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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"

2730 results found.

  1. GRB 090510B: Fermi GBM detection
  2. GRB 090426: optical observations
  3. GRB 090426: R-band limit
  4. GRB 090426: Swift detection of a burst with an optical counterpart
  5. GRB 090424: Liverpool Telescope observations
  6. GRB 090423 limiting magnitudes
  7. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  8. GRB 090417B: Swift-XRT refined analysis
  9. GRB 090411B: Suzaku WAM observation of the prompt emission
  10. GRB 090411B: Fermi GBM detection
  11. Swift-BAT trigger 348781: almost certainly not a burst
  12. GRB 090403: Fermi GBM detection
  13. GRB090401B, RIMOTS optical upper limits
  14. GRB 090401B: Swift detection of a burst
  15. GRB 090324: Suzaku WAM observation of the prompt emission
  16. GRB 090323: Swift-XRT refined analysis
  17. GRB 090313 - PAIRITEL NIR detections
  18. IPN localization of short GRB 090305C
  19. Konus-Wind observation of bright short GRB 090227B
  20. IPN localization of short bright GRB 090227B
  21. VLA radio upper limit on GRB 090205
  22. Konus-Wind observation of GRB 090201
  23. GRB 090201: Swift-XRT refined analysis
  24. GRB 090201: Swift detection of a burst
  25. GRB 090129: Swift-BAT refined analysis
  26. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  27. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  28. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  29. GRB 081230: ROTSE-III Detection of Optical Counterpart
  30. Konus-Wind observation of GRB 081222
  31. GRB 081217: Fermi GBM detection
  32. GRB 081210: Xinglong TNT R band Upper Limits
  33. IPN triangulation of short hard GRB 081209
  34. GRB 081203A: optical observations
  35. Swift-XRT observations of GRB 081203B
  36. Swift-BAT Trigger 334129: possible burst
  37. SGR 1806-20: Fermi GBM detection
  38. GRB 081024: Swift detection of a burst
  39. GRB 081017, Swift-BAT refined analysis
  40. GRB 081016B: ROTSE-III Optical Limits
  41. GRB 081016B: Swift detection of a burst
  42. Swift detection of flare on CC Eri
  43. Detection of flare star Algol in Swift-BAT slew data
  44. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  45. GRB 080928: Swift-XRT refined analysis
  46. GRB 080916B: Swift detection of a burst
  47. GRB 080903: optical observations
  48. GRB 080903: Liverpool Telescope observations
  49. GRB 080903: Astrotel-Caucasus optical observations
  50. GRB 080903: Optical afterglow candidate
  51. SGR 0501+4516: Decline in Activity
  52. Konus-Wind observations of new SGR 0501+4516
  53. INTEGRAL ToO Observation of SGR0501+4516
  54. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  55. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  56. GRB080810: optical observations
  57. GRB 080810: Swift/UVOT Refined Analysis
  58. GRB 080810: Liverpool Telescope observations
  59. GRB 080810: D50 optical observation
  60. GRB 080810: Observations from NOT
  61. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  62. GRB 080810: Keck/HIRES Spectroscopy
  63. GRB 080810: Swift detection of a burst with a bright optical afterglow
  64. GRB 080723B: XMM-Newton observation
  65. GRB 080727B: IR photometry
  66. GRB 080723B - Swift-XRT position
  67. GRB 080710: REM afterglow confirmation & brightening
  68. GRB 080707: VLT redshift
  69. GRB 080703: UVOT Follow-Up Observation
  70. GRB 080703: VLT observations of the afterglow
  71. GRB 080703: Swift detection of a burst with optical afterglow
  72. GRB 080703A: ROTSE-III Detection of Optical Counterpart
  73. GRB 080623: Swift XRT prompt analysis
  74. GRB 080613B: GROND Upper Limits
  75. GRB 080605: MASTER VWF 46 s AT observation
  76. GRB 080605: Swift detection of a burst with an optical afterglow
  77. Swift/UVOT observations of GRB080604
  78. GRB 080604: Early Super-LOTIS Observations
  79. GRB080604: confirmation of optical afterglow
  80. GRB 080604: Swift detection of a burst with an optical afterglow
  81. Konus-Wind observation of reactivation of SGR 1627-41
  82. Reactivation of SGR 1627-41
  83. IPN triangulation of bright GRB 080513
  84. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  85. GRB 080503: Late-time Optical rebrightening (possible mini-SN)
  86. GRB 080503: Enhanced Swift-XRT position
  87. GRB 080503: New candidate afterglow/host in Gemini imaging
  88. GRB 080503: Swift detection of a short burst
  89. Swift-BAT trigger 309665 is not a GRB
  90. GRB 080420?: Swift detection of a possible short burst
  91. GRB 080413A, Swift-BAT refined analysis
  92. GRB080330: MAGIC telescope GeV observation
  93. GRB 080405: Swift-BAT refined analysis
  94. GRB 080328: Swift detection of a burst with an optical counterpart
  95. GRB 080320: Early Super-LOTIS Observations
  96. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  97. GRB 080319b light curve by Pi-of-the-Sky
  98. GRB 080319b prompt optical observation by Pi-of-the-Sky
  99. GRB080310: Optical observation by MITSuME telescope
  100. GRB080307: Optical upper limits

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