Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

26483 results found.

  1. GRB 090423: GROND detection and preliminary photo-z
  2. GRB 090423: NOT z-band limit
  3. GRB 090423: Swift-XRT refined analysis
  4. GRB090418A Rc-band photometry
  5. GRB 090423: NIR photometry and evidence for spectral break
  6. GRB 090422: Swift-XRT refined analysis
  7. GRB090423, RIMOTS optical upper limits
  8. GRB 090423: Enhanced Swift-XRT position
  9. GRB 090423: Swift-BAT refined analysis
  10. GRB 090422: Swift/UVOT Upper Limits
  11. GRB 090423: UKIRT K-band observations
  12. GRB 090423: P60 Observations
  13. GRB 090418A: R and I band observation
  14. GRB 090423: Swift detection of a burst
  15. GRB 090422: Liverpool Telescope possible candidate
  16. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  17. GRB 090422: Swift-BAT refined analysis
  18. GRB 090422: Enhanced Swift-XRT position
  19. GRB 090418B: RTT150 optical observations
  20. GRB 080410: GAO 150cm telescope Optical Observation
  21. GRB 080408A: GAO 150cm telescope Optical Observation
  22. GRB 090422: Liverpool Telescope observations
  23. GRB 090418B: Suzaku WAM observation of the prompt emission
  24. GRB 090422: Swift detection of a burst
  25. GRB 090418C: Fermi GBM Detection
  26. GRB 090418A: Swift/UVOT Detection of the Neighbouring Galaxy
  27. GRB 090418B: GRAS002 observatios
  28. GRB 090418B: GROND observations
  29. GRB 090419: Swift/UVOT Observations
  30. GRB 090418B: Faulkes Telescope North observations
  31. GRB 090418A: Swift/UVOT Observations
  32. GRB 090417B: Swift/UVOT Upper Limits
  33. GRB 090417B Correction to the BAT refined analysis position
  34. GRB 090419: Swift-XRT refined analysis
  35. Konus-Wind observation of GRB 090418B
  36. GRB 090419: GROND detection of afterglow candidate
  37. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  38. GRB 090419: Swift-BAT refined analysis
  39. VLA radio detection of GRB 090418
  40. VLA radio upper limit on GRB 090417B
  41. GRB 090419: Enhanced Swift-XRT position
  42. GRB 090418: Swift XRT refined analysis
  43. GRB 090419: Swift detection of a burst
  44. VLA observations of short burst GRB 090417A
  45. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  46. GRB 090417B: Gemini imaging
  47. GRB 090418: Swift-BAT refined analysis
  48. GRB 090417B: Swift-XRT refined analysis
  49. GRB 090418: Enhanced Swift-XRT position
  50. GRB 090418: Swift detection of a burst with optical afterglow
  51. GRB 090411B: Suzaku WAM observation of the prompt emission
  52. GRB 090411A: Suzaku WAM observation of the prompt emission
  53. GRB 090417B: Subaru NIR Observations
  54. GRB 090417B: MITSuME Okayama optical upper limits
  55. GRB 090417B: optical observations
  56. GRB090417B: optical observations
  57. GRB 090417B: Swift-BAT refined analysis
  58. GRB 090417A: Swift-BAT refined analysis
  59. GRB 090417A: Early-type nature of the putative host
  60. GRB 090417A: nearby galaxy redshift
  61. GRB 090417B: Swift detection of a burst
  62. GRB 090412: Fermi GBM detection
  63. GRB 090411B: Fermi GBM detection
  64. GRB 090411A: Fermi GBM detection
  65. GRB 090410: Suzaku WAM observation of the prompt emission
  66. GRB 090410: GROND upper limits
  67. GRB 090410: MITSuME optical upper limits
  68. GRB 090408b: IPN Triangulation
  69. GRB 090328b: IPN Triangulation
  70. GRB 090410: Swift-BAT refined analysis
  71. GRB 090409: Fermi GBM detection
  72. GRB090408, RIMOTS optical upper limits
  73. Swift-BAT trigger 348781: almost certainly not a burst
  74. GRB 090408B: MASTER II-Kourovka optical observations
  75. GRB 090407: GROND upper limits
  76. GRB 090407: VLT observations
  77. GRB 090407: Swift-XRT refined analysis
  78. GRB 090407: Swift UVOT Upper Limits
  79. GRB 090407: Enhanced Swift-XRT position
  80. GRB 090407: Swift-BAT refined analysis
  81. GRB 090407: ROTSE-III Optical Limits
  82. GRB 090407: Swift detection of a burst
  83. GRB 090404: millimeter detection
  84. GRB 090405: Fermi GBM Detection
  85. GRB 090403: Fermi GBM detection
  86. GRB 090404: GROND upper limits
  87. GRB 090404: further NOT observations
  88. Swift/UVOT observations of GRB090404
  89. GRB 090404: NOT observations
  90. GRB 090404: Swift-XRT Team refined analysis
  91. GRB 090404: Swift-BAT refined analysis
  92. GRB 090404: Enhanced Swift-XRT position
  93. GRB 090404: Swift detection of a burst
  94. GRB 090401A: Suzaku WAM observation of the prompt emission
  95. GRB 090401B: Suzaku WAM observation of the prompt emission
  96. GRB 090401B: Xinglong TNT optical Upper Limit
  97. GRB 090401B: VLA radio upper limit
  98. GRB 090401B: Upper limits of MITSuME optical observation
  99. GRB090401B, RIMOTS optical upper limits
  100. GRB 090401B: AGILE refined analysis

Advanced

Download all Circulars as a .tar.gz archive:
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