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The detailed understanding of the behavior of the electronic states of multielectron atoms and small molecules is fundamental for advancement in a wide variety of fields. The present work aims at deepening this understanding by studying elusive, small cross section processes during photoionization and decay, beyond the dominant well-known processes. The branching ratio and anisotropy parameters of the satellite states accompanying the Kr 3d photoionization line were measured, shedding light on their creation mechanisms, with the support of theoretical results. By utilizing electron coincidence techniques, a method to measure the possibility of interatomic Auger effect in N2O could be illustrated and an upper limit on the probability established. The binding energies of the nitrogen 1s−1v−1 states in N2O were also measured. For this study, a multi-electron coincidence analyzer was developed. Furthermore, the decay of argon 2p−2 double core hole states populated by Auger decay after 1s ionization was studied by measuring electron-ion coincidences. Theoretical calculations allowed the assignment of intermediate and final states. All experiments were carried out at synchrotron facilities., Tiivistelmä Monielektronisten atomien ja pienten molekyylien elektronisten tilojen yksityiskohtainen ymmärtäminen luo pohjaa monien eri alojen kehittymiselle. Tämän työn tavoitteena on edistää tätä ymmärrystä tutkimalla hallitsevien tunnettujen siirtymien sijasta vaikeasti havaittavia, pienen vaikutusalan fotoionisaatioprosesseja ja elektronisten tilojen purkautumisia. Kr 3d -fotoionisaatioviivan satelliittitilojen intensiteettisuhteet ja anisotropiaparametrit mitattiin, ja vertaamalla tuloksia koetta tukeviin teoreettisiin laskuihin saatiin tietoa satelliittitilojen syntymekanismeista. Työssä esitettiin menetelmä atomien välisen Auger-ilmiön todennäköisyyden mittaamiseksi N2O:ssa elektronikoinsidenssitekniikoita käyttäen ja määritettiin prosessin todennäköisyyden yläraja. Myös N2O:n typen 1s−1v−1-tilojen sidosenergiat mitattiin. Tätä tutkimusta varten kehitettiin koinsidenssianalysaattori, jolla voidaan mitata useita elektroneja yhtäaikaisesti. Lisäksi argonin 1s-ionisaation Auger-purkautumisen seurauksena syntyvien 2p−2 sisäkuoren kaksoisaukkotilojen purkautumista tutkittiin mittaamalla elektroni-ioni-koinsidensseja. Teoreettisten laskujen avulla purkautumisprosessin väli- ja lopputiloja pystyttiin tunnistamaan. Väitöstyön kaikki kokeet suoritettiin synkrotronisäteilylaitoksissa.

The interatomic Auger effect following O 1s ionization in N₂O has been experimentally investigated using multi-electron coincidence spectroscopy. The expected transition energies have been established by comparison to the measured N 1s⁻¹v⁻¹ core-valence double ionization energies. We describe a procedure to eliminate the background of two competing processes contributing spectroscopic signatures to the same energy range, namely double Auger decay of the O 1s vacancy and direct single-photon double ionization into the N 1s⁻¹v⁻¹ states. While the interatomic Auger transitions could not be successfully isolated, we provide an upper boundary of the transition probability of 0.07% with respect to the dominant single Auger decay after O 1s ionization.

The study was concerned with the conceptual design and evaluation of military heavy logistics transport aircraft entering service in the 1990-2000 time period. Design paylaods of 200,000-600,000 lb. and design ranges of 3600-7200 nm were considered. Takeoff field length was 8000 ft. in most cases. Suitability for commercial usage was a major objective. Computer aided design techniques were employed extensively for airplane synthesis and analysis. The study was accomplished in two phases. Phase I included parametric design and analysis of transports in the payload/range categories cited above. An advanced technology review, including evaluations and sensitivity analyses, was accomplished. These studies indicated that substantial gains were possible in reducing operating costs by incorporating both the low risk technology and innovative designs available in 1985, and advanced technology such as composite structures available at a later time. Additional effort is required to identify this increased cost of higher risk advanced technology to determine its cost effectiveness. In Phase II, a baseline mission requiring 3600 nm radius and 400,000 lb. payload was selected., Original contains color plates: All DDC reproductions will be in black and white. See also Volume 2, AD-A044 319.