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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"

26347 results found.

  1. BeppoSAX/GRBM detection of GRB010728
  2. GRB 010222 - WHT BVRI images
  3. SGR1900+14 burst seen by HETE: BeppoSAX data
  4. GRB 010629 Optical Observations
  5. GRB010629: Optical Observations
  6. SGR1900+14: High Fluence Burst Localized by HETE
  7. IPN triangulation of GRB010629
  8. GRB010629: A Burst Localized by HETE
  9. SGR1900+14: Second Burst Localized by HETE
  10. SGR1900+14: A Burst Localized by HETE
  11. SGR1806-20: A Second, Intense Burst Localized by HETE
  12. SGR1806-20: Localization by HETE
  13. IPN triangulation of GRB010613
  14. IPN triangulation of GRB010612
  15. IPN triangulation of GRB010612
  16. HETE Fully-Automated GCN Notices
  17. GRB000301C: Late-time HST/STIS observation
  18. GRB010518: a faint BeppoSAX detection
  19. GRB000418: HST/STIS Second-epoch Observations
  20. GRB010427, Gamma Ray Observations
  21. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  22. Millimeter observation of SGR 1900+14
  23. Chandra Observations of SGR 1900+14
  24. SGR 1900+14, Chandra observations
  25. SGR1900+14, I-band observations
  26. IPN Triangulation of the Giant Flare from SGR1900+14
  27. Giant flare from SGR1900+14
  28. GRB010412: BeppoSAX GRBM and WFC observations
  29. IPN Triangulation of GRB010412
  30. BeppoSAX GRB ALERT: GRB010412
  31. GRB Observation Report
  32. REVISED LOCATION OF GRB010326A
  33. GRB 980326: Late-time HST/STIS observations
  34. GRB010324, field photometry
  35. Further Optical Observations of GRB 010324
  36. GRB010222, CXO X-ray observations
  37. GRB 010326B: Optical observations
  38. GRB010326B: Localization by HETE (2nd GRB for this date)
  39. GRB010326: Refined Localization by HETE
  40. GRB010326: Localization by HETE
  41. Duration, ECT, peak flux and fluence of GRB010324
  42. IPN TRIANGULATION OF GRB010324
  43. GRB990705, VLT-FORS1 observations of the host galaxy
  44. Support extension to the BeppoSAX mission
  45. GRB 010222 - HEGRA GeV/TeV Observations
  46. GRB010222 - Optical observation
  47. GRB 010222, Optical Observations
  48. GRB010220 optical obsercations
  49. GRB 010222: High-Resolution Keck Spectroscopy
  50. GRB 010214, I-band data
  51. Sub-millimeter Excess/GRB 010222
  52. GRB 010222
  53. GRB 010222
  54. GRB010222 further R-band photometry
  55. GRB010222: R-band data
  56. GRB010222 Optical observations
  57. GRB 010222: Keck Spectroscopy
  58. GRB010222 further R-band photometry
  59. GRB010222, possible increase of optical decay slope
  60. GRB 010222 Kyoto optical observation
  61. GRB010222: fading behavior
  62. GRB010222 R-BAND OBSERVATION
  63. GRB 010220: Near-IR Observations
  64. GRB010214 follow-up from Hanle
  65. GRB 010222: Near-IR Observations
  66. GRB 010222, Decay Slope Confirmed
  67. GRB 010214, Optical Observations
  68. GRB010222: Optical Observations
  69. GRB010222, radio observations
  70. GRB010214B,Gamma Ray Observations
  71. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  72. GRB 010220, simultaneous optical observations
  73. GRB010220: BeppoSAX WFC and GRBM preliminary data
  74. GRB010214, candidate optical afterglow
  75. GRB010214, optical observations
  76. BeppoSAX ALERT: GRB010220
  77. GRB010214: BeppoSAX WFC and GRBM preliminary data
  78. GRB 010214: X-Ray afterglow
  79. GRB 010214, Optical Observations
  80. GRB 010214 optical observation
  81. GRB010213 Optical Observation
  82. GRB010214, optical observations
  83. Possible InfraRed Transient of GRB 010214.
  84. GRB010214: BeppoSAX/NFI Observations
  85. GRB010213 detected by HETE
  86. BeppoSAX ALERT: GRB010214
  87. IPN Status Report
  88. HETE Status
  89. GRB010126 opt. obs.
  90. GRB010126: CONCAM crude optical limits during GRB
  91. GRB010126, TNG R-band observations
  92. GRB010126 Optical Observations
  93. GRB010126 optical observations
  94. IPN/RXTE TRIANGULATION OF GRB010126
  95. GRB 010119, optical observations
  96. Optical Observations of GRB 001018 at Keck
  97. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  98. Optical observations of GRB 001018 with JCAM
  99. IPN TRIANGULATION OF GRB010115
  100. IPN TRIANGULATION OF GRB010109

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