and annual probability, was established. The probability of damage was linked to the probability of occurrence of different levels of strong ground motion for a specific site. Inelastic dynamic analyses of the vulnerable bridge components produced estimates of the seismic structural damage for different earthquake intensity levels. These estimates were in the form of damage indices. The damage estimates were then interpreted in terms of dollar losses. Using the hazard information and the damage costs, an expected annual cost of future damages was calculated. Adding the estimated cost of retrofit and the present value of future damages, the total expected cost for each decision alternative was determined. Finally, the sensitivity of the decision model to the input values was investigated. The methodology presented demonstrates rational decision making in the face of inexact or approximate information.
Ground and excited states of spinor Fermi gases in tight waveguides and the Lieb-Liniger-Heisenberg model
Creators: name: Girardeau, M. D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The ground and excited states of a one-dimensional (1D) spin-1/2 Fermi gas (SFG) with both attractive zero-range odd-wave interactions and repulsive zero-range even-wave interactions are mapped exactly to a 1D Lieb-Liniger-Heisenberg (LLH) model with delta-function repulsions depending on isotropic Heisenberg spin-spin interactions, such that the complete SFG and LLH energy spectra are identical. The ground state in the ferromagnetic phase is given exactly by the Lieb-Liniger (LL) Bethe ansatz, and that in the antiferromagnetic phase by a variational method combining Bethe ansatz solutions of the LL and 1D Heisenberg models. There are excitation branches corresponding to LL type I and II phonons and spin waves, the latter behaving quadratically for small wave number in the ferromagnetic phase and linearly in the antiferromagnetic phase.
description: 4 pages, 2 figures, revtex4. To be submitted to Phys. Rev. Lett
Free Field Approach to Solutions of the Quantum Knizhnik-Zamolodchikov Equations
Creators: name: Kuroki, Kazunori
name: Nakayashiki, Atsushi
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 81R10; 17B69

description: Solutions of the qKZ equation associated with the quantum affine algebra $U_q(\hat{sl}_2)$ and its two dimensional evaluation representation are studied. The integral formulae derived from the free field realization of intertwining operators of $q$-Wakimoto modules are shown to coincide with those of Tarasov and Varchenko.
description: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/
Skew Convolution Semigroups and Related Immigration Processes
Creators: name: Li, Zeng-Hu
Publisher: name: arXiv
Year: 2006
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60J80

description: A special type of immigration associated with measure-valued branching processes is formulated by using skew convolution semigroups. We give characterization for a general inhomogeneous skew convolution semigroup in terms of probability entrance laws. The related immigration process is constructed by summing up measure-valued paths in the Kuznetsov process determined by an entrance rule. The behavior of the Kuznetsov process is then studied, which provides insights into trajectory structures of the immigration process. Some well-known results on excessive measures are formulated in terms of stationary immigration processes.
Topological $s$-wave superconductors driven by electron correlation
Creators: name: Zhu, Huai-Shuang
name: Li, Zhidan
name: Han, Qiang
name: Wang, Z. D.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: It is interesting to ask whether electron interaction can turn a topologically trivial superconductor into a nontrivial one without the presence of spin-obital coupling. In this paper we solve a correlated $s$-wave superconducting model exactly. The variation of the fermion number parity of the superconducting ground state as a function of the electron interaction is calculated and the topological phase diagram is obtained. Topological $s$-wave superconducting states are revealed in the doped Mott insulators, which is further confirmed by the numerical investigation of the topological boundary zero mode.
description: 6 pages, 4 figures
An Active Gain-control System for Avalanche Photo-Diodes under Moderate Temperature Variations
Creators: name: Kataoka, J.
name: Sato, R.
name: Ikagawa, T.
name: Kotoku, J.
name: Kuramoto, Y.
name: Tsubuku, Y.
name: Saito, T.
name: Yatsu, Y.
name: Kawai, N.
name: Ishikawa, Y.
name: Kawabata, N.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Avalanche photodiodes (APDs) are promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5x5 mm^2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of DT = 20deg, within a time-cycle of 6000 sec. The best FWHM energy resolution of 6.1+-0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20deg - 0deg cycles. The corresponding values for -20deg - 0deg cycles were 6.9+-0.2 % and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time.
