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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"

24913 results found.

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

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