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Would it affect your opinion if the light emitted was noticed first by another project, who then told the gravitational wave people about it, at which point the

by nonbel 8y ago

Would it affect your opinion if the light emitted was noticed first by another project, who then told the gravitational wave people about it, at which point they found data their algorithms had previously rejected as noise and changed the classification to be a signal?

pwned1 8y ago
Yikes!
- nonbel 8y ago
  I don't know if its "yikes". But we are still waiting for them to detect something first and prove it is real by pointing where to look. I mean if you were waiting for that kind of evidence to begin with.
  - davidcuddeback 8y ago
    > But we are still waiting for them to detect something first and prove it is real by pointing where to look. That's exactly what happened with last year's neutron star merger. It was detected as GRB and GW, localized based off of the GW data, and then an observing campaign found a transient at the predicted location in visible light, IR, UV, radio, and X-ray.
davidcuddeback 8y ago
It was actually detected by two gravitational wave facilities (Hanford and Livingston) before the GRB was detected by Fermi. What you're referring to is that the gravitational wave was in a third facility's blind spot (Virgo). So yes, they had to dig it out of Virgo's data to triangulate the location of the signal so that they could confirm the event in optical wavelengths (which they did). No, that doesn't affect my opinion, because your characterization is inaccurate. It was in fact detected independently as a GW and a GWB.
- nonbel 8y ago
  >"On 2017 August 17 12:41:06 UTC the Fermi Gamma-ray Burst Monitor (GBM; Meegan et al. 2009) onboard flight software triggered on, classified, and localized a GRB. A Gamma-ray Coordinates Network (GCN) Notice (Fermi-GBM 2017) was issued at 12:41:20 UTC announcing the detection of the GRB, which was later designated GRB 170817A (von Kienlin et al. 2017). Approximately 6 minutes later, a gravitational-wave candidate (later designated GW170817) was registered in low latency (Cannon et al. 2012; Messick et al. 2017) based on a single-detector analysis of the Laser Interferometer Gravitational-wave Observatory (LIGO) Hanford data. The signal was consistent with a BNS coalescence with merger time, tc, 12:41:04 UTC, less than 2 s before GRB 170817A. A GCN Notice was issued at 13:08:16 UTC. Single-detector gravitational-wave triggers had never been disseminated before in low latency. Given the temporal coincidence with the Fermi-GBM GRB, however, a GCN Circular was issued at 13:21:42 UTC (LIGO Scientific Collaboration & Virgo Collaboration et al. 2017a) reporting that a highly significant candidate event consistent with a BNS coalescence was associated with the time of the GRB959 ." http://iopscience.iop.org/article/10.3847/2041-8213/aa91c9 http://iopscience.iop.org/article/10.3847/2041-8213/aa91c9
  - dogma1138 8y ago
    Both LIGO detectors detected and classified it as GW event at the same time as the GRB classification then it was confirmed through VIRGO data and localized. https://www.ligo.caltech.edu/page/press-release-gw170817 https://www.ligo.caltech.edu/page/press-release-gw170817 Gravitational waves are all candidates until they can be confirmed with external sources.
    - nonbel 8y ago
      >"Both LIGO detectors detected and classified it as GW event at the same time as the GRB classification then it was confirmed through VIRGO data and localized." All I can say is that other source clearly describes that the Fermi team announced detection of a gamma ray burst well beforehand, and that the ligo team treated the situation as exceptional due to that announcement. >"Gravitational waves are all candidates until they can be confirmed with external sources." My understanding is that there is expected to be no accompanying external evidence for waves generated by inspiraling black holes.

by nonbel 8y ago

pwned1 8y ago

Yikes!

nonbel 8y ago
I don't know if its "yikes". But we are still waiting for them to detect something first and prove it is real by pointing where to look. I mean if you were waiting for that kind of evidence to begin with.
- davidcuddeback 8y ago
  > But we are still waiting for them to detect something first and prove it is real by pointing where to look. That's exactly what happened with last year's neutron star merger. It was detected as GRB and GW, localized based off of the GW data, and then an observing campaign found a transient at the predicted location in visible light, IR, UV, radio, and X-ray.

davidcuddeback 8y ago

It was actually detected by two gravitational wave facilities (Hanford and Livingston) before the GRB was detected by Fermi. What you're referring to is that the gravitational wave was in a third facility's blind spot (Virgo). So yes, they had to dig it out of Virgo's data to triangulate the location of the signal so that they could confirm the event in optical wavelengths (which they did). No, that doesn't affect my opinion, because your characterization is inaccurate. It was in fact detected independently as a GW and a GWB.

nonbel 8y ago
>"On 2017 August 17 12:41:06 UTC the Fermi Gamma-ray Burst Monitor (GBM; Meegan et al. 2009) onboard flight software triggered on, classified, and localized a GRB. A Gamma-ray Coordinates Network (GCN) Notice (Fermi-GBM 2017) was issued at 12:41:20 UTC announcing the detection of the GRB, which was later designated GRB 170817A (von Kienlin et al. 2017). Approximately 6 minutes later, a gravitational-wave candidate (later designated GW170817) was registered in low latency (Cannon et al. 2012; Messick et al. 2017) based on a single-detector analysis of the Laser Interferometer Gravitational-wave Observatory (LIGO) Hanford data. The signal was consistent with a BNS coalescence with merger time, tc, 12:41:04 UTC, less than 2 s before GRB 170817A. A GCN Notice was issued at 13:08:16 UTC. Single-detector gravitational-wave triggers had never been disseminated before in low latency. Given the temporal coincidence with the Fermi-GBM GRB, however, a GCN Circular was issued at 13:21:42 UTC (LIGO Scientific Collaboration & Virgo Collaboration et al. 2017a) reporting that a highly significant candidate event consistent with a BNS coalescence was associated with the time of the GRB959 ." http://iopscience.iop.org/article/10.3847/2041-8213/aa91c9 http://iopscience.iop.org/article/10.3847/2041-8213/aa91c9
- dogma1138 8y ago
  Both LIGO detectors detected and classified it as GW event at the same time as the GRB classification then it was confirmed through VIRGO data and localized. https://www.ligo.caltech.edu/page/press-release-gw170817 https://www.ligo.caltech.edu/page/press-release-gw170817 Gravitational waves are all candidates until they can be confirmed with external sources.
  - nonbel 8y ago
    >"Both LIGO detectors detected and classified it as GW event at the same time as the GRB classification then it was confirmed through VIRGO data and localized." All I can say is that other source clearly describes that the Fermi team announced detection of a gamma ray burst well beforehand, and that the ligo team treated the situation as exceptional due to that announcement. >"Gravitational waves are all candidates until they can be confirmed with external sources." My understanding is that there is expected to be no accompanying external evidence for waves generated by inspiraling black holes.