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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. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  2. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  3. Detection of the SGR 1806-20 giant outburst back-scattered by the
  4. The giant outburst from SGR 1806-20
  5. IPN localization of giant flare from SGR1806-20
  6. Giant flare from SGR 1806-20 detected by INTEGRAL
  7. NIR Observations of GRB 041219
  8. GRB041226: ROTSE-III Optical Observations
  9. GRB041226: Swift-BAT detection of a burst
  10. GRB041224: ROTSE-III Optical Observations
  11. GRB041224: Swift-BAT detection of a soft burst
  12. GRB 041223: Detection of Optical Transient with LCO40
  13. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  14. GRB041223: ROTSE-III Optical Observations
  15. Very high activity of SGR 1806-20
  16. GRB 041219: WSRT Radio Afterglow Detection
  17. GRB 041219 : optical follow-up observations
  18. GRB041219c: Third Burst in One Day from Swift-BAT
  19. GRB041219: Optical Afterglow Detection
  20. GRB041218: optical observations
  21. GRB041219: P60 Optical Observations
  22. GRB 041219 - A long GRB detected by INTEGRAL
  23. GRB 041218; optical candidate
  24. GRB 041218: Optical observations
  25. GRB 041218 - A long GRB detected by integral
  26. GRB041217: The First GRB Located On-Board Swift
  27. GRB041211: Continued P60 Observations
  28. GRB 041211: Infrared Observations
  29. GRB 041211: KAIT observations
  30. GRB 041211: Optical follow-up in East Asian region
  31. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  32. GRB041015: Near-Infrared observations
  33. GRB 041006: GETS Optical Afterglow Observation
  34. Summary of the recent bursts from SGR 1806-20
  35. GRB041015, optical observation in CrAO
  36. IBAS GRB Alert # 2034
  37. Bright bursts from SGR1806-20
  38. GRB041016: MASTER: Optical observations
  39. GRB 041015 R band observations
  40. GRB041015: MASTER: Optical observations
  41. GRB041006: Fading X-ray Afterglow Observed with Chandra
  42. GRB 041015: Optical limit at Osaka University
  43. GRB 041015 - A long GRB detected by INTEGRAL
  44. GRB041006, optical observation in CrAO
  45. Search for SN light in XRF 040912 with MEGACAM
  46. GRB 041006 : optical follow-up observation at Lulin Observatory
  47. ROTSE-IIIa Observations of GRB 041006
  48. GRB 041006: Optical decay
  49. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  50. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  51. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  52. SGR 1806-20 still active
  53. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  54. GRB040924,optical observation
  55. GRB040924, RTT150 optical observation
  56. GRB040924 : Optical candidate observations at Lulin observatory
  57. GRB 040924: RTT150 optical observations
  58. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  59. XRF040916: continuing decay of OT
  60. GRB040912(=H3557): Candidate Optical Afterglow
  61. GRB040916 optical limits 17 min after GRB
  62. XRF 040912, identification of CXO sources
  63. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  64. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  65. GRB 040912: Optical Observations
  66. An intense burst from SGR1806-20
  67. GRB040912 : Kiso Optical follow-up observation
  68. HETE 3557: Optical observations
  69. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  70. GRB040903 - A XRF?
  71. GRB040827: analysis of the XMM-Newton observation
  72. Very bright burst detected from SGR 1806-20
  73. Possible GRB 040903 - further analysis
  74. GRB 040827 : peak flux
  75. Increase of SGR 1806-20 activity
  76. GRB 040812: Optical counterparts of CXO sources
  77. Bursting activity from SGR 1806-20 detected with IBAS
  78. Konus-Wind observation of GRB040810 (=H3489)
  79. GRB 040812: a long GRB detected by INTEGRAL
  80. GRB 040730: Optical observations
  81. GRB 040730: a long GRB detected with INTEGRAL
  82. Ongoing activity of SGR 1806-20
  83. XRF 040701 - optical observations of the decaying Chandra source
  84. XRF040701: Second-Epoch Chandra Observations
  85. Cancellation of IBAS/INTEGRAL GRB alerts
  86. XRF040701: VLA Observations
  87. XRF040701: First-Epoch Chandra Observations
  88. GRB040709 J,H-band observations
  89. GRB040706:observation at University of Miyazaki
  90. GRB 040624: optical observations
  91. GRB 040624: R-band observations
  92. GRB 040624 - A long GRB detected with INTEGRAL
  93. IPN Summary of SGR1806-20 Activity in 2004
  94. SGR 1806-20: no IR variability of the proposed counterparts
  95. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  96. SGR 1806-20, potential NIR counterpart
  97. MASTER: HETE Alert 3274 optical observation
  98. Activivty of SGR 1806-20
  99. IPN triangulation of an intense intermediate burst from SGR1806-20
  100. IBAS GRB Alerts n.1785 to 1791

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