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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').

33 results found.

  1. GRB 221009A: Determination of the black holes mass and spin
  2. GRB 221009A: Peak luminosity of the supernova vs. synchrotron afterglow
  3. GRB 221009A X-ray light-curve and the indication of TeV light-curve
  4. GMRT radio detection of GRB 180720B
  5. GRB 180720B: CALET Gamma-Ray Burst Monitor detection
  6. NuSTAR observations of GRB 180720B
  7. GRB 180720B: OAJ optical observations
  8. GRB 180720B: AMI-LA 15.5 GHz observation
  9. GRB 180720B long follow up requested
  10. GRB 180720B: KAIT Optical Observations
  11. GRB 180720B: D50 optical observations
  12. GRB 180720B: MASTER Global Net OT observations
  13. GRB 180720B: REM photometry
  14. GRB 180720B: ISON-Castelgrande optical observations
  15. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  16. GRB 180720B: COATLI Optical Detection
  17. Konus-Wind observation of GRB 180720B
  18. GRB 180720B: MITSuME Ishigaki optical observations
  19. GRB 180720B: Swift-BAT refined analysis
  20. GRB 180720B: VLT/X-shooter redshift
  21. GRB 180720B: MAXI/GSC detection
  22. GRB 180720B: LCO optical afterglow observations
  23. GCN 22984 was for GRB 180720B
  24. GRB 180720B: OSN detection, fading slower?
  25. GRB 180720B: Swift-XRT refined Analysis
  26. GRB 180720B: MITSuME Akeno optical observations
  27. GRB 180720B: Fermi GBM observation
  28. GRB 180720B : Fermi-LAT detection
  29. GRB 180720B : TSHAO optical observations
  30. GRB 180720B: Kanata 1.5m optical/NIR observation
  31. GRB 180720B: LCO Haleakala possible bright optical candidate
  32. Correction: Swift trigger #848890 is GRB 180720B (not GRB 180720A)
  33. GRB 180720B: Swift detection of a burst

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