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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"

26314 results found.

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

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