Lyman Alpha and MgII as Probes of Galaxies and their Environments

Ly{\alpha} emission, Ly{\alpha} absorption and MgII absorption are powerful tracers of neutral hydrogen. Hydrogen is the most abundant element in the universe and plays a central role in galaxy formation via gas accretion and outflows, as well as being the precursor to molecular clouds, the sites of star formation. Since 21cm emission from neutral hydrogen can only be directly observed in the local universe, we rely on Ly{\alpha} emission, and Ly{\alpha} and MgII absorption to probe the physics that drives galaxy evolution at higher redshifts. Furthermore, these tracers are sensitive to a range of hydrogen densities that cover the interstellar medium, the circumgalactic medium and the intergalactic medium, providing an invaluable means of studying gas physics in regimes where it is poorly understood. At high redshift, Ly{\alpha} emission line searches have discovered thousands of star-forming galaxies out to z = 7. The large Ly{\alpha} scattering cross-section makes observations of this line sensitive to even very diffuse gas outside of galaxies. Several thousand more high-redshift galaxies are known from damped Ly{\alpha} absorption lines and absorption by the MgII doublet in quasar and GRB spectra. MgII, in particular, probes metal-enriched neutral gas inside galaxy haloes in a wide range of environments and redshifts (0.1 < z < 6.3), including the so-called redshift desert. Here we review what observations and theoretical models of Ly{\alpha} emission, Ly{\alpha} and MgII absorption have told us about the interstellar, circumgalactic and intergalactic medium in the context of galaxy formation and evolution.Comment: 59 Pages, 19 Figures, 1 Table. Accepted for publication in Publications of the Astronomical Society of the Pacifi

Evaluating Board Leaders

Evaluating the performance of leaders is critical to the development of organizations and communities. Evaluation means measuring performance by defining a set of metrics. But which performance metrics should be used? From a review of the work by Collins (2001), we developed a tool that provides one way to measure the performance of leaders. We apply this to the case of leaders of boards. Clearly defining leader performance expectations is one of the most critical steps a board can take to prevent misunderstandings and therefore hedge against the emergence of unresolved conflict among board members and their respective leader

Apollo lunar surface experiments operational requirements

The Apollo Lunar Surface Operational Requirements document delineates the operating concepts and the real-time support requirements for the Apollo Lunar Surface Experiments Package (ALSEP) program and the Early Apollo Scientific Experiments Package (EASEP) program.Contract NASw-410. Task Order MSC No. 38prepared by General Electric Company for Lunar Surface Project Office, Manned Spacecraft Center ; prepared by Glenn P. Barnes.Introduction -- ALSEP/ EASEP telemetry -- Real -time support -- Specific experiment requirement

Apollo lunar surface experiments mission requirements plan : EASEP/LGE mission

This document is a compilation of pertinent data and information extracted from the documentation generated for the design, test, checkout, and operation of the Early Apollo Scientific Experiments Package (EASEP) and the Lunar Geology Experiment (LGE)."--Prepared by General Electric Company for Lunar Surface Project Office ... under contract NASw-410prepared by Glenn P. BarnesIntroduction -- Mission objectives -- Mission description -- Phase I (lunar surface EVA phase) -- Phase II (lunar surface operation checkout phase) -- Phase III (forty-five day phase) -- Phase IV (one year phase

Science operations support plan mission J-1/Apollo 15 final

Included in this document are pertinent data resulting from the Principal Investigator's Operational Interface Meetings and are intended for use by the Principal Investigators, members of the scientific community, and personnel responsible for planning and supporting mission science requirements. These data define the scientific experiments operations, the lunar geology investigation, and the crew activities during the lunar surface operation phases.prepared by Glenn P. Barnes

Navigation Doppler Lidar for Autonomous Ground, Aerial, and Space Vehicles

A Doppler lidar instrument has been developed and demonstrated for providing critical vector velocity and altitude/range data for autonomous precision navigation. Utilizing advanced component technologies, this lidar can be adapted to different types of vehicles

Differences in Academic Performance by School District Size for Students in Special Education: A Multiyear, Statewide Investigation

In this empirical statewide multiyear analysis the extent to which the academic performance of students enrolled in special education was influenced by school district student enrollment was determined Five years of Texas statewide data on the Texas Assessment Knowledge Skills Reading Mathematics Science Social Studies and Writing exams were analyzed as a function of three school district sizes a small-size up to 1 599 students b moderate-size 1 600 to 9 999 students and c large-size 10 000 or more students Inferential statistical procedures revealed that students in special education who were enrolled in large-size school districts had statistically significantly higher passing rates on all five exams than did students in special education who were enrolled in either moderate-size or small-size school districts for all 5 years Effect sizes were smal

Coherent Doppler Lidar for Precision Navigation of Spacecrafts

A fiber-based coherent Doppler lidar, utilizing an FMCW technique, has been developed and its capabilities demonstrated through two successful helicopter flight test campaigns. This Doppler lidar is expected to play a critical role in future planetary exploration missions because of its ability in providing the necessary data for soft landing on the planetary bodies and for landing missions requiring precision navigation to the designated location on the ground. Compared with radars, the Doppler lidar can provide significantly higher precision velocity and altitude data at a much higher rate without concerns for measurement ambiguity or target clutter. Future work calls for testing the Doppler lidar onboard a rocket-powered free-flyer platform operating in a closed-loop with the vehicle s guidance, navigation, and control (GN&C) unit

Doppler Lidar Sensor for Precision Landing on the Moon and Mars

Landing mission concepts that are being developed for exploration of planetary bodies are increasingly ambitious in their implementations and objectives. Most of these missions require accurate position and velocity data during their descent phase in order to ensure safe soft landing at the pre-designated sites. To address this need, a Doppler lidar is being developed by NASA under the Autonomous Landing and Hazard Avoidance (ALHAT) project. This lidar sensor is a versatile instrument capable of providing precision velocity vectors, vehicle ground relative altitude, and attitude. The capabilities of this advanced technology have been demonstrated through two helicopter flight test campaigns conducted over a vegetation-free terrain in 2008 and 2010. Presently, a prototype version of this sensor is being assembled for integration into a rocket-powered terrestrial free-flyer vehicle. Operating in a closed loop with vehicle's guidance and navigation system, the viability of this advanced sensor for future landing missions will be demonstrated through a series of flight tests in 2012

Charmonium Decay Physics

Recent experimental results on the decays of charmonium, together with related physics issues, are reviewed. Some future prospects are described.Comment: 8 pages, latex, no figures. Invited talk at the 8th International Conference on Hadron Spectroscopy (Hadron99), Beijing, 24-28 august, 1999; to appear in Proceeding