Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

618 results found.

  1. Further VLA observations of SGR 1806-20
  2. SGR 1806-20 and extragalactic short-duration GRBs
  3. Further ATCA observations of SGR 1806-20
  4. Fourth Epoch VLA observations of SGR 1806-20
  5. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  6. SGR 1806-20: Temporal and Spectral behavior of radio transient
  7. ATCA observations of SGR 1806-20
  8. SGR 1806-20, RHESSI observations of the 041227 giant flare
  9. Third epoch observations of SGR 1806-20 with VLA
  10. Second Epoch VLA observations of SGR 1806-20
  11. Second-epoch VLA observations of SGR 1806-20
  12. SGR1806: Detection of a Sudden Ionospheric Disturbance
  13. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  14. VLA observations of SGR 1806-20
  15. SGR1806 VLA Observations
  16. VLA observations of SGR 1806-20
  17. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  18. Detection of the SGR 1806-20 giant outburst back-scattered by the
  19. The giant outburst from SGR 1806-20
  20. Giant flare from SGR 1806-20 detected by INTEGRAL
  21. Very high activity of SGR 1806-20
  22. Summary of the recent bursts from SGR 1806-20
  23. IBAS GRB Alert # 2034
  24. Bright bursts from SGR1806-20
  25. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  26. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  27. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  28. SGR 1806-20 still active
  29. An intense burst from SGR1806-20
  30. Very bright burst detected from SGR 1806-20
  31. Increase of SGR 1806-20 activity
  32. Bursting activity from SGR 1806-20 detected with IBAS
  33. Ongoing activity of SGR 1806-20
  34. GRB040706:observation at University of Miyazaki
  35. SGR 1806-20: no IR variability of the proposed counterparts
  36. SGR 1806-20, potential NIR counterpart
  37. Activivty of SGR 1806-20
  38. IBAS GRB Alerts n.1785 to 1791
  39. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  40. IBAS GRB Alert 1694
  41. IBAS GRB alerts 1679, 1680, 1681
  42. IBAS results on a burst from SGR1806-20
  43. IBAS alert 1180 refers to a burst from SGR 1806-20
  44. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  45. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  46. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  47. A burst from SGR 1806-20 detected with IBAS
  48. IPN triangulation of GRB030926 (short/hard; large error box)
  49. IBAS detection of bursts from SGR 1806-20
  50. Radio Observations of SGR1806-20
  51. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  52. Summary of recent IPN and HETE detections of SGR bursts
  53. Clarification of GCN 2354 on SGR1806-20
  54. IPN detection of continued activity from SGR1806-20
  55. 030813 SGR event (Konus-Wind observation)
  56. SGR 1808-20 (=H2802): A Possible new SGR
  57. SGR 1806-20, submm observations
  58. RXTE PCA Observations of SGR1806-20 Region
  59. HETE detection of burst from SGR1806-20
  60. GRB030329 observed as a sudden ionospheric disturbance (SID)
  61. IPN triangulation of GRB021219
  62. IPN detection of continued activity from SGR1806-20
  63. IPN detection of renewed activity from SGR1806-20
  64. IPN detection of continued SGR1900+14 activity
  65. IPN confirmation of the reactivation of SGR1900+14
  66. IPN detection of possible reactivation of SGR1900+14
  67. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  68. SGR1900+14 activity, November 2-4, 2002
  69. Detection of activity from SGR 1900+14 with the RXTE/PCA
  70. IPN detection of a burst from SGR1900+14
  71. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  72. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  73. AXP 1E2259+586: quasi-simultaneous optical observation
  74. AXP 1E2259+586 optical observations
  75. SGR-like Bursts from the AXP 1E 2259+586
  76. IPN detection of possible bursts from SGR1806-20
  77. XRF 020427: Sudden Ionospheric Disturbance (SID)
  78. Mars Odyssey joins the IPN
  79. IPN detection and localization of Cygnus X-1 flares
  80. RXTE Observations of SGR 1900+14
  81. SGR1900+14 activity
  82. IPN/HETE Detection of Bursts from SGR1900+14
  83. IPN detection of further activity from SGR1806-20
  84. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  85. Probable SGR or Short Duration GRB Detected by HETE
  86. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  87. Possible burst from SGR1806-20
  88. IPN detection of SGR1900+14
  89. X-ray precursors to the large flare from SGR 1900+14
  90. SGR 1900+14: No evidence of extended X-ray emission
  91. SGR 1900+14 : RXTE observations
  92. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  93. SGR1900+14
  94. SGR 1900+14: Correction to GCN 1049
  95. Millimeter observation of SGR 1900+14
  96. SGR 1900+14: Detection of extended X-ray emission
  97. Chandra Observations of SGR 1900+14
  98. SGR 1900+14, Chandra observations
  99. Chandra Observations of SGR 1900+14
  100. SGR1900+14, I-band observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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