27 research outputs found

    Localization and broadband follow-up of the gravitational-wave transient GW150914

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    A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams

    All-sky search for gravitational-wave bursts in the second joint LIGO-Virgo run

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    We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration < 1 s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining this search with the previous LIGO-Virgo search on the data collected between November 2005 and October 2007. The upper limit on the rate of strong gravitational-wave bursts at the Earth is 1.3 events per year at 90% confidence. We also present upper limits on source rate density per year and Mpc^3 for sample populations of standard-candle sources. As in the previous joint run, typical sensitivities of the search in terms of the root-sum-squared strain amplitude for these waveforms lie in the range 5 10^-22 Hz^-1/2 to 1 10^-20 Hz^-1/2. The combination of the two joint runs entails the most sensitive all-sky search for generic gravitational-wave bursts and synthesizes the results achieved by the initial generation of interferometric detectors.Comment: 15 pages, 7 figures: data for plots and archived public version at https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=70814&version=19, see also the public announcement at http://www.ligo.org/science/Publication-S6BurstAllSky

    Observation of Gravitational Waves from a Binary Black Hole Merger

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    On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 × 10−21. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410þ160 −180 Mpc corresponding to a redshift z ¼ 0.09þ0.03 −0.04 . In the source frame, the initial black hole masses are 36þ5 −4M⊙ and 29þ4 −4M⊙, and the final black hole mass is 62þ4 −4M⊙, with 3.0þ0.5 −0.5M⊙c2 radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger

    Localization and broadband follow-up of the gravitational-wave transient GW150914

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    A gravitational-wave transient was identified in data recorded by the Advanced LIGO detectors on 2015 September 14. The event candidate, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the gravitational wave data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network Circulars, giving an overview of the participating facilities, the gravitational wave sky localization coverage, the timeline and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the electromagnetic data and results of the electromagnetic follow-up campaign will be disseminated in the papers of the individual teams

    Sharp force fatalities: suicide, homicide or accident? A series of 21 cases

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    Cases at study comprise 21 sharp force fatalities (9 suicides – 7mand 2 f; 8 homicides – 5mand 3 f; 2 accidental deaths – 1m and 1 f; 2 uncertain cases – 2 m), examined from 1993 to 2002. Suicide age range was 17–75 years, mean 42.4; in seven cases the age was upper 40. Scene of death was at home in six cases, at open place in two, during hospitalisation in one. Incised wounds were pre-eminent in suicides. Homicides showed multiple stab wounds. The two accidents were caused by ‘‘glassing’’. Uncertain cases were a small stab wound to the chest and an eviration. # 2004 Elsevier Ireland Ltd. All rights reserved

    Gunshot fatalities: suicide, homicide or accident? A series of 48 cases

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    Cases at study comprise 48 gunshot fatalities (33 suicides\u201429 males and 4 females; 12 homicides\u20148 males and 4 females; 3 uncertain cases\u20143 males), examined from 1992 to 2002. The age range of suicides is 22\u201396 years, mean 58.8 years. In 16 cases the age was upper 65. Scene of death was at home in 27 cases (of which 6 on bed), in a car in 2 cases and in an open place in 4 cases. Uncertain cases happened during hunting. The implements used in suicides were shotgun in 14 cases, rifles in 7, handguns in 11 and a humane veterinary killer in 1. In suicides single entrance wounds were found, apart 1 case with two entrance wounds. A script manifesting suicidal intent was present in 6 cases. Homicides showed both single and multiple entrance wounds: in the cases of multiple entrance wounds, no sign of contact/near contact injuries were seen. In 4 cases, bodies were hidden

    PARTO-ANALGESIA: ASPETTI MEDICO-LEGALI

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    Pain in labour is peculiar because it happens usually in helthy people, with a specific temporal sequence, and should be followed by wellness and gratification of birth. The possibilities of modern obstetric analgesia for humanization of birth, are in contrast with the idea that pain is a necessary companion of labour. Aims of obstetric analgesia are: wellbeing of mother and foetus, safety for woman and no complications for baby, without any diversion from a normal delivery. The elective epidural analgesia is an invasive technique with specific risks, and indications. The medico legal problems, we discuss in this work, are mainly information to give to the woman and consent validity, and duties and responsibilities of the operators and structure, considering laws and jurisprudence in Italy
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