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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"

26366 results found.

  1. SGR1900+14 burst seen by HETE: BeppoSAX data
  2. GRB 010629 Optical Observations
  3. SGR1900+14: High Fluence Burst Localized by HETE
  4. GRB010629, optical observations
  5. GRB010629: A Burst Localized by HETE
  6. SGR1900+14: Second Burst Localized by HETE
  7. SGR1900+14: A Burst Localized by HETE
  8. SGR1806-20: A Second, Intense Burst Localized by HETE
  9. SGR1806-20: Localization by HETE
  10. HETE Fully-Automated GCN Notices
  11. GRB000301C: Late-time HST/STIS observation
  12. GRB010518: a faint BeppoSAX detection
  13. GRB000418: HST/STIS Second-epoch Observations
  14. X-ray precursors to the large flare from SGR 1900+14
  15. GRB010427, Gamma Ray Observations
  16. SGR 1900+14: No evidence of extended X-ray emission
  17. SGR 1900+14 : RXTE observations
  18. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  19. SGR 1900+14: Correction to GCN 1049
  20. GRB 010222 /corrections to VBT data
  21. Millimeter observation of SGR 1900+14
  22. SGR 1900+14: Detection of extended X-ray emission
  23. SGR 1900+14, Chandra observations
  24. SGR1900+14, I-band observations
  25. GRB010412, field photometry
  26. Giant flare from SGR1900+14
  27. GRB 010326b Optical Observations
  28. GRB010412: BeppoSAX GRBM and WFC observations
  29. GRB010324, revised field photometry
  30. REVISED LOCATION OF GRB010326A
  31. GRB 980326: Late-time HST/STIS observations
  32. GRB010324, field photometry
  33. GRB010326B, field photometry
  34. GRB010326, field photometry
  35. GRB010220, field photometry
  36. Further Optical Observations of GRB 010324
  37. GRB010222, CXO X-ray observations
  38. GRB010324, optical observations
  39. GRB010326B: Localization by HETE (2nd GRB for this date)
  40. GRB 010326 optical observations
  41. GRB010326: Refined Localization by HETE
  42. GRB010326: Localization by HETE
  43. Optical Observations of GRB 010324
  44. GRB010222, late-time optical observation
  45. Support extension to the BeppoSAX mission
  46. GRB 010222 - HEGRA GeV/TeV Observations
  47. GRB010222: Chandra X-ray Observatory Observation
  48. GRB010222: Sub-millimeter vanishing act
  49. GRB010222 - Optical observation
  50. GRB 010222, Optical Observations
  51. GRB010222 - Optical observation
  52. GRB 010222: High-Resolution Keck Spectroscopy
  53. GRB 010214, I-band data
  54. GRB 010222
  55. GRB010222 further R-band photometry
  56. GRB010222: R-band data
  57. GRB 010222: Keck Spectroscopy
  58. GRB010214, field photometry
  59. GRB010222, field photometry
  60. GRB010222 further R-band photometry
  61. GRB010222, possible increase of optical decay slope
  62. GRB 010222 Kyoto optical observation
  63. GRB010222 R-BAND OBSERVATION
  64. GRB010214 follow-up from Hanle
  65. GRB 010222: Near-IR Observations
  66. GRB 010222: Optical Observations
  67. GRB010222: Optical decay slope
  68. GRB 010214, Optical Observations
  69. GRB010222, radio observations
  70. GRB010222, optical observations
  71. GRB010222: BeppoSAX/NFI Observations
  72. GRB010214B,Gamma Ray Observations
  73. GRB 010220, simultaneous optical observations
  74. GRB010220: BeppoSAX WFC and GRBM preliminary data
  75. GRB010214, candidate optical afterglow
  76. GRB010214, optical observations
  77. GRB010214: BeppoSAX WFC and GRBM preliminary data
  78. GRB 010214: X-Ray afterglow
  79. GRB 010214 optical observation
  80. GRB010213, Radio Observations
  81. J-Band Observation of GRB 010214.
  82. GRB010213, Near-IR observations
  83. Possible InfraRed Transient of GRB 010214.
  84. GRB 010214, optical observations
  85. GRB010213 detected by HETE
  86. IPN Status Report
  87. HETE Status
  88. IPN/RXTE TRIANGULATION OF GRB010126
  89. GRB010126 Optical Observations
  90. IPN TRIANGULATION OF GRB010126
  91. Optical Observations of GRB 001018 at Keck
  92. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  93. Optical observations of GRB 001018 with JCAM
  94. IPN TRIANGULATION OF GRB010115
  95. IPN TRIANGULATION OF GRB010109
  96. IPN TRIANGULATION OF GRB010109
  97. IPN triangulation of GRB010104
  98. IPN triangulation of GRB010103
  99. H band observation of GRB 001212
  100. IPN triangulation of GRB001219

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