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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28056 results found.

  1. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  2. Further VLA observations of SGR 1806-20
  3. SGR 1806-20 and extragalactic short-duration GRBs
  4. Further ATCA observations of SGR 1806-20
  5. Fourth Epoch VLA observations of SGR 1806-20
  6. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  7. ATCA observations of SGR 1806-20
  8. SGR 1806-20, RHESSI observations of the 041227 giant flare
  9. Third epoch observations of SGR 1806-20 with VLA
  10. Second Epoch VLA observations of SGR 1806-20
  11. Second-epoch VLA observations of SGR 1806-20
  12. SGR1806 VLA Observations
  13. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  14. GRB 041217: Optical observations
  15. GRB041228: Swift-BAT detection of a burst
  16. GRB041219; RXTE ASM Observations
  17. NIR Observations of GRB 041219
  18. GRB041226: Swift-BAT detection of a burst
  19. GRB041223: decay of the afterglow
  20. GRB 041224: near-infrared observations with REM
  21. GRB 041223 Fluence measured by Swift-BAT
  22. GRB041223: optical and NIR observations with REM
  23. Swift-BAT Time History of GRB041219
  24. GRB 041219: TAROT optical observations
  25. GRB 041218: TAROT optical observations
  26. GRB 041223: J-band observations of the afterglow
  27. GRB 041219c: PROMPT Observations
  28. GRB041223: Swift-BAT detection of a bright long burst
  29. GRB 041218: optical observations
  30. GRB 041219 : optical follow-up observations
  31. Deep RAPTOR observations during GRB 041219
  32. GRB 041218 Optical Observations
  33. GRB041219: Continued NIR Observations
  34. GRB 041219 ,optical observation
  35. GRB 041219: Radio Afterglow Detection
  36. GRB 041218 : Radio Observations
  37. GRB 041218: R-band optical observations
  38. GRB041218: optical observations
  39. GRB041219: Confirmed NIR Afterglow
  40. Swift-BAT detection of the bright long burst GRB041219
  41. GRB 041219: Infrared Afterglow Candidate
  42. GRB041219, BVRcIc field calibration
  43. GRB 041219: Infrared Afterglow Candidate
  44. GRB041218, BVRcIc field calibration
  45. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  46. GRB 041219 - A long GRB detected by INTEGRAL
  47. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  48. GRB 041217: PROMPT Observations
  49. GRB 041217: LCO40 Optical Observations and Possible Candidates
  50. GRB 041218 - A long GRB detected by integral
  51. GRB041217: NIR and optical observations with REM
  52. GRB041217: Infrared Observations
  53. GRB041217: The First GRB Located On-Board Swift
  54. GRB041211: Faulkes Telescope continued optical monitoring
  55. Optical Transient in Lynx not a GRB
  56. Optical transient (GRB?) in Lynx
  57. GRB041211: RAPTOR observations
  58. GRB041211: Ashra Prototype optical observation
  59. GRB041211, BVRcIc field calibration
  60. GRB041211,optical observation
  61. GRB 041211: Infrared Observations
  62. GRB 041211: KAIT observations
  63. GRB 041211: Optical follow-up in East Asian region
  64. Triangulation of short GRB 041116 (large error box)
  65. GRB 040924: Afterglow Color
  66. GRB 041006: GETS Optical Afterglow Observation
  67. Summary of the recent bursts from SGR 1806-20
  68. GRB 041006: Optical Observations
  69. GRB041006, late-time optical photometry
  70. GRB041006: RTT150 Optical Observations
  71. HST Observations: XRF 040701 and 040812
  72. Bright bursts from SGR1806-20
  73. GRB 041016: BOOTES-2 simultaneous observation
  74. GRB041006: RTT150 Optical Observations
  75. GRB041016,optical observation
  76. GRB 041016: Optical limits
  77. GRB 041016:Optical limit during first minute
  78. GRB 041015: Optical Observations at Rikubetsu
  79. GRB 041016: Optical limit
  80. GRB 041015 R band observations
  81. GRB040924, BVRcIc field calibration
  82. GRB041015,optical observation
  83. GRB041006: Fading X-ray Afterglow Observed with Chandra
  84. GRB 041015 - A long GRB detected by INTEGRAL
  85. GRB041006: VLT observations of the afterglow and host galaxy
  86. GRB041006: Optical observations and Potential host galaxy
  87. GRB041006, BVRcIc field calibration
  88. GRB 040924: VLT spectroscopy
  89. GRB 041006: SARA afterglow observations
  90. GRB041006, optical observation in CrAO
  91. Search for SN light in XRF 040912 with MEGACAM
  92. GRB 041006: BR observations with VATT
  93. GRB 041006: Redshift confirmed
  94. GRB 041006: Radio Observations
  95. GRB 041006 : optical follow-up observation at Lulin Observatory
  96. GRB041006: Optical photometry and spectroscopy at TNG
  97. GRB 041006: presice astrometry
  98. GRB041006, optical I observation
  99. GRB041006 (=HETE3570): optical observations
  100. ROTSE-IIIa Observations of GRB 041006

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