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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').

19114 results found.

  1. GRB 010222 - WHT BVRI images
  2. GRB 010629 Optical Observations
  3. SGR1900+14: High Fluence Burst Localized by HETE
  4. GRB010629, optical observations
  5. IPN triangulation of GRB010629
  6. GRB010629: A Burst Localized by HETE
  7. SGR1900+14: Second Burst Localized by HETE
  8. SGR1900+14: A Burst Localized by HETE
  9. SGR1806-20: A Second, Intense Burst Localized by HETE
  10. SGR1806-20: Localization by HETE
  11. HETE Fully-Automated GCN Notices
  12. GRB000301C: Late-time HST/STIS observation
  13. GRB010518: a faint BeppoSAX detection
  14. GRB000418: HST/STIS Second-epoch Observations
  15. X-ray precursors to the large flare from SGR 1900+14
  16. GRB010427, Gamma Ray Observations
  17. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  18. SGR 1900+14: Correction to GCN 1049
  19. Millimeter observation of SGR 1900+14
  20. SGR 1900+14: Detection of extended X-ray emission
  21. SGR 1900+14, Chandra observations
  22. Possible precursor to the SGR1900+14 giant burst
  23. SGR1900+14, I-band observations
  24. IPN Triangulation of the Giant Flare from SGR1900+14
  25. GRB010412, field photometry
  26. Giant flare from SGR1900+14
  27. GRB 010326b Optical Observations
  28. GRB010412: BeppoSAX GRBM and WFC observations
  29. GRB010324, revised field photometry
  30. REVISED LOCATION OF GRB010326A
  31. GRB 980326: Late-time HST/STIS observations
  32. GRB010324, field photometry
  33. GRB010326B, field photometry
  34. GRB010326, field photometry
  35. GRB010220, field photometry
  36. Further Optical Observations of GRB 010324
  37. GRB010222, CXO X-ray observations
  38. GRB010324, optical observations
  39. GRB010326B: Localization by HETE (2nd GRB for this date)
  40. GRB 010326 optical observations
  41. GRB010326: Refined Localization by HETE
  42. GRB010326: Localization by HETE
  43. Optical Observations of GRB 010324
  44. GRB010222, late-time optical observation
  45. Support extension to the BeppoSAX mission
  46. GRB 010222, Optical Observations
  47. GRB 010222: High-Resolution Keck Spectroscopy
  48. GRB010222 further R-band photometry
  49. GRB 010222: Keck Spectroscopy
  50. GRB010214, field photometry
  51. GRB010222, field photometry
  52. GRB010222 further R-band photometry
  53. GRB 010222 Kyoto optical observation
  54. GRB010222 R-BAND OBSERVATION
  55. GRB010214 follow-up from Hanle
  56. GRB 010222: Near-IR Observations
  57. GRB 010222: Optical Observations
  58. GRB010222, radio observations
  59. GRB010222, optical observations
  60. GRB010214B,Gamma Ray Observations
  61. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  62. GRB 010220, simultaneous optical observations
  63. GRB010220: BeppoSAX WFC and GRBM preliminary data
  64. GRB010214, optical observations
  65. GRB010214: BeppoSAX WFC and GRBM preliminary data
  66. GRB 010214: X-Ray afterglow
  67. GRB 010214 optical observation
  68. GRB010213, Radio Observations
  69. J-Band Observation of GRB 010214.
  70. GRB010214, Radio Observations
  71. GRB010213, Near-IR observations
  72. Possible InfraRed Transient of GRB 010214.
  73. GRB010213 (HETE) TAROT observations
  74. GRB010213 detected by HETE
  75. BeppoSAX ALERT: GRB010214
  76. HETE Status
  77. IPN/RXTE TRIANGULATION OF GRB010126
  78. GRB010126 optical observations
  79. IPN/RXTE TRIANGULATION OF GRB010126
  80. Optical Observations of GRB 001018 at Keck
  81. GRB010119, Radio observations
  82. Optical observations of GRB 001018 with JCAM
  83. IPN TRIANGULATION OF GRB010115
  84. IPN TRIANGULATION OF GRB010109
  85. IPN triangulation of GRB010103
  86. GRB 001204: Ks observations
  87. GRB 001212 Optical Observation
  88. GRB 001212 Optical Observation
  89. GRB001204, Radio observations
  90. IPN triangulation of GRB001204 (short/hard)
  91. GRB001120: Gunn-i observations
  92. GRB001120, optical observations
  93. WSRT 4.8 GHz observations of GRB001109
  94. IPN triangulation of GRB001120
  95. GRB 001109: deep JHK upper limits
  96. GRB 001109 X-ray afterglow with BeppoSAX
  97. CORRECTION to XMM-Newton observation of GRB001025
  98. GRB001109, Radio observations
  99. GRB001105 BVRI field photometry correction
  100. GRB001105, BVRI field photometry

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