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

Advanced

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