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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"

675 results found.

  1. GRB 081118: GROND detection of afterglow
  2. GRB 081109: GROND redshift limit and host extinction
  3. GRB 081109: GROND Detection of the Optical/NIR Afterglow Candidate
  4. GRB 081104: GROND found no Optical/NIR Afterglow
  5. GRB 081105: GROND Upper Limits
  6. GRB 081104: GROND Detection of the Optical/NIR Afterglow Candidate?
  7. GRB 081028: GROND Confirmation of the Optical/NIR Afterglow
  8. GRB 081029: GROND Detection of the Optical/NIR Afterglow
  9. GRB 081028: GROND Detection of the Optical/NIR Afterglow Candidate
  10. GRB 081012: GROND upper limits
  11. GRB 080928: Watcher observations
  12. GRB 080928: VLT redshift
  13. GRB 080928: GROND DETECTION
  14. GRB 080916C: GROND Confirmation of the Optical Afterglow
  15. GRB 080916C: GROND Confirmation of the Optical Afterglow
  16. GRB 080915A: GROND upper limits
  17. GRB 080916A: GROND lightcurve
  18. GRB 080916C: GROND Detection of the Optical Afterglow Candidate
  19. GRB 080913: VLT/FORS spectrum
  20. GRB 080913: GROND photo-z
  21. GRB 080913: GROND observation of a high-z optical/NIR afterglow candidate
  22. GRB 080906: GROND observations of the optical/NIR afterglow
  23. GRB 080723B: GROND upper limits
  24. GRB 080805: Faulkes Telescope South optical observations
  25. GRB 080804: GROND observations
  26. GRB 080805: VLT redshift
  27. GRB 080805: GROND detection of possible afterglow
  28. GRB 080727B: KAIT photometry and an early lightcurve break
  29. GRB 080727B: GROND redshift limit
  30. GRB 080714: GROND confirmation of the optical/NIR afterglow
  31. GRB 080707: GROND Confirmation of the Optical Afterglow
  32. UVOT observations of GRB080707
  33. GRB 080707: GROND Detection of the Optical Afterglow Candidate
  34. GRB 080703: GROND Upper Limits
  35. GRB 080702B: GROND Upper Limits
  36. GRB 080623: GROND upper limits
  37. GRB 080613A: Swift-XRT detection of the afterglow
  38. GRB 080613A: GROND Confirmation of the Afterglow Candidate
  39. GRB 080613B: GROND Upper Limits
  40. GRB 080605: TLS 3rd Epoch - Source Confusion
  41. GRB 080605: GROND 2nd epoch observations
  42. GRB 080605: GROND detection of the optical afterglow candidate
  43. GRB 80516: Swift/UVOT Observations
  44. GRB 080520: VLT redshift
  45. GRB 080520, GROND observations
  46. GRB 080516, GROND further analysis
  47. GRB 080516, GROND 2nd epoch observations
  48. GRB 080516, GROND observations
  49. GRB 080514B: slow fading behaviour ?
  50. GRB 080514B, GROND observations
  51. GRB080413B
  52. GRB 080413B: GROND detection of afterglow in all bands
  53. GRB 080411: Swift/UVOT refined analysis
  54. GRB 080411: GROND detection of optical afterglow candidate
  55. GRB 080408: GROND detection of optical/NIR afterglow candidate
  56. GRB 080330: GROND Observations
  57. GRB 080325: GROND Observations
  58. GRB 080319D: GROND Detection of the Optical Counterpart
  59. GRB 080319D: GROND Observations
  60. GRB 080218B: GROND upper limits
  61. GRB 080212: REM refined analysis
  62. GRB 080212: GROND detects afterglow
  63. GRB 080207: VLT NIR early upper limits
  64. GRB 080210: VLT redshift
  65. GRB 080210: GOND detection in all bands and redshift upper limit
  66. GRB 080207: GROND upper limits
  67. GRB 080129: GROND detection in all bands, and fading
  68. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  69. GRB 080120: GROND confirmation of the optical afterglow
  70. GRB 080120: GROND detection
  71. GRB 071031: GROND detection in all bands
  72. GRB 070802: GROND J band candidate
  73. GRB 070628: NIR detection of afterglow
  74. GROND upper limits of GRB 070521
  75. GRB 070509: objects inside XRT error circle

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