Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
New! Super-Kamiokande JSON Notices and Schema v4.5.0. See news and announcements

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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

879 results found.

  1. VLA Upper Limit on Outburst of SGR 1806-20
  2. GRB060806 is similar to previous activity of SGR1806-20
  3. BAT Trigger #214277 is SGR 1900+14
  4. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  5. SGR 1900+14: Swift detection of an outburst
  6. SGR 1900+14: BAT observations
  7. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  8. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  9. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  10. SGR 1900+14: Swift-BAT detection of a bright outburst
  11. SGR 1900+14: CORRECTION to GCN 4923
  12. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  13. SGR 1900+14: Swift detection of renewed activity
  14. GRB 060218: rebrightening
  15. GRB060213: Swift XRT observations and possible afterglow candidate
  16. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  17. Swift XRT Observation of GRB 060204C
  18. GRB060203: Swift XRT Team Refined Analysis
  19. An extraordinary long burst on December 3 from SGR1806-20
  20. Possible resuming of the SGR 1806-20 activity
  21. GRB050925: analysis of the XMM-Newton observation
  22. GRB/SGR 050925: XMM-Newton ToO observation
  23. GRB051103: MASTER: OT limit and host galaxy candidates
  24. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  25. SGR 1806-20: continued moderate activity seen with INTEGRAL
  26. GRB/SGR 050925: IR Observations
  27. GRB050925: Swift-BAT detection of a short burst
  28. Possible GRB 050922 detected by INTEGRAL
  29. GRB 050906: Swift-BAT refined analysis
  30. GRB 050906: Bright galaxy in BAT error box
  31. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  32. Detection of an intermediate burst from SGR 1806-20 on August 8
  33. GRB 050716: Refined XRT analysis.
  34. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  35. Konus-Wind observation of an intermediate burst from SGR 1806-20
  36. GRB 050509B: Swift/XRT refined analysis
  37. Renewal of SGR 1806-20 activity
  38. GRB 050502 - A long GRB detected with INTEGRAL
  39. Ongoing activity of SGR 1806-20 after the giant flare
  40. SGR 1806-20: GMRT results at 240 MHz band.
  41. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  42. SGR 1806-20: RXTE/PCA pulse frequency during flare
  43. SGR 1806-20: Further VLA Observations
  44. SGR 1806-20: Further low frequency GMRT results
  45. SGR 1806-20: Further VLA Observations
  46. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  47. Further VLA observations of SGR 1806-20
  48. SGR 1806-20 and extragalactic short-duration GRBs
  49. Further ATCA observations of SGR 1806-20
  50. Fourth Epoch VLA observations of SGR 1806-20
  51. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  52. SGR 1806-20: Temporal and Spectral behavior of radio transient
  53. ATCA observations of SGR 1806-20
  54. SGR 1806-20, RHESSI observations of the 041227 giant flare
  55. Third epoch observations of SGR 1806-20 with VLA
  56. Second Epoch VLA observations of SGR 1806-20
  57. Second-epoch VLA observations of SGR 1806-20
  58. SGR1806: Detection of a Sudden Ionospheric Disturbance
  59. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  60. VLA observations of SGR 1806-20
  61. SGR1806 VLA Observations
  62. VLA observations of SGR 1806-20
  63. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  64. Detection of the SGR 1806-20 giant outburst back-scattered by the
  65. The giant outburst from SGR 1806-20
  66. Giant flare from SGR 1806-20 detected by INTEGRAL
  67. Very high activity of SGR 1806-20
  68. GRB041220: Swift-BAT burst
  69. Swift-BAT detection of the bright long burst GRB041219
  70. GRB 041219 - A long GRB detected by INTEGRAL
  71. Summary of the recent bursts from SGR 1806-20
  72. IBAS GRB Alert # 2034
  73. Bright bursts from SGR1806-20
  74. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  75. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  76. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  77. SGR 1806-20 still active
  78. An intense burst from SGR1806-20
  79. Very bright burst detected from SGR 1806-20
  80. XMM-Newton Images of GRB 040827
  81. Increase of SGR 1806-20 activity
  82. Bursting activity from SGR 1806-20 detected with IBAS
  83. Ongoing activity of SGR 1806-20
  84. XRF040701: Second-Epoch Chandra Observations
  85. XRF040701: First-Epoch Chandra Observations
  86. GRB040706:observation at University of Miyazaki
  87. SGR 1806-20: no IR variability of the proposed counterparts
  88. SGR 1806-20, potential NIR counterpart
  89. Activivty of SGR 1806-20
  90. IBAS GRB Alerts n.1785 to 1791
  91. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  92. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  93. IBAS GRB Alert 1694
  94. IBAS GRB alerts 1679, 1680, 1681
  95. IBAS results on a burst from SGR1806-20
  96. IBAS alert 1180 refers to a burst from SGR 1806-20
  97. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  98. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  99. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  100. A burst from SGR 1806-20 detected with IBAS

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov