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"

44623 results found.

  1. GRB 030329: Optical Decay
  2. Redshift of GRB 030329
  3. GRB030329: ROTSE network observes steepening of decay curve
  4. GRB 030329, optical photometry
  5. GRB 030329: Optical decay and synthesis
  6. GRB030329 optical observations
  7. GRB030329: optical spectroscopy with the TNG
  8. GRB 030329: Radio Observations
  9. GRB 030329, optical spectroscopy
  10. GRB 030329: still bright
  11. GRB 030329: Optical pre-Imaging
  12. GRB 030329: visual observations
  13. GRB 030329: Upper limit from 5.6 hours before trigger
  14. GRB030328: R optical observation
  15. GRB030328: X-ray Afterglow Observed with Chandra
  16. GRB 030323: Gemini South VRI obsevations.
  17. GRB030329: Optical observations
  18. GRB 030329, R-band observations, supplement
  19. GRB030329 optical observations
  20. GRB030329:optical observations by MASTER
  21. GRB 030329: optical observations
  22. GRB 030329, R-band observations
  23. GRB 030329: OT B and R photometry, decline rate
  24. GRB030329: Upper limits from recent and historical observations.
  25. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  26. RXTE detection of GRB 030329 afterglow
  27. GRB 030329: Optical Afterglow Observations
  28. GRB 030329: precise position from Kyoto images
  29. GRB 030328 Optical Observations
  30. GRB030328: Decay index
  31. GRB 030328: Optical observations
  32. GRB 030328: optical observations
  33. GRB 030329: Optical afterglow fading
  34. GRB 030329 follow-up
  35. GRB 030329: Optical afterglow candidate
  36. GRB 030329: OT candidate
  37. GRB 030329: Optical afterglow candidate
  38. GRB 030328: OT photometry
  39. GRB030328: optical spectroscopy at TNG
  40. GRB030328: optical photometry at the TNG
  41. VLT spectra of GRB 030328
  42. GRB 030328, optical spectroscopy
  43. GRB 030328, optical observations
  44. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  45. GRB 030328: Optical observations
  46. Re: GRB 030328: Finding chart
  47. GRB 030328: Finding chart
  48. GRB 030328: Optical afterglow candidate
  49. GRB030323 optical observations
  50. GRB030324 optical observation
  51. GRB030131, BVRcIc field photometry
  52. Possible GRB030323 localized by INTEGRAL
  53. IPN triangulation of GRB030325 (final analysis)
  54. GRB030323: Detection on 2003/03/24
  55. IPN triangulation of GRB030326 (single small error box)
  56. GRB 030323: SARA Optical Observations
  57. IPN triangulation of GRB030325 (single small error box)
  58. GRB030324, optical observations
  59. GRB030324, optical observations
  60. IPN triangulation of GRB030325 (two small error boxes)
  61. GRB 030324: TAROT optical observations
  62. GRB030323: V, R, I photometry
  63. GRB 030324 (HETE #2641): Optical observations
  64. GRB030324, Optical Observations
  65. GRB030323: Upper limits from recent and historical observations.
  66. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  67. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  68. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  69. VLT/FORS2 spectra of GRB 030323
  70. GRB030323, ROTSE-III detection of possible optical counterpart
  71. GRB030323, optical observations
  72. GRB030324, BVRcIc field photometry
  73. GRB030323, possible optical counterpart
  74. GRB030323, BVRcIc field calibration
  75. GRB 030324 optical observations
  76. GRB 030320: Optical Observations
  77. GRB 030324, optical observations
  78. IPN triangulation of GRB030320B (annulus)
  79. IPN triangulation of GRB030320 (small error box)
  80. IPN triangulation of GRB030320
  81. Possible GRB 030320 localized by INTEGRAL
  82. GRB030226, addendum to GCN 1892
  83. IPN upper limit to a GRB associated with SN2003L
  84. IPN triangulation of GRB030317 (annulus)
  85. IPN triangulation of GRB030307 (annulus)
  86. GRB 030227: Optical limit at RIKEN
  87. GRB 030226 Optical observations
  88. IPN triangulation of GRB030306 (single small error box - REVISED)
  89. GRB030226: Optical observations at Asiago
  90. IPN triangulation of GRB030306 (single small error box)
  91. IPN triangulation of GRB030306 (two small error boxes)
  92. IPN triangulation of GRB030306 (intense; annulus only so far)
  93. GRB 030226: Optical observations
  94. GRB030226: Analysis of Chandra data
  95. IPN triangulation of GRB030304 (annulus)
  96. GRB 030227: Optical observations
  97. GRB030226, BVRc observations
  98. Chandra detection of the X-ray afterglow of GRB 030226
  99. GRB 030226, further optical/NIR imaging
  100. GRB030227, optical observations

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