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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"

23562 results found.

  1. SGR 1806-20, RHESSI observations of the 041227 giant flare
  2. Second-epoch VLA observations of SGR 1806-20
  3. SGR1806 VLA Observations
  4. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  5. GRB 041217: Optical observations
  6. GRB041228: ROTSE-III Optical Observations
  7. GRB041228: Swift-BAT detection of a burst
  8. GRB041219; RXTE ASM Observations
  9. GRB041226: ROTSE-III Optical Observations
  10. GRB041226: Swift-BAT detection of a burst
  11. GRB041223: decay of the afterglow
  12. GRB041224: ROTSE-III Optical Observations
  13. GRB 041224: near-infrared observations with REM
  14. GRB041224: Swift-BAT detection of a soft burst
  15. GRB041223: optical and NIR observations with REM
  16. GRB 041219: TAROT optical observations
  17. GRB 041218: TAROT optical observations
  18. GRB 041223: J-band observations of the afterglow
  19. GRB 041219c: PROMPT Observations
  20. GRB041223: ROTSE-III Optical Observations
  21. GRB041223: Swift-BAT detection of a bright long burst
  22. GRB 041218: optical observations
  23. GRB 041219 : optical follow-up observations
  24. GRB 041218 Optical Observations
  25. GRB041219: Continued NIR Observations
  26. GRB 041219 ,optical observation
  27. GRB 041219: Radio Afterglow Detection
  28. GRB 041218 : Radio Observations
  29. GRB 041218: R-band optical observations
  30. GRB041218: optical observations
  31. GRB041219: Confirmed NIR Afterglow
  32. Swift-BAT detection of the bright long burst GRB041219
  33. GRB 041219: Infrared Afterglow Candidate
  34. GRB041219, BVRcIc field calibration
  35. GRB 041219: Infrared Afterglow Candidate
  36. GRB041218, BVRcIc field calibration
  37. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  38. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  39. GRB 041217: PROMPT Observations
  40. GRB041217: optical limit 30 min after GRB
  41. GRB 041217: LCO40 Optical Observations and Possible Candidates
  42. GRB 041218 - A long GRB detected by integral
  43. GRB041217: NIR and optical observations with REM
  44. GRB041217: P60 Optical Observations
  45. GRB041217: Infrared Observations
  46. GRB041217: The First GRB Located On-Board Swift
  47. GRB041211: Faulkes Telescope continued optical monitoring
  48. Optical transient (GRB?) in Lynx
  49. GRB041211: RAPTOR observations
  50. GRB041211: Ashra Prototype optical observation
  51. GRB041211, BVRcIc field calibration
  52. GRB041211,optical observation
  53. GRB 041211: Infrared Observations
  54. GRB 041211: KAIT observations
  55. GRB 041211: Optical follow-up in East Asian region
  56. Triangulation of short GRB 041116 (large error box)
  57. GRB 040924: Afterglow Color
  58. GRB 041006: GETS Optical Afterglow Observation
  59. Summary of the recent bursts from SGR 1806-20
  60. GRB 041006: Optical Observations
  61. GRB041006, late-time optical photometry
  62. GRB041006: RTT150 Optical Observations
  63. HST Observations: XRF 040701 and 040812
  64. GRB 041016: BOOTES-2 simultaneous observation
  65. GRB041006: RTT150 Optical Observations
  66. GRB041016,optical observation
  67. GRB 041016: Optical limits
  68. GRB 041016:Optical limit during first minute
  69. GRB 041016: Optical limit
  70. GRB 041015 R band observations
  71. GRB040924, BVRcIc field calibration
  72. GRB041015,optical observation
  73. GRB041006: Fading X-ray Afterglow Observed with Chandra
  74. GRB 041015 - A long GRB detected by INTEGRAL
  75. GRB041006: Optical observations and Potential host galaxy
  76. GRB041006, BVRcIc field calibration
  77. GRB 041006: SARA afterglow observations
  78. GRB041006, optical observation in CrAO
  79. Search for SN light in XRF 040912 with MEGACAM
  80. GRB 040916: Afterglow Color at Early Times
  81. GRB 041006: BR observations with VATT
  82. GRB 041006 : Optical follow-up observation at TAROT
  83. GRB041006, optical I observation
  84. GRB041006 (=HETE3570): optical observations
  85. ROTSE-IIIa Observations of GRB 041006
  86. GRB041006: MASTER optical observations
  87. GRB041006,optical observation
  88. GRB041006: Fading of optical afterglow candidate
  89. GRB 041006: Optical afterglow candidate
  90. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  91. XRF 020903: Observations of the Host Galaxy
  92. radio observations, GRB 040924
  93. GRB040929,optical observation
  94. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  95. GRB040924,optical observation
  96. GRB040924,optical observation
  97. GRB040924: KAIT observations
  98. GRB 040924: WSRT Radio Observations
  99. GRB 040924: Subaru NIR observation
  100. GRB 040924, optical follow-up

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