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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"

2722 results found.

  1. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  2. GRB 090417B: Swift-XRT refined analysis
  3. GRB 090411B: Suzaku WAM observation of the prompt emission
  4. GRB 090411B: Fermi GBM detection
  5. Swift-BAT trigger 348781: almost certainly not a burst
  6. GRB 090403: Fermi GBM detection
  7. GRB090401B, RIMOTS optical upper limits
  8. GRB 090401B: Swift detection of a burst
  9. GRB 090324: Suzaku WAM observation of the prompt emission
  10. GRB 090323: Swift-XRT refined analysis
  11. GRB 090313 - PAIRITEL NIR detections
  12. IPN localization of short GRB 090305C
  13. Konus-Wind observation of bright short GRB 090227B
  14. IPN localization of short bright GRB 090227B
  15. VLA radio upper limit on GRB 090205
  16. Konus-Wind observation of GRB 090201
  17. GRB 090201: Swift-XRT refined analysis
  18. GRB 090201: Swift detection of a burst
  19. GRB 090129: Swift-BAT refined analysis
  20. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  21. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  22. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  23. GRB 081230: ROTSE-III Detection of Optical Counterpart
  24. Konus-Wind observation of GRB 081222
  25. GRB 081217: Fermi GBM detection
  26. GRB 081210: Xinglong TNT R band Upper Limits
  27. IPN triangulation of short hard GRB 081209
  28. GRB 081203A: optical observations
  29. Swift-XRT observations of GRB 081203B
  30. Swift-BAT Trigger 334129: possible burst
  31. SGR 1806-20: Fermi GBM detection
  32. GRB 081024: Swift detection of a burst
  33. GRB 081017, Swift-BAT refined analysis
  34. GRB 081016B: ROTSE-III Optical Limits
  35. GRB 081016B: Swift detection of a burst
  36. Swift detection of flare on CC Eri
  37. Detection of flare star Algol in Swift-BAT slew data
  38. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  39. GRB 080928: Swift-XRT refined analysis
  40. GRB 080916B: Swift detection of a burst
  41. GRB 080903: optical observations
  42. GRB 080903: Liverpool Telescope observations
  43. GRB 080903: Astrotel-Caucasus optical observations
  44. GRB 080903: Optical afterglow candidate
  45. SGR 0501+4516: Decline in Activity
  46. Konus-Wind observations of new SGR 0501+4516
  47. INTEGRAL ToO Observation of SGR0501+4516
  48. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  49. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  50. GRB080810: optical observations
  51. GRB 080810: Swift/UVOT Refined Analysis
  52. GRB 080810: Liverpool Telescope observations
  53. GRB 080810: D50 optical observation
  54. GRB 080810: Observations from NOT
  55. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  56. GRB 080810: Keck/HIRES Spectroscopy
  57. GRB 080810: Swift detection of a burst with a bright optical afterglow
  58. GRB 080723B: XMM-Newton observation
  59. GRB 080727B: IR photometry
  60. GRB 080723B - Swift-XRT position
  61. GRB 080710: REM afterglow confirmation & brightening
  62. GRB 080707: VLT redshift
  63. GRB 080703: UVOT Follow-Up Observation
  64. GRB 080703: VLT observations of the afterglow
  65. GRB 080703: Swift detection of a burst with optical afterglow
  66. GRB 080703A: ROTSE-III Detection of Optical Counterpart
  67. GRB 080623: Swift XRT prompt analysis
  68. GRB 080613B: GROND Upper Limits
  69. GRB 080605: MASTER VWF 46 s AT observation
  70. GRB 080605: Swift detection of a burst with an optical afterglow
  71. Swift/UVOT observations of GRB080604
  72. GRB 080604: Early Super-LOTIS Observations
  73. GRB080604: confirmation of optical afterglow
  74. GRB 080604: Swift detection of a burst with an optical afterglow
  75. Konus-Wind observation of reactivation of SGR 1627-41
  76. Reactivation of SGR 1627-41
  77. IPN triangulation of bright GRB 080513
  78. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  79. GRB 080503: Late-time Optical rebrightening (possible mini-SN)
  80. GRB 080503: Enhanced Swift-XRT position
  81. GRB 080503: New candidate afterglow/host in Gemini imaging
  82. GRB 080503: Swift detection of a short burst
  83. Swift-BAT trigger 309665 is not a GRB
  84. GRB 080420?: Swift detection of a possible short burst
  85. GRB 080413A, Swift-BAT refined analysis
  86. GRB080330: MAGIC telescope GeV observation
  87. GRB 080405: Swift-BAT refined analysis
  88. GRB 080328: Swift detection of a burst with an optical counterpart
  89. GRB 080320: Early Super-LOTIS Observations
  90. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  91. GRB 080319b light curve by Pi-of-the-Sky
  92. GRB 080319b prompt optical observation by Pi-of-the-Sky
  93. GRB080310: Optical observation by MITSuME telescope
  94. GRB080307: Optical upper limits
  95. GRB 080218B: Swift detection of a burst
  96. GRB080212: Optical afterglow candidate observed by MITSuME Telescope
  97. GRB 080205: Swift/UVOT observations
  98. GRB 080205: Enhanced Swift-XRT position
  99. GRB 080205: KAIT OA detection
  100. GRB 080205: Swift detection of a burst

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