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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"

6094 results found.

  1. GRB 060719: VLT/ISAAC observations
  2. GRB 060719: XRT refined analysis
  3. GRB 060719: LCO optical observations
  4. GRB 060717: Swift XRT refined analysis
  5. GRB 060714: OA fading and a possible host detection
  6. GRB 060714: Swift XRT refined analysis
  7. GRB 060712: XRT refined analysis
  8. GRB 060712: XRT refined position
  9. GRB 060708: Swift-XRT refined analysis
  10. GRB 060707: Swift-XRT refined analysis
  11. GRB050326: Host Galaxy Candidates
  12. GRB050124: Possible Host Galaxy
  13. GRB050223: Host Galaxy
  14. GRB060512: near IR observations
  15. GRB060614: Swift-XRT refined analysis
  16. GRB 060602A: Swift/XRT analysis
  17. GRB 060605: Swift-XRT Team refined analysis
  18. GRB 060604: Swift-XRT Team refined analysis
  19. GRB 060602B: RTT150 optical observations
  20. GRB 060502A: Optical afterglow observations
  21. GRB 060526: Break in X-ray light curve
  22. GRB 060526: RTT150 optical observations
  23. XMM-Newton observation of GRB060510b
  24. GRB 060515: NIR observation
  25. GRB060515: P200 NIR Observations
  26. GRB 060515: Swift/XRT Team refined analysis
  27. GRB 060515: Swift/XRT position
  28. GRB 060512: Subaru NIR observation
  29. GRB060512: Swift XRT Team refined analysis
  30. GRB 060512: 1.54m Kuiper Observations
  31. GRB 060512: Detection of NIR afterglow
  32. GRB 060505: X-ray afterglow - Correction -
  33. GRB 060505: X-ray afterglow
  34. GRB060510B: Swift XRT refined analysis
  35. GRB060510A: XRT refined analysis
  36. GRB 060510B: Swift detection of a burst
  37. GRB060502B: improvement in the XRT afterglow position
  38. GRB 060505: Swift XRT Team Refined Analysis
  39. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  40. GRB 060505: Swift XRT afterglow canditate position
  41. GRB 060502b: Second epoch Gemini observations
  42. GRB060502B: Swift XRT Team refined analysis
  43. GRB060502: Swift-XRT refined analysis
  44. GRB060428B: Swift XRT Team refined analysis
  45. GRB 060421: Swift-XRT refined analysis
  46. Erratum of GCN 4983 for GRB 060418 IR follow-up
  47. GRB 060418 : IR afterglow observations
  48. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  49. GRB060418: Swift XRT Team Refined Analysis
  50. GRB 060413: REM NIR Observations
  51. GRB060403: XRT refined analysis
  52. GRB060218, optical observations
  53. GRB 060322: Confirmation of Swift XRT afterglow
  54. GRB 060322: Swift XRT afterglow candidate
  55. GRB 060313: early afterglow NIR upper limits with REM
  56. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  57. GRB060218: SARA Observations of SN2006aj
  58. GRB 060312: Refined analysis of the Swift-BAT burst
  59. GRB 060312: Swift XRT team refined analysis
  60. GRB060306: APO Ks-band Imaging Observations
  61. GRB 060306: SOAR Ks Observations
  62. GRB060218: analysis of the XMM-Newton observation
  63. GRB 060306: Swift-BAT refined analysis
  64. GRB 060223B: Swift XRT possible afterglow
  65. GRB 060223: Swift-BAT refined analysis
  66. GRB 060219: Swift-XRT Team refined analysis
  67. GRB 051221B: Swift-XRT Team Refined Analysis
  68. GRB 060218A: ROTSE-III Possible Optical Flare
  69. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  70. GRB 060211A: Further refined analysis of the Swift burst
  71. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  72. GRB 060210: Further refined analysis of the Swift-BAT burst
  73. GRB 060211B: Swift-XRT Team refined analysis
  74. GRB060211b: optical observation
  75. GRB060210: Swift XRT Refined Analysis
  76. GRB 060206: near-infrared observations (JK' imaging)
  77. GRB 060206: IR Detection of the Afterglow
  78. GRB 060206 : Lulin optical observations
  79. GRB060206: SARA Detection
  80. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  81. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  82. Swift XRT Observation of GRB 060204C
  83. GRB060204B: Swift XRT Team Refined Analysis
  84. GRB 060203: IR Counterpart
  85. GRB060203: Observations with SARA
  86. Swift BAT Trigger 180151: Swift XRT source detection
  87. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  88. GRB 060202: Refined analysis of the Swift-BAT burst
  89. GRB 051211A: MDM Observations
  90. GRB 060121: Confirmation of NIR Afterglow
  91. GRB 060123: Swift refined analysis of an unusual GRB
  92. GRB060105: refined analysis of the Suzaku observation
  93. GRB 060121: Probable Detection of NIR Afterglow
  94. Konus-Wind observation of GRB 060124
  95. GRB060124: detailed XRT analysis
  96. GRB060123: Optical and IR Imaging
  97. GRB 060123: P200 Observations
  98. GRB 060124: R band Observations
  99. GRB 060123: Swift detection of a very long, faint burst
  100. GRB 060124: Confirmation of the Afterglow

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