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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"

25840 results found.

  1. SGR1806-20: A Second, Intense Burst Localized by HETE
  2. GRB 00630: Host Galaxy
  3. SGR1806-20: Localization by HETE
  4. IPN triangulation of GRB010613
  5. IPN triangulation of GRB010612
  6. HETE Fully-Automated GCN Notices
  7. GRB000301C: Late-time HST/STIS observation
  8. GRB010518: a faint BeppoSAX detection
  9. GRB000418: HST/STIS Second-epoch Observations
  10. X-ray precursors to the large flare from SGR 1900+14
  11. GRB010427, Gamma Ray Observations
  12. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  13. SGR 1900+14: Correction to GCN 1049
  14. Millimeter observation of SGR 1900+14
  15. SGR 1900+14: Detection of extended X-ray emission
  16. Chandra Observations of SGR 1900+14
  17. SGR 1900+14, Chandra observations
  18. Chandra Observations of SGR 1900+14
  19. Possible precursor to the SGR1900+14 giant burst
  20. SGR1900+14, I-band observations
  21. IPN Triangulation of the Giant Flare from SGR1900+14
  22. GRB010412, field photometry
  23. Giant flare from SGR1900+14
  24. GRB 010326b Optical Observations
  25. GRB010412: BeppoSAX GRBM and WFC observations
  26. IPN Triangulation of GRB010412
  27. GRB Observation Report
  28. GRB010324, revised field photometry
  29. GRB 980326: Late-time HST/STIS observations
  30. GRB010324, field photometry
  31. GRB010326B, field photometry
  32. GRB010326, field photometry
  33. GRB010220, field photometry
  34. Further Optical Observations of GRB 010324
  35. GRB010222, CXO X-ray observations
  36. GRB 010326A: Further optical observations
  37. GRB010324: BeppoSAX/GRBM data
  38. GRB 010326B: Optical observations
  39. GRB010324, optical observations
  40. GRB010326B: Localization by HETE (2nd GRB for this date)
  41. GRB 010326: Optical observations
  42. GRB 010326 optical observations
  43. GRB010326: Refined Localization by HETE
  44. GRB010326: Localization by HETE
  45. Duration, ECT, peak flux and fluence of GRB010324
  46. Optical Observations of GRB 010324
  47. GRB990705, VLT-FORS1 observations of the host galaxy
  48. GRB010222, late-time optical observation
  49. Support extension to the BeppoSAX mission
  50. GRB 010222 - HEGRA GeV/TeV Observations
  51. GRB010222: Sub-millimeter vanishing act
  52. GRB010222 - Optical observation
  53. GRB 010222, Optical Observations
  54. GRB 010222: High-Resolution Keck Spectroscopy
  55. GRB 010214, I-band data
  56. GRB 010222
  57. GRB010222 further R-band photometry
  58. GRB 010222: Keck Spectroscopy
  59. GRB010214, field photometry
  60. GRB010222, field photometry
  61. GRB010222 further R-band photometry
  62. GRB010222, possible increase of optical decay slope
  63. GRB 010222 Kyoto optical observation
  64. GRB010222 R-BAND OBSERVATION
  65. GRB010214 follow-up from Hanle
  66. GRB 010222: Near-IR Observations
  67. GRB 010222: Optical Observations
  68. GRB 010222, Decay Slope Confirmed
  69. GRB 010214, Optical Observations
  70. GRB010222, radio observations
  71. GRB010222, optical 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 Optical Observation
  81. J-Band Observation of GRB 010214.
  82. GRB010213, Near-IR observations
  83. Possible InfraRed Transient of GRB 010214.
  84. GRB010214 Optical Observation
  85. GRB010213 detected by HETE
  86. IPN Status Report
  87. HETE Status
  88. IPN/RXTE TRIANGULATION OF GRB010126
  89. GRB010126: CONCAM crude optical limits during GRB
  90. GRB010126 Optical Observations
  91. GRB010126 optical observations
  92. GRB010126: Optical observations
  93. IPN TRIANGULATION OF GRB010126
  94. IPN/RXTE TRIANGULATION OF GRB010126
  95. GRB 010119, optical observations
  96. GRB010119: Optical observations
  97. Optical Observations of GRB 001018 at Keck
  98. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  99. Optical observations of GRB 001018 with JCAM
  100. IPN TRIANGULATION OF GRB010115

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