Publications (42)
YSE-PZ: A Transient Survey Management Platform that Empowers the Human-in-the-Loop
D. A. Coulter, D. O. Jones, P. McGill +19
The modern study of astrophysical transients has been transformed by an exponentially growing volume of data. Within the last decade, the transient discovery rate has increased by…
Fluctuation theorem for entropy production during effusion of a relativistic ideal gas
B. Cleuren, K. Willaert, A. Engel +1
The probability distribution of the entropy production for the effusion of a relativistic ideal gas is calculated explicitly. This result is then extended to include particle and a…
Cylindrical Korteweg-de Vries solitons on a ferrofluid surface
D. Rannacher, A. Engel
Linear and non-linear surface waves on a ferrofluid cylinder surrounding a current-carrying wire are investigated. Suppressing the Rayleigh-Plateau instability of the fluid column…
On the VC-dimension of neural networks with binary weights
S. Mertens, A. Engel
We investigate the VC-dimension of the perceptron and simple two-layer networks like the committee- and the parity-machine with weights restricted to values . For binary inpu…
Symbiotic Optimization of the Nanolithography and RF-Plasma Etching for Fabricating High-Quality Light-Sensitive Superconductors on the 50 nm Scale
H. Bartolf, K. Inderbitzin, L. B. Gómez +6
We present results of a fabrication-process development for the lithographic pattern transfer into the sub-100nm range by combining electron-beam lithography and reactive dry etchi…
Current Assisted, Thermally Activated Flux Liberation in Ultrathin Nanopatterned NbN Superconducting Meander Structures
H. Bartolf, A. Engel, A. Schilling +4
We present results from an extensive study of fluctuation phenomena in superconducting nanowires made from sputtered NbN. Nanoscale wires were fabricated in form of a meander and o…
Asymptotics of work distributions: The pre-exponential factor
D. Nickelsen, A. Engel
We determine the complete asymptotic behaviour of the work distribution in driven stochastic systems described by Langevin equations. Special emphasis is put on the calculation of…
Shape transformations in rotating ferrofluid drops
K. I. Morozov, A. Engel, A. V. Lebedev
Floating drops of magnetic fluid can be brought into rotation by applying a rotating magnetic field. We report theoretical and experimental results on the transition from a spheroi…
Comment on "Invalidation of the Kelvin Force in Ferrofluids"
A. Engel
It is shown that the experimental results reported in cond-mat/0010412 do not invalidate the well-known expression for the Kelvin force density in ferrofluids.
Multifractal Analysis of the Coupling Space of Feed-Forward Neural Networks
A. Engel, M. Weigt
Random input patterns induce a partition of the coupling space of feed-forward neural networks into different cells according to the generated output sequence. For the perceptron t…
Rolling ferrofluid drop on the surface of a liquid
V. Sterr, R. Krauss, K. I. Morozov +3
We report on the controlled transport of drops of magnetic liquid, which are swimming on top of a non-magnetic liquid layer. A magnetic field which is rotating in a vertical plane…
A multifractal phase-space analysis of perceptrons with biased patterns
J. Berg, A. Engel
We calculate the multifractal spectrum of the partition of the coupling space of a perceptron induced by random input-output pairs with non-zero mean. From the results we infer the…
Planform selection in two-layer Benard-Marangoni convection
A. Engel, J. B. Swift
Benard-Marangoni convection in a system of two superimposed liquids is investigated theoretically. Extending previous studies the complete hydrodynamics of both layers is treated a…
Fingering Instability in a Water-Sand Mixture
A. Lange, M. Schröter, M. A. Scherer +2
The temporal evolution of a water-sand interface driven by gravity is experimentally investigated. By means of a Fourier analysis of the evolving interface the growth rates are det…
Dilepton Production in Nucleon-Nucleon Interactions
M. Schäfer, H. C. Dönges, A. Engel +1
Starting from a realistic one--boson--exchange--model fitted to the amplitudes of elastic nucleon--nucleon scattering and the process we perform a fully relativ…
On the electromagnetic force on a polarizable body
A. Engel, R. Friedrichs
The force on a macroscopic polarizable body in an inhomogenous electromagnetic field is calculated for three simple exactly solvable situations. Comparing different approaches we p…
Characteristics of superconducting tungsten silicide WxSi1-x for single photon detection
X. Zhang, A. Engel, Q. Wang +7
Superconducting properties of three series of amorphous WxSi1-x films with different thickness and stoichiometry were investigated by dc transport measurements in a magnetic field…
Magnetic-field dependence of count rates in superconducting thin-film TaN single-photon detectors
A. Engel, A. Schilling, K. Il'in +1
We have studied the magnetic-field dependence of both dark-count rates and photon-count rates in a superconducting nanowire single-photon detector made of TaN in external magnetic…
Probing small-scale intermittency with a fluctuation theorem
D. Nickelsen, A. Engel
We characterize statistical properties of the flow field in developed turbulence using concepts from stochastic thermodynamics. On the basis of data from a free air-jet experiment,…
K^+ momentum spectrum from (K^-,K^+) reactions in intranuclear cascade model
Y. Nara, A. Ohnishi, T. Harada +1
In a framework of intranuclear cascade (INC) type calculation, we study a momentum spectrum in reactions \KK at a beam momentum of 1.65 GeV/c. INC model calculations are compared w…
The Young Supernova Experiment: Survey Goals, Overview, and Operations
D. O. Jones, R. J. Foley, G. Narayan +68
Time domain science has undergone a revolution over the past decade, with tens of thousands of new supernovae (SNe) discovered each year. However, several observational domains, in…
