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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"

11836 results found.

  1. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  2. GRB000926 K'-band Observation
  3. IPN triangulation of GRB000925
  4. IPN triangulation of GRB000910
  5. IPN triangulation of GRB000830
  6. HST/STIS observations of the host galaxy of GRB 980329
  7. SGR 1806-20 burst activity
  8. GRB000801 & GRB000730, Gamma Ray Observations
  9. GRB000730, Gamma Ray Observations
  10. GRB000801, Gamma Ray Observations
  11. possible optical counterpart of GRB 000630
  12. IPN triangulation of GRB000630
  13. GRB 000623, optical observations
  14. GRB000620, optical observations
  15. GRB000620: BeppoSAX WFC and GRBM detection
  16. BeppoSAX ALERT: GRB000620
  17. GRB000620: BeppoSAX Alert
  18. GRB000616 [IPN Position]
  19. GRB000615B [IPN Position]
  20. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  21. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  22. GRB000519: Optical observations
  23. IPN triangulation of GRB000516
  24. GRB 000429, optical observation
  25. GRB 000418, UBVRI field photometry
  26. GRB 000418, Optical Observation
  27. GRB 000418, optical observation
  28. GRB 000418, Optical Observation
  29. GRB 000418, Optical Observation
  30. GRB000418, near-infrared observations
  31. IPN error box for GRB000418
  32. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  33. GRB 000408, optical observations
  34. GRB000313, Radio observations
  35. GRB000301C - B and R photometry
  36. GRB 000307, BVRI Field Photometry
  37. IPN error box for GRB000307
  38. GRB 000301C, UBVRI field photometry
  39. GRB 000301C, Optical Observation
  40. GRB 000301A, Radio Observations
  41. GRB 000301C : Optical Candidate
  42. GRB000226 [IPN Position]
  43. GRB 000115 Optical observations
  44. BATSE GRB trigger criterion changed
  45. GRB 000210: BATSE Observations
  46. GRB000210: BeppoSAX GRBM and WFC Detection
  47. GRB000201 Optical Observations
  48. BATSE Observations of GRB000115
  49. GCN resumes full operations
  50. Chandra observation of the X-ray afterglow of GRB991216
  51. GRB 991216 Optical spectroscopy/imaging
  52. GRB 991216 Optical Observation
  53. GRB 991216: Extremely bright BATSE burst
  54. IPN localization of GRB991208
  55. GRB 991105: BATSE Observations
  56. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  57. GRB 990915 optical observations
  58. BATSE GRB trigger criteria
  59. GRB990907: BeppoSAX follow up and X-ray afterglow
  60. GRB990806: BATSE Observations
  61. GRB 990705, R-band observations
  62. Infrared and Optical Observations of GRB990705
  63. GRB990704
  64. Refined BeppoSAX-WFC position of GRB990704
  65. GRB990704: BeppoSAX detection
  66. IPN error box for GRB990527
  67. Late Afterglows of GRBs 990510, 990123
  68. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  69. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  70. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  71. BeppoSAX: A new fast X-ray transient
  72. VLT spectrum of GRB990510
  73. GRB 990510: BATSE Observations
  74. GRB990510
  75. GRB 990506: BATSE Observations
  76. GRB 990506, optical observations
  77. GRB990506 Optical observations
  78. New IPN/RXTE error box for GRB990506
  79. GRB 970228: Redshift and properties of the host galaxy
  80. GRB980425 Optical observations of exponential decline at late time
  81. GRB990323 PRECISE IPN POSITION
  82. GRB990321 IPN TRIANGULATION
  83. GRB990308 not a new SGR
  84. GRB990308, Possible new SGR~0209+70
  85. GRB 981220, radio observations
  86. BATSE Flight Anomaly
  87. Optical Observations of GRB990217
  88. GRB 990123: Continued Radio Observations
  89. Search for Potential Images of GRB 990123
  90. "GRB 990123: New BV Observations"
  91. GRB 990123: BATSE Observations
  92. GRB990123 Optical Observation
  93. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  94. GRB 980613: Spectroscopy of the host galaxy
  95. GRB 981226 optical observations
  96. GRB981226, BeppoSAX-NFI follow-up
  97. GRB 981220: BeppoSAX/GRBM results
  98. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  99. GRB 980923 BATSE Observations
  100. SGR1900+14, BeppoSAX-GRBM observations

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