Injection of energetic particles following the gamma-ray flares on June 7, 1980, as observed on Helios 1

On June 7, 1980, two flares with impulsive gamma-ray emission were observed at 0117 Ut and 0312 UT. Measurements of the University of Kiel cosmic-ray experiment on HELIOS-1 are presented. The first approx. 0.5 MeV electrons escaped from the Sun to interplanetary space simultaneously with the hard X-ray burst. For the 0312 UT flare the protons and alpha-particle in the 3 - 20 MeV/nucleon range were injected from the Sun with a delay of approx. 40 min, followed by two subsequent new emissions

Optical waveguides with compound multiperiodic grating nanostructures for refractive index sensing

The spectral characteristics and refractive index sensitivity of compound multiperiodic grating waveguides are investigated in theory and experiment. Compound gratings are formed by superposition of two or more monoperiodic gratings. Compared to monoperiodic photonic crystal waveguides, compound grating waveguides offer more degrees of design freedom by choice of component grating periods and duty cycles. Refractive index sensing is achieved by evaluating the wavelength or intensity of guided mode resonances in the reflection spectrum. We designed, fabricated, and characterized 24 different compound multiperiodic nanostructured waveguides for refractive index sensing. Simulations are carried out with the Rigorous Coupled Wave Algorithm (RCWA). The resulting spectra, resonance sensitivities, and quality factors are compared to monoperiodic as well as to three selected aperiodic nanostructures (Rudin-Shapiro, Fibonacci, and Thue-Morse). The refractive index sensitivity of the TE resonances is similar for all types of investigated nanostructures. For the TM resonances the compound multiperiodic nanostructures exhibit higher sensitivity values compared to the monoperiodic nanostructure and similar values as the aperiodic nanostructures. No significant influence of the compound grating duty cycles on the sensitivity is observed

Onleihe-Verbünde - Anregungen für eine landesweite Verbundstrategie in NRW

Die vorliegende Bachelorarbeit beschäftigt sich mit der Entwicklung von Anregungen für eine landesweite Verbundstrategie für die Onleihen an Öffentlichen Bibliotheken in Nordrhein-Westfalen. Dabei wird in einer Analyse der Ausgangssituation ein Überblick über die aktuellen Organisationen und Herausforderungen der Onleihe-Verbünde und Einzel-Onleihen in NRW sowie deren Vorstellungen zu einem Landesverbund gegeben. Anschließend werden in einer Umfeldanalyse die drei landesweiten Onleihe-Verbünde in Hessen, Niedersachsen und Mecklenburg-Vorpommern vorgestellt. Es wird dabei auf ihre zentralen Organisationsstrukturen und Vorschläge für eine Verbundzusammenführung in NRW eingegangen. Den Abschluss bildet die Entwicklung eines strategischen Konzeptansatzes für einen Landesverbund in Nordrhein-Westfalen.This bachelor's thesis deals with the development of suggestions for a nationwide consortium strategy for e-lending at public libraries in NRW. An analysis of the current situation provides an overview of the existing organizations and challenges of the e-lending associations and individual e-lending in NRW, as well as their ideas about a state-wide association. Following this, an environmental analysis presents the three state-wide e-lending consortia in Hesse, Lower Saxony, and Mecklenburg-Vorpommern. The focus is on their central organizational structures and proposals for merging consortia in NRW. The thesis concludes with the development of a strategic concept approach for a state-wide association in NRW

TIMASSS: The IRAS16293-2422 Millimeter And Submillimeter Spectral Survey. I. Observations, calibration and analysis of the line kinematics

While unbiased surveys observable from ground-based telescopes have previously been obtained towards several high mass protostars, very little exists on low mass protostars. To fill up this gap, we carried out a complete spectral survey of the bands at 3, 2, 1 and 0.8 mm towards the solar type protostar IRAS16293-2422. The observations covered about 200\,GHz and were obtained with the IRAM-30m and JCMT-15m telescopes. Particular attention was devoted to the inter-calibration of the obtained spectra with previous observations. All the lines detected with more than 3 sigma and free from obvious blending effects were fitted with Gaussians to estimate their basic kinematic properties. More than 4000 lines were detected (with sigma \geq 3) and identified, yielding a line density of approximatively 20 lines per GHz, comparable to previous surveys in massive hot cores. The vast majority (~2/3) of the lines are weak and due to complex organic molecules. The analysis of the profiles of more than 1000 lines belonging 70 species firmly establishes the presence of two distinct velocity components, associated with the two objects, A and B, forming the IRAS16293-2422 binary system. In the source A, the line widths of several species increase with the upper level energy of the transition, a behavior compatible with gas infalling towards a ~1 Mo object. The source B, which does not show this effect, might have a much lower central mass of ~0.1 Mo. The difference in the rest velocities of both objects is consistent with the hypothesis that the source B rotates around the source A. This spectral survey, although obtained with single-dish telescope with a low spatial resolution, allows to separate the emission from 2 different components, thanks to the large number of lines detected. The data of the survey are public and can be retrieved on the web site http://www-laog.obs.ujf-grenoble.fr/heberges/timasss.Comment: 41 pages (26 pages of online Tables), 7 Tables and 6 Figure

