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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"

32502 results found.

  1. IPN annulus for GRB000214
  2. Optical observations of GRB000210
  3. GRB000210 X-ray afterglow
  4. GRB 000210: BATSE Observations
  5. Correction to Chandra Position of GRB000210 afterglow
  6. Optical observations of the Chandra X-ray source for GRB000210
  7. GRB000210, Radio Observations
  8. Optical candidate for GRB000210
  9. Chandra Observations of GRB000210 X-ray Afterglow
  10. IPN triangulation of GRB000210
  11. GRB000201, Radio Observations
  12. Optical observations of GRB000131
  13. GRB000201 Optical Observations
  14. GRB 000131 Optical Observations
  15. GRB000126 Optical Observations
  16. GRB 991208, radio observations
  17. BATSE+IPN location of GRB000131
  18. GRB 000126, optical observations
  19. GRB000126, optical observations
  20. BATSE location of GRB000126
  21. GRB 000115 Optical observations
  22. BATSE Observations of GRB000115
  23. Correction to GCN 520 (IPN annulus for GRB000115)
  24. IPN annulus for GRB000115
  25. GRB991216, UBVRIJHK field photometry
  26. GRB991216 late optical observation
  27. Single IPN error box for GRB991229
  28. GCN resumes full operations
  29. GRB 991216 VLBA Observations
  30. BEPPOSAX GRBM Localization of GRB991226
  31. GRB 991216: J band spectrophotometry
  32. GRB 991216: Detection of the Host and/or Absorber Galaxy
  33. Single IPN error box for GRB991221
  34. GRB 991216 RXTE ASM Observations
  35. IPN error box for GRB991216
  36. Lowell/Perkins observation of GRB 991216
  37. GRB 991217 (SAX J2303.2+0015) Optical observations
  38. GRB991217/SAX J2303.2+0015, optical observations
  39. Chandra observation of the X-ray afterglow of GRB991216
  40. GRB 991216, optical observations
  41. GRB 991216 Optical Observations
  42. GRB 991216 Optical spectroscopy/imaging
  43. VLT spectra of GRB991216
  44. GRB991216 Optical and IR observations
  45. SAX J2303.2+0015 Optical observations
  46. IR observations of GRB991216
  47. GRB991216 radio observations
  48. GRB 991217 (SAX J2303.2+0015) Optical observations
  49. GRB991216 radio observations
  50. Lowell/Perkins observation of GRB 991216
  51. GRB991216, optical observations
  52. Refined IPN localization of GRB991216
  53. GRB 991216 Radio Observations
  54. GRB 991208 Keck Spectroscopy
  55. GRB 991208 Infrared Detection
  56. GRB991216
  57. GRB 991216--Summary of RXTE Observations
  58. GRB 991216 Optical Observations
  59. GRB 991216, optical observations
  60. GRB 991208 SAO-RAS Spectroscopy
  61. GRB 991216, Optical Transient
  62. GRB 991216, Optical Afterglow
  63. GRB991216 ('Beethoven Burst') B, R, and K Observations
  64. GRB 991216: Comparison with DPOSS images
  65. GRB 991208 optical observations
  66. Lowell/Perkins observation of GRB 991216
  67. GRB 991216 Optical Observation
  68. GRB 991208 Keck Spectroscopy
  69. R-band Observations of GRB991208 at TNG
  70. GRB991208, optical observations
  71. GRB 991208 Keck Spectroscopy
  72. GRB991208 - millimeter detection
  73. GRB 991208, Optical Observation
  74. GRB991208 15-GHz observations
  75. GRB991208, optical observations
  76. GRB 991208 - OVRO detection
  77. GRB 991208 Optical Decay
  78. GRB 991208 optical observations
  79. GRB 991208 optical observations
  80. GRB 991208: Radio Observations
  81. Optical Observations of GRB991105
  82. GRB991106: BeppoSAX/BATSE results
  83. GRB 991106, optical observations
  84. GRB991106, near-infrared observations
  85. BeppoSAX NFI Observation of GRB991106
  86. GRB 991106, radio observations
  87. GRB 991105: BATSE Observations
  88. IPN localization of GRB991105
  89. GRB 991106 Optical Observations
  90. GRB 991105, optical observations
  91. GRB991106, optical observation at SAO-RAS
  92. GRB 991106, LOTIS Optical Observations
  93. GRB 991106, optical observations
  94. Revised BeppoSAX WFC position of GRB991105
  95. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  96. GRB 991014, Optical Observations
  97. GRB 991014 - BeppoSAX NFI observations
  98. GRB 991014, Optical Observations
  99. GRB 991014, Optical Observations
  100. GRB 991014, optical observations

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