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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').

23921 results found.

  1. GRB 000301C: HST/STIS CCD Imaging of the field
  2. IPN error box for GRB000307
  3. GRB000301C, optical R-band observations
  4. GRB 000301C Optical Observations
  5. GRB 000301C: K' Observations
  6. GRB000301C OT candidate optical observations
  7. GRB000301C - Host galaxy not detected in R (?)
  8. Optical observations of GRB000301c
  9. GRB000301C, Radio observations
  10. GRB000301C, Radio observations
  11. GRB000301C, near-infrared observations (JHK' imaging)
  12. GRB 000301c near-IR observations
  13. GRB 000301C, UBVRI field photometry
  14. GRB 000301C: OT confirmed
  15. GRB000301c optical observations
  16. GRB000301C, optical observations
  17. GRB000301C
  18. GRB 000301C : Optical Candidate
  19. GRB000301C: RXTE/ASM and IPN localizations
  20. GRB000226 [IPN Position]
  21. HST Observations of GRB 990712
  22. GRB 000214 near-IR observations
  23. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  24. GRB000210, Radio Observations
  25. GRB 000115, BVRI field photometry
  26. GRB000214: BeppoSAX GRBM and WFC Detection
  27. Optical observations of GRB000210
  28. GRB000210 X-ray afterglow
  29. GRB000214: X-ray afterglow candidate
  30. GRB000214 refined BeppoSAX-WFC position
  31. GRB 000210: BATSE Observations
  32. Optical observations of the Chandra X-ray source for GRB000210
  33. GRB000210, Radio Observations
  34. IPN triangulation of GRB000210
  35. GRB000210: possible afterglow detection with BeppoSAX NFI
  36. GRB000201, Radio Observations
  37. GRB000210: BeppoSAX GRBM and WFC Detection
  38. SAX_WFC_GRB_NOTICE
  39. SAX_WFC_GRB_NOTICE
  40. GRB000201 Optical Observations
  41. GRB 000201: TAROT optical observations
  42. GRB 991208, radio observations
  43. BATSE+IPN location of GRB000131
  44. IPN localization of GRB000131
  45. GRB 000126, optical observations
  46. BATSE Observations of GRB000115
  47. Second RXTE Observation of GRB 000115
  48. GRB991216, UBVRIJHK field photometry
  49. GCN resumes full operations
  50. GRB 991216 VLBA Observations
  51. GRB 991216: J band spectrophotometry
  52. GRB 991216: Detection of the Host and/or Absorber Galaxy
  53. IPN localization of GRB991226
  54. GRB 991216 RXTE ASM Observations
  55. GRB 991216: Updated BATSE parameters
  56. GRB 991217 (SAX J2303.2+0015) Optical observations
  57. Chandra observation of the X-ray afterglow of GRB991216
  58. GRB 991216, optical observations
  59. GRB 991216 Optical spectroscopy/imaging
  60. SAX J2303.2+0015 Optical observations
  61. IR observations of GRB991216
  62. GRB 991217 (SAX J2303.2+0015) Optical observations
  63. GRB991216 Optical and infrared observations of Beethoven Burst
  64. GRB 991216 Radio Observations
  65. GRB 991208 Keck Spectroscopy
  66. GRB 991208 Infrared Detection
  67. GRB991216
  68. GRB 991216--Summary of RXTE Observations
  69. GRB 991216 Optical Observations
  70. GRB 991216, optical observations
  71. GRB 991208 SAO-RAS Spectroscopy
  72. SAX J2303.2+0015: an x-ray/GRB?
  73. GRB 991216, Optical Transient
  74. GRB991216 ('Beethoven Burst') B, R, and K Observations
  75. GRB991216, infrared observations
  76. GRB 991208 optical observations
  77. GRB 991216 Optical Observation
  78. GRB 991216: Extremely bright BATSE burst
  79. R-band Observations of GRB991208 at TNG
  80. GRB991208, optical observations
  81. GRB 991208, Optical Observation
  82. GRB991208, optical observations
  83. GRB 991208 optical observations
  84. Optical Observations of GRB991105
  85. GRB991106: BeppoSAX/BATSE results
  86. GRB991106, near-infrared observations
  87. BeppoSAX NFI Observation of GRB991106
  88. GRB 991106, radio observations
  89. GRB991106: the first BeppoSAX short GRB detection?
  90. GRB 991105: BATSE Observations
  91. GRB 991106 Optical Observations
  92. GRB991106, optical observation at SAO-RAS
  93. GRB 991106, LOTIS Optical Observations
  94. GRB991105: SAX-GRBM/-WFC detection
  95. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  96. GRB 991014, Optical Observations
  97. GRB 991014 - BeppoSAX NFI observations
  98. GRB 991014, radio observations
  99. GRB 991014, Optical Observations
  100. GRB 991014, optical observations

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