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"

28056 results found.

  1. GRB041006: MASTER optical observations
  2. GRB041006,optical observation
  3. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  4. GRB041006: Fading of optical afterglow candidate
  5. GRB 041006: Optical afterglow candidate
  6. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  7. XRF 020903: Observations of the Host Galaxy
  8. radio observations, GRB 040924
  9. GRB040929,optical observation
  10. GRB040924,optical observation
  11. GRB040924,optical observation
  12. GRB 040924: detection of possible host galaxy by Subaru
  13. GRB040924: KAIT observations
  14. GRB040924 : Optical candidate observations at Lulin observatory
  15. GRB040924 : Optical candidate observations at Lulin observatory
  16. GRB 040924: Subaru NIR observation
  17. XRF 040912: Radio Observations
  18. XRF 040916: Radio Observations
  19. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  20. XRF040916: continuing decay of OT
  21. TAROT Observations of GRB 040916 (HETE #3558)
  22. GRB040912(=H3557): Candidate Optical Afterglow
  23. XRF040916, optical observations
  24. XRF 040912, identification of CXO sources
  25. XRF040912, BVRcIc field calibration
  26. XRF040916, BVRcIc field calibration
  27. GRB040916: Archival optical observations
  28. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  29. GRB040916: Optical observations
  30. GRB040912 (= H3557): Chandra Observations Scheduled
  31. GRB 040912: Optical Observations
  32. GRB/XRF040912,optical observations
  33. GRB 040912, BVRI observations
  34. Optical observations of field of GRB040912
  35. HETE 3557: Optical observations
  36. GRB040903 - A XRF?
  37. GRB040827: analysis of the XMM-Newton observation
  38. GRB040903, REM near-IR observation
  39. Very bright burst detected from SGR 1806-20
  40. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  41. Possible GRB 040903 - further analysis
  42. GRB 040827 - Radio Observations
  43. XMM-Newton Images of GRB 040827
  44. GRB 040827: optical and NIR observations at the VLT
  45. GRB 040827: UKIRT - 2nd epoch K-band imaging
  46. GRB 040827: 2nd epoch of Magellan K-band imaging
  47. GRB 040827: K imaging - no evidence of variability
  48. GRB 040827: Detection of NIR afterglow
  49. GRB040827 XMM-Newton observation
  50. GRB040825A: optical limit before GRB
  51. GRB 040825B: Optical observations
  52. GRB 040827 : Planned XMM-Newton observation
  53. GRB040825B, BVRcIc field photometry
  54. GRB040825A, BVRcIc field photometry
  55. GCN GRB OBSERBATION REPORT
  56. GRB 040825A,optical observations
  57. GRB040825A: optical observations
  58. GRB040825B: optical observations
  59. MASTER: GRB040825b optical observation
  60. GRB 040825: Optical observations
  61. XRF040812: possible afterglow second Chandra observation
  62. GRB 040812: Second epoch CXO Observations
  63. GRB040823,optical observation
  64. XRF040812: GMRT observations
  65. XRF 040812: optical observation at VLT
  66. GRB 040812: Optical counterparts of CXO sources
  67. XRF040812: possible afterglow
  68. CXO observation of GRB 040812
  69. GRB 040812: radio observations
  70. GRB040812, optical/IR observations
  71. GRB 040812: a long GRB detected by INTEGRAL
  72. XRF040701: Optical Observations at ESO
  73. GRB 040730, infrared observations
  74. GRB 040730: a long GRB detected with INTEGRAL
  75. Ongoing activity of SGR 1806-20
  76. GRB040624: optical monitoring at TNG
  77. XRF 040701 - optical observations of the decaying Chandra source
  78. XRF040701: Second-Epoch Chandra Observations
  79. XRF040701: VLA Observations
  80. XRF040701: First-Epoch Chandra Observations
  81. GRB040624, optical observations
  82. GRB040706:observation at University of Miyazaki
  83. Optical Observations of GRB040624
  84. GRB 040624: optical observations at TNG and VLT
  85. MASTER: GRB 040624 optical observation after 0,48d
  86. GRB 040624, optical observations
  87. GRB 040624 - A long GRB detected with INTEGRAL
  88. GRB 030329: Rebrightening of hyperluminal ejecta.
  89. IPN Summary of SGR1806-20 Activity in 2004
  90. SGR 1806-20: no IR variability of the proposed counterparts
  91. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  92. SGR 1806-20, potential NIR counterpart
  93. GRB 040606: Optical observations
  94. MASTER: HETE Alert 3274 optical observation
  95. Activivty of SGR 1806-20
  96. GRB 040511, very fast decay?
  97. GRB 030324: Detection and Color of Host Galaxy
  98. GRB 040511: NIR observations with REM
  99. GRB040511: Candidate optical/NIR afterglow
  100. GRB 040511: ROTSE-III Rapid Optical Upper Limits

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