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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').

18687 results found.

  1. GRB000408 [IPN Position]
  2. GRB000301C - Addendum to GCN 623
  3. GRB 000326: Optical Observations
  4. GRB000326, Radio observations
  5. GRB000315 [IPN Positions]
  6. GRB000313, Radio observations
  7. GRB 000313 - optical transient in the BATSE error box
  8. GRB 000307, BVRI Field Photometry
  9. GRB 000301C: HST/STIS CCD Imaging of the field
  10. IPN error box for GRB000307
  11. GRB000301C, optical R-band observations
  12. GRB000301c - R photometry and nearby faint source confirmation
  13. GRB 000301C Optical Observations
  14. GRB 000301C: K' Observations
  15. GRB000301C - Host galaxy not detected in R (?)
  16. Optical observations of GRB000301c
  17. GRB000301C, Radio observations
  18. GRB000301C, Radio observations
  19. GRB 000301c near-IR observations
  20. GRB 000301C, UBVRI field photometry
  21. GRB000301C, near-infrared observations (JHK' photometry)
  22. GRB 000301C: OT confirmed
  23. GRB000301c optical observations
  24. GRB000301c, near-infrared observations
  25. GRB000301C
  26. GRB 000301C : Optical Candidate
  27. GRB000301C: RXTE/ASM and IPN localizations
  28. GRB000226 [IPN Position]
  29. HST Observations of GRB 990712
  30. GRB 000214 near-IR observations
  31. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  32. GRB000210, Radio Observations
  33. GRB 000115, BVRI field photometry
  34. GRB000214: BeppoSAX GRBM and WFC Detection
  35. Optical observations of GRB000210
  36. GRB000210 X-ray afterglow
  37. GRB000214: X-ray afterglow candidate
  38. GRB000214 refined BeppoSAX-WFC position
  39. GRB 000210: BATSE Observations
  40. Optical observations of the Chandra X-ray source for GRB000210
  41. GRB000210, Radio Observations
  42. GRB000201, Radio Observations
  43. GRB000210: BeppoSAX GRBM and WFC Detection
  44. Optical observations of GRB000131
  45. GRB000201 Optical Observations
  46. GRB 000201: TAROT optical observations
  47. IPN localization of GRB000131
  48. GRB 000126, optical observations
  49. IPN localization of GRB000126
  50. BATSE Observations of GRB000115
  51. GRB991216, UBVRIJHK field photometry
  52. GCN resumes full operations
  53. IPN error boxes for GRB991229
  54. GRB 991216: Detection of the Host and/or Absorber Galaxy
  55. IPN error boxes for GRB991221
  56. IPN error box for GRB991216
  57. GRB 991217 (SAX J2303.2+0015) Optical observations
  58. Chandra observation of the X-ray afterglow of GRB991216
  59. GRB 991216, optical observations
  60. GRB 991216 Optical spectroscopy/imaging
  61. GRB991216 Optical and IR observations
  62. SAX J2303.2+0015 Optical observations
  63. IR observations of GRB991216
  64. GRB 991217 (SAX J2303.2+0015) Optical observations
  65. GRB991216 Optical and infrared observations of Beethoven Burst
  66. GRB 991216 Radio Observations
  67. GRB 991208 Infrared Detection
  68. GRB991216
  69. GRB 991216--Summary of RXTE Observations
  70. GRB 991216 Optical Observations
  71. GRB 991216, optical observations
  72. GRB 991208 SAO-RAS Spectroscopy
  73. SAX J2303.2+0015: an x-ray/GRB?
  74. GRB 991216, Optical Transient
  75. GRB991216 ('Beethoven Burst') B, R, and K Observations
  76. GRB991216, infrared observations
  77. GRB 991208 optical observations
  78. Lowell/Perkins observation of GRB 991216
  79. GRB 991216 Optical Observation
  80. GRB 991216: Extremely bright BATSE burst
  81. R-band Observations of GRB991208 at TNG
  82. GRB991208, optical observations
  83. GRB 991208, Optical Observation
  84. GRB991208, optical observations
  85. GRB 991208 Optical Decay
  86. Optical Observations of GRB991105
  87. GRB991106: BeppoSAX/BATSE results
  88. GRB 991106, optical observations
  89. BeppoSAX NFI Observation of GRB991106
  90. GRB 991106, radio observations
  91. GRB991106: the first BeppoSAX short GRB detection?
  92. GRB 991106 Optical Observations
  93. GRB991106, optical observation at SAO-RAS
  94. GRB 991106, LOTIS Optical Observations
  95. GRB991105: SAX-GRBM/-WFC detection
  96. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  97. GRB ALERT: GRB991105
  98. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  99. GRB 991014, Optical Observations
  100. GRB 991014 - BeppoSAX NFI observations

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