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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"

44618 results found.

  1. GRB 991216 VLBA Observations
  2. BEPPOSAX GRBM Localization of GRB991226
  3. IPN error boxes for GRB991229
  4. GRB 991216: J band spectrophotometry
  5. GRB 991216: Detection of the Host and/or Absorber Galaxy
  6. IPN localization of GRB991226
  7. Single IPN error box for GRB991221
  8. IPN error boxes for GRB991221
  9. GRB 991216 RXTE ASM Observations
  10. IPN error box for GRB991216
  11. GRB 991216: Updated BATSE parameters
  12. Lowell/Perkins observation of GRB 991216
  13. GRB 991217 (SAX J2303.2+0015) Optical observations
  14. GRB991217/SAX J2303.2+0015, optical observations
  15. Chandra observation of the X-ray afterglow of GRB991216
  16. GRB 991216, optical observations
  17. GRB 991216 Optical Observations
  18. GRB 991216 Optical spectroscopy/imaging
  19. VLT spectra of GRB991216
  20. GRB991216 Optical and IR observations
  21. K observations of GRB991216
  22. SAX J2303.2+0015 Optical observations
  23. IR observations of GRB991216
  24. GRB991216 radio observations
  25. GRB 991217 (SAX J2303.2+0015) Optical observations
  26. GRB991216 radio observations
  27. GRB991216 Spectroscopy
  28. Lowell/Perkins observation of GRB 991216
  29. GRB991216, optical observations
  30. GRB991216 Optical and infrared observations of Beethoven Burst
  31. Refined IPN localization of GRB991216
  32. GRB 991216 Radio Observations
  33. GRB 991217
  34. GRB 991208 Keck Spectroscopy
  35. GRB 991208 Infrared Detection
  36. GRB991216
  37. GRB 991216--Summary of RXTE Observations
  38. GRB 991216 Optical Observations
  39. GRB 991216, optical observations
  40. GRB 991208 SAO-RAS Spectroscopy
  41. SAX J2303.2+0015: an x-ray/GRB?
  42. GRB 991216, Optical Transient
  43. GRB 991216, Optical Afterglow
  44. GRB991216 ('Beethoven Burst') B, R, and K Observations
  45. GRB 991216: Comparison with DPOSS images
  46. GRB991216, infrared observations
  47. GRB991216 Optical Observations
  48. GRB 991208 optical observations
  49. Lowell/Perkins observation of GRB 991216
  50. GRB 991216 Optical Observation
  51. GRB 991208 Keck Spectroscopy
  52. GRB 991216: Extremely bright BATSE burst
  53. R-band Observations of GRB991208 at TNG
  54. GRB991208, optical observations
  55. GRB 991208 Keck Spectroscopy
  56. GRB991208 - millimeter detection
  57. GRB 991208, Optical Observation
  58. GRB991208 15-GHz observations
  59. GRB991208, optical observations
  60. GRB 991208 - OVRO detection
  61. GRB 991208 Optical Decay
  62. GRB 991208 optical observations
  63. GRB 991208 optical observations
  64. GRB 991208: Radio Observations
  65. IPN localization of GRB991208
  66. Optical Observations of GRB991105
  67. GRB991106: BeppoSAX/BATSE results
  68. GRB 991106, optical observations
  69. GRB991106, near-infrared observations
  70. BeppoSAX NFI Observation of GRB991106
  71. GRB 991106, radio observations
  72. GRB991106: the first BeppoSAX short GRB detection?
  73. GRB 991105: BATSE Observations
  74. IPN localization of GRB991105
  75. GRB 991106 Optical Observations
  76. GRB 991105, optical observations
  77. GRB991106, optical observation at SAO-RAS
  78. GRB 991106, LOTIS Optical Observations
  79. GRB 991106, optical observations
  80. BeppoSAX refined position for GRB991106
  81. BeppoSAX GRB Alert: GRB991106
  82. Revised BeppoSAX WFC position of GRB991105
  83. GRB991105: SAX-GRBM/-WFC detection
  84. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  85. GRB ALERT: GRB991105
  86. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  87. GRB 991014, Optical Observations
  88. GRB 991014 - BeppoSAX NFI observations
  89. GRB 991014, Optical Observations
  90. GRB 991014, radio observations
  91. GRB991014 BATSE Observations
  92. GRB 991014, Optical Observations
  93. GRB 991014, optical observations
  94. Super-LOTIS optical observation of GRB991014
  95. IPN/NFI error box for GRB991014
  96. IPN localization of GRB991014 - CORRECTION
  97. IPN localization of GRB991014
  98. BeppoSAX ALERT: GRB991014
  99. GRB 990915 optical observations
  100. GRB 990907 optical observations

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