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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"

21770 results found.

  1. GRB 090301A: Swift-BAT refined analysis
  2. GRB 090301B: Fermi GBM detection
  3. GRB 081211B: Nearby cluster
  4. Ongoing activity of AXP/SGR 1E1547.0-5408
  5. GRB 090217: Suzaku WAM observation of the prompt emission
  6. GRB090217: XRT analysis
  7. Konus-Wind observation of GRB 090217
  8. GRB090217: Fermi-LAT Detection
  9. SGR activity seen by BAT during ICSP Ionospheric Events
  10. Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
  11. VLA radio upper limit on GRB 090205
  12. GRB 090205: Swift/UVOT Upper Limits
  13. GRB 090205: Swift-XRT refined analysis
  14. GRB 090205: GROND observations and photometric redshift estimate
  15. GRB 090205: VLT candidate afterglow
  16. GRB 090205: Swift-BAT refined analysis
  17. GRB 090205: Enhanced Swift-XRT position
  18. GRB 090205: Swift detection of a burst
  19. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  20. GRB 090131: Suzaku WAM observation of the prompt emission
  21. Konus-Wind observation of GRB 090201
  22. GRB090201: Swift UVOT upper limits
  23. GRB 090201: object inside the enhanced XRT error circle
  24. GRB 090201: Enhanced Swift-XRT position
  25. GRB 090201: VLT NIR observations
  26. GRB 090201: Swift-BAT refined analysis
  27. GRB 090201: VLT afterglow candidate
  28. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  29. GRB090113: MAGIC telescope GeV observation
  30. GRB 090201: ROTSE-III Optical Limits
  31. GRB 090126A: Swift/UVOT Upper Limits
  32. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  33. Suzaku ToO Observation of AXP 1E 1547.0-5408
  34. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  35. GRB 090102: HST observations and host galaxy
  36. GRB 090118: no afterglow candidate
  37. GRB 090123: GROND detection
  38. GRB 090123: Swift/UVOT Observations
  39. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  40. GRB090123: Enhanced Swift-XRT position
  41. GRB 090123: Swift detection of a burst
  42. AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
  43. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  44. AXP 1E1547.0-5408: INTEGRAL SPI-ACS confirms activity increase
  45. GRB 090117C: Suzaku WAM observation of the prompt emission
  46. Trigger 340734: Swift detection of a possible short burst
  47. GRB 090118: Subaru NIR Observation
  48. GRB 090118: KPNO 4m 2nd Epoch Observations
  49. GRB 090118 (BATSS): GRT Optical Observation
  50. GRB 090118: KPNO 4m Detection of Candidate Afterglow
  51. GRB090118 Swift/UVOT upper limits
  52. GRB 090118: GROND Upper Limits
  53. GRB 090118: Possible burst detection from Swift-BAT slew data
  54. GRB 090117C - Fermi GRB Detection
  55. GRB 090117 - Fermi GBM Observations
  56. GRB 090117: GROND Upper Limits
  57. GRB090117 Swift/UVOT upper limits
  58. GRB090117: Swift-XRT detection of a possible candidate afterglow
  59. GRB090102: MAGIC telescope GeV observation
  60. GRB 090112B: Suzaku WAM observation of the prompt emission
  61. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  62. GRB 090113: Swift UVOT upper limits
  63. GRB 090113: GROND Upper Limits
  64. GRB 090113: Observations from NOT
  65. GRB 090113: Enhanced Swift-XRT position
  66. GRB 090113: ROTSE-III Optical Limits
  67. GRB 090113: Swift detection of a burst
  68. GRB 090109: Fermi GBM detection
  69. GRB 090111: Swift UVOT Upper Limits
  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. GRB 090107B: Swift XRT afterglow confirmation
  74. GRB 090107B: Swift/UVOT Observations
  75. GRB 090107B: Swift-XRT detection of possible afterglow
  76. GRB 090107B: ROTSE-III Optical Limits
  77. VLA radio upper limit on GRB 090102
  78. GRB 090102: GRT Optical Observation
  79. Swift triggered on the HMXB 1A 1118-61
  80. Konus-Wind observation of GRB 090102
  81. GRB 090102: Hobby-Eberly Telescope Spectroscopy
  82. GRB 090102: P60 Imaging and P200 Spectroscopy
  83. GRB 090102 Observations from IAC80
  84. GRB 090102: GROND observations of the optical afterglow
  85. GRB 090102: NOT redshift
  86. GRB 090102: Enhanced Swift-XRT position
  87. GRB 090102: REM observations of a bright afterglow
  88. GRB 090102: Swift detection of a burst with an optical counterpart
  89. GRB 090102: TAROT Calern observatory optical observations
  90. GRB 081230: GROND confirmation of the afterglow
  91. GRB 081230, Swift-BAT refined analysis
  92. GRB081230: Swift-XRT refined analysis
  93. GRB 081230 Swift/UVOT Observations
  94. GRB 081230: Enhanced Swift-XRT position
  95. GRB 081230: Swift detection of a burst
  96. GRB 081228, Swift-BAT refined analysis
  97. VLA radio detection of GRB 081221
  98. GRB 081228: Swift/UVOT Upper Limits
  99. GRB 081228: Swift-XRT Team refined analysis
  100. GRB 081228: detection by GROND

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