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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"

28052 results found.

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

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