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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"

23406 results found.

  1. IPN error box for GRB000307
  2. GRB000301C, optical R-band observations
  3. GRB 000301C Optical Observations
  4. GRB 000301C: K' Observations
  5. GRB000301C OT candidate optical observations
  6. GRB000301C - Host galaxy not detected in R (?)
  7. Optical observations of GRB000301c
  8. GRB000301C, Radio observations
  9. GRB000301C, Radio observations
  10. GRB 000301c near-IR observations
  11. GRB 000301C, Optical Color
  12. GRB 000301C, UBVRI field photometry
  13. GRB000301C, near-infrared observations (JHK' photometry)
  14. GRB 000301C: OT confirmed
  15. GRB000301c optical observations
  16. GRB000301c, near-infrared observations
  17. GRB000301C
  18. GRB 000301C : Optical Candidate
  19. GRB000301C: RXTE/ASM and IPN localizations
  20. GRB000301A [IPN Position]
  21. GRB000226 [IPN Position]
  22. HST Observations of GRB 990712
  23. GRB 000214 near-IR observations
  24. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  25. GRB000210, Radio Observations
  26. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  27. GRB 000115, BVRI field photometry
  28. GRB000214: BeppoSAX GRBM and WFC Detection
  29. IPN annulus for GRB000214
  30. BATSE GRB trigger criterion changed
  31. Optical observations of GRB000210
  32. GRB000210 X-ray afterglow
  33. GRB000214: X-ray afterglow candidate
  34. GRB000214 refined BeppoSAX-WFC position
  35. GRB 000210: BATSE Observations
  36. Optical observations of the Chandra X-ray source for GRB000210
  37. GRB000210, Radio Observations
  38. GRB000201, Radio Observations
  39. GRB000210: BeppoSAX GRBM and WFC Detection
  40. GRB000201 Optical Observations
  41. BATSE+IPN location of GRB000131
  42. IPN localization of GRB000131
  43. GRB 000126, optical observations
  44. IPN annulus for GRB000115
  45. GRB991216, UBVRIJHK field photometry
  46. GCN resumes full operations
  47. GRB 991216: Detection of the Host and/or Absorber Galaxy
  48. IPN error box for GRB991216
  49. GRB 991216: Updated BATSE parameters
  50. GRB 991217 (SAX J2303.2+0015) Optical observations
  51. Chandra observation of the X-ray afterglow of GRB991216
  52. SAX J2303.2+0015 Optical observations
  53. IR observations of GRB991216
  54. GRB 991217 (SAX J2303.2+0015) Optical observations
  55. Refined IPN localization of GRB991216
  56. GRB 991216 Radio Observations
  57. GRB 991208 Infrared Detection
  58. GRB991216
  59. GRB 991216--Summary of RXTE Observations
  60. GRB 991216 Optical Observations
  61. GRB 991216, optical observations
  62. GRB 991208 SAO-RAS Spectroscopy
  63. SAX J2303.2+0015: an x-ray/GRB?
  64. GRB 991216, Optical Transient
  65. GRB991216 ('Beethoven Burst') B, R, and K Observations
  66. GRB991216, infrared observations
  67. GRB 991208 optical observations
  68. GRB 991216 Optical Observation
  69. GRB 991216: Extremely bright BATSE burst
  70. GRB991208, optical observations
  71. GRB 991208, Optical Observation
  72. GRB991208, optical observations
  73. GRB 991208 Optical Decay
  74. Optical Observations of GRB991105
  75. GRB 991106, optical observations
  76. BeppoSAX NFI Observation of GRB991106
  77. GRB 991106, radio observations
  78. GRB991106: the first BeppoSAX short GRB detection?
  79. IPN localization of GRB991105
  80. GRB 991106 Optical Observations
  81. GRB991106, optical observation at SAO-RAS
  82. GRB 991106, LOTIS Optical Observations
  83. GRB991105: SAX-GRBM/-WFC detection
  84. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  85. GRB 991014, Optical Observations
  86. GRB 991014 - BeppoSAX NFI observations
  87. GRB 991014, radio observations
  88. GRB 991014, Optical Observations
  89. GRB 991014, optical observations
  90. IPN localization of GRB991014 - CORRECTION
  91. IPN localization of GRB991014
  92. Optical Observations of GRB990907
  93. IPN localization of BATSE #7766 (GRB990915)
  94. GRB990907: BeppoSAX follow up and X-ray afterglow
  95. GRB990907 and 990908
  96. IPN localization of GRB990907
  97. GRB990806 BeppoSAX follow up
  98. GRB 990806 Optical observations
  99. GRB 990806, Optical Observations
  100. GRB 990806, optical observations

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