Raman and infrared spectra of dimethyl ether 13C-isotopologue (CH3O13CH3) from a CCSD(T) potential energy surface

So far, no experimental data of the infrared and Raman spectra of 13C isotopologue of dimethyl ether are available. With the aim of providing some clues of its low-lying vibrational bands and with the hope of contributing in a next spectral analysis, a number of vibrational transition frequencies below 300 cm−1 of the infrared spectrum and around 400 cm−1 of the Raman spectrum have been predicted and their assignments were proposed. Calculations were carried out through an ab initio three dimensional potential energy surface based on a previously reported one for the most abundant dimethyl ether isotopologue (M. Villa et al., J. Phys. Chem. A 115 (2011) 13573). The potential function was vibrationally corrected and computed with a highly correlated CCSD(T) method involving the COC bending angle and the two large amplitude CH3 internal rotation degrees of freedom. Also, the Hamiltonian parameters could represent a support for the spectral characterization of this species. Although the computed vibrational term values are expected to be very accurate, an empirical adjustment of the Hamiltonian has been performed with the purpose of anticipating some workable corrections to any possible divergence of the vibrational frequencies. Also, the symmetry breaking derived from the isotopic substitution of 13C in the dimethyl ether was taken into account when the symmetrization procedure was applied

Simulation Methods for Multiperiodic and Aperiodic Nanostructured Dielectric Waveguides

Nanostructured dielectric waveguides are of high interest for biosensing applications, light emitting devices as well as solar cells. Multiperiodic and aperiodic nanostructures allow for custom-designed spectral properties as well as near-field characteristics with localized modes [1-4]. Here, a comparison of experimental results and simulation results obtained with different simulation methods is presented. We fabricated and characterized multiperiodic nanostructured dielectric waveguides with two, three, and four compound grating periods as well as aperiodic nanostructured waveguides based on Rudin-Shapiro, Fibonacci, and Thue-Morse binary sequences. The near-field and far-field properties are calculated employing the finite-element method (FEM), the finite- difference time-domain (FDTD) method as well as a rigorous coupled wave algorithm (RCWA). References[1] S. V. Boriskina, A. Gopinath, L. Dal Negro, Optical gap formation and localization properties of optical modes in deterministic aperiodic photonic structures, Opt. Express 16, 18813, 2008[2] E. Maciá, Exploiting aperiodic designs in nanophotonic devices, Rep Prog Phys 75, 036502,2012[3] C. Kluge, J. Adam, N. Barié, P. J. Jakobs, M. Guttmann, M. Gerken, Multiperiodic nanostructuresfor photon control, Opt. Express 22, A1363-A1371, 2014[4] L. T. Neustock, S. Jahns, J. Adam, M. Gerken, Optical waveguides with compound grating nanostructures for refractive index sensing, J. of Sensors, 6174527, 201

Properties of Deterministic Aperiodic Photonic Nanostructures for Biosensors

Periodic dielectric photonic nanostructures have been used extensively as transducers in refractive index sensors. Photonic crystal slabs exhibit sharp resonances in the transmission and reflection spectrum. Changes in resonance wavelength, intensity, or quality factor are measured to monitor changes in the analyte region on top of the structure [1]. By specific biofunctionalization of the crystal surface, specific molecule capture is achieved. We demonstrated a handheld intensity-based measurement setup that allows for imaging detection of binding events at the surface [1]. To enhance the sensitivity of such systems, the use of deterministic aperiodic nanostructures (DANS) has been suggested [2-4]. DANS are engineered ordered nanostructures without periodicity [2,3]. The additional degrees of freedom allow for a tailoring of the optical properties. Boriskina et al. calculated that quasi-localized critical modes in aperiodic nanostructures simultaneously exhibit high quality factors Q und high sensitivity S to refractive index changes [2]. We previously calculated the spectral response of different DANS [4]. Here, we present experimental results for DANS devices (Thue- Morse, Fibonacci, Rudin-Shapiro) consisting of a nanoimprinted photo mold layer providing the nanostructure and a TiO2 high index layer (fig. 1). The measured characteristics (band diagram, far field) of these devices are compared to the ones of mono- and multiperiodic nanostructures. Near-field and far-field calculations are carried out for these structures and are compared to the experimental results.[1] Jahns, S., Bräu, M., Meyer, B. O., Karrock, T., Gutekunst, S. B., Blohm, L., Selhuber-Unkel, C., Buhmann, R., Nazirizadeh, Y., Gerken, M. (2015). Handheld imaging photonic crystal biosensor for multiplexed, label-free protein detection. Biomedical Optics Express, 6(10), 3724-3736.[2] Boriskina, S. V., Dal Negro, L. (2008). Sensitive label-free biosensing using critical modes in aperiodic photonic structures. Optics Express, 16(17), 12511-12522.[3] Dal Negro, L., Boriskina, S. V. (2012). Deterministic aperiodic anostructures for photonics and plasmonics applications. Laser and Photonics Reviews, 6(2), 178-218.[4] Neustock, L. T., Jahns, S., Adam, J., Gerken, M. (2016). Optical waveguides with compound multiperiodic grating nanostructures for refractive index sensing. Journal of Sensors, 501, 6174527

