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"

43601 results found.

  1. GRB 150126A: MAXI/GSC afterglow candidate detection
  2. Konus-Wind observation of GRB 150123A
  3. GRB 150120A: possible AMI 15 GHz detection
  4. GRB 150123A: Swift/UVOT observations
  5. GRB 150123A: Swift-XRT observations
  6. GRB 150120B: Mondy optical observations
  7. GRB 150123A Tiled Swift observations
  8. GRB 150123A: MAXI/GSC detection
  9. Konus-Wind observation of GRB 150118B
  10. GRB 150120B: RATIR Optical and NIR Observations
  11. IPN Triangulation of GRB 150118B (long/intense)
  12. GRB 150120A: ISON-NM early optical limit
  13. GRB 150120B: FTN early optical light curve
  14. GRB150120B: Xinglong TNT optical observation
  15. GRB 150120B: GROND Afterglow Detection
  16. GRB 150120B: Additional P60 observations
  17. GRB 150120A: Swift-XRT refined Analysis
  18. GRB 150101B: Confirmation of a fading optical counterpart
  19. GRB 150120B: Swift-BAT refined analysis
  20. GRB 150120A: Swift-BAT refined analysis
  21. GRB 150118C: Fermi GBM Detection
  22. Konus-Wind observation of GRB 150118C
  23. GRB 150101B/Swift J123205.1-105602: TNG NIR follow-up
  24. GRB 150120B: Swift-XRT refined Analysis
  25. IPN triangulation of GRB 150118C (short/hard)
  26. GRB 150110B: AMI 15 GHz detection of possible radio counterpart
  27. GRB 150101B/Swift J123205.1-105602, deep VLT observations
  28. GRB 150120B: Enhanced Swift-XRT position
  29. GRB 150120A: Fermi GBM observation
  30. GRB 150101B/Swift J123205.1-105602: XMM-Newton observation
  31. GRB 150120A: Enhanced Swift-XRT position
  32. GRB 150120B: FTN optical afterglow confirmation
  33. GRB 150120B: P60 optical afterglow
  34. GRB 150120B: Swift detection of a burst
  35. GRB 150120A: Gemini-North optical imaging
  36. GRB 150120A: P60 optical observations
  37. GRB 150120A: Prompt enhanced Swift-XRT position
  38. GRB 150120A: Swift detection of a possibly-short burst
  39. GRB 150101B/Swift J123205.1-105602: continued WSRT radio and VLT optical observations
  40. GRB 150118B: Fermi GBM Detection
  41. GRB 150118B: Fermi-LAT detection
  42. Trigger 626581: Swift detection of GRO J1008-57
  43. GRB 150110B: Khureltogot optical upper limit
  44. The Swift Detection of a Large Flare from the RS CVn Binary SZ Psc
  45. Swift detection of the variable star SZ Psc
  46. GRB 150110C: Swift-XRT observations
  47. GRB 150110B: Swift-BAT refined analysis
  48. GRB 150110A: MASTER inspection
  49. GRB 150110C Tiled Swift observations
  50. GRB 150110B: Swift-XRT refined Analysis
  51. GRB 150110B: Swift/UVOT Upper Limits
  52. GRB 150110B: Fermi GBM Detection
  53. GRB 150110B: Enhanced Swift-XRT position
  54. GRB 150110C: MAXI/GSC detection
  55. GRB 150110A: Fermi GBM Detection
  56. GRB 150110B: Swift detection of a burst
  57. GRB 150110A: MAXI/GSC detection
  58. GRB 150101B/Swift J123205.1-105602: Chandra observations
  59. GRB 150101B / Swift J123205.1-105602: 9.8 GHz VLA observations
  60. Fermi GBM trigger 150108121 is not a GRB
  61. GRB 150101B/Swift J123205.1-105602: WSRT radio observation
  62. GRB 150101B / Swift J123205.1-105602: X-ray counterpart is likely an AGN
  63. Radio upper limit on the GRB 141121A with the GMRT
  64. Fermi GBM trigger 150106207 is not a GRB
  65. GRB 150105A: Fermi GBM detection
  66. GRB 150101B/Swift J123205.1-105602: VLT observations and redshift
  67. Swift detection of 4U 1700+24 (= V* V934 Her)
  68. GRB 150103A: MASTER optical observations
  69. GRB 150101B: potential host galaxy redshift by GTC
  70. GRB 150103A: Swift-XRT refined Analysis
  71. GRB 150101B: Fermi GBM detection
  72. GRB 150103A: Swift-BAT refined analysis
  73. GRB 150103A: Zadko observatory - Gingin optical observations
  74. GRB 150103A: Enhanced Swift-XRT position
  75. Swift J123205.1-105602: Magellan candidate afterglow
  76. GRB 150103A: Prompt enhanced Swift-XRT position
  77. GRB 150103A: Swift detection of a burst
  78. Swift J123205.1-105602: XRT and UVOT observations of soft short burst source
  79. Short burst found in ground analysis of Swift-BAT data
  80. GRB 150101A Swift-BAT refined analysis of the short hard burst
  81. GRB 150101A: Fermi GBM detection
  82. GRB 150101A: Swift-XRT refined Analysis
  83. GRB 150101A: Swift/UVOT Upper Limits
  84. GRB 150101A: Enhanced Swift-XRT position
  85. GRB 150101A: Swift detection of a short burst
  86. Konus-Wind observation of GRB 141229A
  87. GRB 141229A: Deep MASTER inspection
  88. Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
  89. GRB 141230A: Fermi GBM detection
  90. GRB 141229A Swift-BAT observations
  91. GRB 141230A: Nanshan optical obsrvations
  92. GRB 141230A: iPTF Optical Observations and Candidate Afterglow iPTF14jko
  93. GRB 141229A: 1.23m CAHA optical observations
  94. GRB 141229A: Nanshan optical upper limit
  95. GRB 141229A: Swift-XRT observations
  96. Fermi GBM trigger 141229739 is not a GRB
  97. GRB 141229A: Fermi GBM detection
  98. Christmas GRB 141225A: GROND Observations
  99. GRB 141229A Tiled Swift observations
  100. GRB 141229A: MAXI/GSC detection

Advanced

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