Experimenter's data package for the descending layers rocket

In response to a proposal from Science Applications International Corporation (SAIC), NASA Headquarters has approved a sounding rocket mission designed to study the physics of intermediate layers in the Earth's ionosphere at middle latitudes. The experiment will be carried out by a team of scientists and engineers from the NASA Wallops Flight Facility, SAIC, the NASA Goddard Space Flight Center, and the Millstone Hill radar observatory. The mission will involve the launch of an instrumented sounding rocket from the Wallops Island rocket range in the summer of 1994, with the objective of penetrating a descending ionized layer in the E-region between altitudes of 115 and 140 km. Instrumentation aboard the rocket will measure the ion and neutral composition of the layer, its plasma density, driving wind and electric field forces, the thermal ion distribution function, and electron temperature. Depending on payload weight constraints and subject to availability, a particle detector to measure energetic ion and/or electron fluxes near the layer may also be included. This document was prepared as a reference for the NASA payload development and experiment teams, for distribution at the Project Initiation Conference (PIC). The design specifications discussed herein are therefore of a preliminary nature; the intent is to promote open discussions between experimenters and NASA engineers that will lead to a final design capable of achieving the experiment objectives

The behavior of the electron density and temperatue at Millstone Hill during the equinox transition study September 1984

The ionospheric electron density and temperature variations is simulated during the equinox transition study in September 1984 and the results are compared with measurements made at Millstone Hill. The agreement between the modeled and measured electron density and temperature for the quiet day (18 September) is very good but there are large differences on the day of the storm (19 September). On the storm day, the measured electron density decreases by a factor of 1.7 over the previous day, while the model density actually increases slightly. The model failure is attributed to an inadequate increase in the ratio of atomic oxygen to molecular neutral densities in the MSIS neutral atmosphere model, for this particular storm. A factor of 3 to 5 increase in the molecular to atomic oxygen density ratio at 300 km is needed to explain the observed decrease in electron density. The effect of vibrationally excited N sub 2 on the electron density were studied and found to be small

Individuazione degli errori di scheggiatura nei diversi metodi di débitage del Paleolitico inferiore e medio. Gli esempi di Cà Belvedere di Monte Poggiolo (FC), Guado San Nicola 1 (IS), Riparo Tagliente (VR), Payre e Abri du Maras (Ardéche, Francia).

The understanding of the management of natural resources by prehistoric man through an analysis of stone tools is useful to create parameters for the study of the level of manual dexterity and subsistence strategies in the Paleolithic. The study of knapping errors in experimental and archaeological lithic collections can reveal the presence of beginners or of experienced knappers and offers a comprehensive overview on the various errors associated with different methods of knapping débitage. This is because each lithic collection presents its own techno-typological peculiarities, resulting from various factors, which involve a subdivision of the observable and recognizable characteristics for each technique and method of débitage that was involved. Contextualizing knapping-errors within the reduction sequence is also useful to understand whether the identified errors can or cannot be placed in the variability in which an expert knapper may also incur or whether they are due solely to lack of experience. The analysis of the experimental material also allows classification of errors in relation to their causes and their effects on the manufact. Through a comparison with lithic archaeological collections it is possible to observe the livelihood strategies and the way of explanation of the learning process within human groups. In a broader context, it is possible to understand the internal structure of the paleolithic communities, the division of labor within them and the different spatial localization of the daily activities performed. For a correct analysis focused on the study of knapping errors, a comparison between the archaeological material and experimental material is absolutely necessary. The experimental lithic assemblages are composed by two collections, the first from the Intensive Programme (IP Socrates-Erasmus) held at the CERP (European Centre for Prehistoric Research) of Isernia, the second constituted by lithic artifacts from experimental operations carried out by students of Lithic Technology class which took place at the University of Ferrara. The first step was a classification of knapping errors and the identification of causes and effects of a particular dexterity. Successively, the research focused on the study of records from five archaeological sites, aimed at finding the categories of errors previously recognized by experimentation. The case studies relate to two different contexts of Italian Lower Paleolithic, Ca Belvedere di Monte Poggiolo (FC) (Peretto et al., 1998) and Guado San Nicola 1 (IS) (Arzarello et al., 2009), and three sites of the Middle Paleolithic: Riparo Tagliente (VR) (Bartolomei et al., 1982), Payré (Moncel et al. 2002) and Abri du Maras (Moncel, 1996), the latter two being located in Ardéche, France. By comparison of lithic archaeological sites with experimental collections, it was observed that it is possible to find the same errors on experimentally reproduced artifacts and archaeological products. This lead us to understand not only that the raw material responds always in the same way to a certain gesture, but also that a particular gesture is an obligatory step in the learning process. This aspect has been proven true also in diachronic contexts, because there is no difference between the type of error identified, and the age of lithic assemblages. Indeed, the examined sites cover a range of 900 thousand years, but errors due to a particular gesture affect in the same way a product of the Lower Paleolithic of Ca’ Belvedere di Monte Poggiolo and an artifact of the Middle Paleolithic of Riparo Tagliente. It has proved difficult but not impossible, to make a clear distinction between a possible group of beginners from expert flint-knappers in the archaeological records, especially for the older sites like Monte Poggiolo and Guado San Nicola. On the other hand, It has been possible to identify the type of dexterity we were dealing with. The important result of this work is the interpretation of errors in the knapping, not only to classify the causes and effects, but especially to relate to a specific dexterity, whether it identifies a beginner or not. In conclusion, the identification of errors in knapping in archaeological contexts, allows to define not only the presence of beginning knappers in a site, but also to set the level of learning and the skill of a prehistoric group

Observations of neutral circulation at mid-latitudes during the Equinox Transition Study

Measurements of ion drift velocity made by the Millstone Hill incoherent scatter radar have been used to calculate the meridional neutral wind velocity during the Sept. 17 to 24, 1984 period. Strong daytime southward neutral surges were observed during the magnetically disturbed days of September 19 and 23, in contrast to the small daytime winds obtained as expected during the magnetically quiet days. The surge on September 19 was also seen at Arecibo. In addition, two approaches have been used to calculate the meridional wind component from the radar-derived height of the F-layer electron density peak. Results confirm the wind surge, particularly when the strong electric fields measured during the disturbed days are included in the calculations. The two approaches for the F-layer peak wind calculations are applied to the radar-derived electron density peak height as a function of latitude to study the variation of the southward daytime surges with latitude

On the possibility of radar echo detection of ultra-high energy cosmic ray- and neutrino-induced extensive air showers

We revisit and extend the analysis supporting a 60 year-old suggestion that cosmic rays air showers resulting from primary particles with energies above 10^{18} eV should be straightforward to detect with radar ranging techniques, where the radar echoes are produced by scattering from the column of ionized air produced by the shower. The idea has remained curiously untested since it was proposed, but if our analysis is correct, such techniques could provide a significant alternative approach to air shower detection in a standalone array with high duty cycle, and might provide highly complementary measurements of air showers detected in existing and planned ground arrays such as the Fly's Eye or the Auger Project. The method should be particularly sensitive to showers that are transverse to and relatively distant from the detector, and is thus effective in characterizing penetrating horizontal showers such as those that might be induced by ultra-high energy neutrino primaries.Comment: 29 pages, 16 figures, uses aas2pp4.sty. Final version, to appear in Astroparticle Physics. Contains new figs, better estimate of angular precision possibl

Superthermal electron energy interchange in the ionosphere‐plasmasphere system

A self‐consistent approach to superthermal electron (SE) transport along closed field lines in the inner magnetosphere is used to examine the concept of plasmaspheric transparency, magnetospheric trapping, and SE energy deposition to the thermal electrons. The dayside SE population is generated both by photoionization of the thermosphere and by secondary electron production from impact ionization when the photoelectrons collide with upper atmospheric neutral particles. It is shown that a self‐consistent approach to this problem produces significant changes, in comparison with other approaches, in the SE energy exchange between the plasmasphere and the two magnetically conjugate ionospheres. In particular, plasmaspheric transparency can vary by a factor of two depending on the thermal plasma content along the field line and the illumination conditions of the two conjugate ionospheres. This variation in plasmaspheric transparency as a function of thermal plasma and ionospheric conditions increases with L ‐shell, as the field line gets longer and the equatorial pitch angle extent of the fly‐through zone gets smaller. The inference drawn from these results is that such a self‐consistent approach to SE transport and energy deposition should be included to ensure robustness in ionosphere‐magnetosphere modeling networks. Key Points A self‐consistent approach alters the SE energy exchange in the I‐P system Plasmaspheric transparency varies with the thermal plasma and illumination SE transport and energy dep should be included in M‐I modeling networksPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97456/1/jgra50127.pd

Global model comparison with Millstone Hill during September 2005

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95551/1/jgra18878.pd