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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"

24641 results found.

  1. GRB041219; RXTE ASM Observations
  2. NIR Observations of GRB 041219
  3. GRB041226: Swift-BAT detection of a burst
  4. GRB041223: decay of the afterglow
  5. GRB 041224: near-infrared observations with REM
  6. GRB 041223 Fluence measured by Swift-BAT
  7. GRB041223: optical and NIR observations with REM
  8. Swift-BAT Time History of GRB041219
  9. GRB 041219: TAROT optical observations
  10. GRB 041218: TAROT optical observations
  11. GRB 041223: J-band observations of the afterglow
  12. GRB 041219c: PROMPT Observations
  13. GRB041223: Swift-BAT detection of a bright long burst
  14. GRB 041218: optical observations
  15. GRB 041219 : optical follow-up observations
  16. Deep RAPTOR observations during GRB 041219
  17. GRB 041218 Optical Observations
  18. GRB041219: Continued NIR Observations
  19. GRB 041219 ,optical observation
  20. GRB 041219: Radio Afterglow Detection
  21. GRB 041218 : Radio Observations
  22. GRB 041218: R-band optical observations
  23. GRB041218: optical observations
  24. GRB041219: Confirmed NIR Afterglow
  25. Swift-BAT detection of the bright long burst GRB041219
  26. GRB 041219: Infrared Afterglow Candidate
  27. GRB041219, BVRcIc field calibration
  28. GRB 041219: Infrared Afterglow Candidate
  29. GRB041218, BVRcIc field calibration
  30. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  31. GRB 041219 - A long GRB detected by INTEGRAL
  32. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  33. GRB 041217: PROMPT Observations
  34. GRB 041217: LCO40 Optical Observations and Possible Candidates
  35. GRB 041218 - A long GRB detected by integral
  36. GRB041217: NIR and optical observations with REM
  37. GRB041217: Infrared Observations
  38. GRB041217: The First GRB Located On-Board Swift
  39. GRB041211: Faulkes Telescope continued optical monitoring
  40. Optical Transient in Lynx not a GRB
  41. Optical transient (GRB?) in Lynx
  42. GRB041211: RAPTOR observations
  43. GRB041211: Ashra Prototype optical observation
  44. GRB041211, BVRcIc field calibration
  45. GRB041211,optical observation
  46. GRB 041211: Infrared Observations
  47. GRB 041211: KAIT observations
  48. GRB 041211: Optical follow-up in East Asian region
  49. Triangulation of short GRB 041116 (large error box)
  50. GRB 040924: Afterglow Color
  51. GRB 041006: GETS Optical Afterglow Observation
  52. Summary of the recent bursts from SGR 1806-20
  53. GRB 041006: Optical Observations
  54. GRB041006, late-time optical photometry
  55. GRB041006: RTT150 Optical Observations
  56. HST Observations: XRF 040701 and 040812
  57. Bright bursts from SGR1806-20
  58. GRB 041016: BOOTES-2 simultaneous observation
  59. GRB041006: RTT150 Optical Observations
  60. GRB041016,optical observation
  61. GRB 041016: Optical limits
  62. GRB 041016:Optical limit during first minute
  63. GRB 041015: Optical Observations at Rikubetsu
  64. GRB 041016: Optical limit
  65. GRB 041015 R band observations
  66. GRB040924, BVRcIc field calibration
  67. GRB041015,optical observation
  68. GRB041006: Fading X-ray Afterglow Observed with Chandra
  69. GRB 041015 - A long GRB detected by INTEGRAL
  70. GRB041006: VLT observations of the afterglow and host galaxy
  71. GRB041006: Optical observations and Potential host galaxy
  72. GRB041006, BVRcIc field calibration
  73. GRB 040924: VLT spectroscopy
  74. GRB 041006: SARA afterglow observations
  75. GRB041006, optical observation in CrAO
  76. Search for SN light in XRF 040912 with MEGACAM
  77. GRB 041006: BR observations with VATT
  78. GRB 041006: Redshift confirmed
  79. GRB 041006: Radio Observations
  80. GRB 041006 : optical follow-up observation at Lulin Observatory
  81. GRB041006: Optical photometry and spectroscopy at TNG
  82. GRB 041006: presice astrometry
  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. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  89. GRB041006: Fading of optical afterglow candidate
  90. GRB 041006: Optical afterglow candidate
  91. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  92. XRF 020903: Observations of the Host Galaxy
  93. radio observations, GRB 040924
  94. GRB040929,optical observation
  95. GRB040924,optical observation
  96. GRB040924,optical observation
  97. GRB 040924: detection of possible host galaxy by Subaru
  98. GRB040924: KAIT observations
  99. GRB040924 : Optical candidate observations at Lulin observatory
  100. GRB040924 : Optical candidate observations at Lulin observatory

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