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"

32714 results found.

  1. EP 260225.148: COLIBRÍ Confirmation of flaring star
  2. EP260223a: Xinglong optical upper limit
  3. GRB 260223A: Glowbug gamma-ray detection
  4. EP260213a: Mephisto optical upper limits
  5. EP260223a: EP-FXT follow-up observation
  6. sb26021801: SVOM/VT optical upper limits
  7. GRB 260223A: COLIBRÍ optical afterglow decay confirmation
  8. sb26021801: SVOM/C-GFT upper limit
  9. EP260223a: COLIBRÍ optical upper limits
  10. GRB 260223A: SVOM/VT optical observation
  11. GRB 260223A: SVOM/GRM observation
  12. GRB 260223A: COLIBRÍ further optical observations and a brightening
  13. EP260221a: Optical upper limit with Kinder observations
  14. GRB 260223A: COLIBRÍ optical observations
  15. GRB 260223A: DDOTI Optical Candidate
  16. Fermi GRB 260223A: Global MASTER-Net observations report
  17. EP260221a: Liverpool Telescope detection of COLIBRÍ counterpart candidate
  18. EP260221a: COLIBRÍ optical counterpart candidate
  19. EP260221a: Gemini South z-band upper limit
  20. EP260221a: Global MASTER-Net observations report
  21. EP260221a: EP-FXT follow-up observation
  22. Fermi GRB 260221B: Global MASTER-Net observations report
  23. EP260221a: Xinglong optical upper limit
  24. Fermi GRB 260221A: Global MASTER-Net observations report
  25. EP260221a: GOTO optical upper limit
  26. EP260221a: COLIBRÍ optical upper limit
  27. SVOM alert sb26021801: LCO optical upper limit
  28. GRB 260219A: AstroSat CZTI detection
  29. IceCube-260217A: Upper limits from a search for additional neutrino events in IceCube
  30. GRB 260219A: GECAM-B observation of a long burst
  31. Fermi GRB 260219A: Global MASTER-Net observations report
  32. SVOM alert sb26021801: LAST optical upper limit
  33. sb26021801: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  34. Fermi-LAT Gamma-ray Observations of IceCube-260217A
  35. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  36. EP260214b: Mondy optical observations
  37. EP260214b: 1.3m DFOT optical upper limit
  38. EP260210a: Mondy optical upper limits
  39. Konus-Wind detection of GRB 260212A
  40. GRB 260208A: AbAO and Terskol optical upper limits
  41. GRB 260208A: continued Mondy optical observations
  42. IPN triangulation of GRB 260212A
  43. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  44. GRB 260213A: GECAM-B observation of a short burst
  45. EP260214b: Liverpool Telescope optical observations
  46. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  47. EP260214b: Optical upper limit with Kinder observations
  48. EP260214a: Optical upper limits with Kinder observations
  49. EP260214b: EP-FXT follow-up observation
  50. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  51. EP260214b: DDOTI Optical Detection
  52. EP260214b: GROWTH-India Telescope optical upper limit
  53. EP260214a: VLT near-infrared observation
  54. EP260214b: SVOM/VT optical observation
  55. EP260214a: NOT optical upper limits
  56. EP260214a: COLIBRÍ optical upper limits
  57. EP260214b: OHP/T120 optical observations
  58. EP260214a: refined analysis of the EP-FXT observation
  59. EP260214b: LCO optical counterpart detection
  60. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  61. GRB 260211A: SVOM/VT optical counterpart
  62. EP260214b: COLIBRÍ optical observations
  63. EP260214a: SVOM/VT optical upper limits
  64. EP260214b: NOT optical counterpart detection
  65. EP260214a: Global MASTER-Net observations report
  66. GRB 260212A: AstroSat CZTI detection
  67. GRB 260212A: Fermi GBM Observation
  68. EP260213a: Liverpool Telescope optical upper limits
  69. EP260213a: Global MASTER-Net observations report
  70. EP260213a: COLIBRÍ optical upper limits
  71. GRB 260212A: GECAM-B observation
  72. EP260213a: Optical upper limits with Kinder observations
  73. EP260213a: SVOM/VT optical upper limit
  74. EP260213a: Mondy R-band optical upper limit
  75. EP260213a: NUTTelA-TAO Early Optical Limits
  76. EP260213a: SVOM/C-GFT upper limit
  77. EP260213a: refined analysis of the EP-FXT observation
  78. GRB 260212A: SVOM/GRM observation of a long burst
  79. GRB 260211A - SVOM/ECLAIRs refined analysis
  80. GRB 260204A: SVOM/ECLAIRs refined analysis
  81. GRB 260211A: EP-FXT follow-up observation
  82. GRB 260211A: SVOM/VT optical observation
  83. GRB 260212A: Glowbug gamma-ray detection
  84. GRB 260211A: GOTO optical upper limit
  85. Fermi GRB 260212A: Global MASTER-Net observations report
  86. GRB 260211A: LAST optical upper limit
  87. GRB 260210A: SVOM/GRM observation
  88. Fermi GBM Sub-Threshold Detection of GRB 260211A
  89. Konus-Wind detection of GRB 260207B
  90. GRB 260128B: SVOM/ECLAIRs refined analysis
  91. GRID detection of GRB 260207B
  92. GRB 260211A: LCO optical upper limits
  93. GRB260131A/B: 3.6m DOT Optical Observations
  94. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  95. GRB 260208A: Swift UVOT detection
  96. Konus-Wind detection of GRB 260127B
  97. EP260209a: COLIBRÍ optical upper limit
  98. Fermi GRB 260210C: Global MASTER-Net observations report
  99. EP260209a: LCO optical upper limits
  100. EP260210a: 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