The Laser That Helped Detect Gravitational Waves

Numerical-relativity simulations of the first binary black-hole merger observed by the Advanced LIGO detector on September 14, 2015 (Source: S. Ossokine, A. Buonanno, AEI / D. Steinhauser, Airb. Hydro Mapp.)

Numerical-relativity simulations of the first binary black-hole merger observed by the Advanced LIGO detector on September 14, 2015 (Source: S. Ossokine, A. Buonanno, AEI / D. Steinhauser, Airb. Hydro Mapp.)

An international researcher team of the LIGO Scientific Collaboration, the Albert Einstein Institute Hannover, AEI, and many other institutions have proven Albert Einstein’s theory of general relativity 100 years after its development: they succeeded in recording the merger of two black holes. The resulting gravitational wave was measured in September 2015 by both LIGO detectors, located in Livingston, Louisiana, and Hanford, Washington, USA; yesterday, the evaluation of the data was published and presented to the world press.

For more than ten years, the AEI and the Laser Zentrum Hannover e.V., LZH, have put R&D efforts into the development of laser systems for the detectors of the Laser Interferometer Gravitational-wave Observatory, LIGO . The lasers were jointly manufactured and integrated into the US observatories as a ready-to-run system by the LZH, the AEI and the LZH spin-off company neoLASE. The gravitational wave detected now was recorded by the Enhance LIGO model, eLIGO.

Installation of the LZH lasers in the LIGO cleanroom, Livingston, Louisiana. (Source: LZH)

Installation of the LZH lasers in the LIGO cleanroom, Livingston, Louisiana. (Source: LZH)

The Advanced LIGO systems that were put into operation in the meantime have a five times higher output power compared to the previous lasers. Under these circumstances, chances to detect further gravitational waves are significantly higher. With this high-tech measurement instrument, a reliable basis was created for future research in gravitational physics in Hannover and worldwide.

The German researchers also made crucial contributions to the discovery in development and operation of extremely sensitive detectors, efficient data analysis methods running on powerful computer clusters, and highly accurate waveform models to detect the signal and infer astrophysical information from it. In the GEO collaboration together with UK colleagues, they designed and operate the GEO600 gravitational-wave detector near Hannover, Germany, a think tank and testbed for advanced detector techniques. Most of the key technologies that contributed to the unprecedented sensitivity of aLIGO and enabled the discovery have been developed and tested here. Examples of these are signal recycling, resonant sideband extraction, and the monolithic mirror suspensions. (Sources: LZH / AEI)

Reference: B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration): Observation of Gravitational Waves from a Binary Black Hole Merger, Phys. Rev. Lett. 116, 061102 (2016); DOI: 10.1103/PhysRevLett.116.061102

Links: Laser Development Dept. (J. Neumann), Laser Zentrum Hannover e.V., Hannover, GermanyGEO Collaboration

 

Speak Your Mind

*