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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"

24051 results found.

  1. GRB 021004: Additional V-band Polarimetric Observations
  2. GRB 021004: V-band Polarimetric Observations
  3. GRB 021004: Optical observations at RIKEN
  4. GRB 021004, SPM optical observations
  5. GRB021004: optical observations at Nyrola
  6. GRB021004: Optical Afterglow
  7. GRB 020903: Optical observations at RIKEN
  8. XRF 020903: Supernova
  9. IPN triangulation of GRB020914
  10. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  11. INTEGRAL GRBs added to GCN
  12. GRB020812: optical observation
  13. Second epoch K band imaging of GRB 020819
  14. K band observation of GRB 020819
  15. HETE 2275: Optical observations
  16. Polarimetry of GRB020813: evidence for variability
  17. GRB020812: optical observations
  18. GRB020813: Early Time Magnitude
  19. GRB020813, optical observations
  20. Early Time Limits for GRB020813
  21. GRB 020813 Afterglow Observations; Possible break
  22. GRB 020813 multiband optical observations
  23. GRB020813: optical afterglow
  24. GRB020813: Fading of Candidate OT
  25. GRB020813: Candidate Optical Afterglow
  26. GRB 020812 optical observation
  27. GRB020801, optical afterglow candidate
  28. GRB020625 (=H2081): A Long Burst Localized by HETE
  29. HETE #2081: Optical observations
  30. GRB 020531, simultaneous optical observations
  31. GRB020321 : Optical observations.
  32. GRB 020410, optical observations
  33. GRB 020331: Candidate Optical Afterglow
  34. GRB 020322: BeppoSAX observations of the X-ray afterglow
  35. SN 2002ap - peak brightness date (SN/GRB?)
  36. GRB020321: a faint BeppoSAX detection
  37. GRB020317, optical observations
  38. GRB020305, optical observations
  39. GRB020124, optical observations
  40. HETE 1896: Optical observations
  41. GRB011130 (=XRF011130), Optical Observations
  42. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  43. GRB 011030: K-band observations
  44. The X-ray Flash 011030 ('GRB 011030')
  45. GRB 011019 optical observation
  46. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  47. GRB 010921: The afterglow of HETE #1761
  48. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  49. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  50. GRB010921 Optical Observations
  51. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  52. HETE Trigger #1760 (GRB 010920B?): a new optical source
  53. HETE Trigger #1759 (GRB 010920?) optical observations
  54. BeppoSAX/GRBM detection of GRB 010801
  55. GCN and HETE status
  56. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  57. GRB 010629 Optical Observations
  58. IPN triangulation of GRB010613
  59. IPN triangulation of GRB010612
  60. GRB010518: a faint BeppoSAX detection
  61. GRB010324: BeppoSAX/GRBM data
  62. GRB 010214: X-Ray afterglow
  63. GRB010213, optical observations
  64. GRB010126: CONCAM crude optical limits during GRB
  65. HETE positions added to GCN
  66. CONCAM null result on GRB001005
  67. CONCAM crude optical limits before and after GRB000926
  68. GRB000607, optical observations
  69. GRB 000615: NIR observations
  70. IPN triangulation of GRB000519
  71. RXTE/ASM and IPN localization of GRB 000508B
  72. BeppoSAX GRB000424
  73. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  74. GRB000408, lotis optical observations
  75. GRB 000313 - optical transient in the BATSE error box
  76. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  77. BATSE GRB trigger criterion changed
  78. GRB000210 X-ray afterglow
  79. GRB 000210: BATSE Observations
  80. GRB000201 Optical Observations
  81. GRB 000201: TAROT optical observations
  82. BATSE GRB trigger criteria changed
  83. BATSE+IPN location of GRB000131
  84. BATSE location of GRB000126
  85. BATSE Observations of GRB000115
  86. Second RXTE Observation of GRB 000115
  87. Single IPN error box for GRB991229
  88. GRB 991216: Updated BATSE parameters
  89. GRB 991216--Summary of RXTE Observations
  90. GRB 991216: Extremely bright BATSE burst
  91. GRB991106: BeppoSAX/BATSE results
  92. BeppoSAX NFI Observation of GRB991106
  93. GRB 991105: BATSE Observations
  94. GRB991106, optical observation at SAO-RAS
  95. GRB 991106, LOTIS Optical Observations
  96. GRB991105: SAX-GRBM/-WFC detection
  97. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  98. GRB ALERT: GRB991105
  99. GRB 991014 - BeppoSAX NFI observations
  100. GRB991014 BATSE Observations

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