Polarization Maintaining, Very-Large-Mode Area, Er Fiber Amplifier for High Energy Pulses at 1572.3 nm

We demonstrate the first polarization maintaining, very-large-mode-area Er-doped fiber amplifier with ~1000 square micron effective area. The amplifier is core pumped by a Raman fiber laser and is used to generate single frequency one microsecond pulses with pulse energy of 368 microJoules, M2 of 1.1, and polarization extinction greater than 20 dB. The amplifier operates at 1572.3 nm, a wavelength useful for trace atmospheric CO2 detection

Fiber-Based Laser Transmitter at 1.57 Micrometers for Remote Sensing of Atmospheric Carbon Dioxide from Satellites

Over the past 20 years, NASA Goddard has successfully developed space-based lidar for remote sensing studies of the Earth and planets. The lidar in all missions to date have used diode pumped Nd:YAG laser transmitters. Recently we have been concentrating work on developing integrated path differential absorption (IPDA) lidar to measure greenhouse gases, with the goal of measurements from space. Due to the absorption spectrum of CO2 a fiber-based master oscillator power amplifier (MOPA) laser with a tunable seed source is an attractive laser choice. Fiber-based lasers offer a number of potential advantages for space, but since they are relatively new, challenges exist in developing them. In order to reduce risks for new missions using fiber-based lasers, we developed a 30- month plan to mature the technology of a candidate laser transmitter for space-based CO2 measurements to TRL-6. This work is also intended to reduce development time and costs and increase confidence in future mission success

The meaning of anger for Australian indigenous offenders - The significance of context

The problem of overrepresentation of Indigenous offenders in Australian prisons highlights the need for effective tertiary intervention programs within correctional settings as a way of reducing Indigenous reincarceration. This study seeks to explore meanings of anger within an Indigenous context that might inform the development of more acceptable and potentially more effective rehabilitation programs. A methodology that acknowledges the importance of narrative, context, and culture was devised to explore how anger as an emotion is understood and experienced by a group of Indigenous men in a South Australian prison. Although some of the major themes reflected experiences of anger common to many offenders, it was evident that for these Indigenous men, anger was experienced within a broad social and political context that imbued the experience of anger with layers of culturally specific meaning. It is suggested that these layers of meaning constitute sufficient difference to warrant further exploration