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"

27408 results found.

  1. GRB 090709: Swift detection of a bright burst
  2. GRB 090708: Early RAPTOR Optical Limits
  3. GRB 090708, Swift-BAT refined analysis
  4. GRB 090708: ROTSE-III Optical Limits
  5. GRB 090708: Swift detection of a burst
  6. GRB 090704: a long GRB found in INTEGRAL off-line analysis
  7. GRB 090706: Fermi GBM detection
  8. Swift-BAT trigger 356516 is not a GRB
  9. Possible GRB090705: Swift-XRT observations
  10. GRB 090705: PAIRITEL NIR Observations
  11. GRB 090705: Swift detection of a possible burst
  12. GRB 090703: Fermi GBM detection
  13. GRB 090702: UVOT upper limits
  14. XRF 090702: Swift-XRT afterglow position
  15. GRB 090701: Fermi GBM detection
  16. GRB 090628: Swift XRT refined analysis
  17. GRB 090630: Fermi GBM detection
  18. GRB 090628: Swift/UVOT Upper Limits
  19. Konus-Wind observation of GRB 090626
  20. GRB080628: SAO RAS optical observations
  21. GRB 090628: Swift-BAT refined analysis
  22. GRB 090628: GROND upper limits
  23. GRB 090626: IPN localization
  24. GRB 090628: Swift/UVOT Finding Chart Observation
  25. GRB 090628: Swift XRT position
  26. GRB 090628: Swift detection of a burst
  27. Fermi LAT observations of GRB 090626
  28. GRB 090625B: Fermi GBM observation
  29. GRB 090625B: Swift-XRT refined analysis
  30. GRB 090626: Fermi GBM detection
  31. GRB 090623: Suzaku WAM observation of the prompt emission
  32. GRB 090618: SARA Second Epoch Observations
  33. GRB 090625B: Faulkes Telescope South observations
  34. GRB 090625: Fermi GBM detection
  35. GRB 090617: Suzaku WAM observation of the prompt emission
  36. GRB 090623: Fermi GBM detection
  37. GRB 090621B: GRT Optical Observation
  38. GRB 090621A: GRT Optical Observation
  39. PAIRITEL observations of GRB 090618
  40. GRB 090621B: Fermi GBM detection
  41. GRB 090621D: Fermi GBM detection
  42. GRB 090621C: Fermi GBM detection
  43. GRB 090621: Fermi GBM observation
  44. GRB 090620: Fermi GBM detecion
  45. GRB 090621B: Swift/UVOT Upper Limits
  46. GRB 090621B: Swift-BAT refined analysis
  47. GRB 090621B: Swift-XRT refined analysis
  48. GRB 090621B: RTT150 optical observations
  49. GRB 090621A: Swift-BAT refined analysis
  50. GRB 090621B: Swift detection of a short hard burst
  51. GRB 090621: Swift/UVOT Upper Limits
  52. GRB 090621: Swift-XRT Team refined analysis
  53. GRB 090618: BOAO V-band Observation
  54. GRB 090621: Swift detection of a burst
  55. GRB 090618: Fermi GBM observation
  56. GRB 090618, Swift-BAT refined spectral analysis
  57. GRB090618 - Continued optical monitoring and light curve break
  58. GRB 090618: Swift-BAT refined analysis
  59. GRB 090618: SARA observations
  60. GRB090618: Swift-XRT team refined analysis
  61. GRB090618: Swift/UVOT bright afterglow detection
  62. Swift XRT observations of GRB 090531A
  63. GRB 090618: AGILE observations
  64. GRB 090617: Fermi GBM detection
  65. GRB 090618: LOAO R-band Observation
  66. GRB 090618 Faulkes Telescope North observations
  67. Optical observations of GRB 090618
  68. GRB 090618: OA behavior from KAIT
  69. GRB 090618: ROTSE-III Detection of Optical Counterpart
  70. GRB090618: P60 Optical Afterglow
  71. GRB 090618: Swift detection of a bright burst with optical afterglow
  72. GRB 090616: Fermi GBM detection
  73. GRB 090612: Fermi GBM detection
  74. GRB 090610C: Fermi GBM detection
  75. GRB 090610B: Fermi GBM detection
  76. GRB 090610: Fermi GBM detection
  77. SGR 0418+5729 Fermi/GBM Detection of Pulsations
  78. GRB 090602: Suzaku WAM observation of the prompt emission
  79. GRB 090531B: Fermi GBM detection
  80. Discovery of a new soft gamma repeater source, SGR 0418+5729
  81. GRB 090608: Fermi GBM detection
  82. GRB 090606: Fermi GBM detection
  83. GRB 090607: XRT Team Refined Analysis
  84. GRB 090607: Swift/UVOT Upper Limits
  85. GRB 090607: Swift-BAT refined analysis of the SHB
  86. GRB 090607: Faulkes Telescope North observations
  87. GRB 090607: Swift detection of a burst
  88. Ignore GCN/Swift-BAT Lightcurve Notices for trigger 353567
  89. GRB 090530B: Suzaku WAM observation of the prompt emission
  90. GRB 090530: RTT150 Optical Observation
  91. GRB 090602: Fermi GBM detection
  92. GRB 090529A: RTT150 Optical Observations
  93. GRB 090528: Suzaku WAM observation of the prompt emission
  94. GRB 090531B: GROND observation
  95. GRB 090528B: Suzaku WAM observation of the prompt emission
  96. GRB 090530: Early RAPTOR Optical Observations
  97. GRB090529B: ROVOR Upper Limits
  98. GRB 090531B: Swift/BAT spectral lag results
  99. GRB 090529C: Fermi GBM detection
  100. GRB 090529B: Fermi GBM detection

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