`Bridging Gravitational Wave Astronomy and Observational Astrophysics', Proceedings of the 13th Gravitational Wave Data Analysis Workshop (GWDAW13) (San Juan, Puerto Rico, 19–22 January 2009), sponsored by the Center for Gravitational Wave Astronomy, the University of Texas at Brownsville and the National Astronomy and Ionosphere Center

Abstract

The 13th Gravitational Wave Data Analysis Workshop took place in San Juan, Puerto Rico on the 19–22 January 2009. This annual event has become the established venue for presenting and discussing new results and techniques in this crucial subfield of gravitational wave astronomy.A major attraction of the event is that scientists working with all possible instruments gather to discuss their projects and report on the status of their observations. The Center for Gravitational Wave Astronomy at the University of Texas at Brownsville, USA (a National Aeronautics and Space Administration University Research Center and a National Science Foundation Center for Research Excellence in Science and Technology) jointly with the National Astronomy and Ionosphere Center (which operates the Arecibo Observatory) were the proud sponsors of the gathering this time. As in previous years, GWDAW13 was well attended by more than 100 participants from over 10 countries worldwideAs this issue is going to press GEO, LIGO and VIRGO are undergoing new scientific runs of their instruments with the LIGO detectors holding the promise of increasing their operational sensitivity twofold as compared with the observations finished a couple of years ago.This new cycle of observations is a major milestone compared to the previous observations which have been accomplished. Gravitational waves have not been observed yet, but the instrumental sensitivity achieved has started producing relevant astrophysical results. In particular, very recently (Nature, 20 August 2009) a letter from the LIGO Scientific Collaboration http://www.ligo.org and the VIRGO Collaboration http://www.virgo.infn.it has set the most stringent limits yet on the amount of gravitational waves that could have come from the Big Bang in the gravitational wave frequency band where current gravitational wave detectors can observe. These results have put new constraints on the physical characteristics of the early universe.The proximity of a new era in observational astrophysics is sparking the interests of many astronomers who are looking at the potential that the ground-based interferometers (and eventually the space-based ones) have to complement the existing observational tools and future ones which use electromagnetic antennas and particle detectors. This potential was highlighted during this GWDAW meeting, which was organized under the title: `Bridging Gravitational Wave Astronomy and Observational Astrophysics'.One session within this conference was especially devoted to multi-messenger astronomy and the opportunities that will be afforded by conducting efforts based on the joint utilization of the new facilities made available to astronomers by key technological advances in existing and future satellite and ground-based facilities. The material presented in this issue is grouped into six different themes: data analysis articles related to the different sources modeled (un-modeled burst sources, coalescing compact binaries, and continuous waves), articles on data analysis aspects of observations with space-based detectors, articles on instrumental aspects of detection and articles on multi-messenger astronomy and astronomical observations complementary to gravitational wave antennas.The guest editors sincerely hope that this issue will become a useful reference for the field. We also want to thank especially the dedication and efforts of the local organizing committee, Paulo Freire and Murray Lewis from the Arecibo Observatory and Wanda Wiley from the CGWA at the University of Texas at Brownsville. Mario Díaz, Fredrick Jenet and Soumya Mohanty Center for Gravitational Wave Astronomy, The University of Texas at Brownsville Guest Editors