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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"

19725 results found.

  1. GRB 130427A: CARMA 85 GHz detection
  2. GRB 130427B: Swift-XRT refined Analysis
  3. GRB 130427A: NOT optical photometry and redshift
  4. GRB 130427B: MITSuME Okayama upper limits
  5. GRB 130427A: T100 observations
  6. GRB 130427A: optical observations in CrAO
  7. GRB 130427A: Fermi GBM observation
  8. GRB 130427A: Fermi-LAT detection of a burst
  9. GRB 130427A: Zadko observatory - Gingin optical observations
  10. GRB 130427B: Enhanced Swift-XRT position
  11. GRB 130427A: GMG optical observation
  12. GRB 130427A: MITSuME Okayama Optical Observation
  13. GRB 130427B: Swift detection of a burst with optical counterpart
  14. GRB 130427A: RATIR Optical and NIR Observations
  15. GRB 130427A: Weihai optical observations
  16. GRB 130427A: Continued P60 follow-up of an extremely bright optical afterglow
  17. GRB 130427A: PAIRITEL NIR Detections
  18. GRB 130427A: early optical observations
  19. GRB 130427A: Swift detection of a very bright burst with a likely bright optical counterpart
  20. GRB 130420A: Continued Skynet/GORT Observations/Detections
  21. Trigger 554491: Swift detection of a spike possibly from Sgr A*
  22. GRB 130420A: Continued RATIR Optical and NIR Observations
  23. GRB 130420A: Continued RATIR Optical and NIR Observations
  24. GRB 130418A: Continued RATIR Optical and NIR Observations
  25. Swift Trigger 554135 is probably not a GRB or transient
  26. GRB 130420B: RATIR Optical and NIR Observations
  27. GRB 130420A: Continued RATIR Optical and NIR Observations
  28. GRB 130420B: Swift-XRT refined Analysis
  29. GRB 130420A: ISON-NM optical observations
  30. Skynet/GORT observations of GRB130420A
  31. GRB 130420B: Weihai optical upper limit
  32. GRB 130420B: Swift/UVOT Upper Limits
  33. GRB 130420A: Swift/UVOT Detection
  34. GRB130420B: GMG optical upper limit
  35. GRB 130420B: Enhanced Swift-XRT position
  36. GRB 130420A: GMG optical observation
  37. GRB 130420A: Enhanced Swift-XRT position
  38. GRB130420A : Xinglong TNT optical upper limit
  39. GRB 130420A: Weihai Optical Observations
  40. GRB 130420B: Swift detection of a burst
  41. GRB 130420A: RATIR Optical and NIR Observations
  42. GRB 130420A: PAIRITEL NIR detections
  43. GRB 130420A: Swift detection of a burst with an optical counterpart
  44. GRB 130418A: Continued RATIR Optical and NIR Observations
  45. GRB 130418A: SMARTS optical/IR afterglow observations
  46. GRB 130418A: Submm observations from SMA
  47. GRB 130419A, Swift-BAT refined analysis
  48. GRB 130327B: Swift/XRT source is not the afterglow
  49. Trigger 553930: Swift detection of a possible flare from HR 5110
  50. GRB 130418A: LOAO Observation
  51. GRB 130418A, Swift-BAT refined analysis
  52. GRB 130418A: REM NIR observations
  53. GRB 130418A: RATIR Optical and NIR Observations
  54. GRB 130418A: GROND detection of the optical-NIR afterglow
  55. GRB130418A: OSN 1.5m fading afterglow detection
  56. GRB 130418A: Swift/UVOT Detection and request for continuing coverage
  57. GRB 130418A: Enhanced Swift-XRT position
  58. GRB 130418A: TAROT Calern and TAROT la Silla observatory optical observations
  59. GRB 130418A: TNG optical observations
  60. GRB 130418A: Bassano Bresciano Observatory optical observations
  61. GRB 130418A: 1.23m I-band observations
  62. GRB 130418A: Swift detection of a burst with an optical counterpart
  63. GRB 130408a: Skynet Optical Observations
  64. GRB 130408A: SMARTS optical/IR afterglow observations
  65. GRB 130408A: Zadko observatory - Gingin optical observations
  66. GRB130408A: Swift/UVOT followup observations
  67. GRB 130408A: Enhanced Swift-XRT position
  68. GRB 130408A: GROND detection of the afterglow
  69. GRB 130408A: Swift detection of a burst
  70. GRB 130407A: MAXI/GSC detection
  71. GRB 130211A: Retraction of afterglow candidate
  72. Swift detection of IGR J18245-2452
  73. IPN Triangulation of GRB 130320B (very long/bright)
  74. GRB 130327A: RATIR Optical/NIR afterglow confirmation
  75. GRB 130310A: RATIR Observations
  76. Swift Trigger 552142 is a noise event
  77. GRB 130327B: Fermi GBM detection
  78. Swift Trigger 552142: a possible GRB
  79. GRB 130327B: gamma-ray detection by AGILE
  80. GRB 130327A: Swift-BAT refined analysis
  81. GRB 130327A: Gemini Observations
  82. GRB 130327A: Weihai optical obsevations
  83. GRB 130327A: Swift/UVOT Upper Limits
  84. Konus-Wind observation of GRB 130325A
  85. GRB 130327A: ISON-NM optical upper limit
  86. GRB 130327A: Enhanced Swift-XRT position
  87. GRB 130327A: RATIR Optical and NIR Observations
  88. GRB 130327A: PAIRITEL NIR Afterglow Candidate
  89. GRB 130325A: Fermi LAT detection
  90. GRB 130327A: Swift detection of a burst
  91. report: GRB 130315A: Zadko observatory - Gingin optical observations
  92. GRB 130305A: Gemini follow-up observations
  93. GRB 130315A: GROND afterglow candidate
  94. GRB 130315A: Swift/UVOT Upper Limits
  95. GRB 130313A: optical upper limit in CrAO
  96. GRB 130313A: optical upper limit in Mondy observatory
  97. GRB 130315A: SALT optical observations
  98. GRB130313A: GTC early optical limits
  99. Swift XRT observations of GRB 130310A
  100. GRB 130315A, Swift-BAT refined analysis

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