description: 14 pages, 10 figures, accepted by NIM-A
Geometry of all supersymmetric four-dimensional ${\cal N}=1$ supergravity backgrounds
Creators: name: Gran, U.
name: Gutowski, J.
name: Papadopoulos, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We solve the Killing spinor equations of ${\cal N}=1$ supergravity, with four supercharges, coupled to any number of vector and scalar multiplets in all cases. We find that backgrounds with N=1 supersymmetry admit a null, integrable, Killing vector field. There are two classes of N=2 backgrounds. The spacetime in the first class admits a parallel null vector field and so it is a pp-wave. The spacetime of the other class admits three Killing vector fields, and a vector field that commutes with the three Killing directions. These backgrounds are of cohomogeneity one with homogenous sections either $\bR^{2,1}$ or $AdS_3$ and have an interpretation as domain walls. The N=3 backgrounds are locally maximally supersymmetric. There are N=3 backgrounds which arise as discrete identifications of maximally supersymmetric ones. The maximally supersymmetric backgrounds are locally isometric to either $\bR^{3,1}$ or $AdS_4$.
description: 15 pages; minor changes, references added, published version
Construction of Immigration Superprocesses with Dependent Spatial Motion from One-Dimensional Excursions
Creators: name: Dawson, Donald A.
name: Li, Zenghu
Publisher: name: arXiv
Year: 2006
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: A superprocess with dependent spatial motion and interactive immigration is constructed as the pathwise unique solution of a stochastic integral equation carried by a stochastic flow and driven by Poisson processes of one-dimensional excursions.
Tomographic test of Bell's inequality for a time-delocalized single photon
Creators: name: D'Angelo, Milena
name: Zavatta, Alessandro
name: Parigi, Valentina
name: Bellini, Marco
Publisher: name: arXiv
Year: 2006
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Time-domain balanced homodyne detection is performed on two well-separated temporal modes sharing a single photon. The reconstructed density matrix of the two-mode system is used to prove and quantify its entangled nature, while the Wigner function is employed for an innovative tomographic test of Bell's inequality based on the theoretical proposal by Banaszek and Wodkiewicz [Phys. Rev. Lett. 82, 2009 (1999)]. Provided some auxiliary assumptions are made, a clear violation of Banaszek-Bell's inequality is found.
description: 7 pages, 3 figures: revised version with additional material; accepetd for publication in Phys. Rev. A
Semi-classical approach for Anosov diffeomorphisms and Ruelle resonances
Creators: name: Faure, Frederic
name: Roy, Nicolas
name: Sjoestrand, Johannes
Publisher: name: arXiv
Year: 2008
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: In this paper, we show that some spectral properties of Anosov diffeomorphisms can be obtained by semi-classical analysis. In particular the Ruelle resonances which are eigenvalues of the Ruelle transfer operator acting in suitable anisotropic Sobolev spaces and which govern the decay of dynamical correlations, can be treated as the quantum resonances of open quantum systems in the Aguilar-Baslev-Combes theory or the more recent Helffer-Sjostrand phase-space theory.
description: 48 pages
Multipurpose and Reusable Ultrathin Electronic Tattoos Based on PtSe2 and PtTe2
Creators: name: Kireev, Dmitry
name: Okogbue, Emmanuel
name: RT, Jayanth
name: Ko, Tae-Jun
name: Jung, Yeonwoong
name: Akinwande, Deji
Publisher: name: arXiv
Year: 2020
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Wearable bioelectronics with emphasis on the research and development of advanced person-oriented biomedical devices have attracted immense interest in the last decade. Scientists and clinicians find it essential to utilize skin-worn smart tattoos for on-demand and ambulatory monitoring of an individual's vital signs. Here we report on the development of novel ultrathin platinum-based two-dimensional dichalcogenide (Pt-TMDs) based electronic tattoos as advanced building blocks of future wearable bioelectronics. We made these ultrathin electronic tattoos out of large-scale synthesized platinum diselenide (PtSe2) and platinum ditelluride (PtTe2) layered materials and used them for monitoring human physiological vital signs, such as the electrical activity of the heart and the brain, muscle contractions, eye movements, and temperature. We show that both materials can be used for these applications; yet, PtTe2 was found to be the most suitable choice due to its metallic structure. In terms of sheet resistance, skin-contact, and electrochemical impedance, PtTe2 outperforms state-of-the-art gold and graphene electronic tattoos and performs on par with medical-grade Ag/AgCl gel electrodes. The PtTe2 tattoos show four times lower impedance and almost 100 times lower sheet resistance compared to monolayer graphene tattoos. One of the possible prompt implications of the work is perhaps in the development of advanced human-machine interfaces. To display the application, we built a multi-tattoo system that can easily distinguish eye movement and identify the direction of an individual's sight.
