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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

7 results found.

  1. LIGO/Virgo/KAGRA S231113bw: Updated Sky localization, EM Bright Classification, and Source Classification
  2. LIGO/Virgo/KAGRA S231113bw: Zwicky Transient Facility observations
  3. LIGO/Virgo/KAGRA S231113bw: GROWTH-India coverage and upper limits
  4. LIGO/Virgo S231113bw: upper limits from AGILE/MCAL
  5. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  6. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  7. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate


Download all Circulars as a .tar.gz archive:
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