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"

27321 results found.

  1. GRB 040223: REM IJK Observations
  2. GRB 040223 XMM-Newton observation ...
  3. GRB 031203 XMM-Newton observation
  4. GRB 040223: further offline analysis
  5. GRB031111, optical observations
  6. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  7. GRB031203: Chandra Observations
  8. GRB040106: refined X-ray transient position
  9. SN 2003dh/GRB030329 late-time optical spectroscopy
  10. GRB 031220: Optical observations of Chandra X-ray sources
  11. XMM-Newton Images of GRB 040106
  12. GRB031220: observation at Univercity of Miyazaki
  13. XMM-Newton observation of GRB040106
  14. GRB 040106 : peak flux
  15. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  16. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  17. GRB031220: Palomar Observations
  18. GRB 031220 : Kyoto Optical Observation
  19. GRB 031220: Subaru observation
  20. GRB 031220: Optical observation at Tokyo Tech
  21. GRB 2974 follow-up observations
  22. GRB031203, improved XMM position
  23. GRB 021203: A Normal GRB viewed far off axis?
  24. XMM-Newton Observations of GRB031203: Preliminary Images
  25. GRB 031203: Variable Radio Source
  26. GRB 031203: Magellan spectrum of possible GRB host
  27. GRB 031203: Optical/IR Astrometry
  28. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  29. XMM-Newton Observation of GRB031203
  30. GRB031203: K' Photometry of the likely GRB host
  31. XMM-Newton Observation of GRB031203
  32. GRB 031203: IR NTTobservations do not confirm REM detection
  33. GRB031203 : Optical Observation of Lulin Observatory
  34. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  35. GRB 031203: Apparent Spectral Break
  36. GRB031203: Planned XMM-Newton observation II
  37. GRB 031203: IR REM Observations
  38. GRB031203: Optical Observations
  39. GRB 031203 XMM-Newton observation
  40. GRB031203: Planned XMM-Newton observation
  41. GRB 031203: further analysis of INTEGRAL data
  42. GRB 030329: Planned XMM-Newton Observation
  43. GRB 031111B (= H2925) : Kyoto Optical Observation
  44. IPN triangulation of GRB031114 (large error box)
  45. GRB 031111, optical observations
  46. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  47. GRB030929/SN2003jd association unlikely based on IPN localiztion
  48. IPN triangulation of GRB031027 (small error box)
  49. Lulin optical follow-up observations of GRB031026
  50. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  51. IPN triangulation of GRB031024 (single error box)
  52. IPN triangulation of GRB031024 (annulus)
  53. IPN triangulation of GRB031020 (large error box)
  54. XRF 030824: additional observations at CFHT
  55. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  56. XRF 030723: Subaru Optical Observations
  57. XRF 030824: Early follow-up observation at Kiso observatory
  58. XRF 030824: observations at CFHT
  59. IPN triangulation of GRB030922B (large error box)
  60. XRF 030723: Detection of the likely host galaxy
  61. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  62. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  63. IPN triangulation of GRB030921 (large error box)
  64. IPN triangulation of GRB030919 (large error box)
  65. GRB030913: Subaru Optical Observations
  66. GRB 030913, optical candidate
  67. GRB 030913, BOOTES observations
  68. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  69. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  70. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  71. XRF030824: Optical observations
  72. IPN triangulation of GRB030903 (large error box)
  73. IPN triangulation of GRB030827 (large error box)
  74. GRB030823: optical observations
  75. GRB030823: optical observation at Tokyo Tech
  76. Lulin follow-up observations of GRB030823
  77. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  78. IPN detection of continued activity from SGR1806-20
  79. GRB 030817 = H2808 TAROT optical observations
  80. SGR 1808-20 (=H2802): A Possible new SGR
  81. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  82. XRF 030723: Detection of a rebrightening in the optical afterglow
  83. XRF030723, BVRcIc field photometry update
  84. IPN triangulation of GRB030801 (large error box)
  85. GRB021206 optical counterpart upper limit
  86. IPN triangulation of GRB030726 (large error box)
  87. IPN triangulation of GRB030721 (large error box)
  88. XRF030723 Radio Observations
  89. XRF 030723: confirmation of fading optical counterpart
  90. XRF030723(=H2777): Chandra Observations
  91. GRB030723: Upper limits from historical observations
  92. XRF030723: Palomar observations and proposed counterpart
  93. GRB030725 (=H2779): A Bright GRB Localized by HETE
  94. XRF030723 (= H2777): Chandra Observations Scheduled
  95. XRF030723, BVRcIc field photometry correction
  96. XRF030723, ROTSE-III Early Observations
  97. XRF030723, BVRcIc field photometry
  98. XRF 030723, optical observations
  99. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  100. Konus-Wind detection of the bursts from SGR1806-20 region

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