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"

21056 results found.

  1. EP240625a: GRANDMA Optical Upper Limits
  2. EP240626a: EP-WXT detection of a fast X-ray transient
  3. Fermi GRB 240625B: Global MASTER-Net observations report
  4. EP240625a: NOT optical counterpart candidate
  5. EP240625a: EP-WXT detection of a fast X-ray transient
  6. Swift GRB 240624A: Global MASTER-Net observations report
  7. GRB240615A: Gemini-North observations of the BAT and XRT positions
  8. Fermi GRB 240624A: Global MASTER-Net observations report
  9. Fermi trigger No 740949590: Global MASTER-Net observations report
  10. GRB240615A: Gemini-North observations of the BAT and XRT positions
  11. GRB 240619A: detection of a radio counterpart with AMI-LA
  12. EP240618a: NOT further optical observations
  13. GRB 240619A: J-band detection with WINTER
  14. Fermi trigger No 740744838: Global MASTER-Net observations report
  15. EP240618a: NOT optical counterpart candidate
  16. GRB 240529A: JinShan optical observations
  17. EP240618a: GSP optical upper limit
  18. EP240617a: tentative Swift/XRT detection of the afterglow
  19. GRB 240619A: Swift-XRT probable afterglow detection
  20. GRB 240619A: Swift ToO observations
  21. GRB 240619A: GOTO candidate optical afterglow
  22. EP240618a: Abastumani optical observationsEP240618a
  23. GRB 240615A: NOT optical observations
  24. EP240618a: GRANDMA Optical Upper Limits
  25. EP240618a: TRT optical upper limit
  26. Fermi trigger No 740474239: Global MASTER-Net observations report
  27. Fermi GRB 240619A: Global MASTER-Net observations report
  28. EP240617a: STEP/T80S optical limits
  29. GRB 240615A: possible transient detection from Wendelstein observations
  30. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  31. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  32. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  33. Fermi trigger No 740430582: Global MASTER-Net observations report
  34. EP240617a: EP-WXT detection of a fast X-ray transient
  35. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  36. GRB 240615A: J-band upper limits from WINTER
  37. GRB 240615A: Swift-XRT observations
  38. X-ray transient EP240414a: Chandra late time observation
  39. Fermi trigger No 740221779: Global MASTER-Net observations report
  40. Fermi GRB 240616A: Global MASTER-Net observations report
  41. GRB 240615A: GOTO optical upper limits
  42. Fermi trigger No 740166710: Global MASTER-Net observations report
  43. GRB 240615A: Swift ToO observations
  44. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  45. Fermi GRB 240612B: Global MASTER-Net observations report
  46. Fermi GRB 240612A: Global MASTER-Net observations report
  47. Fermi GRB 240611A: Global MASTER-Net observations report
  48. GRB 240529A: LBT optical detection and late temporal decay
  49. Trigger 1236151: Swift detection of EXO 0748-676
  50. Fermi GRB 240610A: Global MASTER-Net observations report
  51. Fermi trigger No 739632045: Global MASTER-Net observations report
  52. Fermi GRB 240608A: Global MASTER-Net observations report
  53. Fermi trigger No 739506569: Global MASTER-Net observations report
  54. Fermi GRB 240607A: Global MASTER-Net observations report
  55. GRB 240529A: NOEMA detection
  56. GRB 240607A: Fermi GBM detection of a very bright burst
  57. GRB 240529A: radio detection with AMI-LA
  58. Fermi trigger No 739373591: Global MASTER-Net observations report
  59. GRB 240606B: Swift-XRT afterglow detection
  60. Swift GRB240606.15: Global MASTER-Net observations report
  61. GRB 240606B: Swift ToO observations
  62. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  63. Fermi GRB 240604A: Global MASTER-Net observations report
  64. Fermi GRB 240605A: Global MASTER-Net observations report
  65. Fermi GRB 240605C: Global MASTER-Net observations report
  66. GRB 240529A: SAO RAS optical observations
  67. Fermi GRB 240603C: Global MASTER-Net observations report
  68. GRB 240529A: MASTER prompt OT detection
  69. GRB 240529A: continued SAO RAS optical observations
  70. Fermi GRB 240602A: Global MASTER-Net observations report
  71. GRB 240529A: OSN optical detection
  72. GRB 240529A: further SAO RAS optical observations
  73. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  74. LXT 240528A: GSP optical upper limit
  75. GRB 240529A: 1.3m DFOT Optical observations
  76. GRB 240529A : Mondy optical observations
  77. GRB 240529A: SAO RAS optical observations
  78. GRB 240529A: optical photometry from Konkoly
  79. GRB 240529A: T193/MISTRAL observations
  80. GRB 240529A: AKO Optical Afterglow Detection
  81. GRB 240529A: J-band detections with WINTER
  82. GRB 240529A: Skynet Optical Observations
  83. LXT 240528A: LEIA detection of a fast X-ray transient
  84. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  85. GRB 240529A: Swift/UVOT Detection
  86. GRB 240529A: NOT optical observations
  87. GRB 240529A: GOTO optical afterglow detection
  88. GRB 240527B: Swift-XRT afterglow detection
  89. Swift GRB240529.12: Global MASTER-Net observations report
  90. Fermi GRB 240527A: Global MASTER-Net observations report
  91. LAT GRB240527.59: Global MASTER-Net observations report
  92. Fermi GRB 240527B: Global MASTER-Net observations report
  93. Fermi trigger No 738348224: Global MASTER-Net observations report
  94. Fermi trigger No 738330463: Global MASTER-Net observations report
  95. GRB 240513A: Swift-XRT afterglow detection
  96. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  97. Fermi trigger No 737996942: Global MASTER-Net observations report
  98. EP240518a: GSP optical upper limit
  99. GRB 240516A: Swift/UVOT Upper Limits
  100. Fermi trigger No 737788024: Global MASTER-Net observations report

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