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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').
  1. GRB000301C - R magnitude lower limit
  2. GRB000326, Further VLA observations
  3. GRB 000323, optical observations
  4. GRB 000326: Optical Observations
  5. GRB000326, Radio observations
  6. GRB000326 [IPN Position]
  7. GRB 000307 optical observations
  8. GRB000323 [IPN Position]
  9. Single error box for GRB000315
  10. GRB000315 [IPN Positions]
  11. GRB000313, Radio observations
  12. GRB 000313 - optical transient in the BATSE error box
  13. GRB000301C - B and R photometry
  14. GRB000301C - R photometry
  15. GRB 000307, Optical Observations
  16. GRB 000307, BVRI Field Photometry
  17. GRB 000301C: Optical Spectrum and Redshift
  18. GRB 000301C: Optical Spectrum and Redshift
  19. GRB 000301C: A Precise Redshift Determination
  20. GRB 000301C, Optical Observation
  21. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  22. GRB 000301C: HST/STIS CCD Imaging of the field
  23. IPN error box for GRB000307
  24. GRB 000301c: K' observations
  25. GRB000301C, optical R-band observations
  26. GRB000301c - R photometry and nearby faint source confirmation
  27. GRB 000301C, Optical Observation
  28. GRB 000301c: K' observations
  29. GRB 000301C Optical Observations
  30. GRB 000301C: K' Observations
  31. GRB000301C OT candidate optical observations
  32. GRB000301C - Host galaxy not detected in R (?)
  33. Optical observations of GRB000301c
  34. GRB000301C, Radio observations
  35. GRB000301C, Radio observations
  36. GRB000301C optical observations
  37. GRB000301C, near-infrared observations (JHK' imaging)
  38. GRB 000301c near-IR observations
  39. GRB 000301C, Optical Color
  40. GRB000301C, Optical Spectroscopy
  41. GRB 000301C, UBVRI field photometry
  42. GRB 000301C, Optical Observation
  43. GRB000301C, optical observations
  44. GRB000301C 250 GHz detection
  45. GRB 000301C R-band observation
  46. GRB 000301C, Optical Observation
  47. GRB000301C, near-infrared observations (JHK' photometry)
  48. GRB 000301C: OT confirmed
  49. GRB000301c optical observations
  50. GRB 000301A, Radio Observations
  51. GRB000301C, optical observations
  52. GRB000301c, near-infrared observations
  53. GRB000301C
  54. GRB 000301C : Optical Candidate
  55. Radio observations of the error box of GRB000301A
  56. GRB000301C: RXTE/ASM and IPN localizations
  57. GRB000301A [IPN Position]
  58. GRB000226 [IPN Position]
  59. HST Observations of GRB 990712
  60. GRB 000214 near-IR observations
  61. GRB 000115 Optical observations
  62. GRB 000214, Radio Observations
  63. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  64. GRB000210, Radio Observations
  65. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  66. GRB 000115, BVRI field photometry
  67. GRB000214: BeppoSAX GRBM and WFC Detection
  68. IPN annulus for GRB000214
  69. BATSE GRB trigger criterion changed
  70. Optical observations of GRB000210
  71. GRB000210 X-ray afterglow
  72. GRB000214: X-ray afterglow candidate
  73. GRB000214 refined BeppoSAX-WFC position
  74. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  75. GRB 000210: BATSE Observations
  76. Correction to Chandra Position of GRB000210 afterglow
  77. Optical observations of the Chandra X-ray source for GRB000210
  78. GRB000210, Radio Observations
  79. Optical candidate for GRB000210
  80. Chandra Observations of GRB000210 X-ray Afterglow
  81. IPN triangulation of GRB000210
  82. GRB000210: possible afterglow detection with BeppoSAX NFI
  83. GRB000201, Radio Observations
  84. GRB000210: BeppoSAX GRBM and WFC Detection
  85. SAX_WFC_GRB_NOTICE
  86. SAX_WFC_GRB_NOTICE
  87. Optical observations of GRB000131
  88. GRB000201 Optical Observations
  89. GRB 000201: TAROT optical observations
  90. GRB 000131 Optical Observations
  91. GRB000126 Optical Observations
  92. BATSE GRB trigger criteria changed
  93. GRB 991208, radio observations
  94. BATSE+IPN location of GRB000131
  95. IPN localization of GRB000131
  96. GRB 000126, optical observations
  97. GRB000126, optical observations
  98. BATSE location of GRB000126
  99. IPN localization of GRB000126
  100. GRB 000115 Optical observations

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