Alignment-Dependent Ionization of Molecular Hydrogen in Intense Laser Fields

The alignment dependence of the ionization behavior of H$_2$ exposed to intense ultrashort laser pulses is investigated on the basis of solutions of the full time-dependent Schr\"odinger equation within the fixed-nuclei and dipole approximation. The total ionization yields as well as the energy-resolved electron spectra have been calculated for a parallel and a perpendicular orientation of the molecular axis with respect to the polarization axis of linear polarized laser pulses. For most, but not all considered laser peak intensities the parallel aligned molecules are easier to ionize. Furthermore, it is shown that the velocity formulation of the strong-field approximation predicts a simple interference pattern for the ratio of the energy-resolved electron spectra obtained for the two orientations, but this is not confirmed by the full ab initio results.Comment: 4 figure

Ionization of molecular hydrogen and deuterium by a frequency-doubled Ti:sapphire laser pulses

A theoretical study of the intense-field single ionization of molecular hydrogen or deuterium oriented either parallel or perpendicular to a linear polarized laser pulse (400 nm) is performed for different internuclear separations and pulse lengths in an intensity range of $(2-13)\times10^{13}$W cm$^{-2}$. The investigation is based on a non-perturbative treatment that solves the full time-dependent Schr\"odinger equation of both correlated electrons within the fixed-nuclei and the dipole approximation. The results for various internuclear separations are used to obtain the ionization yields of molecular hydrogen and deuterium in their ground vibrational states. An atomic model is used to identify the influence of the intrinsic diatomic two-center character of the problem.Comment: 13 pages, 9 figure

Explicit summation of the constituent WKB series and new approximate wave functions

The independent solutions of the one-dimensional Schr\"odinger equation are approximated by means of the explicit summation of the leading constituent WKB series. The continuous matching of the particular solutions gives the uniformly valid analytical approximation to the wave functions. A detailed numerical verification of the proposed approximation is performed for some exactly solvable problems arising from different kinds of potentials.Comment: 8 pages, LaTeX, minor changes and stylistic improvements, final versio

Laivan paloriski-indeksin kehittäminen

Fire is one of the most common threatening accidents onboard a cruise ship. As cruise ship sizes are growing, as well as the number of passengers onboard, so does the risk in catastrophic accidents. It is widely believed, that larger cruise ships oppose bigger risks. On the other hand, a larger ship has a greater potential to survive accidents and to perform its duty as the best lifeboat itself. Another aspect of growing cruise ship size is that the perception of the overall fire safety level of the ship becomes difficult to assess, and the perception of the risks involved diminishes. From previous points, a need for a tool, which could be used for assessing and comparing holistic fire safety levels of cruise ships, was recognized. In this master’s thesis, a model was developed to quantify the overall fire safety level of a cruise ship in a manner that enables comparison between fire safety levels of other cruise ships. The model is based on the fire risk indexing method. The model consists of three modules: fire safety, evacuation and resilience, which are evaluated and scored independently. These scores are then weighted, and the overall fire safety score of the ship is obtained. Fire safety and the resilience modules function as intended. Finalizing of the evacuation module was left out for future work due to difficulty in assessing embarkation reliably with a method suitable for the model. Some parts of the model should be reassessed and looked into in more depth.Yksi yleisimpiä koko risteilylaivaa uhkaavia onnettomuuksia on tulipalo. Uusien risteilylaivojen koko jatkaa kasvuaan. Kun risteilylaivojen koko kasvaa, niin kasvaa laivalla olevien matkustajien lukumääräkin. Suurempi ihmismäärä laivalla johtaa suurempaan riskiin katastrofaalisessa onnettomuudessa. Yleisesti hyväksytty kanta on, että suurempi risteilylaiva tarkoittaa suurempaa riskiä. Toisaalta suuremmalla risteilylaivalla on suurempi mahdollisuus selviytyä onnettomuudesta ja toimia itsessään parhaana pelastusveneenä, niin kuin on tarkoituskin. Toinen huomionarvoinen asia on, että risteilylaivan koon kasvaessa sen kokonaisvaltaisen palotuvallisuuden käsitteleminen hankaloituu ja siihen liittyvien riskien käsitys hämärtyy. Edellisiin kohtiin perustuen havaittiin tarve työkalulle, jolla voitaisiin arvioida ja verrata risteilylaivojen kokonaisvaltaista paloturvallisuutta. Tämän diplomityön aikana kehitettiin työkalu, jolla voidaan qvantifioida risteilylaivan kokonaisvaltainen paloturvallisuustaso niin, että sitä voidaan verrata muiden vastaavien risteilylaivojen paloturvallisuustasoon. Malli perustuu paloriski-indeksiin. Malli sisältää kolme moduulia, jotka arvioidaan erikseen; paloturvallisuus-, evakuointi- ja selviytymismoduuli. Moduuleista saadut pistemäärät painotetaan merkitsevyyskertoimella ja tuloksena on kokonaisvaltainen paloturvallisuusindeksi. Paloturvallisuus- ja selviytymismoduulit toimivat suunnitellusti. Pelastusveneisiin siirtymisen mallintaminen mallille sopivalla tavalla osoittautui haastavaksi, minkä takia evakuointimoduulin viimeisteleminen jätettiin työn seuraavaan vaiheeseen. Joitakin mallin osia tarvitsee käsitellä tulevaisuudessa tarkemmin uudelleen

