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"

12334 results found.

  1. Konus-Wind observation of GRB 150530A
  2. GRB 150530B: Swift-XRT observations
  3. GRB 150530A: RATIR Optical Observations
  4. GRB 150530A: Swift/UVOT Upper Limits
  5. GRB 150530A: Swift detection of a burst
  6. GRB 150513A: Swift-XRT observations
  7. GRB 150527A: MITSuME Okayama upper limits
  8. GRB 150527A: Swift/UVOT Upper Limits
  9. GRB 150527A: RATIR Afterglow Detection
  10. GRB 150527A: Swift detection of a burst
  11. GRB 150513A: request for X-ray follow up
  12. Swift trigger 641332 is probably not an astrophysical source
  13. GRB 150518A: Continued RATIR optical observations
  14. GRB 150518A: MAXI-GSC further analysis
  15. GRB 150518A: AMI 15 GHz detection of possible radio counterpart
  16. GRB 150518A : Xinglong TNT upper limit
  17. GRB 150518A: RATIR optical observations
  18. Swift/UVOT observations of GRB150518A
  19. Konus-Wind observation of GRB 150514A
  20. Konus-Wind observation of GRB 150510A
  21. GRB 150423A: Chandra X-ray Observation
  22. Confirmation that Swift Trigger 639636 is not astrophysical
  23. Swift Trigger 639636: a possible GRB
  24. GRB 150413A: AMI 15 GHz confirmation of radio counterpart
  25. GRB 150430A: GROND Upper Limits
  26. GRB 150430A: MAXI/GSC detection
  27. GRB 150430A: Swift/UVOT Upper Limits
  28. GRB 150428B: IRSF NIR upper limits
  29. GRB 150428B: Swift/UVOT Upper Limits
  30. GRB 150428C: Swift-XRT observations
  31. GRB 150428A: Swift/UVOT Upper Limits
  32. GRB 150428B: MASTER-net prompt optical observation
  33. GRB 150428A: MASTER-net early optical observation
  34. GRB 150428C/MAXI J0400+678: MAXI/GSC detection
  35. GRB 150428A: RATIR optical observations
  36. GRB 150428B: Swift detection of a burst
  37. GRB 150424A: RATIR Observations
  38. GRB 150424A: 10.4m GTC spectroscopy
  39. GRB 150423A: VLT/X-shooter spectroscopy and tentative redshift
  40. GRB 150423A: Continued RATIR optical afterglow monitoring
  41. Konus-Wind observation of GRB 150424A
  42. GRB 150424A: Swift/UVOT Observations
  43. GRB 150424B: MAXI/GSC detection
  44. GRB 150424A: Swift detection of a short burst
  45. GRB 150423A: MITSuME Okayama upper limits
  46. GRB 150423A: Swift/UVOT Upper Limits
  47. GRB 150423A: RATIR optical afterglow monitoring
  48. GRB 150423A: KAIT Optical Upper Limit
  49. GRB 150423A: Swift detection of a short burst
  50. Further Swift XRT observations of GRB 150418A
  51. Swift trigger 638589 is probably not an astrophysical source
  52. GRB 150413A: Swift-XRT observations
  53. GRB 150418A: Swift-XRT observations
  54. GRB 150418A: MAXI/GSC detection
  55. Confirmation that Swift trigger 638217 is not an astrophysical source
  56. Swift Trigger 638217 is probably not an astrophysical source
  57. GRB 150413A: AMI 15 GHz detection of possible radio counterpart
  58. GRB 150413A: optical observations
  59. GRB 150413A: MAXI/GSC detection
  60. Swift GRB150402A: further XRT observations
  61. GRB 150407A: Swift-XRT observations
  62. Swift triggered on a source in Terzan 5 (trigger=637212)
  63. Fermi trigger 449861706: MASTER-SAAO possible candidate to OT of Short GRB
  64. GRB 150403A: Swift/UVOT Detection
  65. GRB 150323C: CrAO optical observations
  66. GRB 150402A: results of Swift observations
  67. GRB 150402A: RATIR Optical Observations
  68. GRB 150323A: AAO optical observations
  69. Konus-Wind observation of GRB 150323B
  70. Konus-Wind observation of GRB 150323A
  71. GRB 150323B : Xinglong TNT upper limit
  72. GRB 150323C: Swift/UVOT Upper Limits
  73. GRB 150323B: Swift-XRT observations
  74. GRB 150323C: RATIR Optical Afterglow Observations
  75. GRB 150323C: Xingming upper limit
  76. GRB 150323C: MASTER-net optical observation
  77. GRB 150323C: Swift detection of a burst
  78. GRB150323A: Swift-UVOT detection of the afterglow
  79. GRB 150323A: RATIR Optical Afterglow Observations
  80. GRB 150323A: Swift detection of a burst
  81. Confirmation that Swift trigger 635306 is not an astrophysical source
  82. GRB 150318A: Swift/UVOT Upper Limits
  83. GRB 150318A : GROND upper limits
  84. GRB 150318A: Swift detection of a burst
  85. GRB 150317A: Swift/UVOT Upper Limits
  86. GRB 150317A: RATIR Optical Afterglow Detection
  87. GRB 150317A: Swift detection of a burst
  88. GRB 150314A: Swift/UVOT Detection
  89. GRB 150314A: MITSuME Akeno upper limits
  90. GRB 150313A: MAXI/GSC detection
  91. GRB 150309A: AAO optic upper limit
  92. GRB 150311A: MAXI/GSC possible afterglow detection
  93. GRB 150309A: CrAO optic upper limit
  94. GRB 150309A: ISON-Kislovodsk optic upper limit
  95. GRB 150309A: Swift/UVOT Upper Limits
  96. GRB 150309A: MASTER prompt optical observation
  97. GRB 150309A: BOOTES-1 and -2 upper limit
  98. GRB 150309A: Swift detection of a burst
  99. Swift J0045.2+4151: analysis of XMM-Newton archival data
  100. Further UVOT Observations of Swift J0045.2+4151

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov