Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

27402 results found.

  1. GCN GRB OBSERBATION REPORT
  2. GRB 040825A,optical observations
  3. GRB040825A: optical observations
  4. GRB040825B: optical observations
  5. MASTER: GRB040825b optical observation
  6. GRB 040825: Optical observations
  7. XRF040812: possible afterglow second Chandra observation
  8. GRB 040812: Second epoch CXO Observations
  9. GRB040823,optical observation
  10. XRF040812: GMRT observations
  11. XRF 040812: optical observation at VLT
  12. GRB 040812: Optical counterparts of CXO sources
  13. XRF040812: possible afterglow
  14. CXO observation of GRB 040812
  15. GRB 040812: radio observations
  16. GRB040812, optical/IR observations
  17. GRB 040812: a long GRB detected by INTEGRAL
  18. XRF040701: Optical Observations at ESO
  19. GRB 040730, infrared observations
  20. GRB 040730: a long GRB detected with INTEGRAL
  21. Ongoing activity of SGR 1806-20
  22. GRB040624: optical monitoring at TNG
  23. XRF 040701 - optical observations of the decaying Chandra source
  24. XRF040701: Second-Epoch Chandra Observations
  25. XRF040701: VLA Observations
  26. XRF040701: First-Epoch Chandra Observations
  27. GRB040624, optical observations
  28. GRB040706:observation at University of Miyazaki
  29. Optical Observations of GRB040624
  30. GRB 040624: optical observations at TNG and VLT
  31. MASTER: GRB 040624 optical observation after 0,48d
  32. GRB 040624, optical observations
  33. GRB 040624 - A long GRB detected with INTEGRAL
  34. GRB 030329: Rebrightening of hyperluminal ejecta.
  35. IPN Summary of SGR1806-20 Activity in 2004
  36. SGR 1806-20: no IR variability of the proposed counterparts
  37. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  38. SGR 1806-20, potential NIR counterpart
  39. GRB 040606: Optical observations
  40. MASTER: HETE Alert 3274 optical observation
  41. Activivty of SGR 1806-20
  42. GRB 040511, very fast decay?
  43. GRB 030324: Detection and Color of Host Galaxy
  44. GRB 040511: NIR observations with REM
  45. GRB040511: Candidate optical/NIR afterglow
  46. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  47. GRB 040511: Second Epoch Optical Observations
  48. GRB 040511: Optical observations
  49. GRB 040511: Optical Observations
  50. GRB040511: Optical Observations
  51. GRB040511: Optical Observations
  52. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  53. GRB 040423 (=H3175): A Long GRB Localized by HETE
  54. GRB040422 : I-band follow-up observation at Lulin Observatory
  55. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  56. GRB040422, BVRcIc field calibration
  57. GRB 040422,optical observation
  58. GRB 040422: a long GRB detected with INTEGRAL
  59. GRB 040403, deep optical observations
  60. MASTER: HETE Alert 3163, 3167 technical optical observation
  61. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  62. GRB 040403: Optical observations
  63. GRB 040403: a long GRB detected with INTEGRAL
  64. GRB040323: NIR Observations and Variable Object
  65. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  66. GRB 040323, a dark GRB ?
  67. GRB 040323: a long GRB detected with INTEGRAL
  68. GRB040223: Deep NIR NTT data re-analysis
  69. GRB 040223: XMM-Newton results
  70. GRB040223, improved XMM position
  71. GRB 031203, possible supernova
  72. MASTER: RXTE GRB040308 optical observation
  73. IBAS results on a burst from SGR1806-20
  74. INTEGRAL detection of activity from SGR1806-20
  75. RXTE GRB040229 optical observation: no candidate
  76. GRB 040228 Optical observations
  77. GRB040228 : KISO optical follow-up observation
  78. GRB 040223: Deep NIR NTT observations
  79. GRB 040223 : Optical observation (non-detection)
  80. XMM-Newton Images of GRB 040223
  81. GRB 040223, VLA observations
  82. GRB 040223: REM IJK Observations
  83. GRB 040223 XMM-Newton observation ...
  84. GRB 031203 XMM-Newton observation
  85. GRB 040223: further offline analysis
  86. GRB031111, optical observations
  87. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  88. GRB031203: Chandra Observations
  89. GRB040106: refined X-ray transient position
  90. SN 2003dh/GRB030329 late-time optical spectroscopy
  91. GRB 031220: Optical observations of Chandra X-ray sources
  92. XMM-Newton Images of GRB 040106
  93. GRB031220: observation at Univercity of Miyazaki
  94. XMM-Newton observation of GRB040106
  95. GRB 040106 : peak flux
  96. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  97. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  98. GRB031220: Palomar Observations
  99. GRB 031220 : Kyoto Optical Observation
  100. GRB 031220: Subaru observation

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