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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').
Advanced Search

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"

18361 results found.

  1. XMM-Newton Images of GRB 050223
  2. GRB 050219b: candidate NIR afterglow
  3. GRB050223 XMM-Newton observation
  4. GRB050223: ROTSE-III Optical Observations
  5. GRB 050223: Swift XRT Position
  6. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  7. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  8. GRB 050219a: Optical observations from LCO
  9. GRB 050219b: Optical and near-IR observations from LCO
  10. GRB 050215b: XRT confirmation of IR afterglow candidate
  11. GRB050215b: P60 Optical Observations
  12. GRB 050215b: Swift XRT Source Variability
  13. GRB 050215b, BOOTES-2 simultaneous optical observations
  14. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  15. GRB050215A: ROTSE-III Optical Observations
  16. GRB050209: TAROT optical observations
  17. GRB050209: REM optical observations
  18. GRB 050209 I-band observation
  19. GRB 050209 Optical observations
  20. GRB050209: P60 Optical Observations
  21. GRB 050128: Radio observations
  22. GRB 050202: Short burst detected by Swift-BAT
  23. GRB 050128 Optical observation with REM
  24. GRB 050128: near-infrared observations with REM
  25. GRB050128,optical observations
  26. GRB 050128: Swift XRT prompt afterglow position
  27. GRB050126: MASTER optical limit for KECK OT
  28. GRB050126: Burst Parameters Measured by BAT
  29. GRB050126: MASTER optical observations
  30. GRB 050124 I-band observation
  31. GRB 050124: NIR Candidates from Keck/NIRC
  32. GRB050124,optical observation
  33. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  34. GRB050123,optical observation
  35. GRB 050123: KAIT observations
  36. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  37. GRB050117: MASTER optical observations
  38. MASTER:GRB050117 SWIFT
  39. GRB050117: Swift XRT Position
  40. SGR 1806-20: Further low frequency GMRT results
  41. SGR1806-20: Swift-BAT observations of two additional bursts
  42. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  43. SGR 1806-20, RHESSI observations of the 041227 giant flare
  44. GRB 041217: Optical observations
  45. GRB041223: decay of the afterglow
  46. GRB 041224: near-infrared observations with REM
  47. GRB041223: optical and NIR observations with REM
  48. GRB 041219: TAROT optical observations
  49. GRB 041218: TAROT optical observations
  50. GRB 041223: J-band observations of the afterglow
  51. GRB 041219c: PROMPT Observations
  52. GRB041223: Swift-BAT detection of a bright long burst
  53. GRB 041218 Optical Observations
  54. GRB041219: Continued NIR Observations
  55. GRB 041219 ,optical observation
  56. GRB 041219: Radio Afterglow Detection
  57. GRB 041218 : Radio Observations
  58. GRB 041218: R-band optical observations
  59. GRB041218: optical observations
  60. GRB041219: Confirmed NIR Afterglow
  61. GRB041218: Continued P60 Optical Observations
  62. Swift-BAT detection of the bright long burst GRB041219
  63. GRB 041219: Infrared Afterglow Candidate
  64. GRB041219, BVRcIc field calibration
  65. GRB 041219: Infrared Afterglow Candidate
  66. GRB041218, BVRcIc field calibration
  67. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  68. GRB 041219 - A long GRB detected by INTEGRAL
  69. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  70. GRB 041217: PROMPT Observations
  71. GRB041217: NIR and optical observations with REM
  72. GRB041217: Infrared Observations
  73. GRB041217: The First GRB Located On-Board Swift
  74. GRB041211: Faulkes Telescope continued optical monitoring
  75. Optical transient (GRB?) in Lynx
  76. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  77. GRB041211: RAPTOR observations
  78. GRB041211: Ashra Prototype optical observation
  79. GRB041211, BVRcIc field calibration
  80. GRB041211,optical observation
  81. GRB 041211: Infrared Observations
  82. GRB 041211: KAIT observations
  83. GRB 040924: Afterglow Color
  84. GRB 041006: GETS Optical Afterglow Observation
  85. GRB 041006: Optical Observations
  86. GRB041006, late-time optical photometry
  87. GRB041006: RTT150 Optical Observations
  88. GRB041015 : Multi epoch optical observations
  89. GRB 041016: BOOTES-2 simultaneous observation
  90. GRB041006: RTT150 Optical Observations
  91. GRB041016,optical observation
  92. GRB 041016: Optical limits
  93. GRB 041016:Optical limit during first minute
  94. GRB 041016: Optical limit
  95. GRB 041015 R band observations
  96. GRB040924, BVRcIc field calibration
  97. GRB041015,optical observation
  98. GRB041006: Fading X-ray Afterglow Observed with Chandra
  99. GRB041006: Optical observations and Potential host galaxy
  100. GRB041006, BVRcIc field calibration

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