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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').

9654 results found.

  1. GRB020525, optical observations
  2. IPN detection of possible bursts from SGR1806-20
  3. IPN triangulation of GRB020525
  4. XRF 020427: Sudden Ionospheric Disturbance (SID)
  5. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  6. IPN triangulation of a burst from SGR1806-20
  7. GRB 020410, Radio Observations
  8. GRB 020124: Optical observations
  9. IPN triangulation of GRB020418
  10. GRB020410: BeppoSAX NFI observations refined analysis
  11. Mars Odyssey joins the IPN
  12. IPN triangulation of GRB020413
  13. GRB 020409 SARA Observations
  14. GRB 020409, No Optical Detection to R = 20
  15. GRB020410: BeppoSAX NFI observation
  16. GRB 020409, optical observations
  17. GRB020406(?), optical observations
  18. BeppoSAX ALERT: possible GRB020410
  19. GRB020331 optical observations with RIMOTS
  20. GRB020124 optical observations with RIBOTS/RIMOTS
  21. GRB 020321: Candidate X-ray Counterparts
  22. GRB020406(?), optical observations
  23. GRB 020331, NIR observations
  24. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  25. GRB 020321: Optical observations
  26. GRB020317: optical observations
  27. GRB 020317 : KISO Optical Observations
  28. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  29. GRB 020317: Optical observations
  30. GRB020305: Properties of the Candidate Optical Afterglow
  31. GRB011130 (XRF011130) Second Epoch Chandra Observations
  32. GRB020305, optical observations
  33. GRB 020305: Optical observations
  34. GRB 010921: HST Observations
  35. IPN detection and localization of Cygnus X-1 flares
  36. RXTE Observations of SGR 1900+14
  37. SGR1900+14 activity
  38. IPN/HETE Detection of Bursts from SGR1900+14
  39. IPN Upper Limits to a GRB Associated With SN2002ap
  40. SN2002ap (SN/GRB?) optical spectrographic observations
  41. IPN detection of further activity from SGR1806-20
  42. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  43. IPN observations of SGR1806-20
  44. GRB 020124: Optical afterglow
  45. Possible optical counterpart to a GRB
  46. GRB011212, Optical Observations
  47. GRB011212: Optical observations at Gunma
  48. GRB011212: Optical observations
  49. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  50. GRB001109, Radio Monitoring
  51. GRB011121: fainter still
  52. GRB011121: fading behavior
  53. GRB 011030: TNG K-band observation
  54. XRF011030: Chandra Observations
  55. GRB 011030 I-band Observation
  56. The X-ray Flash 011030 ('GRB 011030')
  57. The Radio Afterglow from the X-ray Rich GRB 011030
  58. GRB 011019 optical observation
  59. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  60. GRB011019: Subaru Optical Observations
  61. GRB 011030 K-band Observations
  62. GRB011019: ROTSE-III optical observations
  63. GRB010921: Spectroscopy of the Host Galaxy
  64. GRB010928(=H1770): Localization of a Long GRB by HETE
  65. GRB001109, Host Galaxy Spectroscopic Observations
  66. Probable SGR or Short Duration GRB Detected by HETE
  67. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  68. IPN triangulation of GRB010629
  69. GRB010629: A Burst Localized by HETE
  70. SGR1900+14: Second Burst Localized by HETE
  71. Possible burst from SGR1806-20
  72. IPN detection of SGR1900+14
  73. SGR1806-20: A Second, Intense Burst Localized by HETE
  74. SGR1806-20: Localization by HETE
  75. X-ray precursors to the large flare from SGR 1900+14
  76. GRB010427, Gamma Ray Observations
  77. SGR 1900+14: No evidence of extended X-ray emission
  78. SGR 1900+14 : RXTE observations
  79. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  80. SGR1900+14
  81. SGR 1900+14: Correction to GCN 1049
  82. Millimeter observation of SGR 1900+14
  83. SGR 1900+14: Detection of extended X-ray emission
  84. Chandra Observations of SGR 1900+14
  85. SGR 1900+14, Chandra observations
  86. Chandra Observations of SGR 1900+14
  87. SGR1900+14, I-band observations
  88. GRB010326: Localization by HETE
  89. GRB010214, field photometry
  90. GRB010222, field photometry
  91. GRB010214B,Gamma Ray Observations
  92. BeppoSAX ALERT: GRB010220
  93. GRB010214: BeppoSAX WFC and GRBM preliminary data
  94. GRB 010214, Optical Observations
  95. J-Band Observation of GRB 010214.
  96. Possible InfraRed Transient of GRB 010214.
  97. GRB010214 Optical Observation
  98. GRB 010214, optical observations
  99. HETE Status
  100. GRB010126 opt. obs.

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