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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"

28054 results found.

  1. GRB 090202: Fermi GBM detection
  2. GRB 090131: Fermi GBM detection
  3. GRB 090201: Swift-XRT refined analysis
  4. GRB090201: Swift UVOT upper limits
  5. GRB 090201: object inside the enhanced XRT error circle
  6. GRB 090201: Enhanced Swift-XRT position
  7. GRB 090201: VLT NIR observations
  8. GRB 090201: Swift-BAT refined analysis
  9. GRB 090201: VLT afterglow candidate
  10. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  11. GRB090113: MAGIC telescope GeV observation
  12. GRB 090201: ROTSE-III Optical Limits
  13. GRB 090126A: Swift/UVOT Upper Limits
  14. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  15. GRB 090129: Swift-BAT refined analysis
  16. GRB 090129: Swift detection of a burst
  17. Suzaku ToO Observation of AXP 1E 1547.0-5408
  18. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  19. GRB 090102: HST observations and host galaxy
  20. GRB 090126C: Fermi GBM detection
  21. GRB 090126A: Swift-XRT Refined Analysis
  22. GRB 090126B: Fermi GBM detection
  23. GRB 090126: SuperAGILE Localization of a Long GRB
  24. GRB 090118: no afterglow candidate
  25. GRB 090123: GROND detection
  26. 1E1547.0-5408: Swift detection of dust halo
  27. GRB 090123: Swift XRT refined analysis
  28. GRB 090123: Swift/UVOT Observations
  29. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  30. GRB 090123: Swift-BAT refined analysis
  31. GRB090123: Enhanced Swift-XRT position
  32. GRB 090123: Swift detection of a burst
  33. AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
  34. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  35. GRB 090117C: Suzaku WAM observation of the prompt emission
  36. Trigger 340734: Swift detection of a possible short burst
  37. GRB 090118: Subaru NIR Observation
  38. GRB 090118: KPNO 4m 2nd Epoch Observations
  39. GRB 090118 (BATSS): GRT Optical Observation
  40. GRB 090118: KPNO 4m Detection of Candidate Afterglow
  41. GRB 090118: Swift-XRT observations
  42. GRB090118 Swift/UVOT upper limits
  43. GRB 090118: GROND Upper Limits
  44. GRB 090118: Possible burst detection from Swift-BAT slew data
  45. GRB 090117B : Fermi GBM detection
  46. GRB 090117C - Fermi GRB Detection
  47. GRB 090117 - Fermi GBM Observations
  48. GRB 090117: GROND Upper Limits
  49. GRB090117 Swift/UVOT upper limits
  50. GRB090117: Swift-XRT detection of a possible candidate afterglow
  51. GRB 090117 - SuperAGILE Localization of a long GRB
  52. GRB 090112B: Suzaku WAM observation of the prompt emission
  53. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  54. GRB 090113: Swift UVOT upper limits
  55. GRB 090113: GROND Upper Limits
  56. GRB 090113: Swift-XRT refined analysis
  57. GRB 090113: Observations from NOT
  58. GRB 090113: Enhanced Swift-XRT position
  59. GRB 090113: Swift-BAT refined analysis
  60. GRB 090113: ROTSE-III Optical Limits
  61. GRB 090112B: Fermi GBM Detection
  62. GRB 090113: Swift detection of a burst
  63. GRB 090112: Fermi GBM detection
  64. GRB 090109: Fermi GBM detection
  65. GRB 090108B: Fermi GBM detection
  66. GRB 090111, Swift-BAT refined analysis
  67. GRB 090111: Swift UVOT Upper Limits
  68. GRB 090108: Fermi GBM Detection
  69. GRB 090111: Swift-XRT refined analysis
  70. GRB 090111: Enhanced Swift-XRT position
  71. GRB 090111: Swift detection of a burst
  72. GRB 090107B: Suzaku WAM observation of the prompt emission
  73. GRB090107B: Fermi GBM Detection
  74. GRB 090107B: Swift XRT afterglow confirmation
  75. GRB 090107B: Swift/UVOT Observations
  76. GRB 090107B: Swift-XRT detection of possible afterglow
  77. GRB 090107B: a long GRB localized by INTEGRAL
  78. Fermi/GBM detection of GRB 081226A
  79. Fermi/GBM detection of GRB 081225
  80. GRB 090107: Swift-BAT refined analysis
  81. GRB 081231: Fermi GBM Detection
  82. VLA radio upper limit on GRB 090102
  83. GRB 090102: GRT Optical Observation
  84. Swift triggered on the HMXB 1A 1118-61
  85. GRB 081229: Fermi GBM detection
  86. GRB 090102: P60 Imaging and P200 Spectroscopy
  87. GRB 090102 Observations from IAC80
  88. GRB 090102: GROND observations of the optical afterglow
  89. GRB 090102: Swift-BAT refined analysis
  90. GRB 090102: Swift XRT refined analysis
  91. GRB 090102: NOT redshift
  92. GRB 090102: Enhanced Swift-XRT position
  93. GRB 090102: REM observations of a bright afterglow
  94. GRB 090102: Swift detection of a burst with an optical counterpart
  95. GRB 090102: TAROT Calern observatory optical observations
  96. GRB 081230: GROND confirmation of the afterglow
  97. GRB 081230, Swift-BAT refined analysis
  98. GRB081230: Swift-XRT refined analysis
  99. GRB 081230 Swift/UVOT Observations
  100. GRB 081230: Enhanced Swift-XRT position

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