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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

33 results found.

  1. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  2. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  3. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  4. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  5. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  6. LIGO/Virgo S190408an: ATLAS observations of the S190412m skymap
  7. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  8. LIGO/Virgo S190408an: GROND Observations of MASTER OT J154209.55-431742.2
  9. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  10. LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
  11. LIGO/Virgo S190408an: MAXI/GSC Observations
  12. LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
  13. LIGO/Virgo S190408an: CALET Observations
  14. LIGO/Virgo S190408an: TMTS Optical Observation
  15. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  16. LIGO/Virgo S190408an: HMT optical observations
  17. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  18. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  19. LIGO/Virgo S190408an: SAGUARO follow-up observations
  20. LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
  21. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  22. LIGO/Virgo S190408an: MASTER OT detection
  23. LIGO/Virgo S190408an: Swift/BAT data search
  24. LIGO/Virgo S190408an: KMTNet observation
  25. LIGO-Virgo S190408an: AGILE GRID observations
  26. LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
  27. LIGO/Virgo S190408an: Identification of a GW binary merger candidate
  28. Search for neutrino counterparts to GW candidate S190408an with IceCube
  29. LIGO-Virgo S190408an: HAWC follow-up
  30. INTEGRAL observation of S190408an
  31. LIGO/Virgo S190408an: Fermi GBM Observation
  32. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  33. LIGO-Virgo S190408an: AGILE MCAL observations

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