Simulation Methods for Multiperiodic and Aperiodic Nanostructured Dielectric Waveguides

Nanostructured dielectric waveguides are of high interest for biosensing applications, light emitting devices as well as solar cells. Multiperiodic and aperiodic nanostructures allow for custom-designed spectral properties as well as near-field characteristics with localized modes [1-4]. Here, a comparison of experimental results and simulation results obtained with different simulation methods is presented. We fabricated and characterized multiperiodic nanostructured dielectric waveguides with two, three, and four compound grating periods as well as aperiodic nanostructured waveguides based on Rudin-Shapiro, Fibonacci, and Thue-Morse binary sequences. The near-field and far-field properties are calculated employing the finite-element method (FEM), the finite- difference time-domain (FDTD) method as well as a rigorous coupled wave algorithm (RCWA). References[1] S. V. Boriskina, A. Gopinath, L. Dal Negro, Optical gap formation and localization properties of optical modes in deterministic aperiodic photonic structures, Opt. Express 16, 18813, 2008[2] E. Maciá, Exploiting aperiodic designs in nanophotonic devices, Rep Prog Phys 75, 036502,2012[3] C. Kluge, J. Adam, N. Barié, P. J. Jakobs, M. Guttmann, M. Gerken, Multiperiodic nanostructuresfor photon control, Opt. Express 22, A1363-A1371, 2014[4] L. T. Neustock, S. Jahns, J. Adam, M. Gerken, Optical waveguides with compound grating nanostructures for refractive index sensing, J. of Sensors, 6174527, 201

CCSD(T) Study of CD3-O-CD3 and CH3-O-CD3 Far-Infrared Spectra

From a vibrationally corrected 3D potential energy surface determined with highly correlated ab initio calculations (CCSD(T)), the lowest vibrational energies of two dimethyl-ether isotopologues, 12CH3–16O–12CD3 (DME-d3) and 12CD3–16O–12CD3 (DME-d6), are computed variationally. The levels that can be populated at very low temperatures correspond to the COC-bending and the two methyl torsional modes. Molecular symmetry groups are used for the classification of levels and torsional splittings. DME-d6 belongs to the G36 group, as the most abundant isotopologue 12CH3–16O–12CH3 (DME-h6), while DME-d3 is a G18 species. Previous assignments of experimental Raman and far-infrared spectra are discussed from an effective Hamiltonian obtained after refining the ab initio parameters. Because a good agreement between calculated and experimental transition frequencies is reached, new assignments are proposed for various combination bands corresponding to the two deuterated isotopologues and for the 020 → 030 transition of DME-d6. Vibrationally corrected potential energy barriers, structural parameters, and anharmonic spectroscopic parameters are provided. For the 3N – 9 neglected vibrational modes, harmonic and anharmonic fundamental frequencies are obtained using second-order perturbation theory by means of CCSD and MP2 force fields. Fermi resonances between the COC-bending and the torsional modes modify DME-d3 intensities and the band positions of the torsional overtones

Simulation methods for multiperiodic and aperiodic nanostructured dielectric waveguides

Nanostructured dielectric waveguides are of high interest for biosensing applications, light emitting devices as well as solar cells. Multiperiodic and aperiodic nanostructures allow for custom-designed spectral properties as well as near-field characteristics with localized modes. Here, a comparison of experimental results and simulation results obtained with three different simulation methods is presented. We fabricated and characterized multiperiodic nanostructured dielectric waveguides with two and three compound periods as well as deterministic aperiodic nanostructured waveguides based on Rudin–Shapiro, Fibonacci, and Thue–Morse binary sequences. The near-field and far-field properties are computed employing the finite-element method (FEM), the finite-difference time-domain (FDTD) method as well as a rigorous coupled wave algorithm (RCWA). The results show that all three methods are suitable for the simulation of the above mentioned structures. Only small computational differences are obtained in the near fields and transmission characteristics. For the compound multiperiodic structures the simulations correctly predict the general shape of the experimental transmission spectra with number and magnitude of transmission dips. For the aperiodic nanostructures the agreement between simulations and measurements decreases, which we attribute to imperfect fabrication at smaller feature sizes