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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"

26011 results found.

  1. GRB000301C, near-infrared observations (JHK' imaging)
  2. GRB 000301c near-IR observations
  3. GRB 000301C, UBVRI field photometry
  4. GRB 000301C: OT confirmed
  5. GRB000301c optical observations
  6. GRB000301C, optical observations
  7. GRB000301C
  8. GRB 000301C : Optical Candidate
  9. GRB000301C: RXTE/ASM and IPN localizations
  10. GRB000226 [IPN Position]
  11. HST Observations of GRB 990712
  12. GRB 000214 near-IR observations
  13. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  14. GRB000210, Radio Observations
  15. GRB 000115, BVRI field photometry
  16. GRB000214: BeppoSAX GRBM and WFC Detection
  17. Optical observations of GRB000210
  18. GRB000210 X-ray afterglow
  19. GRB000214: X-ray afterglow candidate
  20. GRB000214 refined BeppoSAX-WFC position
  21. GRB 000210: BATSE Observations
  22. Optical observations of the Chandra X-ray source for GRB000210
  23. GRB000210, Radio Observations
  24. IPN triangulation of GRB000210
  25. GRB000210: possible afterglow detection with BeppoSAX NFI
  26. GRB000201, Radio Observations
  27. GRB000210: BeppoSAX GRBM and WFC Detection
  28. SAX_WFC_GRB_NOTICE
  29. SAX_WFC_GRB_NOTICE
  30. GRB000201 Optical Observations
  31. GRB 000201: TAROT optical observations
  32. GRB 991208, radio observations
  33. BATSE+IPN location of GRB000131
  34. IPN localization of GRB000131
  35. GRB 000126, optical observations
  36. BATSE Observations of GRB000115
  37. Second RXTE Observation of GRB 000115
  38. GRB991216, UBVRIJHK field photometry
  39. GCN resumes full operations
  40. GRB 991216 VLBA Observations
  41. GRB 991216: J band spectrophotometry
  42. GRB 991216: Detection of the Host and/or Absorber Galaxy
  43. IPN localization of GRB991226
  44. GRB 991216 RXTE ASM Observations
  45. GRB 991216: Updated BATSE parameters
  46. GRB 991217 (SAX J2303.2+0015) Optical observations
  47. Chandra observation of the X-ray afterglow of GRB991216
  48. GRB 991216, optical observations
  49. GRB 991216 Optical spectroscopy/imaging
  50. SAX J2303.2+0015 Optical observations
  51. IR observations of GRB991216
  52. GRB 991217 (SAX J2303.2+0015) Optical observations
  53. GRB991216 Optical and infrared observations of Beethoven Burst
  54. GRB 991216 Radio Observations
  55. GRB 991208 Keck Spectroscopy
  56. GRB 991208 Infrared Detection
  57. GRB991216
  58. GRB 991216--Summary of RXTE Observations
  59. GRB 991216 Optical Observations
  60. GRB 991216, optical observations
  61. GRB 991208 SAO-RAS Spectroscopy
  62. SAX J2303.2+0015: an x-ray/GRB?
  63. GRB 991216, Optical Transient
  64. GRB991216 ('Beethoven Burst') B, R, and K Observations
  65. GRB991216, infrared observations
  66. GRB 991208 optical observations
  67. GRB 991216 Optical Observation
  68. GRB 991216: Extremely bright BATSE burst
  69. R-band Observations of GRB991208 at TNG
  70. GRB991208, optical observations
  71. GRB 991208, Optical Observation
  72. GRB991208, optical observations
  73. GRB 991208 optical observations
  74. Optical Observations of GRB991105
  75. GRB991106: BeppoSAX/BATSE results
  76. GRB991106, near-infrared observations
  77. BeppoSAX NFI Observation of GRB991106
  78. GRB 991106, radio observations
  79. GRB991106: the first BeppoSAX short GRB detection?
  80. GRB 991105: BATSE Observations
  81. GRB 991106 Optical Observations
  82. GRB991106, optical observation at SAO-RAS
  83. GRB 991106, LOTIS Optical Observations
  84. GRB991105: SAX-GRBM/-WFC detection
  85. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  86. GRB 991014, Optical Observations
  87. GRB 991014 - BeppoSAX NFI observations
  88. GRB 991014, radio observations
  89. GRB 991014, Optical Observations
  90. GRB 991014, optical observations
  91. GRB 990915 optical observations
  92. Optical Observations of GRB990907
  93. GRB990907: BeppoSAX follow up and X-ray afterglow
  94. GRB990907 and 990908
  95. GRB 990712 Late Optical Decay and Host Galaxy
  96. GRB990806 BeppoSAX follow up
  97. GRB990806: BATSE Observations
  98. GRB 990806 Optical observations
  99. GRB 990806, Optical Observations
  100. GRB 990806, optical observations

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