Circular 45

This circular provides guidance on fertilizing native hay meadows of bluejoint reedgrass (Calamagrostis canadensis) on the lower Kenai Peninsula. It is based on a num ber o f experim ental trials conducted by the authors on Kachemak silt loam soil at various sites near Homer

An orbital window into the ancient Sun's mass

Models of the Sun's long-term evolution suggest that its luminosity was substantially reduced 2-4 billion years ago, which is inconsistent with substantial evidence for warm and wet conditions in the geological records of both ancient Earth and Mars. Typical solutions to this so-called "faint young Sun paradox" consider changes in the atmospheric composition of Earth and Mars, and while attractive, geological verification of these ideas is generally lacking-particularly for Mars. One possible underexplored solution to the faint young Sun paradox is that the Sun has simply lost a few percent of its mass during its lifetime. If correct, this would slow, or potentially even offset the increase in luminosity expected from a constant-mass model. However, this hypothesis is challenging to test. Here, we propose a novel observational proxy of the Sun's ancient mass that may be readily measured from accumulation patterns in sedimentary rocks on Earth and Mars. We show that the orbital parameters of the Solar system planets undergo quasi-cyclic oscillations at a frequency, given by secular mode g_2-g_5, that scales approximately linearly with the Sun's mass. Thus by examining the cadence of sediment accumulation in ancient basins, it is possible distinguish between the cases of a constant mass Sun and a more massive ancient Sun to a precision of greater than about 1 per cent. This approach provides an avenue toward verification, or of falsification, of the massive early Sun hypothesis.Comment: 7 pages, 4 Figures. Accepted to The Astrophysical Journal Letter

Traffic control system and method

Frequency of carrier received by aircraft is measured and compared with reference to indicate magnitude of Doppler shift. One Doppler frequency range is selected and indicated by digital signal. Difference between frequency is offset of apparent carrier frequency transmitted by aircraft

Traffic control system and method Patent

Traffic control system for supersonic transports using synchronous satellite for data relay between vehicles and ground statio

Remote sensing of the atmosphere from environmental satellites

Various applications of satellite remote sensing of the earth are reviewed, including (1) the use of meteorological satellites to obtain photographic and radiometric data for determining weather conditions; (2) determination of the earth radiation budget from measurements of reflected solar radiation and emitted long wave terrestrial radiation; (3) the use of microwave imagery for measuring ice and snow cover; (4) LANDSAT visual and near infrared observation of floods and crop growth; and (5) the use of the Nimbus 4 backscatter ultraviolet instrument to measure total ozone and vertical ozone distribution. Plans for future activities are also discussed

Laughlin type wave function for two-dimensional anyon fields in a KMS-state

The correlation functions of two-dimensional anyon fields in a KMS-state are studied. For T=0 the $n$-particle wave functions of noncanonical fermions of level $\alpha$, $\alpha$ odd, are shown to be of Laughlin type of order $\alpha$. For $T>0$ they are given by a simple finite-temperature generalization of Laughlin's wave function. This relates the first and second quantized pictures of the fractional quantum Hall effect.Comment: 9 pages, LaTeX, comments and references added (version to appear in Physics Letters B

A determination of the spin-orbit alignment of the anomalously dense planet orbiting HD 149026

We report 35 radial velocity measurements of HD 149026 taken with the Keck Telescope. Of these measurements, 15 were made during the transit of the companion planet HD 149026b, which occurred on 2005 June 25. These velocities provide a high-cadence observation of the Rossiter-McLaughlin effect, the shifting of photospheric line profiles that occurs when a planet occults a portion of the rotating stellar surface. We combine these radial velocities with previously published radial velocity and photometric data sets and derive a composite best-fit model for the star-planet system. This model confirms and improves previously published orbital parameters, including the remarkably small planetary radius, the planetary mass, and the orbital inclination, found to be Rp/RJup = 0.718 ± 0.065, Mp/MJup = 0.352 ± 0.025, and I = 86.1° ± 1.4°, respectively. Together the planetary mass and radius determinations imply a mean planetary density of 1.18(-0.30)(+0.38)g cm(-3). The new data also allow for the determination of the angle between the apparent stellar equator and the orbital plane, which we constrain to be λ = -12° ± 15°

Magnetic Instability in Strongly Correlated Superconductors

Recently a new phenomenological Hamiltonian has been proposed to describe the superconducting cuprates. This so-called Gossamer Hamiltonian is an apt model for a superconductor with strong on-site Coulomb repulsion betweenthe electrons. It is shown that as one approaches half-filling the Gossamer superconductor, and hence the superconducting state, with strong repulsion is unstable toward an antiferromagnetic insulator an can undergo a quantum phase transition to such an insulator if one increases the on-site Coulomb repulsion

Testing the locality of transport in self-gravitating accretion discs - II. The massive disc case

In this paper, we extend our previous analysis (Lodato & Rice 2004) of the transport properties induced by gravitational instabilities in cooling, gaseous accretion discs to the case where the disc mass is comparable to the central object. In order to do so, we have performed global, three-dimensional smoothed particle hydrodynamics simulations of massive discs. These new simulations show a much more complex temporal evolution with respect to the less massive case. Whereas in the low disc mass case a self-regulated, marginally stable state (characterized by an approximately constant radial profile of the stability parameter $Q$) is easily established, in the high disc mass case we observe the development of an initial transient and subsequent settling down in a self-regulated state in some simulations, or a series or recurrent spiral episodes, with low azimuthal wave number $m$, in others. Accretion in this last case can therefore be a highly variable process. On the other hand, we find that the secular evolution of the disc is relatively slow. In fact, the time-average of the stress induced by self-gravity results in accretion time-scales much longer than the dynamical timescale, in contrast with previous isothermal simulations of massive accretion discs. We have also compared the resulting stress tensor with the expectations based on a local theory of transport, finding no significant evidence for global wave energy transport.Comment: MNRAS, accepted (higher quality, colour figures can be found at http://www.ast.cam.ac.uk/~giuseppe/Publications/Locality_II/

A Study of the Effects of Quick Freezing on Saturated Fragments of Rocks

Quick freezing of a fragment of rock which is fully saturated with water is, perhaps, the most rigorous of all tests for soundness, durability, or resistance to weathering. So-called soundness or quality tests employed currently, or heretofore, for evaluating concrete aggregates are usually less rigorous inasmuch as the state of saturation at the outset of freezing is not at a critical level. Hence, the number of freeze-thaw cycles endured by a rock specimen undergoing freezing and thawing in the presence of available water may merely reflect the duration of the exposure before the rock becomes vulnerable to damage -- i.e., time required for critical saturation. Damage arises wholly from the combined effects of the volume dilation accompanying the freezing of absorbed water, the dilation pressure induced, and the inherent restraining strength of the aggregate particle. Thus, the severest freezing condition, to which rock or concrete may be exposed, occurs after long periods of sustained wetting -- when the degree of saturation is the highest