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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"

57 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. GRB 210411C: A very significant early X-ray afterglow
  5. GRB 190114C: East Asia VLBI Network observations
  6. GRB 190114C: photometric detection of a SN component
  7. GRB 190114C: JCMT SCUBA-2 sub-mm observations
  8. GRB 190114C: Optical follow-up from HCT
  9. GRB 190114C: CHILESCOPE optical observations
  10. GRB 190114C: RTT150 optical observations
  11. GRB 190114C: GMRT detection at 1.26GHz
  12. GRB 190114C: MeerKAT radio observation
  13. GRB 190114C: UKIRT JHK observation (CORRECTIONS)
  14. GRB 190114C: UKIRT JHK observation continuation - steady fading?
  15. GRB 190114C: Sardinia Radio Telescope observations (CORRECTION)
  16. GRB 190114C: REM optical/NIR detection (CORRECTION)
  17. GRB 190114C: Sardinia Radio Telescope observations
  18. GRB 190114C: RATIR Optical and NIR Detections
  19. GRB 190114C: RT-22 detection at 36.8 GHz
  20. GRB 190114C: COATLI Optical Detection
  21. GRB 190114C: ePESSTO NTT optical observations
  22. GRB 190114C: Continued UKIRT JHK observation
  23. GRB 190114C: continued CHILESCOPE optical obs
  24. GRB190114C: ATCA detection of the radio afterglow
  25. GRB 190114C: Optical detection from HCT
  26. GRB 190114C: CHILESCOPE optical observations
  27. GRB 190114C: UKIRT JHK observation
  28. Konus-Wind observation of GRB 190114C
  29. The Swift-XRT WT mode spectrum of GRB190114C
  30. GRB 190114C: KMTNet optical observation
  31. GRB 190114C: LSGT optical observation
  32. GRB 190114C: REM optical/NIR detection
  33. GRB 190114C: ALMA detection of a fading mm counterpart
  34. GRB 190114C: Mondy optical observations
  35. GRB 190114C: VLA Detection
  36. GRB 190114C: Swift/UVOT Detection
  37. GRB 190114C: Swift-BAT refined analysis
  38. GRB 190114C: Optical observations
  39. GRB 190114C:Insight-HXMT/HE detection
  40. GRB 190114C: A type 1 BdHN with TeV emission
  41. GRB 190114C: SPI-ACS/INTEGRAL extended emission detection
  42. GRB 190114C: AGILE/MCAL detection
  43. GRB 190114C: X-shooter observations of a highly extinguished afterglow
  44. GRB 190114C: Fermi-LAT detection
  45. GRB 190114C: refined redshift by the 10.4m GTC
  46. GRB 190114C: Fermi GBM detection
  47. GRB 190114C: Swift-XRT refined Analysis
  48. GRB 190114C: Enhanced Swift-XRT position
  49. GRB 190114C: GROND detection of the afterglow
  50. MAGIC detects the GRB 190114C in the TeV energy domain
  51. CORRECTED TARGET NAME: GRB 190114C: Planned XMM-Newton observation
  52. GRB 190114C: OASDG optical observations
  53. GRB 190114C: NOT optical counterpart and redshift
  54. GRB 190114C: MASTER 4-polarizations filters OT detection
  55. GRB 190114C: Possible host galaxy in Pan-STARRS
  56. GRB 190114C: MASTER afterglow Detection
  57. GRB 190114C: Swift detection of a very bright burst with a bright optical counterpart

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