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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

3115 results found.

  1. GRB 090323: Swift-XRT refined analysis
  2. GRB 090313 - PAIRITEL NIR detections
  3. IPN localization of short GRB 090305C
  4. Konus-Wind observation of bright short GRB 090227B
  5. IPN localization of short bright GRB 090227B
  6. VLA radio upper limit on GRB 090205
  7. Konus-Wind observation of GRB 090201
  8. GRB 090201: Swift-XRT refined analysis
  9. GRB 090201: Swift detection of a burst
  10. GRB 090129: Swift-BAT refined analysis
  11. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  12. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  13. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  14. GRB 081230: ROTSE-III Detection of Optical Counterpart
  15. Konus-Wind observation of GRB 081222
  16. GRB 081217: Fermi GBM detection
  17. GRB 081210: Xinglong TNT R band Upper Limits
  18. IPN triangulation of short hard GRB 081209
  19. GRB 081203A: optical observations
  20. Swift-XRT observations of GRB 081203B
  21. Swift-BAT Trigger 334129: possible burst
  22. SGR 1806-20: Fermi GBM detection
  23. GRB 081024: Swift detection of a burst
  24. GRB 081017, Swift-BAT refined analysis
  25. GRB 081016B: ROTSE-III Optical Limits
  26. GRB 081016B: Swift detection of a burst
  27. Swift detection of flare on CC Eri
  28. Detection of flare star Algol in Swift-BAT slew data
  29. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  30. GRB 080928: Swift-XRT refined analysis
  31. GRB 080916B: Swift detection of a burst
  32. GRB 080903: optical observations
  33. GRB 080903: Liverpool Telescope observations
  34. GRB 080903: Astrotel-Caucasus optical observations
  35. GRB 080903: Optical afterglow candidate
  36. SGR 0501+4516: Decline in Activity
  37. Konus-Wind observations of new SGR 0501+4516
  38. INTEGRAL ToO Observation of SGR0501+4516
  39. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  40. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  41. GRB080810: optical observations
  42. GRB 080810: Swift/UVOT Refined Analysis
  43. GRB 080810: Liverpool Telescope observations
  44. GRB 080810: D50 optical observation
  45. GRB 080810: Observations from NOT
  46. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  47. GRB 080810: Keck/HIRES Spectroscopy
  48. GRB 080810: Swift detection of a burst with a bright optical afterglow
  49. GRB 080723B: XMM-Newton observation
  50. GRB 080727B: IR photometry
  51. GRB 080723B - Swift-XRT position
  52. GRB 080710: REM afterglow confirmation & brightening
  53. GRB 080707: VLT redshift
  54. GRB 080703: UVOT Follow-Up Observation
  55. GRB 080703: VLT observations of the afterglow
  56. GRB 080703: Swift detection of a burst with optical afterglow
  57. GRB 080703A: ROTSE-III Detection of Optical Counterpart
  58. GRB 080623: Swift XRT prompt analysis
  59. GRB 080613B: GROND Upper Limits
  60. GRB 080605: MASTER VWF 46 s AT observation
  61. GRB 080605: Swift detection of a burst with an optical afterglow
  62. Swift/UVOT observations of GRB080604
  63. GRB 080604: Early Super-LOTIS Observations
  64. GRB080604: confirmation of optical afterglow
  65. GRB 080604: Swift detection of a burst with an optical afterglow
  66. Konus-Wind observation of reactivation of SGR 1627-41
  67. Reactivation of SGR 1627-41
  68. IPN triangulation of bright GRB 080513
  69. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  70. GRB 080503: Late-time Optical rebrightening (possible mini-SN)
  71. GRB 080503: Enhanced Swift-XRT position
  72. GRB 080503: New candidate afterglow/host in Gemini imaging
  73. GRB 080503: Swift detection of a short burst
  74. Swift-BAT trigger 309665 is not a GRB
  75. GRB 080420?: Swift detection of a possible short burst
  76. GRB 080413A, Swift-BAT refined analysis
  77. GRB080330: MAGIC telescope GeV observation
  78. GRB 080405: Swift-BAT refined analysis
  79. GRB 080328: Swift detection of a burst with an optical counterpart
  80. GRB 080320: Early Super-LOTIS Observations
  81. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  82. GRB 080319b light curve by Pi-of-the-Sky
  83. GRB 080319b prompt optical observation by Pi-of-the-Sky
  84. GRB080310: Optical observation by MITSuME telescope
  85. GRB080307: Optical upper limits
  86. GRB 080218B: Swift detection of a burst
  87. GRB080212: Optical afterglow candidate observed by MITSuME Telescope
  88. GRB 080205: Swift/UVOT observations
  89. GRB 080205: Enhanced Swift-XRT position
  90. GRB 080205: KAIT OA detection
  91. GRB 080205: Swift detection of a burst
  92. GRB 080129: GROND detection in all bands, and fading
  93. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  94. IPN triangulation of GRB080122
  95. GRB 080121: Nearby SDSS galaxies
  96. GRB 080120: Swift-XRT refined analysis
  97. GRB080120: Swift XRT position
  98. GRB 071227: Swift detection of a burst
  99. GRB071020: optical observations
  100. GRB 071122 Swift-XRT refined analysis

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