Risk Assessments for Chemical Stockpile Incinerators: Is the Supporting Guidance Adequate

The author identifies potential deficiencies in guidance used in the United States for risk assessments of chemical weapons incinerators

Identifying Dark Matter Burners in the Galactic center

If the supermassive black hole (SMBH) at the center of our Galaxy grew adiabatically, then a dense "spike" of dark matter is expected to have formed around it. Assuming that dark matter is composed primarily of weakly interacting massive particles (WIMPs), a star orbiting close enough to the SMBH can capture WIMPs at an extremely high rate. The stellar luminosity due to annihilation of captured WIMPs in the stellar core may be comparable to or even exceed the luminosity of the star due to thermonuclear burning. The model thus predicts the existence of unusual stars, i.e. "WIMP burners", in the vicinity of an adiabatically grown SMBH. We find that the most efficient WIMP burners are stars with degenerate electron cores, e.g. white dwarfs (WD) or degenerate cores with envelopes. If found, such stars would provide evidence for the existence of particle dark matter and could possibly be used to establish its density profile. In our previous paper we computed the luminosity from WIMP burning for a range of dark matter spike density profiles, degenerate core masses, and distances from the SMBH. Here we compare our results with the observed stars closest to the Galactic center and find that they could be consistent with WIMP burners in the form of degenerate cores with envelopes. We also cross-check the WIMP burner hypothesis with the EGRET observed flux of gamma-rays from the Galactic center, which imposes a constraint on the dark matter spike density profile and annihilation cross-section. We find that the EGRET data is consistent with the WIMP burner hypothesis. New high precision measurements by GLAST will confirm or set stringent limits on a dark matter spike at the Galactic center, which will in turn support or set stringent limits on the existence of WIMP burners at the Galactic center.Comment: 2 pages, 2 figures; to appear in the Proc. of the First Int. GLAST Symp. (Stanford, Feb. 5-8, 2007), eds. S.Ritz, P.F.Michelson, and C.Meegan, AIP Conf. Pro

Characteristics of a variable spaced planar thermionic converter with a tungsten emitter and a niobium collector

Current-voltage characteristics of variable spaced thermionic converter with tungsten emitter and niobium collecto

How severe is the time-inconsistency problem in monetary policy?

This study analyzes two monetary economies, a cash-credit good model and a limited-participation model. In these models, monetary policy is made by a benevolent policymaker who cannot commit to future policies. The study defines and analyzes Markov equilibrium in these economies and shows that there is no time-inconsistency problem for a wide range of parameter values.Monetary policy ; Inflation (Finance) ; Money supply

Expectation Traps and Monetary Policy

We describe a class of monetary economies that generate persistent episodes of high and low inflation. In this class of economies, variations in expectations can lead private agents to take actions which then make it optimal for the monetary authority to validate those expectations. We think these models deserve attention because they display several good empirical properties.Inflation Time-Consistency

Expectation traps and monetary policy

Why is inflation persistently high in some periods and low in others? The reason may be absence of commitment in monetary policy. In a standard model, absence of commitment leads to multiple equilibria, or expectation traps, even without trigger strategies. In these traps, expectations of high or low inflation lead the public to take defensive actions, which then make accommodating those expectations the optimal monetary policy. Under commitment, the equilibrium is unique and the inflation rate is low on average. This analysis suggests that institutions which promote commitment can prevent high inflation episodes from recurring.Monetary policy ; Inflation (Finance) ; Consumer behavior

The use of an airborne lidar for mapping cirrus clouds in FIRE, phase 2

The Univ. of Washington (UW) and Georgia Tech have recently built a dual wavelength airborne lidar for operation on the UW's Convair C-131A research aircraft. This lidar was used in studying aerosols and clouds. These studies demonstrated the utility of airborne lidar in a variety of atmospheric research and prompt the suggestion that this facility be included in the next FIRE cirrus experiment. The vertically pointing airborne lidar would be used as a complement to ground based lidars. The airborne lidar would ensure extended coverage of IFO cases that develop upwind of the surface lidars or which miss the ground based lidars while still being the focus of satellite and aircraft in situ studies. The airborne lidar would help assure that cirrus clouds were simultaneously viewed by satellite, sampled by aircraft, and structurally characterized by lidar. System specifications are listed and a schematic is shown of the lidar system aboard the C-131A

Contradictory uncertainty relations

We show within a very simple framework that different measures of fluctuations lead to uncertainty relations resulting in contradictory conclusions. More specifically we focus on Tsallis and Renyi entropic uncertainty relations and we get that the minimum uncertainty states of some uncertainty relations are the maximum uncertainty states of closely related uncertainty relations, and vice versa.Comment: 4 pages, 10 figure

Looking Beyond AFTA: Prospects and Challenges for Inter-regional Trade

The world-trading environment has witnessed the proliferation of regional trading arrangements during the last decade. This development has been accompanied by the perceived threat this may bring to the rules-based multilateral trading system. The Association of Southeast Nations (ASEAN), for its part, has not only reaffirmed its commitment to move forward beyond the ASEAN Free Trade Area (AFTA) and toward a higher level of economic integration, but is also looking at enhanced interaction and closer linkages with other regional groupings. This paper examines the prospects and challenges for expanding AFTA for inter-regional trade by first identifying the elements and principles that should govern such an expansion for it to contribute toward global liberalization. Areas for inter-regional linkages are also identified, highlighting the issues and conflicts that may arise considering the differing objectives and scope that AFTA has with the other trade blocs with which it may want to develop an inter-regional linkage. Some probable arrangements for linking/expanding AFTA with other groupings or non-ASEAN countries are then explored, particularly those involving the Australia-New Zealand Closer Economic Relation (CER), the East Asian Countries and the Andean Community.trade liberalization, trade reforms, trade sector, liberalization, ASEAN, trade policies, Andean Community