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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"
  1. GRB000301C, Radio observations
  2. GRB000301C optical observations
  3. GRB000301C, near-infrared observations (JHK' imaging)
  4. GRB 000301c near-IR observations
  5. GRB 000301C, Optical Color
  6. GRB000301C, Optical Spectroscopy
  7. GRB 000301C, UBVRI field photometry
  8. GRB 000301C, Optical Observation
  9. GRB000301C, optical observations
  10. GRB000301C 250 GHz detection
  11. GRB 000301C R-band observation
  12. GRB 000301C, Optical Observation
  13. GRB000301C, near-infrared observations (JHK' photometry)
  14. GRB 000301C: OT confirmed
  15. GRB000301c optical observations
  16. GRB 000301A, Radio Observations
  17. GRB000301C, optical observations
  18. GRB000301c, near-infrared observations
  19. GRB000301C
  20. GRB 000301C : Optical Candidate
  21. Radio observations of the error box of GRB000301A
  22. GRB000301C: RXTE/ASM and IPN localizations
  23. GRB000301A [IPN Position]
  24. GRB000226 [IPN Position]
  25. HST Observations of GRB 990712
  26. GRB 000214 near-IR observations
  27. GRB 000115 Optical observations
  28. GRB 000214, Radio Observations
  29. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  30. GRB000210, Radio Observations
  31. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  32. GRB 000115, BVRI field photometry
  33. GRB000214: BeppoSAX GRBM and WFC Detection
  34. IPN annulus for GRB000214
  35. BATSE GRB trigger criterion changed
  36. Optical observations of GRB000210
  37. GRB000210 X-ray afterglow
  38. GRB000214: X-ray afterglow candidate
  39. GRB000214 refined BeppoSAX-WFC position
  40. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  41. GRB 000210: BATSE Observations
  42. Correction to Chandra Position of GRB000210 afterglow
  43. Optical observations of the Chandra X-ray source for GRB000210
  44. GRB000210, Radio Observations
  45. Optical candidate for GRB000210
  46. Chandra Observations of GRB000210 X-ray Afterglow
  47. IPN triangulation of GRB000210
  48. GRB000210: possible afterglow detection with BeppoSAX NFI
  49. GRB000201, Radio Observations
  50. GRB000210: BeppoSAX GRBM and WFC Detection
  51. SAX_WFC_GRB_NOTICE
  52. SAX_WFC_GRB_NOTICE
  53. Optical observations of GRB000131
  54. GRB000201 Optical Observations
  55. GRB 000201: TAROT optical observations
  56. GRB 000131 Optical Observations
  57. GRB000126 Optical Observations
  58. BATSE GRB trigger criteria changed
  59. GRB 991208, radio observations
  60. BATSE+IPN location of GRB000131
  61. IPN localization of GRB000131
  62. GRB 000126, optical observations
  63. GRB000126, optical observations
  64. BATSE location of GRB000126
  65. IPN localization of GRB000126
  66. GRB 000115 Optical observations
  67. BATSE Observations of GRB000115
  68. Correction to GCN 520 (IPN annulus for GRB000115)
  69. IPN annulus for GRB000115
  70. Second RXTE Observation of GRB 000115
  71. GRB991216, UBVRIJHK field photometry
  72. GRB991216 late optical observation
  73. Single IPN error box for GRB991229
  74. GCN resumes full operations
  75. GRB 991216 VLBA Observations
  76. BEPPOSAX GRBM Localization of GRB991226
  77. IPN error boxes for GRB991229
  78. GRB 991216: J band spectrophotometry
  79. GRB 991216: Detection of the Host and/or Absorber Galaxy
  80. IPN localization of GRB991226
  81. Single IPN error box for GRB991221
  82. IPN error boxes for GRB991221
  83. GRB 991216 RXTE ASM Observations
  84. IPN error box for GRB991216
  85. GRB 991216: Updated BATSE parameters
  86. Lowell/Perkins observation of GRB 991216
  87. GRB 991217 (SAX J2303.2+0015) Optical observations
  88. GRB991217/SAX J2303.2+0015, optical observations
  89. Chandra observation of the X-ray afterglow of GRB991216
  90. GRB 991216, optical observations
  91. GRB 991216 Optical Observations
  92. GRB 991216 Optical spectroscopy/imaging
  93. VLT spectra of GRB991216
  94. GRB991216 Optical and IR observations
  95. K observations of GRB991216
  96. SAX J2303.2+0015 Optical observations
  97. IR observations of GRB991216
  98. GRB991216 radio observations
  99. GRB 991217 (SAX J2303.2+0015) Optical observations
  100. GRB991216 radio observations

Advanced

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