The SOFIA Telescope

The SOFIA telescope as the heart of the observatory is a major technological challenge. I present an overview on the astro-nomical and scientific requirements for such a big airborne observatory and demonstrate the impact of these requirements on the layout of SOFIA, in particular on the telescope design as it is now. Selected components of the telescope will be de-scribed in their context and functionality. The current status of the telescope is presented.Comment: 6 pages, 7 figures, to appear in: Proceedings of SPIE: Airborne Telescope Systems, Munich, March 2000, Vol. 4014, paper with high resolution figures available at http://astro1.ws.ba.dlr.de/WEBPAGES/paper.ht

The Role of Consultants for Danish Farmers Coping with the Change in Farming Conditions

An overview of a modern consultancy service to Danish farmers is given. The Danish model includes technical advice, farm management and accounting. Good consultants, new products, goal settings and campaigns are described.Consulting, key account consultants, accounting, goal setting, farming, LandboNord, Denmark, Farm Management, Teaching/Communication/Extension/Profession,

Stabilizing, Pareto Improving Policies in an OLG model with Incomplete Markets: The Rational Expectations and Rational Beliefs Case.

One way to interpret the current policies of many central banks is that they seek to stabilize economic activity. One possible justification for such a policy is that there is volatility in macro variables that individual agents cannot insure against. We study the simplest possible extension of the stochastic 2-period, one agent and one commodity OLG model, where we have added 1 more period, with only one potential activity, namely trading of contingent commodities. We assume, however, that markets are incomplete. In this case the monetary equilibrium is not Pareto Optimal and for an open set of economies an equilibrium where fluctuations in realized savings are removed Pareto dominates the monetary equilibrium. A combination of fiscal and monetary policy may achieve this equilibrium . The policy considered has a simple rationale, namely that it removes some of the uncertainty that agents face by reducing price or interest rate volatility. We consider two fundamental sources of such volatility, namely respectively an objective and a subjective signal about the distribution of future endowments. The first case is when agents have Rational Expectations while the second case is studied in the context of agents having Rational Beliefs, beliefs which are consistent with empirical observations but not (necessarily) correct.}Stabilization, Rational Beliefs, Rational Expectations, Incomplete markets

Rational overconfidence and excess volatility in general equilibrium

Rational beliefs (in the form of WAMS measures) are expectations which though consistent with empirical observations, may deviate from the true underlying probability measure under which data is generated.We provide results on, as well as a decomposition of, WAMS measures and use this to demonstrate that an agent that adopts a non-stationary rational belief is rationally overconfident.To apply the theory to models of general equilibrium, we introduce the concept of a sunspot rational beliefs structure which can be considered as the exogenously specified part of a state process with rational beliefs. As an application, we consider an continuous state space model where agents make production decision before knowing prices. Under rational beliefs, unlike under rational expectations, mistakes persist even though all agents make forecasts that are statistically consistent with the equilibrium process. Due to the correlation of subjective beliefs brought about by the sunspots, the equilibrium exhibits excess price volatility.Rational Beliefs, Rational Overconfidence, Excess Volatility

Near-infrared integral-field spectroscopy of HD209458b

We present first results of an exploratory study to use integral field spectroscopy to observe extrasolar planets. We focus on transiting "Hot Jupiters" and emphasize the importance of observing strategy and exact timing. We demonstrate how integral field spectroscopy compares with other spectroscopic techniques currently applied. We have tested our concept with a time series observation of HD209458b obtained with SINFONI at the VLT during a superior conjunction.Comment: SPIE conference proceeding, Astronomical telescopes and instrumentation, Orlando, 200

Contracting with Risk Aversion and Subjective Beliefs Under Costly State Verification

We study the loan contracing problem of Gale and Hellwig (1985) under general assumptions of risk aversion and possibly diverse subjective beliefs of the borrower and lender about the income of the investment. We characterize the optimal contract and show that (i) the contractual payoff in verification states varies by states in accord with risk aversion and probability belief of the borrower and lender, and (ii) teh verification region may consist of many intervals. Under these general assumptions, verification states are not necessarily interpreted as "default" states. Rather, they also reflect the need of the parties to trade on their differences in probability in the absence of markets for contingent claimsFinancial contract, costly state verification, risk aversion, subjective expectations

Seyfert Activity and Nuclear Star Formation in the Circinus Galaxy

We present high angular resolution (0".15-0".5) near infrared images and spectroscopy of the Circinus galaxy, the closest Seyfert 2 galaxy known. The data reveal a non-stellar nuclear source at 2.2 microns. The coronal line region and the hot molecular gas emission extend for 20-50 pc in the ionization cone. The data do not show evidence for a point-like concentration of dark mass; we set an upper limit of 4*10^6 Mo to the mass of a putative black hole. We find evidence for a young nuclear stellar population, with typical ages between 4*10^7 and 1.5*10^8 yrs. The luminosity of the starburst inside a few hundred pc is comparable to the intrinsic luminosity of the Seyfert nucleus, and the two of them together account for most of the observed bolometric luminosity of the galaxy. Within the central 12 pc the starburst has an age of about 7*10^7 yrs and radiates about 2% of the luminosity of the active nucleus. We discuss the implications of these results for models that have been proposed for the starburst-AGN connection.Comment: 44 pages, Latex (including 11 Figures), Color Figures 1, 2 and 4 are available at http://www.arcetri.astro.it/~maiolino/ , ApJ in pres