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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"

19549 results found.

  1. GRB050215A: ROTSE-III Optical Observations
  2. GRB050209: TAROT optical observations
  3. GRB050209: REM optical observations
  4. GRB 050209 I-band observation
  5. GRB 050209 Optical observations
  6. GRB050209: P60 Optical Observations
  7. GRB 050128: Radio observations
  8. Further analysis of the short Swift-BAT GRB 050202
  9. GRB 050202: Short burst detected by Swift-BAT
  10. GRB 050128 Optical observation with REM
  11. GRB 050128: near-infrared observations with REM
  12. GRB050128,optical observations
  13. GRB050126: Updated Swift XRT Position
  14. GRB 050128: Swift XRT prompt afterglow position
  15. GRB 050124: K-band afterglow observations
  16. GRB050126: MASTER optical limit for KECK OT
  17. GRB050126: MASTER optical observations
  18. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  19. GRB 050124 I-band observation
  20. GRB 050124: NIR Candidates from Keck/NIRC
  21. GRB050124,optical observation
  22. GRB050124: Updated Swift XRT Position and Fluxes
  23. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  24. GRB050123: optical limit 1.8h before GRB
  25. GRB050123,optical observation
  26. GRB 050123: KAIT observations
  27. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  28. GRB050117: MASTER optical observations
  29. MASTER:GRB050117 SWIFT
  30. GRB050117: Swift XRT Position
  31. SGR 1806-20: Further low frequency GMRT results
  32. SGR 1806-20: Further VLA Observations
  33. SGR1806-20: Swift-BAT observations of two additional bursts
  34. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  35. SGR 1806-20 and extragalactic short-duration GRBs
  36. SGR 1806-20, RHESSI observations of the 041227 giant flare
  37. GRB 041217: Optical observations
  38. GRB041223: decay of the afterglow
  39. GRB 041224: near-infrared observations with REM
  40. GRB041223: optical and NIR observations with REM
  41. Swift-BAT Time History of GRB041219
  42. GRB 041219: TAROT optical observations
  43. GRB 041218: TAROT optical observations
  44. GRB 041223: J-band observations of the afterglow
  45. GRB 041219c: PROMPT Observations
  46. GRB041223: Swift-BAT detection of a bright long burst
  47. GRB041220: Swift-BAT burst
  48. Deep RAPTOR observations during GRB 041219
  49. GRB 041218 Optical Observations
  50. GRB041219: Continued NIR Observations
  51. GRB 041219 ,optical observation
  52. GRB 041219: Radio Afterglow Detection
  53. GRB 041218 : Radio Observations
  54. GRB 041218: R-band optical observations
  55. GRB041218: optical observations
  56. GRB041219: Confirmed NIR Afterglow
  57. Swift-BAT detection of the bright long burst GRB041219
  58. GRB 041219: Infrared Afterglow Candidate
  59. GRB041219, BVRcIc field calibration
  60. GRB 041219: Infrared Afterglow Candidate
  61. GRB041218, BVRcIc field calibration
  62. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  63. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  64. GRB 041217: PROMPT Observations
  65. GRB041217: NIR and optical observations with REM
  66. GRB041217: Infrared Observations
  67. GRB041217: The First GRB Located On-Board Swift
  68. GRB041211: Faulkes Telescope continued optical monitoring
  69. Optical transient (GRB?) in Lynx
  70. GRB041211: RAPTOR observations
  71. GRB041211: Ashra Prototype optical observation
  72. GRB041211, BVRcIc field calibration
  73. GRB041211,optical observation
  74. GRB 041211: Infrared Observations
  75. GRB 041211: KAIT observations
  76. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  77. GRB 040924: Afterglow Color
  78. GRB 041006: GETS Optical Afterglow Observation
  79. GRB 041006: Optical Observations
  80. GRB041006, late-time optical photometry
  81. GRB041006: RTT150 Optical Observations
  82. GRB 041016: BOOTES-2 simultaneous observation
  83. GRB041006: RTT150 Optical Observations
  84. GRB041016,optical observation
  85. GRB 041016: Optical limits
  86. GRB 041016:Optical limit during first minute
  87. GRB 041016: Optical limit
  88. GRB 041015 R band observations
  89. GRB040924, BVRcIc field calibration
  90. GRB041015,optical observation
  91. GRB041006: Fading X-ray Afterglow Observed with Chandra
  92. GRB 041015 - A long GRB detected by INTEGRAL
  93. GRB041006: Optical observations and Potential host galaxy
  94. GRB041006, BVRcIc field calibration
  95. GRB 041006: SARA afterglow observations
  96. GRB041006, optical observation in CrAO
  97. Search for SN light in XRF 040912 with MEGACAM
  98. GRB 041006: BR observations with VATT
  99. GRB041006, optical I observation
  100. ROTSE-IIIa Observations of GRB 041006

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