Generalized Mehler Semigroups and Catalytic Branching Processes with Immigration
Creators: name: Dawson, Donald A.
name: Li, Zenghu
name: Schmuland, Byron
name: Sun, Wei
Publisher: name: arXiv
Year: 2006
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: Skew convolution semigroups play an important role in the study of generalized Mehler semigroups and Ornstein-Uhlenbeck processes. We give a characterization for a general skew convolution semigroup on real separable Hilbert space whose characteristic functional is not necessarily differentiable at the initial time. A connection between this subject and catalytic branching superprocesses is established through fluctuation limits, providing a rich class of non-differentiable skew convolution semigroups. Path regularity of the corresponding generalized Ornstein-Uhlenbeck processes in different topologies is also discussed.
Comparing conserved charge fluctuations from lattice QCD to HRG model calculations
Creators: name: Goswami, Jishnu
name: Karsch, Frithjof
name: Schmidt, Christian
name: Mukherjee, Swagato
name: Petreczky, Peter
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present results from lattice QCD calculations for $2^{nd}$ and $4^{th}$ order cumulants of conserved charge fluctuations and correlations, and compare these with various HRG model calculations. We show that differences between HRG and QCD calculations already show up in the second order cumulants close to the pseudo-critical temperature for the chiral transition in (2+1)-flavor QCD and quickly grow large at higher temperatures. We also show that QCD results for strangeness fluctuations are enhanced over HRG model calculations which are based only on particles listed in the Particle Data Group tables as 3-star resonances. This suggests the importance of contributions from additional strange hadron resonances. We furthermore argue that additional (repulsive) interactions, introduced either through excluded volume (mean field) HRG models or the S-matrix approach, do not improve the quantitative agreement with $2^{nd}$ and $4^{th}$ order cumulants calculated in lattice QCD. HRG based approaches fail to describe the thermodynamics of strongly interacting matter at or shortly above the pseudo-critical temperature of QCD.
description: 11 pages, 11 figures, Prepared for the proceedings of workshop on Criticality in QCD and the Hadron Resonance Gas; 29-31 July 2020, Wroclaw, Poland
Gap-opening transition in Dirac semimetal ZrTe$_5$
Creators: name: Tian, Yefan
name: Ghassemi, Nader
name: Ross, Joseph H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We apply $^{125}$Te nuclear magnetic resonance (NMR) spectroscopy to investigate the Dirac semimetal ZrTe$_5$. With the NMR magnetic field parallel to the $b$-axis, we observe significant quantum magnetic effects. These include an abrupt drop at 150 K in spin-lattice relaxation rate. This corresponds to a gap-opening transition in the Dirac carriers, likely indicating the onset of excitonic pairing. Below 50 K, we see a more negative shift for the Te$_z$ bridging site indicating the repopulation of Dirac levels with spin polarized carriers at these temperatures. This is the previously reported 3D quantum Hall regime; however, we see no sign of a charge density wave as has been proposed.
description: 5 pages, 4 figures
Absence of superdiffusion in the quasiperiodic spin chain at weak integrability breaking
Creators: name: Znidaric, Marko
Publisher: name: arXiv
Year: 2020
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: There has been interest in the spin transport properties of the Aubry-Andre-Harper model at high temperatures under weak integrability breaking, in particular for small interactions or small fields. We present old unpublished and new results that show that the model is diffusive, meaning that the claimed superdiffusion [1,2] is a finite-size effect.