Matrix Games, Mixed Strategies, and Statistical Mechanics
J. Berg, A. Engel
Matrix games constitute a fundamental problem of game theory and describe a situation of two players with completely conflicting interests. We show how methods from statistical mec…
Pion production in proton-proton collisions in a covariant one boson exchange model
A. Engel, A. K. Dutt-Mazumder, R. Shyam +1
Motivated by the renewed interest in studying the pion production on nuclei with protons at few GeV incident energies, we investigate the pion production in proton-proton collision…
Replica theory for Levy spin glasses
K. Janzen, A. K. Hartmann, A. Engel
Infinite-range spin-glass models with Levy-distributed interactions show a spin-glass transition with similarities to both the Sherrington-Kirkpatrick model and to disordered spin…
Asymptotic work distributions in driven bistable systems
D. Nickelsen, A. Engel
The asymptotic tails of the probability distributions of thermodynamic quantities convey important information about the physics of nanoscopic systems driven out of equilibrium. We…
Thermodynamics of the Lévy spin glass
K. Janzen, A. Engel, M. Mézard
We investigate the Lévy glass, a mean-field spin glass model with power-law distributed couplings characterized by a divergent second moment. By combining extensively many small c…
Multifractality and percolation in the coupling space of perceptrons
M. Weigt, A. Engel
The coupling space of perceptrons with continuous as well as with binary weights gets partitioned into a disordered multifractal by a set of random input patterns. The mult…
Pion and Eta Photoproduction in Nuclei
A. Hombach, A. Engel, S. Teis +1
We calculate the quasifree photoproduction of pions and eta mesons on nuclei from 12C to 208Pb. Assuming that for the quasifree process the cross sections for pi/eta - photoproduct…
The Levy spin glass transition
K. Janzen, A. Engel, M. Mézard
We determine the phase transition of the Levy spin glass. A regularized model where the coupling constants smaller than some cutoff are neglected can be studied by the cavity…
Pion-nucleus reactions in a microscopic transport model
A. Engel, W. Cassing, U. Mosel +2
We analyse pion-nucleus reactions in a microscopic transport model of the BUU type, which propagates nucleons, pions, deltas and N(1440)-resonances explicitly in space and time. In…
Vortex dynamics in layered superconductors with correlated defects: influence of interlayer coupling
A. Engel, H. J. Trodahl, J. C. Abele +2
We report a detailed study of the vortex dynamics and vortex phase diagrams of two amorphous Ta_0.3Ge_0.7/Ge multilayered films with intrinsic coplanar defects, but different inter…
Storage capacity of correlated perceptrons
D. Malzahn, A. Engel, I. Kanter
We consider an ensemble of single-layer perceptrons exposed to random inputs and investigate the conditions under which the couplings of these perceptrons can be chosen such th…
Superconductivity in the ferromagnetic semiconductor SmN
E. -M. Anton, S. Granville, A. Engel +8
The discovery of materials that simultaneously host different phases of matter has often initially confounded, but ultimately enhanced, our basic understanding of the coexisting ty…
The Young Supernova Experiment Data Release 1 (YSE DR1): Light Curves and Photometric Classification of 1975 Supernovae
P. D. Aleo, K. Malanchev, S. Sharief +80
We present the Young Supernova Experiment Data Release 1 (YSE DR1), comprised of processed multi-color Pan-STARRS1 (PS1) griz and Zwicky Transient Facility (ZTF) gr photometry of 1…
Nanoscale Fabrication by Intrinsic Suppression of Proximity-Electron Exposures and General Considerations for Easy & Effective Top-Down Fabrication
H. Bartolf, K. Inderbitzin, L. B. Gómez +2
We present results of a planar process development based on the combination of electron-beam lithography and dry etching for fabricating high-quality superconducting photosensitive…
Suppressing the Rayleigh-Taylor instability with a rotating magnetic field
D. Rannacher, A. Engel
The Rayleigh-Taylor instability of a magnetic fluid superimposed on a non-magnetic liquid of lower density may be suppressed with the help of a spatially homogeneous magnetic field…
Asymptotics of work distributions in non-equilibrium systems
A. Engel
The asymptotic behaviour of the work probability distribution in driven non-equilibrium systems is determined using the method of optimal fluctuations. For systems described by Lan…
Fluctuation effects in superconducting nanostrips
A. Engel, A. D. Semenov, H. -W. Huebers +2
Superconducting fluctuations in long and narrow strips made from ultrathin NbN films, have been investigated. For large bias currents close to the critical current fluctuations led…
Replica mean-field theory for Levy spin-glasses
A. Engel
Infinite-range spin-glass models with Levy-distributed interactions show a freezing transition similar to disordered spin systems on finite connectivity random graphs. It is shown…
Correlations between hidden units in multilayer neural networks and replica symmetry breaking
D. Malzahn, A. Engel
We consider feed-forward neural networks with one hidden layer, tree architecture and a fixed hidden-to-output Boolean function. Focusing on the saturation limit of the storage pro…
Jarzynski equation for a simple quantum system: Comparing two definitions of work
A. Engel, R. Nolte
The validity of the Jarzynski equation for a very simple, exactly solvable quantum system is analyzed. The implications of two different definitions of work proposed in the literat…
Production of Eta-Mesons in Collisions of Nucleons and Delta-Resonances
W. Peters, U. Mosel, A. Engel
We calculate the cross section for the production of -mesons via \mbox{} in a relativistic One-Boson-Exchange-Model. Using this cross section we then determine…