Steven J. Berukoff

The GEO 600 gravitational wave detector

The GEO 600 laser interferometer with 600 m armlength is part of a worldwide network of gravitational wave detectors. Due to the use of advanced technologies like multiple pendulum suspensions with a monolithic last stage and signal recycling, the anticipated sensitivity of GEO 600 is close to the initial sensitivity of detectors with several kilometres armlength. This paper describes the subsystems of GEO 600, the status of the detector by September 2001 and the plans towards the first science run.

Status of the GEO600 detector

Of all the large interferometric gravitational-wave detectors, the German/British project GEO600 is the only one which uses dual recycling. During the four weeks of the international S4 data-taking run it reached an instrumental duty cycle of 97% with a peak sensitivity of 7 × 10−22 Hz−1/2 at 1 kHz. This paper describes the status during S4 and improvements thereafter.

The status of GEO 600

The GEO 600 laser interferometer with 600m armlength is part of a worldwide network of gravitational wave detectors. GEO 600 is unique in having advanced multiple pendulum suspensions with a monolithic last stage and in employing a signal recycled optical design. This paper describes the recent commissioning of the interferometer and its operation in signal recycled mode.

Commissioning, characterization and operation of the dual-recycled GEO 600

The German-British laser-interferometric gravitational-wave detector GEO 600 is currently being commissioned as part of a worldwide network of gravitational-wave detectors. GEO 600 recently became the first kilometre-scale interferometer to employ dual recycling-an optical configuration that combines power recycling and signal recycling. We present a brief overview of the commissioning of this dual-recycled interferometer, the performance results achieved during a subsequent extended data-taking period, and the plans intended to bring GEO 600 to its final configuration.

The Status of GEO600

The GEO 600 laser interferometer with 600m armlength is part of a worldwide network of gravitational wave detectors. GEO 600 is unique in having advanced multiple pendulum suspensions with a monolithic last stage and in employing a signal recycled optical design. This paper describes the recent commissioning of the interferometer and its operation in signal recycled mode.

A report on the status of the GEO 600 gravitational wave detector

GEO 600 is an interferometric gravitational wave detector with 600 m arms, which will employ a novel, dual-recycled optical scheme allowing its optical response to be tuned over a range of frequencies (from ~100 Hz to a few kHz). Additional advanced technologies, such as multiple pendulum suspensions with monolithic bottom stages, make the anticipated sensitivity of GEO 600 comparable to initial detectors with kilometre arm lengths. This paper discusses briefly the design of GEO, reports on the status of the detector up to the end of 2002 with particular focus on participation in coincident engineering and science runs with LIGO detectors. The plans leading to a fully optimized detector and participation in future coincident science runs are briefly outlined.

Data acquisition and detector characterization of GEO600

The data acquisition system of the gravitational wave detector GEO600 is recording the first data now. Data from detector subsystems and environmental channels are being acquired. The data acquisition system is described and first results from the detector characterization work are being presented. We analysed environmental influences on the detector to determine noise propagation through the detector. Long-term monitoring allowed us to see long-timescale drifts in subsystems.

Petascale cyberinfrastructure for ground-based solar physics: approach of the DKIST data center

The Daniel K Inouye Solar Telescope, under construction in Maui, is designed to perform high-resolution spectropolarimetric visible and infrared measurements of the Sun, and will annually produce 3 PB of data, via 5x108 images and 2x1011 metadata elements requiring calibration, long-term data management, and open and free distribution. After briefly describing the DKIST and its instrument suite, we provide an overview of functions that the DKIST Data Center will provide, and focus on major challenges in its development. We conclude by discussing approach and mention some technologies that the Data Center team is using to develop a petascale computational and data storage resource to support this unique world-class DKIST facility and support its long-term scientific and operational goals.

Revisiting software specification and design for large astronomy projects

The separation of science and engineering in the delivery of software systems overlooks the true nature of the problem being solved and the organization that will solve it. Use of a systems engineering approach to managing the requirements flow between these two groups as between a customer and contractor has been used with varying degrees of success by well-known entities such as the U.S. Department of Defense. However, treating science as the customer and engineering as the contractor fosters unfavorable consequences that can be avoided and opportunities that are missed. For example, the “problem” being solved is only partially specified through the requirements generation process since it focuses on detailed specification guiding the parties to a technical solution. Equally important is the portion of the problem that will be solved through the definition of processes and staff interacting through them. This interchange between people and processes is often underrepresented and under appreciated. By concentrating on the full problem and collaborating on a strategy for its solution a science-implementing organization can realize the benefits of driving towards common goals (not just requirements) and a cohesive solution to the entire problem. The initial phase of any project when well executed is often the most difficult yet most critical and thus it is essential to employ a methodology that reinforces collaboration and leverages the full suite of capabilities within the team. This paper describes an integrated approach to specifying the needs induced by a problem and the design of its solution.

Detector characterization in GEO 600

The GEO 600 interferometric gravitational wave detector conducted its first science run (S1) from 23 August 2002 to 9 September 2002. The GEO 600 data acquisition system is described together with some software tools developed for doing detector characterization and data analysis. Detector characterization results are also being presented.