Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

37580 results found.

  1. GRB 240817A: Fermi GBM Final Real-time Localization
  2. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  3. IBAS Alert n.10856: not a GRB
  4. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  5. EP240816b: KAIT optical upper limit
  6. GRB 240814B: GRBAlpha detection
  7. Fermi trigger No 745501396: Global MASTER-Net observations report
  8. Fermi GRB 240814A: Global MASTER-Net observations report
  9. Fermi GRB 240814C: Global MASTER-Net observations report
  10. Fermi trigger No 745306088: Global MASTER-Net observations report
  11. GRB 240814C: Fermi GBM Final Real-time Localization
  12. Fermi GRB 240814B: Global MASTER-Net observations report
  13. GRB 240812B: SVOM/GRM observation
  14. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  15. GRB 240814B: Fermi GBM Final Real-time Localization
  16. GRB 240814A: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 745220784: Global MASTER-Net observations report
  18. Konus-Wind detection of GRB 240811A
  19. Konus-Wind detection of GRB 240810A
  20. Fermi Gamma-ray Burst Monitor trigger 745220784/240813240 is not a GRB
  21. GRB 240809A: Correction to the VLA source position in GCN 37158
  22. GRB 240810A: SVOM/GRM observation
  23. Fermi Gamma-ray Burst Monitor trigger 240812940/745194848 is not a GRB
  24. Fermi Gamma-ray Burst Monitor trigger 240812917/745192855 is not a GRB
  25. Fermi Gamma-ray Burst Monitor trigger 240812917/745192855 is not a GRB
  26. GRB 240809A: ATA radio non-detection
  27. GRB 240812D: Fermi GBM Final Real-time Localization
  28. GRB 240812C: Fermi GBM Final Real-time Localization
  29. GRB 240809A : RAPAS follow-up observations
  30. GRB 240809A: VLA detection
  31. GRB 240809A: ALMA detection
  32. IPN triangulation of GRB 240810A (short)
  33. GRB 240811A: Swift-BAT refined analysis
  34. GRB 240809A: Swift-BAT refined analysis
  35. GRB 240812B: AstroSat CZTI detection of a long burst
  36. GRB 240811A: Bassano Bresciano Observatory upper limit
  37. GRB 240811A: Swift-XRT refined Analysis
  38. Fermi Gamma-ray Burst Monitor trigger 745135620/240812255 is not a GRB
  39. GRB 240811A: Swift/UVOT Upper Limits
  40. EP240801a: Assy-Turgen optical observations
  41. Fermi GRB 240810A: Global MASTER-Net observations report
  42. Fermi Gamma-ray Burst Monitor trigger 240812094/745121685 is not a GRB
  43. GRB 240812A: Fermi GBM Final Real-time Localization
  44. GRB 240811A: LCOGT Optical Upper Limit
  45. GRB 240811A: Enhanced Swift-XRT position
  46. GRB 240811A: Upper limits with Mephisto
  47. Konus-Wind detection of GRB 240809A
  48. Fermi trigger No 745057312: Global MASTER-Net observations report
  49. Swift GRB 240811A: Global MASTER-Net observations report
  50. GRB 240811A: Swift detection of a burst
  51. Fermi Gamma-ray Burst Monitor trigger 745050426/240811269 is not a GRB
  52. GRB 240810A: Fermi GBM Final Real-time Localization
  53. GRB 240809A: REM detection of the optical afterglow
  54. GRB 240809A: Bassano Bresciano Observatory optical observations
  55. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  56. GRB 240809A: Conclusive redshift from VLT
  57. Fermi-LAT gamma-ray observations of IceCube-240808A
  58. GRB 240809A: KAIT optical observations
  59. GRB 240808A: AstroSat CZTI detection
  60. GRB 240809A: GIT afterglow observations
  61. GRB 240809B: MAXI/GSC detection
  62. GRB 240809A: Swift/UVOT Detection
  63. GRB 240809A: Tentative redshift from NOT
  64. GRB 240809A: Swift-XRT refined Analysis
  65. IPN triangulation of GRB 240807A / EP 240807a
  66. Swift GRB 240809A: Global MASTER-Net observations report
  67. GRB 240809A: JinShan optical observations
  68. GRB 240809A: Enhanced Swift-XRT position
  69. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  70. GRB 240809A: SVOM/GRM observation
  71. GRB 240808A: SVOM/GRM observation
  72. GRB 240807A: SVOM/GRM observation
  73. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  74. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  75. EP240807a: STEP/T80S optical limits
  76. GRB 240807B: AstroSat CZTI detection of a short burst
  77. IceCube-240808A - IceCube observation of a high-energy neutrino candidate track-like event
  78. GRB 240801A: GRBAlpha detection
  79. GRB 240807B: Fermi GBM Final Localization
  80. GRB 240710B: VZLUSAT-2 detection
  81. GRB 240805A: ATCA Radio Upper Limits
  82. Fermi trigger No 744761058: Global MASTER-Net observations report
  83. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  84. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  85. EP240802a/GRB240802A: KAIT optical upper limit
  86. GRB 240720B: VZLUSAT-2 detection
  87. GRB 240710A: VZLUSAT-2 detection
  88. GRB 240807A: Fermi GBM Final Localization
  89. GRB 240805B: GIT optical upper limit
  90. EP240806a: KAIT optical observations
  91. GRB 240805B: Swift-BAT refined analysis
  92. GRB 240805A: Swift-BAT refined analysis
  93. Fermi trigger No 744629911: Global MASTER-Net observations report
  94. EP240804a (GRB 240804B): NOT optical observations
  95. Konus-Wind detection of GRB 240802A (EP240802a)
  96. Improved IPN triangulation of GRB 240802A / EP 240802a
  97. Konus-Wind detection of GRB 240805A
  98. GRB 240805B Bassano Bresciano Observatory upper limit
  99. GRB240805A: Fermi GBM Observation
  100. GRB 240805B: JinShan optical afterglow detection

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov