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"

36205 results found.

  1. GRB 241104A: Fermi GBM Final Real-time Localization
  2. GRB 241030A: GRBAlpha detection
  3. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  4. GRB 241030A: Rapid release of TESS data.
  5. GRB 241029A: GRBAlpha detection
  6. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  7. Swift GRB 241101A: Global MASTER-Net observations report
  8. GRB 241101A: FRAM-ORM optical limit
  9. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  10. EP241021a: Upper limit from Konus-Wind observations
  11. GRB 241101A: Swift-BAT refined analysis
  12. GRB 241030A: further SAO RAS optical observations
  13. GRB 241030A: Optical Observations via Virtual Telescope Project
  14. GRB 241030B: Swift-XRT refined Analysis
  15. GRB 241026A: SAO RAS optical observations
  16. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  17. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  18. GRB 241101A: Swift detection of a burst
  19. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  20. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  21. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  22. GRB 241030B: Montarrenti Observatory optical upper limit
  23. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  24. GRB 241030A: SAO RAS optical observations
  25. GRB 241030A: Fermi GBM Observation
  26. GRB 241030B : GIT optical upper limits
  27. GRB 241030B: LCOGT Optical Upper Limits
  28. GRB 241030B: Swift-BAT refined analysis
  29. GRB 241030A: Swift-BAT refined analysis
  30. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  31. GRB 241030B: Swift/UVOT Detection
  32. GRB 241029A: LCO optical detection
  33. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  34. GRB 241030B: SVOM/GRM observation
  35. GRB 241030B : MITSuME Akeno optical upper limits
  36. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  37. GRB 241030B: SVOM/VT optical afterglow observations
  38. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  39. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  40. GRB241030B: Fermi GBM Observation
  41. GRB 241030B: BTA observations
  42. GRB 241029A: SVOM/VT optical afterglow observations
  43. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  44. GRB 241030B: Enhanced Swift-XRT position
  45. GRB 241030B: optical observations from the INAF Asiago Observatory
  46. GRB241030B: GRANDMA/TAROT Upper Limit
  47. GRB 241030A: Swift-XRT refined Analysis
  48. GRB 241030B: SAO RAS optical observations
  49. GRB 241030B: AKO Optical Afterglow Detection
  50. GRB 241030B: Nanshan/HMT optical afterglow detection
  51. GRB 241030B: SVOM/ECLAIRs detection of a burst
  52. GRB 241030B: Prompt enhanced Swift-XRT position
  53. Konus-Wind detection of GRB 241030A
  54. GRB 241030B: Swift detection of a burst
  55. GRB 241030B: Fermi GBM Final Real-time Localization
  56. GRB 241030A: Fermi-LAT detection
  57. GRB 240912A: radio detection with the VLA
  58. Fermi GRB 241030A: Global MASTER-Net observations report
  59. GRB 241030A: AKO Optical Afterglow Detection
  60. Swift GRB 241030A: Global MASTER-Net observations report
  61. GRB 241030A: Swift/UVOT Detection
  62. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  63. GRB 241030A: SVOM/GRM observation
  64. GRB 241026A: Swift-BAT refined analysis
  65. GRB 241030A: SVOM/C-GFT optical observations
  66. GRB 241026A: LBT optical observations
  67. GRB 241030A: Multiband optical detection with Mephisto
  68. GRB 241030A: SVOM/VT optical afterglow observations
  69. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  70. GRB 241030A : MITSuME Akeno optical afterglow detection
  71. GRB 241030A: Enhanced Swift-XRT position
  72. GRB 241029A: GROWTH-India Telescope optical follow up
  73. GRB 241030A: TRT optical observations
  74. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  75. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  76. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  77. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  78. GRB 241030A: Fermi GBM Final Real-time Localization
  79. GRB 241029A: SAO RAS optical observations
  80. GRB 241026A: SAO RAS optical observations
  81. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  82. EP241021a: SAO RAS observations of rebrightening
  83. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  84. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  85. GRB 241026A: Swift/UVOT Upper Limits
  86. GRB 241029A: Swift-XRT observations
  87. GRB 241029A: Fermi GBM Observation
  88. GRB 241029A: AKO Optical Afterglow Detection
  89. GRB 241029A: GOTO optical afterglow detection
  90. GRB 241029A: MASTER early optical counterpart detection
  91. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  92. GRB 241029A: Mephisto observations
  93. EP 241026b: LBT possible optical counterpart (brightening source)
  94. GRB 241029A: TRT optical afterglow candidate detection
  95. GRB 241029A: Swift ToO observations
  96. GRB 241029A: SVOM/GRM observation
  97. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  98. GRB 241029A: Fermi GBM Final Real-time Localization
  99. GRB 240821A: Keck/LRIS spectroscopic observations
  100. GRB 241026A: the 100th GRB detected by GRBAlpha

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