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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"

23575 results found.

  1. GRB000519: Optical observations
  2. GRB000528: BeppoSAX GRBM observations
  3. GRB 000528 Optical Observations
  4. GRB000519, BVRI field photometry
  5. IPN triangulation of GRB000519
  6. IPN triangulation of GRB000516
  7. Re: GRB000508B : Optical observations
  8. GRB 000418, Optical observation
  9. GRB000508B, optical photometry
  10. GRB000508B, BVR field photometry
  11. Possible GRB-related phenomenon
  12. RXTE/ASM and IPN localization of GRB 000508B
  13. GRB000424, UBVRI field photometry
  14. GRB 000424 Optical Observations
  15. GRB000418, UBVRI field photometry update
  16. The redshift of GRB 000418
  17. GRB 000429, optical observation
  18. GRB 000429, UBVRI field photometry
  19. IPN localization of GRB000429
  20. GRB 000418, UBVRI field photometry
  21. GRB000418, K'-band photometry
  22. GRB 000418, Optical Observation
  23. GRB 000418, optical observation
  24. GRB000424 Optical Observations
  25. GRB 000418, Optical Observation
  26. GRB000424, optical observations
  27. GRB 000424, Optical Observations
  28. GRB000418, near-infrared observations
  29. Correction to IPN error box for GRB000419
  30. IPN error box for GRB000418
  31. GRB000419 [IPN Position]
  32. GRB000416 Optical Observations
  33. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  34. GRB000416 BRJK observations
  35. Refined IPN error box for GRB000408
  36. GRB 991208, UBVRI field photometry
  37. GRB000408: Optical CCD Observations from MIRO
  38. GRB000408, lotis optical observations
  39. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  40. GRB000408 [IPN Position]
  41. GRB000326 Optical Observations
  42. GRB000301C - R magnitude lower limit
  43. GRB 000323, optical observations
  44. GRB000326, Radio observations
  45. GRB000326 [IPN Position]
  46. GRB 000307 optical observations
  47. GRB000323 [IPN Position]
  48. Single error box for GRB000315
  49. GRB000315 [IPN Positions]
  50. GRB 000313 - optical transient in the BATSE error box
  51. GRB000301C - B and R photometry
  52. GRB000301C - R photometry
  53. GRB 000307, BVRI Field Photometry
  54. GRB 000301C: Optical Spectrum and Redshift
  55. GRB 000301C: Optical Spectrum and Redshift
  56. GRB 000301C: A Precise Redshift Determination
  57. IPN error box for GRB000307
  58. GRB 000301c: K' observations
  59. GRB000301C, optical R-band observations
  60. GRB000301c - R photometry and nearby faint source confirmation
  61. GRB 000301c: K' observations
  62. GRB 000301C: K' Observations
  63. GRB000301C OT candidate optical observations
  64. GRB000301C - Host galaxy not detected in R (?)
  65. GRB000301C optical observations
  66. GRB000301C, near-infrared observations (JHK' imaging)
  67. GRB000301C, Optical Spectroscopy
  68. GRB 000301C, UBVRI field photometry
  69. GRB000301C 250 GHz detection
  70. GRB 000301C R-band observation
  71. GRB000301c optical observations
  72. GRB000301C, optical observations
  73. GRB000301c, near-infrared observations
  74. Radio observations of the error box of GRB000301A
  75. GRB000301A [IPN Position]
  76. GRB000226 [IPN Position]
  77. GRB 000115 Optical observations
  78. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  79. GRB 000115, BVRI field photometry
  80. GRB000214: BeppoSAX GRBM and WFC Detection
  81. IPN annulus for GRB000214
  82. GRB000210 X-ray afterglow
  83. GRB 000210: BATSE Observations
  84. Optical observations of the Chandra X-ray source for GRB000210
  85. Optical candidate for GRB000210
  86. IPN triangulation of GRB000210
  87. GRB000210: BeppoSAX GRBM and WFC Detection
  88. GRB 000201: TAROT optical observations
  89. GRB 000131 Optical Observations
  90. GRB 991208, radio observations
  91. BATSE+IPN location of GRB000131
  92. IPN localization of GRB000131
  93. GRB 000126, optical observations
  94. BATSE location of GRB000126
  95. IPN localization of GRB000126
  96. GRB 000115 Optical observations
  97. BATSE Observations of GRB000115
  98. IPN annulus for GRB000115
  99. GRB991216, UBVRIJHK field photometry
  100. GRB991216 late optical observation

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