A Brief Summary of Some of the Laboratory Astrophysics Workshop

Our present knowledge of the molecular universe has come primarily from radio observations [ I include here millimeter and submillimeter in this rubric]. There are a number of reasons for this but the primary one is the extremely high spectral resolution. The ease of observing emission from the volume of dense molecular clouds without significant attenuation by scattering from dust has shown this to be the powerful observational tool for molecular astronomy. Finally the relative simplicity of rotational compared to vibrational or electronic spectroscopy allows carrier identification as well as facile evaluation of cloud conditions such as density and temperature. These virtues become tenuous as the astronomical observations are pushed to higher frequencies for enhanced observational sensitivity. Thus precision rest frequencies are mandatory for the search for new species. We may inquire about which new species require particular attention, and which species may be relatively safely predicted on the basis of lower frequency laboratory measurements. For a rigid rotor the three rotational constants are sufficient to completely specify the transition frequencies. The intensities require the three components of the electric dipole moment. For semirigid species, where the centrifugal distortion, may be treated at the quartic level of angular momentum (Bunker et al. 1998), up to five additional constants are required (Watson 1967). There are a number of such species of considerable interest, where laboratory measurements are adequate for astronomical searches

Decision guides for forest practice laws in Oregon

Spawned by the current interest in revising Oregon's Forest Conservation Act, this study defines the forestry regulation problem and outlines theoretical approaches to its solution. Unregulated private forestry is found to present opportunities for government intervention, the gains from which could exceed the losses. Proposed is a public goal of maximizing net satisfactions from Oregon's private forest lands, subject to specified constraints and assumptions This goal is derived in a chapter on welfare economics. Following an evaluation of past regulation goals and approaches, the study discusses guidelines for regeneration and logging regulations consistent with the assumed regulatory objective In a full employment economy it appears that public regulation of private forestry is which the unregulated market would attain (ignoring non-wood benefits). However, government leasing of private land for wood production does provide a possibility of increased satisfactions from wood output. Upon considering non-market forest benefits and undesirable side-effects of logging, welfare-increases from intervention are shown to be possible. After reviewing the concept of optimal levels of spill-over effects, the study points out the possibility that optimal levels of nonmarket damages could depend on whether the liability for damage reduction is placed on the victims or the damager. Considering both liability viewpoints, a scheme for determining optimal regeneration regulations is outlined for cases where non-market values are at stake. Approaches to optimizing levels of external non-market damages from logging are then examined under each liability scheme, considering actions causing changes in single or joint benefits. The importance of distinguishing between mutually exclusive and additive management practices is illustrated. Forestry-caused environmental changes discussed under nonmarket benefits include variations in water siltation and temperature, fish and big game populations, and scenic beauty. The study aims to assist economists advising planners of forest practices legislation and administrative regulations. Much of the information presented would be useful in designing such intervention today to approach the study's assumed regulatory goal. Other more detailed decision guides are proposed for research to determine optimal regulations on study areas. Broad application of such research results could increase welfare by a greater amount than could preliminary regulations designed immediately. Throughout the study, emphasis is placed upon the need for, and possibility of, making incremental analyses comparing marginal benefits and costs even when these marginal quantities are in different units. Evaluation of regulatory alternatives is left to decision makers, the study simply illustrates ways of arraying and comparing alternatives and points out implications of various approaches to forest practices regulation

Hydrated sulphuric acid in dense molecular clouds

We consider sulphur depletion in dense molecular clouds, and suggest hydrated sulphuric acid, H2SO4 · nH2O, as a component of interstellar dust in icy mantles. We discuss the formation of hydrated sulphuric acid in collapsing clouds and its instability in heated regions in terms of the existing hot core models and observations. We also show that some features of the infrared spectrum of hydrated sulphuric acid have correspondence in the observed spectra of young stellar objects.Physic

The Structure, Anharmonic Vibrational Frequencies, and Intensities of NNHNN+

A semi-global potential energy surface (PES) and quartic force field (QFF) based on fitting high-level electronic structure energies are presented to describe the structures and spectroscopic properties of NNHNN+. The equilibrium structure of NNHNN+ is linear with the proton equidistant between the two nitrogen groups and thus of D(sub h) symmetry. Vibrational second-order perturbation theory (VPT2) calculations based on the QFF fails to describe the proton rattle motion, i.e., the antisymmetric proton stretch, due to the very flat nature of PES around the global minimum, but performs properly for other modes with sharper potential wells. Vibrational self-consistent field/virtual state configuration interaction (VSCF/VCI) calculations using a version of MULTIMODE without angular momentum terms successfully describe this motion and predict the fundamental to be at 759 cm(exp -1). This is in good agreement with the value of 746 cm(exp -1) from a fixed-node diffusion Monte Carlo calculation and the experimental Ar-tagged result of 743 cm(exp -1). Other VSCF/VCI energies are in good agreement with other experimentally reported ones. Both double-harmonic intensity and rigorous MULTIMODE intensity calculations show the proton transfer fundamental has a very strong intensity