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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').

32069 results found.

  1. GRB 010222, Decay Slope Confirmed
  2. GRB010222: Another absorption line system
  3. GRB010222: Optical decay slope
  4. GRB 010214, Optical Observations
  5. GRB010222: Sub-millimeter detection
  6. GRB010222: R-band fading behavior
  7. GRB010222: Optical Observations
  8. GRB010222, optical observations
  9. GRB010222: BeppoSAX/NFI Observations
  10. Redshift of the Optical Transient of GRB010222
  11. GRB010214B,Gamma Ray Observations
  12. GRB010222
  13. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  14. GRB 010220, simultaneous optical observations
  15. GRB010220: BeppoSAX WFC and GRBM preliminary data
  16. BeppoSAX ALERT: GRB010220
  17. GRB010214: BeppoSAX WFC and GRBM preliminary data
  18. GRB 010214: X-Ray afterglow
  19. GRB 010214, Optical Observations
  20. GRB 010214 optical observation
  21. GRB010213 Optical Observation
  22. J-Band Observation of GRB 010214.
  23. GRB010213, Near-IR observations
  24. Possible InfraRed Transient of GRB 010214.
  25. GRB010214 Optical Observation
  26. GRB010214: BeppoSAX/NFI Observations
  27. GRB010213 (HETE) TAROT observations
  28. GRB 010214, optical observations
  29. BeppoSAX ALERT: GRB010214
  30. IPN Status Report
  31. HETE Status
  32. GRB010126 opt. obs.
  33. IPN/RXTE TRIANGULATION OF GRB010126
  34. GRB010126: CONCAM crude optical limits during GRB
  35. GRB010126, TNG R-band observations
  36. IPN TRIANGULATION OF GRB010126
  37. IPN/RXTE TRIANGULATION OF GRB010126
  38. GRB 010119, optical observations
  39. GRB010119: Optical observations
  40. Optical Observations of GRB 001018 at Keck
  41. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  42. Optical observations of GRB 001018 with JCAM
  43. IPN TRIANGULATION OF GRB010115
  44. IPN TRIANGULATION OF GRB010109
  45. GRB010103, optical observations
  46. IPN triangulation of GRB010104
  47. IPN triangulation of GRB010103
  48. GRB 001204: Ks observations
  49. H band observation of GRB 001212
  50. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  51. IPN triangulation of GRB001219
  52. GRB 001212 Optical Observation
  53. GRB 001212 Optical Observation
  54. GRB 001212 optical observation
  55. GRB 001212 possible OA in 2MASS
  56. GRB 001212 possible OA
  57. IPN triangulation of GRB001212
  58. Confirmation of IPN position for GRB001204
  59. IPN triangulation of GRB001204 (short/hard)
  60. GRB 001105, further optical observations
  61. GRB001120: Gunn-i observations
  62. GRB001120: Optical observations
  63. GRB001109, optical observations
  64. GRB001120, optical observations
  65. IPN triangulation of GRB001120
  66. Optical/NIR observations of GRB001109
  67. GRB 001109: deep JHK upper limits
  68. GRB 001109 X-ray afterglow with BeppoSAX
  69. GRB001109: Optical observations
  70. GRB001109: BeppoSAX/NFI Observations
  71. GRB001109, R-band optical observations
  72. GRB001109, Radio observations
  73. BeppoSAX ALERT: GRB001109
  74. GRB001105 BVRI field photometry correction
  75. GRB001105, BVRI field photometry
  76. GRB 001105, R-band observation
  77. IPN TRIANGULATION OF GRB001105
  78. GRB 001025B, Optical obervations
  79. GRB 991208: HST Imaging of the Host Galaxy
  80. GRB000926: R-image of the host galaxy
  81. GRB 001025B, I-band observations
  82. GRB 001025 Optical Observations
  83. GRB 001025A, optical observation
  84. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  85. IPN triangulation of GRB001025
  86. ASM Localization of GRB 001025
  87. GRB001007, Radio observations
  88. IPN TRIANGULATION OF GRB001020
  89. GRB001019, Optical Observations
  90. GRB 001018, Possible Radio Afterglow
  91. GRB001018, Gamma Ray Observations
  92. IPN TRIANGULATION OF GRB001019
  93. IPN TRIANGULATION OF GRB001018
  94. IPN TRIANGULATION OF GRB 001017
  95. GRB 000926: Improved Absorber Redshift
  96. V,R,I band observations of GRB000926
  97. The Likely Optical/Infrared Afterglow of GRB 001011
  98. HETE positions added to GCN
  99. BeppoSAX ALERT: GRB001011
  100. GRB 001007, BVR-band observations

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