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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"

19042 results found.

  1. GRB 000301c near-IR observations
  2. GRB 000301C, UBVRI field photometry
  3. GRB000301C, near-infrared observations (JHK' photometry)
  4. GRB 000301C: OT confirmed
  5. GRB000301c optical observations
  6. GRB000301C
  7. GRB 000301C : Optical Candidate
  8. HST Observations of GRB 990712
  9. GRB 000214 near-IR observations
  10. GRB 000214, Radio Observations
  11. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  12. GRB000210, Radio Observations
  13. GRB 000115, BVRI field photometry
  14. GRB000214: BeppoSAX GRBM and WFC Detection
  15. Optical observations of GRB000210
  16. GRB000210 X-ray afterglow
  17. GRB000214: X-ray afterglow candidate
  18. GRB000214 refined BeppoSAX-WFC position
  19. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  20. Correction to Chandra Position of GRB000210 afterglow
  21. Optical observations of the Chandra X-ray source for GRB000210
  22. GRB000210, Radio Observations
  23. GRB000210: possible afterglow detection with BeppoSAX NFI
  24. GRB000201, Radio Observations
  25. GRB000210: BeppoSAX GRBM and WFC Detection
  26. GRB000201 Optical Observations
  27. GRB 000126, optical observations
  28. IPN localization of GRB000126
  29. IPN annulus for GRB000115
  30. GRB991216, UBVRIJHK field photometry
  31. GCN resumes full operations
  32. GRB 991216: Detection of the Host and/or Absorber Galaxy
  33. GRB 991216 RXTE ASM Observations
  34. GRB 991217 (SAX J2303.2+0015) Optical observations
  35. Chandra observation of the X-ray afterglow of GRB991216
  36. SAX J2303.2+0015 Optical observations
  37. IR observations of GRB991216
  38. GRB 991217 (SAX J2303.2+0015) Optical observations
  39. GRB 991216 Radio Observations
  40. GRB 991208 Infrared Detection
  41. GRB991216
  42. GRB 991216--Summary of RXTE Observations
  43. GRB 991216 Optical Observations
  44. GRB 991216, optical observations
  45. GRB 991208 SAO-RAS Spectroscopy
  46. SAX J2303.2+0015: an x-ray/GRB?
  47. GRB 991216, Optical Transient
  48. GRB991216 ('Beethoven Burst') B, R, and K Observations
  49. GRB991216, infrared observations
  50. GRB 991208 optical observations
  51. GRB 991216 Optical Observation
  52. GRB 991216: Extremely bright BATSE burst
  53. R-band Observations of GRB991208 at TNG
  54. GRB991208, optical observations
  55. GRB 991208, Optical Observation
  56. GRB991208, optical observations
  57. IPN localization of GRB991208
  58. Optical Observations of GRB991105
  59. GRB991106: BeppoSAX/BATSE results
  60. BeppoSAX NFI Observation of GRB991106
  61. GRB 991106, radio observations
  62. GRB991106: the first BeppoSAX short GRB detection?
  63. GRB 991106 Optical Observations
  64. GRB991106, optical observation at SAO-RAS
  65. GRB 991106, LOTIS Optical Observations
  66. GRB991105: SAX-GRBM/-WFC detection
  67. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  68. GRB 991014, Optical Observations
  69. GRB 991014 - BeppoSAX NFI observations
  70. GRB 991014, radio observations
  71. GRB 991014, Optical Observations
  72. GRB 991014, optical observations
  73. Optical Observations of GRB990907
  74. GRB990907: BeppoSAX follow up and X-ray afterglow
  75. GRB990907 and 990908
  76. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  77. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  78. GRB990806 BeppoSAX follow up
  79. GRB 990806 Optical observations
  80. GRB 990806, optical observations
  81. GRB 990806, Optical Observations
  82. GRB990806: possible X-ray afterglow, BeppoSAX
  83. GRB 990712 Optical Observations
  84. GRB 990712
  85. Late-time HST/STIS Observations of GRB 990510
  86. BeppoSAX NFI Observation of GRB990705
  87. BeppoSAX NFI Observation of GRB990705
  88. GRB 990705, R-band observations
  89. GRB990704: SAX-NFI results summary
  90. GRB990704 radio and optical observations
  91. GRB990704
  92. GRB990704, optical observations
  93. GRB990704: possible X-ray afterglow
  94. GRB990704
  95. GRB990704: BeppoSAX detection
  96. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  97. GRB 990627, radio observations
  98. Late-time HST/STIS Observation of GRB 990123
  99. Optical Observations of GRB 990506
  100. GRB 990506 Radio Transient

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