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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 results
  2. GRB000408: Optical CCD Observations from MIRO
  3. GRB000408, lotis optical observations
  4. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  5. GRB000408 [IPN Position]
  6. GRB000326 Optical Observations
  7. GRB000301C - Addendum to GCN 623
  8. GRB000301C - R magnitude lower limit
  9. GRB000326, Further VLA observations
  10. GRB 000323, optical observations
  11. GRB 000326: Optical Observations
  12. GRB000326, Radio observations
  13. GRB000326 [IPN Position]
  14. GRB 000307 optical observations
  15. GRB000323 [IPN Position]
  16. Single error box for GRB000315
  17. GRB000315 [IPN Positions]
  18. GRB000313, Radio observations
  19. GRB 000313 - optical transient in the BATSE error box
  20. GRB000301C - B and R photometry
  21. GRB000301C - R photometry
  22. GRB 000307, Optical Observations
  23. GRB 000307, BVRI Field Photometry
  24. GRB 000301C: Optical Spectrum and Redshift
  25. GRB 000301C: Optical Spectrum and Redshift
  26. GRB 000301C: A Precise Redshift Determination
  27. GRB 000301C, Optical Observation
  28. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  29. GRB 000301C: HST/STIS CCD Imaging of the field
  30. IPN error box for GRB000307
  31. GRB 000301c: K' observations
  32. GRB000301C, optical R-band observations
  33. GRB000301c - R photometry and nearby faint source confirmation
  34. GRB 000301C, Optical Observation
  35. GRB 000301c: K' observations
  36. GRB 000301C Optical Observations
  37. GRB 000301C: K' Observations
  38. GRB000301C OT candidate optical observations
  39. GRB000301C - Host galaxy not detected in R (?)
  40. Optical observations of GRB000301c
  41. GRB000301C, Radio observations
  42. GRB000301C, Radio observations
  43. GRB000301C optical observations
  44. GRB000301C, near-infrared observations (JHK' imaging)
  45. GRB 000301c near-IR observations
  46. GRB 000301C, Optical Color
  47. GRB000301C, Optical Spectroscopy
  48. GRB 000301C, UBVRI field photometry
  49. GRB 000301C, Optical Observation
  50. GRB000301C, optical observations
  51. GRB000301C 250 GHz detection
  52. GRB 000301C R-band observation
  53. GRB 000301C, Optical Observation
  54. GRB000301C, near-infrared observations (JHK' photometry)
  55. GRB 000301C: OT confirmed
  56. GRB000301c optical observations
  57. GRB 000301A, Radio Observations
  58. GRB000301C, optical observations
  59. GRB000301c, near-infrared observations
  60. GRB000301C
  61. GRB 000301C : Optical Candidate
  62. Radio observations of the error box of GRB000301A
  63. GRB000301C: RXTE/ASM and IPN localizations
  64. GRB000301A [IPN Position]
  65. GRB000226 [IPN Position]
  66. HST Observations of GRB 990712
  67. GRB 000214 near-IR observations
  68. GRB 000115 Optical observations
  69. GRB 000214, Radio Observations
  70. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  71. GRB000210, Radio Observations
  72. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  73. GRB 000115, BVRI field photometry
  74. GRB000214: BeppoSAX GRBM and WFC Detection
  75. IPN annulus for GRB000214
  76. BATSE GRB trigger criterion changed
  77. Optical observations of GRB000210
  78. GRB000210 X-ray afterglow
  79. GRB000214: X-ray afterglow candidate
  80. GRB000214 refined BeppoSAX-WFC position
  81. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  82. GRB 000210: BATSE Observations
  83. Correction to Chandra Position of GRB000210 afterglow
  84. Optical observations of the Chandra X-ray source for GRB000210
  85. GRB000210, Radio Observations
  86. Optical candidate for GRB000210
  87. Chandra Observations of GRB000210 X-ray Afterglow
  88. IPN triangulation of GRB000210
  89. GRB000210: possible afterglow detection with BeppoSAX NFI
  90. GRB000201, Radio Observations
  91. GRB000210: BeppoSAX GRBM and WFC Detection
  92. SAX_WFC_GRB_NOTICE
  93. SAX_WFC_GRB_NOTICE
  94. Optical observations of GRB000131
  95. GRB000201 Optical Observations
  96. GRB 000201: TAROT optical observations
  97. GRB 000131 Optical Observations
  98. GRB000126 Optical Observations
  99. BATSE GRB trigger criteria changed
  100. GRB 991208, radio observations

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