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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"

4942 results found.

  1. Further Retractions of previous Swift-BAT triggers
  2. Retractions of previous Swift-BAT triggers
  3. Konus-Wind observation of GRB 061222A
  4. GRB 061222A: Prompt ROTSE-III Optical Limits
  5. GRB 061222: Swift detection of a burst
  6. GRB 061218: TORTOREM optical upper limits
  7. GRB 061217: REM prompt observations
  8. GRB 061217: ROTSE-III Optical Limits
  9. GRB 061217: Swift detection of a short hard burst
  10. GRB 061210: MDM Follow-up Observation
  11. Swift-BAT triggers 238544 and 238546 are not GRBs
  12. GRB 061102: Swift detection of a burst
  13. GRB 061025: Gemini-S observations
  14. GRB061007: Swift UVOT followup observations
  15. GRB 061007: Magellan Spectroscopy
  16. GRB 061007: Swift XRT refined analysis
  17. GRB 061007 - FTS early brightening and power law decay
  18. GRB 061007: Swift detection of a burst with an optical counterpart
  19. GRB 061007: ROTSE-III Detection of Optical Counterpart
  20. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  21. GRB 061002: Swift detection of a burst: CORRECTED CONTENT
  22. GRB 061002: Swift detection of a burst
  23. GRB 060923C: VLT J-band observations
  24. GRB 060923C: Keck Observations
  25. GRB 060912A: Probable Host Galaxy
  26. GRB060904b optical detections (delayed report due to internet outage)
  27. GRB 060904B: RTT150 optical observations
  28. GRB 060904B: Optical observations at Crni Vrh
  29. GRB 060904B BOOTES-IR and 1.5m OSN observations
  30. GRB060904B - SDSS Pre-Burst Observations
  31. GRB 060904: TAROT optical observations
  32. GRB 060904B: Swift detection of a burst with optical counterpart
  33. GRB 060904B: ROTSE-III Detection of Optical Counterpart
  34. GRB 060904: Swift detection of a bright burst
  35. GRB060901: Optical observations
  36. Two bright bursts from SGR 1806-20 detected with IBAS
  37. GRB060825: BOOTES-IR optical observations
  38. GRB 060825: Swift detection of a burst
  39. GRB 060729, SMARTS optical/IR observations
  40. GRB 060814: P200 NIR Observations
  41. GRB 060814: Swift detection of a bright burst
  42. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  43. GRB060807: Optical limiting magnitudes
  44. VLA Upper Limit on Outburst of SGR 1806-20
  45. GRB 060801, optical observation
  46. GRB 060801: Swift detection of a short burst
  47. Swift-BAT trigger 221873 is not a GRB or a Transient
  48. GRB060712: MASTER optical observation
  49. GRB120706: MASTER optical observation
  50. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  51. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  52. GRB060512: near IR observations
  53. GRB 060610: KAIT observations
  54. GRB 070706B: Watcher upper limit
  55. GRB060602A: Swift/UVOT upper limits
  56. GRB 060605: RTT150 optical observations
  57. GRB 060605: Swift-XRT Team refined analysis
  58. GRB 060605: RTT150 optical observations
  59. GRB 060605: Swift detection of a burst with optical counterpart
  60. GRB 060605: ROTSE-III Detection of Optical Counterpart
  61. GRB060502b: optical observations
  62. GRB 060526: REM observations
  63. GRB 060526: MDM-2.4m Observations
  64. GRB 060515: Super-LOTIS Observations
  65. GRB 060515: Swift detection of a burst
  66. GRB 060512: P60 Observations
  67. GRB060512 - SDSS Pre-Burst Observations
  68. GRB060512 Name Correction: LT Afterglow detection
  69. GRB060512: Liverpool Telescope Afterglow detection
  70. GRB060507: optical afterglow detection
  71. GRB060425: new MASTER survey method
  72. GRB060502A, optical observation
  73. GRB 060502A: Swift/UVOT source detection
  74. GRB 060502B: MDM Optical Observation
  75. GRB 060502B: Swift detection of a short burst
  76. GRB060502: Super-LOTIS Observations
  77. GRB 060502: Swift detection of a burst with an optical counterpart
  78. GRB 060428B: KAIT observations
  79. GRB060428A: Swift/UVOT observations.
  80. GRB 060428: Swift detection of a burst
  81. GRB060424: optical afterglow detection
  82. GRB 060421: TTT Observations
  83. Konus-Wind observation of GRB 060418
  84. GRB060418: Optical Observations
  85. GRB060418: Swift XRT Team Refined Analysis
  86. GRB060418: Magellan/MIKE Spectroscopic Redshift
  87. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  88. GRB060403: optical observations
  89. SGR 1900+14: BAT observations
  90. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  91. SGR 1900+14: Swift-BAT detection of a bright outburst
  92. GRB 060322: Confirmation of Swift XRT afterglow
  93. GRB 060211A: optical observation
  94. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  95. GRB 060322: Swift XRT afterglow candidate
  96. GRB 060323: Swift/UVOT Observations
  97. GRB 060323: Swift XRT refined analysis
  98. GRB060218/SN2006aj: optical observations
  99. GRB060319: Swift XRT refined analysis
  100. GRB060319: Swift/UVOT upper limits

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