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"

36338 results found.

  1. GRB241105A: Gemini-South Optical Afterglow Detection
  2. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  3. GRB 241105A: Swift/UVOT Detection
  4. EP241101a: CrAO ZTSH optical observations
  5. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  6. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  7. GRB 241105A: BOOTES-7 optical detection
  8. GRB 241030A: Mondy optical observations
  9. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  10. Konus-Wind detection of GRB 241105A (short with extended emission)
  11. Konus-Wind detection of GRB 241021A
  12. GRB 241105A: SVOM/VT optical afterglow observations
  13. GRB 241105A: Swift-XRT afterglow detection
  14. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  15. GRB 241104A: Swift-XRT observations
  16. GRB 240511A: LCO upper limits
  17. GRB 241104A: Fermi GBM Observation
  18. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  19. GRB 241105A: Swift ToO observations
  20. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  21. GRB 241104A: Swift ToO observations
  22. GRB 241104A: NOT optical non-detection
  23. GRB 241105A: GOTO tentative optical counterpart candidate
  24. Fermi GRB 241105A: Global MASTER-Net observations report
  25. GRB 241104A: SVOM/VT optical candidate
  26. GRB 241105A: Fermi GBM Final Real-time Localization
  27. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  28. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  29. GRB 241104A: SVOM/GRM observation
  30. EP241104a: EP detection of GRB 241104A X-ray emission
  31. GRB 241010A: host galaxy redshift z = 0.977
  32. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  33. GRB 240821A: further radio observations with the VLA
  34. Fermi GRB 241104A: Global MASTER-Net observations report
  35. GRB 241104A: Fermi GBM Final Real-time Localization
  36. GRB 241030A: GRBAlpha detection
  37. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  38. GRB 241030A: Rapid release of TESS data.
  39. GRB 241029A: GRBAlpha detection
  40. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  41. Swift GRB 241101A: Global MASTER-Net observations report
  42. GRB 241101A: FRAM-ORM optical limit
  43. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  44. EP241021a: Upper limit from Konus-Wind observations
  45. GRB 241101A: Swift-BAT refined analysis
  46. GRB 241030A: further SAO RAS optical observations
  47. GRB 241030A: Optical Observations via Virtual Telescope Project
  48. GRB 241030B: Swift-XRT refined Analysis
  49. GRB 241026A: SAO RAS optical observations
  50. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  51. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  52. GRB 241101A: Swift detection of a burst
  53. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  54. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  55. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  56. GRB 241030B: Montarrenti Observatory optical upper limit
  57. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  58. GRB 241030A: SAO RAS optical observations
  59. GRB 241030A: Fermi GBM Observation
  60. GRB 241030B : GIT optical upper limits
  61. GRB 241030B: LCOGT Optical Upper Limits
  62. GRB 241030B: Swift-BAT refined analysis
  63. GRB 241030A: Swift-BAT refined analysis
  64. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  65. GRB 241030B: Swift/UVOT Detection
  66. GRB 241029A: LCO optical detection
  67. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  68. GRB 241030B: SVOM/GRM observation
  69. GRB 241030B : MITSuME Akeno optical upper limits
  70. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  71. GRB 241030B: SVOM/VT optical afterglow observations
  72. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  73. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  74. GRB241030B: Fermi GBM Observation
  75. GRB 241030B: BTA observations
  76. GRB 241029A: SVOM/VT optical afterglow observations
  77. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  78. GRB 241030B: Enhanced Swift-XRT position
  79. GRB 241030B: optical observations from the INAF Asiago Observatory
  80. GRB241030B: GRANDMA/TAROT Upper Limit
  81. GRB 241030A: Swift-XRT refined Analysis
  82. GRB 241030B: SAO RAS optical observations
  83. GRB 241030B: AKO Optical Afterglow Detection
  84. GRB 241030B: Nanshan/HMT optical afterglow detection
  85. GRB 241030B: SVOM/ECLAIRs detection of a burst
  86. GRB 241030B: Prompt enhanced Swift-XRT position
  87. Konus-Wind detection of GRB 241030A
  88. GRB 241030B: Swift detection of a burst
  89. GRB 241030B: Fermi GBM Final Real-time Localization
  90. GRB 241030A: Fermi-LAT detection
  91. GRB 240912A: radio detection with the VLA
  92. Fermi GRB 241030A: Global MASTER-Net observations report
  93. GRB 241030A: AKO Optical Afterglow Detection
  94. Swift GRB 241030A: Global MASTER-Net observations report
  95. GRB 241030A: Swift/UVOT Detection
  96. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  97. GRB 241030A: SVOM/GRM observation
  98. GRB 241026A: Swift-BAT refined analysis
  99. GRB 241030A: SVOM/C-GFT optical observations
  100. GRB 241026A: LBT optical observations

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