Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

22062 results found.

  1. GRB010214, candidate optical afterglow
  2. GRB010214, optical observations
  3. GRB 010214, Optical Observations
  4. GRB010213, Radio Observations
  5. GRB010213 Optical Observation
  6. GRB010213, Radio Observations
  7. J-Band Observation of GRB 010214.
  8. GRB010214, Radio Observations
  9. GRB010214, optical observations
  10. GRB010213, optical observations
  11. GRB010213, Near-IR observations
  12. Possible InfraRed Transient of GRB 010214.
  13. GRB010214 Optical Observation
  14. GRB010214: BeppoSAX/NFI Observations
  15. GRB010213 (HETE) TAROT observations
  16. GRB 010214, optical observations
  17. GRB010213 detected by HETE
  18. IPN Status Report
  19. IPN/RXTE TRIANGULATION OF GRB010126
  20. GRB010126, TNG R-band observations
  21. GRB010126 Optical Observations
  22. GRB010126 optical observations
  23. GRB010126: Optical observations
  24. IPN TRIANGULATION OF GRB010126
  25. IPN/RXTE TRIANGULATION OF GRB010126
  26. GRB 010119, optical observations
  27. GRB010119: Optical observations
  28. Optical Observations of GRB 001018 at Keck
  29. GRB010119, Radio observations
  30. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  31. Optical observations of GRB 001018 with JCAM
  32. IPN TRIANGULATION OF GRB010115
  33. IPN TRIANGULATION OF GRB010109
  34. GRB010103, optical observations
  35. IPN triangulation of GRB010104
  36. IPN triangulation of GRB010103
  37. GRB 001204: Ks observations
  38. H band observation of GRB 001212
  39. IPN triangulation of GRB001219
  40. GRB 001212 possible OA in 2MASS
  41. GRB 001212 possible OA
  42. IPN triangulation of GRB001212
  43. GRB001204: Optical observations
  44. Confirmation of IPN position for GRB001204
  45. GRB001204, Radio observations
  46. IPN triangulation of GRB001204 (short/hard)
  47. GRB 001105, further optical observations
  48. GRB001120: Gunn-i observations
  49. GRB001120: Optical observations
  50. GRB001109, optical observations
  51. GRB001120, optical observations
  52. WSRT 4.8 GHz observations of GRB001109
  53. IPN triangulation of GRB001120
  54. Optical/NIR observations of GRB001109
  55. GRB 001109: deep JHK upper limits
  56. GRB001109: Optical observations
  57. GRB001109: BeppoSAX/NFI Observations
  58. GRB001109, R-band optical observations
  59. GRB001109, Radio observations
  60. IPN TRIANGULATION OF GRB001105
  61. GRB000926: R-image of the host galaxy
  62. GRB 001025B, I-band observations
  63. GRB001025B, Radio observations
  64. GRB 001025 Optical Observations
  65. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  66. IPN triangulation of GRB001025
  67. GRB001007: Optical observations
  68. ASM Localization of GRB 001025
  69. GRB001007, Radio observations
  70. IPN TRIANGULATION OF GRB001020
  71. GRB001019, Optical Observations
  72. GRB 001018, Possible Radio Afterglow
  73. GRB001018, Gamma Ray Observations
  74. IPN TRIANGULATION OF GRB001019
  75. IPN TRIANGULATION OF GRB001018
  76. IPN TRIANGULATION OF GRB 001017
  77. V,R,I band observations of GRB000926
  78. The Likely Optical/Infrared Afterglow of GRB 001011
  79. GRB 001007, BVR-band observations
  80. GRB000926 - Amateur Optical Observations
  81. GRB001007: Optical observations
  82. IPN triangulation of GRB001007
  83. IPN triangulation of GRB001005
  84. IPN triangulation of GRB 001004
  85. GRB000926 - Optical observations
  86. GRB000926 - Optical observations
  87. GRB000911: VLT infrared observation
  88. GRB000926 - Optical observations
  89. GRB000926 - Optical observations
  90. GRB 000926: optical observations
  91. GRB 000926, Optical Observations
  92. GRB000926 - Optical observations
  93. GRB000911: optical VLT observations
  94. GRB000926 K'-band Observation
  95. GRB000926 optical observations
  96. GRB000926 - Optical observations
  97. J and K band observations of GRB 000926
  98. GRB000911 Optical Observations
  99. GRB 000926, optical observation by Oksanen (vsnet-grb)
  100. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.

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