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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"

27320 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. GRB000301C, near-infrared observations (JHK' imaging)
  11. GRB 000301c near-IR observations
  12. GRB 000301C, UBVRI field photometry
  13. GRB 000301C: OT confirmed
  14. GRB000301c optical observations
  15. GRB000301C, optical observations
  16. GRB000301C
  17. GRB 000301C : Optical Candidate
  18. GRB000301C: RXTE/ASM and IPN localizations
  19. GRB000226 [IPN Position]
  20. HST Observations of GRB 990712
  21. GRB 000214 near-IR observations
  22. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  23. GRB000210, Radio Observations
  24. GRB 000115, BVRI field photometry
  25. GRB000214: BeppoSAX GRBM and WFC Detection
  26. Optical observations of GRB000210
  27. GRB000210 X-ray afterglow
  28. GRB000214: X-ray afterglow candidate
  29. GRB000214 refined BeppoSAX-WFC position
  30. GRB 000210: BATSE Observations
  31. Optical observations of the Chandra X-ray source for GRB000210
  32. GRB000210, Radio Observations
  33. IPN triangulation of GRB000210
  34. GRB000210: possible afterglow detection with BeppoSAX NFI
  35. GRB000201, Radio Observations
  36. GRB000210: BeppoSAX GRBM and WFC Detection
  37. SAX_WFC_GRB_NOTICE
  38. SAX_WFC_GRB_NOTICE
  39. GRB000201 Optical Observations
  40. GRB 000201: TAROT optical observations
  41. GRB 991208, radio observations
  42. BATSE+IPN location of GRB000131
  43. IPN localization of GRB000131
  44. GRB 000126, optical observations
  45. BATSE Observations of GRB000115
  46. Second RXTE Observation of GRB 000115
  47. GRB991216, UBVRIJHK field photometry
  48. GCN resumes full operations
  49. GRB 991216 VLBA Observations
  50. GRB 991216: J band spectrophotometry
  51. GRB 991216: Detection of the Host and/or Absorber Galaxy
  52. IPN localization of GRB991226
  53. GRB 991216 RXTE ASM Observations
  54. GRB 991216: Updated BATSE parameters
  55. GRB 991217 (SAX J2303.2+0015) Optical observations
  56. Chandra observation of the X-ray afterglow of GRB991216
  57. GRB 991216, optical observations
  58. GRB 991216 Optical spectroscopy/imaging
  59. SAX J2303.2+0015 Optical observations
  60. IR observations of GRB991216
  61. GRB 991217 (SAX J2303.2+0015) Optical observations
  62. GRB991216 Optical and infrared observations of Beethoven Burst
  63. GRB 991216 Radio Observations
  64. GRB 991208 Keck Spectroscopy
  65. GRB 991208 Infrared Detection
  66. GRB991216
  67. GRB 991216--Summary of RXTE Observations
  68. GRB 991216 Optical Observations
  69. GRB 991216, optical observations
  70. GRB 991208 SAO-RAS Spectroscopy
  71. SAX J2303.2+0015: an x-ray/GRB?
  72. GRB 991216, Optical Transient
  73. GRB991216 ('Beethoven Burst') B, R, and K Observations
  74. GRB991216, infrared observations
  75. GRB 991208 optical observations
  76. GRB 991216 Optical Observation
  77. GRB 991216: Extremely bright BATSE burst
  78. R-band Observations of GRB991208 at TNG
  79. GRB991208, optical observations
  80. GRB 991208, Optical Observation
  81. GRB991208, optical observations
  82. GRB 991208 optical observations
  83. Optical Observations of GRB991105
  84. GRB991106: BeppoSAX/BATSE results
  85. GRB991106, near-infrared observations
  86. BeppoSAX NFI Observation of GRB991106
  87. GRB 991106, radio observations
  88. GRB991106: the first BeppoSAX short GRB detection?
  89. GRB 991105: BATSE Observations
  90. GRB 991106 Optical Observations
  91. GRB991106, optical observation at SAO-RAS
  92. GRB 991106, LOTIS Optical Observations
  93. GRB991105: SAX-GRBM/-WFC detection
  94. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  95. GRB 991014, Optical Observations
  96. GRB 991014 - BeppoSAX NFI observations
  97. GRB 991014, radio observations
  98. GRB 991014, Optical Observations
  99. GRB 991014, optical observations
  100. GRB 990915 optical observations

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