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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"

19221 results found.

  1. GRB 070126: Swift/UVOT refined analysis
  2. Konus-Wind observation of GRB 070125
  3. GRB 070125: optical observations
  4. GRB 070126: VLT observations
  5. GRB 070124: Suzaku WAM observation of the prompt emissions
  6. GRB 070126, Swift-BAT refined analysis of a very faint burst
  7. GRB070125: Optical observation by Kanata
  8. GRB070124: Swift-XRT Observation
  9. Possible GRB 070126: Swift/UVOT Upper Limit
  10. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  11. GRB 070125: Xinglong TNT optical observations
  12. GRB070125: Swift-XRT Refined Analysis
  13. GRB 070125: SARA detection in R
  14. GRB 070125: P60 Optical Afterglow Candidate
  15. GRB 070126?: Swift detection of a possible burst
  16. GRB070125 redshift request
  17. RHESSI Spectrum of GRB070125
  18. Konus-Wind observation of short hard GRB 070124
  19. IPN localization of GRB070124 (short duration, hard spectrum)
  20. GRB 070110: optical break
  21. GRB 070107: Suzaku WAM observation of the prompt emission
  22. GRB 070110, Swift-BAT refined analysis
  23. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  24. GRB 070110: Swift detection of a burst with a possible optical afterglow
  25. GRB 070107: Swift detection of a burst
  26. VLA observation of GRB 061222B
  27. VLA detection of GRB 061222A
  28. GRB070103: APO SPIcam i' and z' limits
  29. GRB070103: KPNO 4m+FLAMINGOS J limit
  30. GRB 070103: Swift/UVOT Upper limits
  31. GRB 070103: NOT observations
  32. GRB 070103: TAROT Calern observatory optical observations
  33. erratum : SDSS Pre-burst Observations of GRB061126
  34. Konus-Wind observation of GRB 061222A
  35. GRB 061210: Swift/XRT Astrometry Correction
  36. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  37. GRB 061222A: Xinglong Optical Limit
  38. GRB 061222A: Gemini Afterglow Candidate
  39. GRB 061222B, Swift-BAT refined analysis
  40. GRB061222A Swift/UVOT: Upper Limits
  41. GRB 061222B: Swift/UVOT Upper limits
  42. GRB 061222B: Observation with the KANATA 1.5m telescope
  43. GRB 061222A: Observation with the KANATA 1.5m telescope
  44. GRB 061222B: BOOTES-IR optical observations
  45. GRB 061222B: SARA upper limit
  46. GRB 061222B: REM NIR/optical observations
  47. GRB 061222B: TAROT La Silla observatory optical observations
  48. GRB 061222B: Swift detection of a burst
  49. GRB 061222A: Prompt ROTSE-III Optical Limits
  50. GRB 061222: Swift detection of a burst
  51. GRB 061218: TAROT La Silla observatory optical observations
  52. GRB 061217: TAROT Calern observatory optical observations
  53. GRB 061218: TORTOREM optical upper limits
  54. GRB 061218, Swift-BAT refined analysis
  55. GRB061217: VLT NIR observations
  56. GRB 061218, SMARTS optical/IR observations
  57. GRB 061218: REM prompt observations
  58. Swift triggers (#251863) on a possible burst
  59. GRB061217: Swift/UVOT refined analysis.
  60. GRB 061217: Magellan Observations
  61. GRB 061217: REM prompt observations
  62. GRB 061217: ROTSE-III Optical Limits
  63. GRB061210: Swift/UVOT observations
  64. GRB 061210: Swift XRT analysis - Possible counterparts
  65. GRB 061214(?): ROTSE-III Optical Limits
  66. GRB 061210: Suzaku WAM observation of the prompt emission
  67. GRB 061210: Gemini/GMOS Observations
  68. GRB 061126: Radio Observations
  69. GRB061210: Radio Observations
  70. GRB 061202: Suzaku WAM observation of the prompt emission
  71. GRB 061210, Swift-BAT refined analysis of the SHB
  72. Optical Afterglow observations of GRB 061126
  73. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  74. GRB 061202: TORTOREM optical upper limits
  75. GRB 061201: VLT optical decay
  76. GRB 061201: SOAR Confirmation of Candidate Afterglow
  77. GRB061202: FRAM early follow-up limit
  78. GRB061202 optical limit by "Pi of the Sky"
  79. Konus-Wind observation of GRB 061201
  80. GRB061202: optical/NIR observations with REM
  81. GRB061202: Swift/UVOT Upper Limits
  82. GRB 061202, Swift-BAT refined analysis
  83. GRB 061202: Swift detection of a burst
  84. GRB 061201: VLT optical observations
  85. INT+WFC observations of GRB 061126
  86. GRB 061126: Early Super-LOTIS Observations
  87. RHESSI Spectrum of GRB061126
  88. GRB061126: Optical afterglow observations from MIRO
  89. GRB061126: Optical afterglow observations from MIRO
  90. GRB 061126 : SDSS Pre-Burst Observations
  91. GRB 061126: Swift/UVOT Observations
  92. GRB 061126: Early Detection of the IR Afterglow
  93. GRB 061126: Swift detection of a burst
  94. GRB 061122: Candidate Optical Afterglow
  95. GRB061122: Swift/UVOT Optical Observations
  96. GRB 061121: ART detection in Ic
  97. GRB061121: P60 Observations
  98. Radio detection of GRB 061121
  99. GRB061122: Swift-XRT position
  100. Konus-Wind observation of GRB 061122

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