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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"

28048 results found.

  1. Third epoch observations of SGR 1806-20 with VLA
  2. Second Epoch VLA observations of SGR 1806-20
  3. Second-epoch VLA observations of SGR 1806-20
  4. SGR1806 VLA Observations
  5. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  6. GRB 041217: Optical observations
  7. GRB041228: Swift-BAT detection of a burst
  8. GRB041219; RXTE ASM Observations
  9. NIR Observations of GRB 041219
  10. GRB041226: Swift-BAT detection of a burst
  11. GRB041223: decay of the afterglow
  12. GRB 041224: near-infrared observations with REM
  13. GRB 041223 Fluence measured by Swift-BAT
  14. GRB041223: optical and NIR observations with REM
  15. Swift-BAT Time History of GRB041219
  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: Swift-BAT detection of a bright long burst
  21. GRB 041218: optical observations
  22. GRB 041219 : optical follow-up observations
  23. Deep RAPTOR observations during GRB 041219
  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 - A long GRB detected by INTEGRAL
  39. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  40. GRB 041217: PROMPT Observations
  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: Infrared Observations
  45. GRB041217: The First GRB Located On-Board Swift
  46. GRB041211: Faulkes Telescope continued optical monitoring
  47. Optical Transient in Lynx not a GRB
  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. Bright bursts from SGR1806-20
  65. GRB 041016: BOOTES-2 simultaneous observation
  66. GRB041006: RTT150 Optical Observations
  67. GRB041016,optical observation
  68. GRB 041016: Optical limits
  69. GRB 041016:Optical limit during first minute
  70. GRB 041015: Optical Observations at Rikubetsu
  71. GRB 041016: Optical limit
  72. GRB 041015 R band observations
  73. GRB040924, BVRcIc field calibration
  74. GRB041015,optical observation
  75. GRB041006: Fading X-ray Afterglow Observed with Chandra
  76. GRB 041015 - A long GRB detected by INTEGRAL
  77. GRB041006: VLT observations of the afterglow and host galaxy
  78. GRB041006: Optical observations and Potential host galaxy
  79. GRB041006, BVRcIc field calibration
  80. GRB 040924: VLT spectroscopy
  81. GRB 041006: SARA afterglow observations
  82. GRB041006, optical observation in CrAO
  83. Search for SN light in XRF 040912 with MEGACAM
  84. GRB 041006: BR observations with VATT
  85. GRB 041006: Redshift confirmed
  86. GRB 041006: Radio Observations
  87. GRB 041006 : optical follow-up observation at Lulin Observatory
  88. GRB041006: Optical photometry and spectroscopy at TNG
  89. GRB 041006: presice astrometry
  90. GRB041006, optical I observation
  91. GRB041006 (=HETE3570): optical observations
  92. ROTSE-IIIa Observations of GRB 041006
  93. GRB041006: MASTER optical observations
  94. GRB041006,optical observation
  95. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  96. GRB041006: Fading of optical afterglow candidate
  97. GRB 041006: Optical afterglow candidate
  98. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  99. XRF 020903: Observations of the Host Galaxy
  100. radio observations, GRB 040924

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