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"

36141 results found.

  1. 030331 NOT A GRB
  2. INTEGRAL GRB 030331
  3. GRB 030324: Optical and NIR Observations
  4. GRB 030328, optical photometry
  5. GRB030329: R band light curve by MASTER
  6. GRB030329 - Light curve flattening
  7. GRB 030329: SARA Optical Observations
  8. GRB 030324, optical search
  9. GRB030329 - near contemporaneous optical limits from CONCAM
  10. GRB 030329, optical observations
  11. GRB 030329: Light curve observed during the change of its slope.
  12. GRB030329, BVRcIc field photometry
  13. GRB030329, SPM optical observations
  14. GRB 030329: Optical Decay
  15. Redshift of GRB 030329
  16. GRB030329: ROTSE network observes steepening of decay curve
  17. GRB 030329, optical photometry
  18. GRB 030329: Optical decay and synthesis
  19. GRB 030329: Radio Observations
  20. GRB 030329, optical spectroscopy
  21. GRB 030329: still bright
  22. GRB 030329: Optical pre-Imaging
  23. GRB 030329: visual observations
  24. GRB 030329: Upper limit from 5.6 hours before trigger
  25. GRB030328: R optical observation
  26. GRB 030323: Gemini South VRI obsevations.
  27. GRB030329: Optical observations
  28. GRB 030329, R-band observations, supplement
  29. GRB030329:optical observations by MASTER
  30. GRB 030329: optical observations
  31. GRB 030329, R-band observations
  32. GRB 030329: OT B and R photometry, decline rate
  33. GRB030329: Upper limits from recent and historical observations.
  34. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  35. RXTE detection of GRB 030329 afterglow
  36. GRB 030329: Optical Afterglow Observations
  37. GRB 030329: precise position from Kyoto images
  38. GRB 030328 Optical Observations
  39. GRB 030328: Optical observations
  40. GRB 030328: optical observations
  41. GRB 030329: Optical afterglow fading
  42. GRB 030329 follow-up
  43. GRB 030329: Optical afterglow candidate
  44. GRB 030329: OT candidate
  45. GRB 030329: Optical afterglow candidate
  46. GRB 030328: OT photometry
  47. VLT spectra of GRB 030328
  48. GRB 030328, optical spectroscopy
  49. GRB 030328, optical observations
  50. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  51. GRB 030328: Optical observations
  52. Re: GRB 030328: Finding chart
  53. GRB 030328: Finding chart
  54. GRB 030328: Optical afterglow candidate
  55. GRB030131, BVRcIc field photometry
  56. Possible GRB030323 localized by INTEGRAL
  57. IPN triangulation of GRB030325 (final analysis)
  58. IPN triangulation of GRB030326 (single small error box)
  59. GRB 030323: SARA Optical Observations
  60. IPN triangulation of GRB030325 (single small error box)
  61. GRB030324, optical observations
  62. IPN triangulation of GRB030325 (two small error boxes)
  63. GRB 030324: TAROT optical observations
  64. GRB 030324 (HETE #2641): Optical observations
  65. GRB030324, Optical Observations
  66. GRB030323: Upper limits from recent and historical observations.
  67. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  68. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  69. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  70. VLT/FORS2 spectra of GRB 030323
  71. GRB030323, ROTSE-III detection of possible optical counterpart
  72. GRB030323, optical observations
  73. GRB030324, BVRcIc field photometry
  74. GRB030323, possible optical counterpart
  75. GRB030323, BVRcIc field calibration
  76. GRB 030324 optical observations
  77. GRB 030320: Optical Observations
  78. GRB 030324, optical observations
  79. IPN triangulation of GRB030320B (annulus)
  80. IPN triangulation of GRB030320 (small error box)
  81. IPN triangulation of GRB030320
  82. Possible GRB 030320 localized by INTEGRAL
  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. IPN triangulation of GRB030304 (annulus)
  95. GRB 030227: Optical observations
  96. GRB030226, BVRc observations
  97. Chandra detection of the X-ray afterglow of GRB 030226
  98. GRB 030226, further optical/NIR imaging
  99. GRB030227, optical observations
  100. GRB 030226: Ic 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