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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"

3873 results found.

  1. RXTE Discovery of Pulsations from SGR 0418+5729
  2. Konus-RF observation of SGR burst 090605A
  3. Discovery of a new soft gamma repeater source, SGR 0418+5729
  4. GRB090529B: ROVOR Upper Limits
  5. GRB 090529C: Fermi GBM detection
  6. GRB 090529B: Fermi GBM detection
  7. GRB 090529: MITSuME optical observation
  8. GRB 090530: GRT Optical Observation
  9. GRB 090531: GROND upper limits
  10. GRB 090528B: Fermi GBM detection
  11. GRB 090529: optical observations
  12. GRB 090529: Xinglong TNT optical observation
  13. GRB 090519: NOT afterglow candidate
  14. GRB 090509, further Swift-BAT refined analysis
  15. GRB 090509: Swift-BAT refined analysis
  16. GRB 090323: optical observations
  17. GRB 090427: GROND observations
  18. Refined analysis of ICSP VLF observation of SGR J1550-5418 bursts on 22nd January, 2009
  19. GRB 090429D: Fermi GBM detection
  20. GRB 090429C: Fermi GBM detection
  21. GRB 090429B: RIMOTS optical upper limits
  22. GRB 090424 : Multiband Optical observation from Nainital
  23. IPN triangulation of very bright GRB 090427
  24. GRB 090426, RIMOTS optical upper limits
  25. GRB 090424: Liverpool Telescope observations
  26. GRB 090422: Fermi GBM observation
  27. GRB 090418B: Suzaku WAM observation of the prompt emission
  28. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  29. GRB 090417B: MITSuME Okayama optical upper limits
  30. GRB090417B: Xinglong TNT optical upper limit
  31. GRB 090417A: Early-type nature of the putative host
  32. GRB 090417A: nearby galaxy redshift
  33. GRB 090408b: IPN Triangulation
  34. GRB 090328b: IPN Triangulation
  35. GRB 090407: ROTSE-III Optical Limits
  36. GRB 090407: Swift detection of a burst
  37. GRB 090404: Swift detection of a burst
  38. GRB 090328: BOOTES-3 optical observations
  39. GRB 090328: Gemini South Redshift
  40. SGR J1550-5418: two Fermi GBM triggers on March 22
  41. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  42. GRB 090313: Ongoing plateau phase
  43. GRB 090205: Zadko Telescope late-time observations
  44. GRB 090309: Swift detection of a burst
  45. ATCA observation of SGR J1550-5418
  46. GRB 090306B: Burst detection from Swift-BAT slew data
  47. GRB 090303: Fermi GBM detection
  48. Konus-RF catches first GRB and SGR bursts
  49. SGR J1550-5418
  50. Ongoing activity of AXP/SGR 1E1547.0-5408
  51. GRB 090217: Fermi GBM detection
  52. SGR activity seen by BAT during ICSP Ionospheric Events
  53. Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
  54. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  55. GRB 090129: Fermi GBM detection
  56. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  57. GRB 090201: ROTSE-III Optical Limits
  58. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  59. Suzaku ToO Observation of AXP 1E 1547.0-5408
  60. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  61. AXP 1E1547.0-5408: RHESSI observations up to 400 keV
  62. Konus-Wind detection of very bright SGR-like burst on January 25, 2009
  63. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  64. Trigger 340734: Swift detection of a possible short burst
  65. AXP 1E1547.0-5408 activity with SGR bursts
  66. GRB 090117C - Fermi GRB Detection
  67. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  68. GRB 090108: Fermi GBM Detection
  69. GRB 081231: Fermi GBM Detection
  70. GRB 081229: Fermi GBM detection
  71. GRB 090102: Swift detection of a burst with an optical counterpart
  72. GRB 081230: GROND confirmation of the afterglow
  73. GRB 081230 Swift/UVOT Observations
  74. GRB 081230: Swift/UVOT Detection of an Optical Afterglow
  75. GRB 081230: ROTSE-III Detection of Optical Counterpart
  76. GRB 081230: Swift detection of a burst
  77. Konus-Wind observation of GRB 081222
  78. Swift/UVOT observations of GRB 081221
  79. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  80. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  81. GRB 081203A: optical observations
  82. GRB 081206B: Fermi GBM detection
  83. GRB 081206: Fermi GBM detection
  84. GRB081203A: MITSuME optical observation
  85. GRB 081203A: Optical observations of Xinglong TNT telescope
  86. GRB 081204: Swift XRT afterglow candidate
  87. GRB081203A: optical observation
  88. GRB081203: optical observation
  89. GRB 081203: Swift detection of a burst with a bright optical counterpart
  90. Swift Trigger 335971: Swift/UVOT Observations
  91. GRB 081129: Fermi GBM detection
  92. SGR 1806-20: Fermi GBM detection.
  93. GRB 081126: Swift observations continuing
  94. GRB 081119: Fermi GBM detection
  95. SGR 1806-20: Fermi GBM detection
  96. GRB 081104: GROND found no Optical/NIR Afterglow
  97. SGR 0501+4516: optical observations in August
  98. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  99. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  100. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis

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