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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"

4183 results found.

  1. IPN Triangulation of bright GRB 090720B
  2. GRB 090713: Fermi GBM detection
  3. GRB 090529: CrAO optical upper limit
  4. GRB 090529: MTM-500 optical observations
  5. Konus-Wind observation of GRB 090626
  6. GRB090618: HCT optical observations
  7. PAIRITEL observations of GRB 090618
  8. GRB 090618: OA behavior from KAIT
  9. GRB 090618: Swift detection of a bright burst with optical afterglow
  10. SGR 0418+5729 Fermi/GBM Detection of Pulsations
  11. RXTE Discovery of Pulsations from SGR 0418+5729
  12. Konus-RF observation of SGR burst 090605A
  13. Discovery of a new soft gamma repeater source, SGR 0418+5729
  14. GRB090529B: ROVOR Upper Limits
  15. GRB 090529C: Fermi GBM detection
  16. GRB 090529B: Fermi GBM detection
  17. GRB 090529: MITSuME optical observation
  18. GRB 090530: GRT Optical Observation
  19. GRB 090531: GROND upper limits
  20. GRB 090528B: Fermi GBM detection
  21. GRB 090529: optical observations
  22. GRB 090529: Xinglong TNT optical observation
  23. GRB 090519: NOT afterglow candidate
  24. GRB 090509, further Swift-BAT refined analysis
  25. GRB 090509: Swift-BAT refined analysis
  26. GRB 090323: optical observations
  27. GRB 090427: GROND observations
  28. Refined analysis of ICSP VLF observation of SGR J1550-5418 bursts on 22nd January, 2009
  29. GRB 090429D: Fermi GBM detection
  30. GRB 090429C: Fermi GBM detection
  31. GRB 090429B: RIMOTS optical upper limits
  32. GRB 090424 : Multiband Optical observation from Nainital
  33. IPN triangulation of very bright GRB 090427
  34. GRB 090426, RIMOTS optical upper limits
  35. GRB 090424: Liverpool Telescope observations
  36. GRB 090422: Fermi GBM observation
  37. GRB 090418B: Suzaku WAM observation of the prompt emission
  38. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  39. GRB 090417B: MITSuME Okayama optical upper limits
  40. GRB090417B: Xinglong TNT optical upper limit
  41. GRB 090417A: Early-type nature of the putative host
  42. GRB 090417A: nearby galaxy redshift
  43. GRB 090408b: IPN Triangulation
  44. GRB 090328b: IPN Triangulation
  45. GRB 090407: ROTSE-III Optical Limits
  46. GRB 090407: Swift detection of a burst
  47. GRB 090404: Swift detection of a burst
  48. GRB 090328: BOOTES-3 optical observations
  49. GRB 090328: Gemini South Redshift
  50. SGR J1550-5418: two Fermi GBM triggers on March 22
  51. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  52. GRB 090313: Ongoing plateau phase
  53. GRB 090205: Zadko Telescope late-time observations
  54. GRB 090309: Swift detection of a burst
  55. ATCA observation of SGR J1550-5418
  56. GRB 090306B: Burst detection from Swift-BAT slew data
  57. GRB 090303: Fermi GBM detection
  58. Konus-RF catches first GRB and SGR bursts
  59. SGR J1550-5418
  60. Ongoing activity of AXP/SGR 1E1547.0-5408
  61. GRB 090217: Fermi GBM detection
  62. SGR activity seen by BAT during ICSP Ionospheric Events
  63. Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
  64. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  65. GRB 090129: Fermi GBM detection
  66. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  67. GRB 090201: ROTSE-III Optical Limits
  68. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  69. Suzaku ToO Observation of AXP 1E 1547.0-5408
  70. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  71. AXP 1E1547.0-5408: RHESSI observations up to 400 keV
  72. Konus-Wind detection of very bright SGR-like burst on January 25, 2009
  73. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  74. Trigger 340734: Swift detection of a possible short burst
  75. AXP 1E1547.0-5408 activity with SGR bursts
  76. GRB 090117C - Fermi GRB Detection
  77. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  78. GRB 090108: Fermi GBM Detection
  79. GRB 081231: Fermi GBM Detection
  80. GRB 081229: Fermi GBM detection
  81. GRB 090102: Swift detection of a burst with an optical counterpart
  82. GRB 081230: GROND confirmation of the afterglow
  83. GRB 081230 Swift/UVOT Observations
  84. GRB 081230: Swift/UVOT Detection of an Optical Afterglow
  85. GRB 081230: ROTSE-III Detection of Optical Counterpart
  86. GRB 081230: Swift detection of a burst
  87. Konus-Wind observation of GRB 081222
  88. Swift/UVOT observations of GRB 081221
  89. GRB 081222: GROND Detection of the Optical/NIR Afterglow
  90. Fermi Trig Num 251059717 = SGR 0044+42: MASTER prompt optical observations
  91. GRB 081203A: optical observations
  92. GRB 081206B: Fermi GBM detection
  93. GRB 081206: Fermi GBM detection
  94. GRB081203A: MITSuME optical observation
  95. GRB 081203A: Optical observations of Xinglong TNT telescope
  96. GRB 081204: Swift XRT afterglow candidate
  97. GRB081203A: optical observation
  98. GRB081203: optical observation
  99. GRB 081203: Swift detection of a burst with a bright optical counterpart
  100. Swift Trigger 335971: Swift/UVOT Observations

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