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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').

10636 results found.

  1. GRB020331 optical observations with RIMOTS
  2. GRB020124 optical observations with RIBOTS/RIMOTS
  3. GRB 020321: Candidate X-ray Counterparts
  4. GRB020406(?), optical observations
  5. GRB 020331, NIR observations
  6. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  7. GRB 020321: Optical observations
  8. GRB020317: optical observations
  9. GRB 020317 : KISO Optical Observations
  10. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  11. GRB 020317: Optical observations
  12. GRB020305: Properties of the Candidate Optical Afterglow
  13. GRB011130 (XRF011130) Second Epoch Chandra Observations
  14. GRB020305, optical observations
  15. GRB 020305: Optical observations
  16. GRB 010921: HST Observations
  17. IPN detection and localization of Cygnus X-1 flares
  18. RXTE Observations of SGR 1900+14
  19. SGR1900+14 activity
  20. IPN/HETE Detection of Bursts from SGR1900+14
  21. IPN Upper Limits to a GRB Associated With SN2002ap
  22. SN2002ap (SN/GRB?) optical spectrographic observations
  23. IPN detection of further activity from SGR1806-20
  24. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  25. IPN observations of SGR1806-20
  26. GRB 020124: Optical afterglow
  27. Possible optical counterpart to a GRB
  28. GRB011212, Optical Observations
  29. GRB011212: Optical observations at Gunma
  30. GRB011212: Optical observations
  31. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  32. GRB001109, Radio Monitoring
  33. GRB011121: fainter still
  34. GRB011121: fading behavior
  35. GRB 011030: TNG K-band observation
  36. XRF011030: Chandra Observations
  37. GRB 011030 I-band Observation
  38. The X-ray Flash 011030 ('GRB 011030')
  39. The Radio Afterglow from the X-ray Rich GRB 011030
  40. GRB 011019 optical observation
  41. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  42. GRB011019: Subaru Optical Observations
  43. GRB 011030 K-band Observations
  44. GRB011019: ROTSE-III optical observations
  45. GRB010921: Spectroscopy of the Host Galaxy
  46. GRB010928(=H1770): Localization of a Long GRB by HETE
  47. GRB001109, Host Galaxy Spectroscopic Observations
  48. Probable SGR or Short Duration GRB Detected by HETE
  49. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  50. IPN triangulation of GRB010629
  51. GRB010629: A Burst Localized by HETE
  52. SGR1900+14: Second Burst Localized by HETE
  53. Possible burst from SGR1806-20
  54. IPN detection of SGR1900+14
  55. SGR1806-20: A Second, Intense Burst Localized by HETE
  56. SGR1806-20: Localization by HETE
  57. X-ray precursors to the large flare from SGR 1900+14
  58. GRB010427, Gamma Ray Observations
  59. SGR 1900+14: No evidence of extended X-ray emission
  60. SGR 1900+14 : RXTE observations
  61. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  62. SGR1900+14
  63. SGR 1900+14: Correction to GCN 1049
  64. Millimeter observation of SGR 1900+14
  65. SGR 1900+14: Detection of extended X-ray emission
  66. Chandra Observations of SGR 1900+14
  67. SGR 1900+14, Chandra observations
  68. Chandra Observations of SGR 1900+14
  69. SGR1900+14, I-band observations
  70. GRB010326: Localization by HETE
  71. GRB010214, field photometry
  72. GRB010222, field photometry
  73. GRB010214B,Gamma Ray Observations
  74. BeppoSAX ALERT: GRB010220
  75. GRB010214: BeppoSAX WFC and GRBM preliminary data
  76. GRB 010214, Optical Observations
  77. J-Band Observation of GRB 010214.
  78. Possible InfraRed Transient of GRB 010214.
  79. GRB010214 Optical Observation
  80. GRB 010214, optical observations
  81. HETE Status
  82. GRB010126 opt. obs.
  83. IPN/RXTE TRIANGULATION OF GRB010126
  84. GRB010126 optical observations
  85. IPN/RXTE TRIANGULATION OF GRB010126
  86. IPN TRIANGULATION OF GRB010115
  87. IPN triangulation of GRB001219
  88. GRB 001212 optical observation
  89. IPN triangulation of GRB001120
  90. GRB 001109 X-ray afterglow with BeppoSAX
  91. GRB001109: Optical observations
  92. GRB001109: BeppoSAX/NFI Observations
  93. XMM-Newton observation of GRB001025
  94. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  95. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  96. ASM Localization of GRB 001025
  97. GRB001018, Gamma Ray Observations
  98. IPN TRIANGULATION OF GRB001019
  99. GRB 000926 Chandra Observation
  100. IPN triangulation of GRB 001004

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