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"

32688 results found.

  1. Swift/UVOT refined analysis of GRB070531
  2. GRB 070531: Swift-BAT refined analysis
  3. GRB 070531: Swift-XRT position
  4. GRB 070531: Liverpool Telescope Optical Observations
  5. GRB 070529: SARA upper limit
  6. Swift/UVOT refined analysis of GRB070529
  7. GRB 070529: MARGE Observations
  8. GRB 070529: Optical aterglow from MIRO
  9. GRB 070529: Gemini Redshift
  10. GRB 070529: Swift-XRT refined analysis
  11. GRB 070529, Swift-BAT refined analysis
  12. GRB 070529: Xinglong TNT Optical Upper Limit
  13. GRB 070412: Deep Keck imaging
  14. Swift Triggers 280447, 280450 and 280451 are invalid
  15. GRB 070518, deep LBT photometry
  16. GRB 070518: MARGE Observations
  17. Konus-Wind observation of GRB 070521
  18. GRB 070518: optical observation
  19. GRB070521: Second Epoch Gemini Imaging
  20. GRB070521: NIR observations
  21. GRB070520B: NIR observations
  22. GRB 070521: Swift/UVOT Upper Limits
  23. GRB 070521, optical observation
  24. GRB 070521: Swift-XRT refined analysis
  25. GRB 070521: Keck imaging
  26. GRB070521: Gemini Observations
  27. GROND upper limits of GRB 070521
  28. GRB 070521 Milagro GeV/TeV Observations
  29. GRB 070520B: SARA upper limit
  30. GRB 070520A: SARA upper limit
  31. GRB 070521: SARA upper limit
  32. GRB 070521: Subaru observations and possible host detection
  33. GRB070518: Optical/NIR observation
  34. GRB 070520B: Swift/UVOT Upper Limits
  35. GRB 070520A: Subaru Observations
  36. GRB 070521, Swift-BAT refined analysis
  37. GRB 070520A: Swift UVOT Upper Limits
  38. GRB 070520B: Swift-XRT refined analysis
  39. GRB070521: P200 Observations
  40. GRB070521 : Faulkes Telescope North Observations
  41. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  42. GRB 070520A: MITSuME Akeno optical upper limits
  43. GRB 070520B, Swift-BAT refined analysis
  44. GRB 070520A, Swift-BAT refined analysis
  45. GRB 070520A: Swift-XRT refined analysis
  46. GRB 070518: TNG observations
  47. GRB 070520: Xinglong EST optical Upper Limit
  48. VLA observation of GRB 070518
  49. GRB 070518: Swift-XRT refined analysis
  50. GRB 070517: Gemini optical imaging
  51. GRB070518: UVOT refined analysis
  52. GRB 070518, Swift-BAT refined analysis
  53. GRB 070518: OT confirmed form Xinglong TNT observation
  54. GRB070517: Swift-XRT Refined Analysis
  55. GRB 070517, Swift-BAT refined analysis
  56. GRB 070509: objects inside XRT error circle
  57. GRB070419A: optical observations
  58. GRB 070419A, Deep LBT photometry
  59. GRB 070509: Swift/UVOT Upper Limits
  60. Konus-Wind and Konus-A observation of GRB 070508
  61. Swift-BAT trigger 278987 is not a GRB
  62. GRB070509: Swift-XRT Refined Analysis
  63. RHESSI Spectrum of GRB070508
  64. GRB 070508: OA fading and tentative redshift
  65. GRB 070509, Swift-BAT refined analysis
  66. GRB 070508: Suzaku/WAM observation of the prompt emission
  67. GRB 070509: REM observations
  68. GRB 070509: ROTSE-III Optical Limits
  69. GRB070508: Swift/UVOT Observations
  70. GRB 070508, SMARTS optical afterglow observation
  71. GRB 070508, Swift-BAT refined analysis
  72. GRB 070508: Multicolor optical observations and possible redshift limit
  73. GRB 070508: Swift-XRT refined analysis
  74. GRB 070508: Optical observation limiting magnitude
  75. GRB 070508: Optical afterglow detection
  76. GRB 070508: REM observations
  77. GRB070412: MAGIC telescope GeV observation
  78. Swift-BAT trigger 278809 is not a GRB
  79. GRB 070506: VLT redshift
  80. GRB070506: Swift/UVOT Observations
  81. GRB070506: Swift XRT refined analysis
  82. GRB 070506, Swift-BAT Refined Analysis
  83. GRB 070412, deep LBT imaging
  84. GRB 070429A: Swift XRT further analysis
  85. GRB070429B: VLT observations
  86. GRB 070429A: optical observations
  87. GRB070429B: position correction
  88. GRB 070309: Swift-XRT afterglow confirmation
  89. GRB070429B: possible host galaxy detection
  90. VLA observation of GRB 070429B
  91. Swift/UVOT observations of GRB070429B
  92. GRB 070429B, Swift-BAT refined analysis
  93. Swift/UVOT observations of GRB070429A
  94. GRB 070429A: Swift XRT refined analysis
  95. GRB 070429A, Swift-BAT refined analysis
  96. GRB 070429B: Swift XRT refined analysis
  97. GRB 070429B: ROTSE-III Optical Limits
  98. GRB 070429: ROTSE-III Optical Limits
  99. GRB 070427, Swift-BAT Refined Analysis
  100. LT monitoring of GRB070412

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