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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"

28053 results found.

  1. Further ATCA observations of SGR 1806-20
  2. Fourth Epoch VLA observations of SGR 1806-20
  3. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  4. ATCA observations of SGR 1806-20
  5. SGR 1806-20, RHESSI observations of the 041227 giant flare
  6. Third epoch observations of SGR 1806-20 with VLA
  7. Second Epoch VLA observations of SGR 1806-20
  8. Second-epoch VLA observations of SGR 1806-20
  9. SGR1806 VLA Observations
  10. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  11. GRB 041217: Optical observations
  12. GRB041228: Swift-BAT detection of a burst
  13. GRB041219; RXTE ASM Observations
  14. NIR Observations of GRB 041219
  15. GRB041226: Swift-BAT detection of a burst
  16. GRB041223: decay of the afterglow
  17. GRB 041224: near-infrared observations with REM
  18. GRB 041223 Fluence measured by Swift-BAT
  19. GRB041223: optical and NIR observations with REM
  20. Swift-BAT Time History of GRB041219
  21. GRB 041219: TAROT optical observations
  22. GRB 041218: TAROT optical observations
  23. GRB 041223: J-band observations of the afterglow
  24. GRB 041219c: PROMPT Observations
  25. GRB041223: Swift-BAT detection of a bright long burst
  26. GRB 041218: optical observations
  27. GRB 041219 : optical follow-up observations
  28. Deep RAPTOR observations during GRB 041219
  29. GRB 041218 Optical Observations
  30. GRB041219: Continued NIR Observations
  31. GRB 041219 ,optical observation
  32. GRB 041219: Radio Afterglow Detection
  33. GRB 041218 : Radio Observations
  34. GRB 041218: R-band optical observations
  35. GRB041218: optical observations
  36. GRB041219: Confirmed NIR Afterglow
  37. Swift-BAT detection of the bright long burst GRB041219
  38. GRB 041219: Infrared Afterglow Candidate
  39. GRB041219, BVRcIc field calibration
  40. GRB 041219: Infrared Afterglow Candidate
  41. GRB041218, BVRcIc field calibration
  42. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  43. GRB 041219 - A long GRB detected by INTEGRAL
  44. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  45. GRB 041217: PROMPT Observations
  46. GRB 041217: LCO40 Optical Observations and Possible Candidates
  47. GRB 041218 - A long GRB detected by integral
  48. GRB041217: NIR and optical observations with REM
  49. GRB041217: Infrared Observations
  50. GRB041217: The First GRB Located On-Board Swift
  51. GRB041211: Faulkes Telescope continued optical monitoring
  52. Optical Transient in Lynx not a GRB
  53. Optical transient (GRB?) in Lynx
  54. GRB041211: RAPTOR observations
  55. GRB041211: Ashra Prototype optical observation
  56. GRB041211, BVRcIc field calibration
  57. GRB041211,optical observation
  58. GRB 041211: Infrared Observations
  59. GRB 041211: KAIT observations
  60. GRB 041211: Optical follow-up in East Asian region
  61. Triangulation of short GRB 041116 (large error box)
  62. GRB 040924: Afterglow Color
  63. GRB 041006: GETS Optical Afterglow Observation
  64. Summary of the recent bursts from SGR 1806-20
  65. GRB 041006: Optical Observations
  66. GRB041006, late-time optical photometry
  67. GRB041006: RTT150 Optical Observations
  68. HST Observations: XRF 040701 and 040812
  69. Bright bursts from SGR1806-20
  70. GRB 041016: BOOTES-2 simultaneous observation
  71. GRB041006: RTT150 Optical Observations
  72. GRB041016,optical observation
  73. GRB 041016: Optical limits
  74. GRB 041016:Optical limit during first minute
  75. GRB 041015: Optical Observations at Rikubetsu
  76. GRB 041016: Optical limit
  77. GRB 041015 R band observations
  78. GRB040924, BVRcIc field calibration
  79. GRB041015,optical observation
  80. GRB041006: Fading X-ray Afterglow Observed with Chandra
  81. GRB 041015 - A long GRB detected by INTEGRAL
  82. GRB041006: VLT observations of the afterglow and host galaxy
  83. GRB041006: Optical observations and Potential host galaxy
  84. GRB041006, BVRcIc field calibration
  85. GRB 040924: VLT spectroscopy
  86. GRB 041006: SARA afterglow observations
  87. GRB041006, optical observation in CrAO
  88. Search for SN light in XRF 040912 with MEGACAM
  89. GRB 041006: BR observations with VATT
  90. GRB 041006: Redshift confirmed
  91. GRB 041006: Radio Observations
  92. GRB 041006 : optical follow-up observation at Lulin Observatory
  93. GRB041006: Optical photometry and spectroscopy at TNG
  94. GRB 041006: presice astrometry
  95. GRB041006, optical I observation
  96. GRB041006 (=HETE3570): optical observations
  97. ROTSE-IIIa Observations of GRB 041006
  98. GRB041006: MASTER optical observations
  99. GRB041006,optical observation
  100. Konus-Wind observation of a series SGR 1806-20 bursts on 041005

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