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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"

20547 results found.

  1. GRB 110921A: Swift detection of a burst
  2. GRB 110915B : X-ray afterglow confirmation
  3. GRB 110918A: Swift/UVOT Detection of the Optical Counterpart
  4. GRB 110918A optical observation
  5. GRB 110918A: GROND detection of the afterglow candidate
  6. GRB 110918A: INT optical detection of Swift candidate afterglow
  7. GRB 110918A: Swift-XRT observations
  8. Konus-Wind observation of GRB 110918A
  9. MAXI/GSC detection of a short soft X-ray transient
  10. Swift detection of short bursts from PSR J1647-4552
  11. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  12. GRB 110915A: Swift/UVOT Upper Limits
  13. GRB 110915B: Swift/UVOT Upper Limits
  14. GRB 110915A: GROND Upper limits
  15. GRB 110915B: Afterglow candidate from OSN
  16. GRB 110915A: Deep Near-IR Limits from Magellan
  17. GRB 110915B: XRT afterglow candidate
  18. GRB 110915A: Deep Gemini-South i/z-band imaging
  19. GRB110915A MITSuME Okayama J-band upper-limit
  20. GRB 110915A: MITSuME Okayama and Ishigakijima Optical upper limits
  21. GRB 110915A: NOT observations
  22. GRB 110915A: 1.23m CAHA I-band observations
  23. GRB 110915B: SuperAGILE localization of a long GRB
  24. GRB 110915A: Enhanced Swift-XRT position
  25. GRB 110915A: GMG optical upper limit
  26. GRB 110915A: MASTER-Net early limit
  27. GRB 110915A: Swift detection of a burst
  28. GRB 110825A: Further Swift/XRT Observations
  29. GRB 110731A: SAO RAS and Terskol observations
  30. GRB 110903A: Swift/UVOT Upper Limits
  31. GRB 110903A: Swift-XRT observations
  32. GRB 110820A: optical upper limit
  33. Trigger 502024: Swift detection of KS 1741-293
  34. GRB 110825A: GMG optical observation
  35. GRB 110827A, Swift-BAT refined analysis
  36. GRB 110825A: optical afterglow candidate
  37. GRB 110825A: field inspection and possible host galaxy
  38. GRB110825A: Swift target of opportunity observation
  39. IPN triangulation of GRB110825A (very intense, long-duration)
  40. Swift-BAT Trigger 501485 is noise
  41. Konus-Wind observation of GRB 110820B
  42. IPN triangulation of GRB 110820B (very long duration, extremely intense)
  43. GRB 110820A: Swift/UVOT Upper Limits
  44. GRB110820A: MITSuME Ishigakijima Optical Upper Limits
  45. GRB 110820A: Enhanced Swift-XRT position
  46. GRB 110820A: CrAO optical upper limit
  47. GRB 110820A: Swift detection of a burst
  48. GRB 110818A: Swift/UVOT Upper Limits
  49. GRB 110818A: Enhanced Swift-XRT position
  50. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  51. GRB 110818A: Swift-XRT refined Analysis
  52. GRB 110815A: Swift-XRT and UVOT refined Analysis
  53. GRB 110818A: Swift detection of a burst
  54. GRB 110801A: optical observations at Mt. Terskol observatory
  55. Konus-Wind observation of GRB 110808B
  56. Konus-Wind observation of GRB 110808A
  57. RXTE Discovery of the Spin Period of Swift J1834.9-0846
  58. GRB 110808A: Swift/UVOT Detection
  59. GRB 110808A: Enhanced Swift-XRT position
  60. GRB 110808A: Swift detection of a burst with optical counterpart
  61. GRB 110807A: SAO RAS observations
  62. GRB 110807A: Swift detection of a burst or a posible new SGR
  63. GRB 110726A: two epochs of SAO RAS optical observations
  64. IPN triangulation of GRB110802A (short/hard burst)
  65. GRB 110801A: optical observations in CrAO
  66. EVLA observation for Fermi burst GRB 110721A
  67. GRB 110726A: Swift-XRT refined Analysis
  68. GRB 110801A: SAO RAS optical observations
  69. GRB110801A: MITSuME Ishigakijima Optical Observation at 1 day after the burst
  70. Swift/UVOT observations of GRB110801A
  71. GRB110801A: MITSuME Ishigakijima Optical Observation
  72. GRB 110801A: Enhanced Swift-XRT position
  73. GRB 110801A: Swift detection of a burst with an optical counterpart
  74. GRB110731A: MITSuME Ishigakijima Optical Upper Limits
  75. GRB110731A: Swift/UVOT Observations
  76. GRB 110731A: NOT photometry
  77. GRB 110731A: Enhanced Swift-XRT position
  78. GRB 110731A: Swift detection of a burst with an optical counterpart
  79. INTEGRAL Weak trigger #6331: GRT Optical Observation
  80. GRB 110721A: Swift observations of afterglow candidate
  81. GRB 110726A: optical upper limit in CrAO
  82. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  83. GRB110726A: MITSuME Ishigakijima Optical Observation
  84. GRB 110726A: Further Swift/UVOT Observations
  85. GRB110726A: Gemini-N tentative redshift
  86. GRB 110726A: Enhanced Swift-XRT position
  87. GRB 110726A: Swift/UVOT Detection
  88. GRB 110726A: Swift detection of a burst
  89. IPN triangulation of GRB 110721A
  90. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  91. GRB 110721A: potential counterpart candidate
  92. GRB 110721A: Fermi-LAT detection
  93. Recent GCN/Swift-BAT Slew Burst Position notices are due to playback debugging
  94. GRB 110719A: GRT Optical Observation
  95. GRB 110719A: optical limit by "Pi of the Sky"
  96. GRB 110719A: z-band upper limit
  97. Swift/UVOT observations of GRB110719A
  98. Swift J1822.3-1606 : Fermi GBM observation
  99. GRB 110719A: optical upper limit
  100. GRB 110719A: Enhanced Swift-XRT position

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