Search for gravitational waves associated with the InterPlanetary Network short gamma ray bursts

We outline the scientific motivation behind a search for gravitational waves associated with short gamma ray bursts detected by the InterPlanetary Network (IPN) during LIGO's fifth science run and Virgo's first science run. The IPN localisation of short gamma ray bursts is limited to extended error boxes of different shapes and sizes and a search on these error boxes poses a series of challenges for data analysis. We will discuss these challenges and outline the methods to optimise the search over these error boxes.Comment: Methods paper; Proceedings for Eduardo Amaldi 9 Conference on Gravitational Waves, July 2011, Cardiff, U

Towards defining persistent critical illness and other varieties of chronic critical illness

We hypothesise that there exists a substantial and growing group of “persistently critically ill” patients who appear to be intensive care unit-dependent because of a cascade of critical illnesses rather than their original ICU admitting diagnosis. These persistently critically ill patients are those who remain in the ICU because of ongoing complications of care that continue after their reason for admission has been treated and is no longer active. We believe such patients can be distinguished from patients currently labelled as “chronic critical illness” or “prolonged mechanical ventilation”. We further believe that their primary problem is not simply failure to wean from mechanical ventilation due to muscle weakness and impaired gas exchange. We outline a program of clinician consultation, epidemiological research, consensus conference and validation to develop a useful definition of persistent critical illness, with the aim of supporting investigations in preventing persistence, and improving the care of patients so affected

Enhanced sensitivity of the LIGO gravitational wave detector by using squeezed states of light

Nearly a century after Einstein first predicted the existence of gravitational waves, a global network of Earth-based gravitational wave observatories1, 2, 3, 4 is seeking to directly detect this faint radiation using precision laser interferometry. Photon shot noise, due to the quantum nature of light, imposes a fundamental limit on the attometre-level sensitivity of the kilometre-scale Michelson interferometers deployed for this task. Here, we inject squeezed states to improve the performance of one of the detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) beyond the quantum noise limit, most notably in the frequency region down to 150 Hz, critically important for several astrophysical sources, with no deterioration of performance observed at any frequency. With the injection of squeezed states, this LIGO detector demonstrated the best broadband sensitivity to gravitational waves ever achieved, with important implications for observing the gravitational-wave Universe with unprecedented sensitivity