title: Über die Bewegung kontrahierter Lichtbögen in Vakuumschaltröhren
Creators: name: Janssen, Henning
Publisher: name: UNSPECIFIED
Year: 2021

description: Die Vakuumschalttechnik wird in der Mittelspannungsebene der elektrischen Energieversorgung als die Standardtechnologie eingesetzt. Die plasmaphysikalischen Gesetzmäßigkeiten zum Verhalten eines Lichtbogens während eines Ausschaltstromes wurden ausführlich an Modellanordnungen untersucht und bilden die Grundlagen für die Entwicklung der Vakuumschaltröhren. So ist die Bewegung von rotierenden kontrahierten Lichtbögen mit Hochgeschwindigkeitskameras mithilfe von Einblickfenstern aufgenommen und analysiert worden. Es wurden bis jetzt jedoch keine vergleichenden Untersuchungen zur Lichtbogenbewegung in unterschiedlichen konventionellen Vakuumschaltröhren durchgeführt, die üblicherweise ein intransparentes Gehäuse besitzen. Im Rahmen dieser Arbeit wird ein neuartiges Messverfahren verwendet, das nichtinvasiv mit Hall-Sensoren die magnetischen Felder aufnimmt und dadurch trotz opaker Isolierkeramik und Dampfschirm auf das Bewegungsverhalten des Lichtbogens schließen lässt. Sowohl mit Simulationen als auch Messungen wurde untersucht, dass höher leitfähige Dampfschirmmaterialien die zu messenden Magnetfelder in stärkerem Maße dämpfen. Es wird gezeigt, dass der Lichtbogen bei Spiralarmkontakten sich gegenüber Radial-Magnetfeld-(RMF-)Topfkontakten schneller bewegt, was sich jedoch mit fortschreitendem Alter der Schaltkontakte umkehrt, da der Lichtbogen die Magnetfeld erzeugende Kontaktformen unterschiedlich stark beeinflusst. Eine neue Erkenntnis ist zudem, dass das die Kontakte umgebende Gehäuse der Vakuumschaltröhre einen Einfluss auf die Lichtbogenbewegung ausübt. In engeren Gehäusen kann temporär eine höhere Dampfdichte erzeugt werden. Dadurch kann der Lichtbogen sich schneller bewegen, da sich das Entladungsplasma nicht ausschließlich aus neuem Kontaktmaterial speisen muss. Außerdem wurde der Einfluss von Wirbelströmen im Dampfschirm auf die Lichtbogenbewegung selber diskutiert. All diese Aspekte konnten in bisherigen Modellschaltern nicht untersucht werden.
Qualitative and quantitative assessment of the impact of cryopreservation on human bone marrow-derived mesenchymal stem cells
Creators: name: Soukaina Bahsoun
Publisher: name: Loughborough University
Year: 2021
Subjects: subject: 119999 Medical and Health Sciences not elsewhere classified
subject: FOS: Other medical sciences

description: Regenerative Medicine is currently one of the most active areas of research in public health. Human bone marrow-Mesenchymal Stem Cells (hBM-MSCs) are viewed as a primary tool for the cell therapy and regenerative medicine industries. However, the translation from “bench to bedside” still requires a reliable cell preservation method that does not affect cell identity, viability and before all cell functions. Cryopreservation of hBM-MSCsis addressed in this project. [Continues.]
tau Decays to Five Mesons in TAUOLA
Creators: name: Kuhn, Johann H.
name: Was, Z.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The tau-decay library TAUOLA has gained popularity over the last decade. However, with the continuously increasing precision of the data, some of its functionality has become insufficient. One of the requirements is the implementation of decays into five mesons plus a neutrino with a realistic decay amplitude. This note describes a step into this direction. For the 2pi- pi+ 2pi0 mode the three decay chains tau- --> a_1- nu --> rho- (--> pi- pi0) omega (--> pi- pi+ pi0) nu, tau- --> a_1- nu --> a_1- (--> 2pi- pi+) f_0 (--> 2pi0) nu, and tau- --> a_1- nu --> a_1- (--> pi- 2pi0) f_0 (--> pi + pi-) nu are introduced with simple assumptions about the couplings and propagators of the various resonances. Similar amplitudes (without the rho omega contributions) are adopted for the pi- 4pi0 and 3pi- 2pi+ modes. The five-pion amplitude is thus based on a simple model, which, however, can be considered as a first realistic example. Phase-space generation includes the possibility of presampling the omega and a_1 resonances, in one channel only, however. This is probably sufficient for the time being, both for physics applications and for tests. The technical test of the new part of the generator is performed by comparing Monte Carlo and analytical results. To this end a non-realistic, but easy to calculate, purely scalar amplitude for the decay into five massless pions was used.
description: 10 pages