Expected operational synergies as a determinant of M&A premium levels and their cyclical changes in time

Purpose of the study Expected synergies are often presented as a motivator to pay high premiums in corporate mergers and acquisition. In the existing literature on the topic, however, there is a distinct dissonance on whether this holds true empirically. Apparently, the inability to agree on the role of expected synergies as a determinant of takeover premiums stems from differing interpretation of synergies as a concept and differing methodologies to measure synergistic value. This paper aims to provide new information to this discussion via three vehicles. First, I narrow the scope from overall synergies and focus merely on operational cost-side synergies to decompose the relationship between premiums and expected synergistic value. Secondly, I introduce differing valuation processes between industries as a possible way to increase prediction power for premiums. Thirdly, I study the premiums’ autocorrelative time-behavior and its dependency on expected operational synergies as an extension to speculative explanations for the premiums’ momentum proposed in extant research. Data and methodology The data set consists of 2,082 European public takeovers between 2006 and 2015, extracted from Mergermarket database. The relationship between takeover premiums and expected operational synergies is tested with simple OLS regressions and subsequent F-tests for testing the joint power of additional variables included in the model, with and without a set of industry classification binaries included. The momentum effect in premiums is confirmed with estimating monthly premium average’s autocorrelation coefficients and testing their significance. Based on these results, an autoregressive moving average model is estimated for two subgroups determined by the assumed existence of expected operational synergies to determine whether changes in expected operational synergies cyclically drive the premiums in time. Findings Takeover premiums are found to be generally independent on expected operational synergies. Also, premium levels significantly differ between industries. The expected operational synergies’ role as a determinant of takeover premiums is found to significantly deviate between industries, but individual industries where the effect would be considerably strong are not identified. Consistently with the existing research, takeover premiums are found to exhibit momentum. Specifically, monthly premium averages are found to be correlated with up to five lagged monthly periods. The time-behavior of premiums is not found to significantly deviate between transactions with and without expected operational synergies. Thus, it is concluded that changes in expected operational synergies do not generally drive takeover premiums

Generalized gauge-invariant formulations of the strong-field approximation

The gauge problem in the so-called strong-field approximation (SFA) describing atomic or molecular systems exposed to intense laser fields is investigated. Introducing a generalized gauge and partitioning of the Hamiltonian it is demonstrated that the S-matrix expansion obtained in the SFA depends on both gauge and partitioning in such a way that two gauges always yield the same S-matrix expansion, if the partitioning is properly chosen.Comment: 11 page

Faktor-faktor yang mempengaruhi kinerja auditor internal perusahaan

This study aims to analyze and explain what factors affect the performance of internal auditors from goods and service procurement companies PT. KAI DAOP 8.. This study uses quantitative methods with a population of 80 internal auditors from goods and service procurement companies PT. KAI DAOP 8. Sampling using simple random sampling technique and obtained a sample of 67 samples. The technique used in this study is multiple linear regression analysis using SPSS software. The results are auditor independence, organizational commitment, understanding of good governance, leadership style, and organizational culture have a significant and positive effect on the performance of the company's internal auditors