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"

28044 results found.

  1. GRB030328, UBVRcIc field photometry
  2. GRB 030329 Optical observations
  3. GRB030329: Kiso B and R band observations
  4. GRB030328: R upper limit after 6 hours by MASTER
  5. SDSS 0.5m PT observations of GRB030329 (correction)
  6. SDSS 0.5m PT observations of GRB030329
  7. GRB030329: final R-band light curve by MASTER
  8. GRB030329, optical observation
  9. GRB030329, new UBVRcIc field photometry
  10. GRB 030329, light curve and SN prediction
  11. GRB 030329, BRI photometry
  12. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  13. GRB030329: Optical observations at Teramo
  14. GRB 030329: Radio observations at GMRT
  15. Further AAVSO V,B,R observations of GRB030329
  16. GRB 030329: Additional Mt. Laguna Optical Observations
  17. GRB 030329: Observations with ANDICAM
  18. GRB030329: further optical photometry and evidence for a light curve discontinuity
  19. triangulation of GRB 030331 (single error box)
  20. GRB 030329: optical observations
  21. Photometry of GRB030329 - Constant OT Magnitude
  22. GRB030329 - OT brightens
  23. GRB 030329, optical photometry
  24. GRB 030324: Optical and NIR Observations
  25. GRB030329: R band light curve by MASTER
  26. GRB030329 - Light curve flattening
  27. GRB 030324, optical search
  28. GRB 030329, optical observations
  29. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  30. GRB030329a: detection by Konus-Wind
  31. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  32. GRB030329, BVRcIc field photometry
  33. GRB030329, SPM optical observations
  34. GRB 030329: Optical decay and synthesis
  35. GRB030329 optical observations
  36. GRB 030329: Optical pre-Imaging
  37. GRB 030329: Upper limit from 5.6 hours before trigger
  38. GRB030328: X-ray Afterglow Observed with Chandra
  39. GRB 030329, R-band observations
  40. GRB 030329: OT B and R photometry, decline rate
  41. GRB030329: Upper limits from recent and historical observations.
  42. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  43. GRB 030329: Optical Afterglow Observations
  44. GRB 030328: optical observations
  45. GRB 030329: Optical afterglow fading
  46. GRB 030328: OT photometry
  47. GRB030328: optical spectroscopy at TNG
  48. GRB030328: optical photometry at the TNG
  49. VLT spectra of GRB 030328
  50. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  51. GRB 030328: Optical observations
  52. GRB030324 optical observation
  53. GRB030131, BVRcIc field photometry
  54. Possible GRB030323 localized by INTEGRAL
  55. GRB030323: Detection on 2003/03/24
  56. IPN triangulation of GRB030326 (single small error box)
  57. IPN triangulation of GRB030325 (two small error boxes)
  58. GRB030323: V, R, I photometry
  59. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  60. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  61. VLT/FORS2 spectra of GRB 030323
  62. GRB030323, optical observations
  63. GRB030324, BVRcIc field photometry
  64. GRB030323, BVRcIc field calibration
  65. IPN triangulation of GRB030320 (small error box)
  66. Possible GRB 030320 localized by INTEGRAL
  67. IPN triangulation of GRB030306 (single small error box - REVISED)
  68. IPN triangulation of GRB030306 (single small error box)
  69. IPN triangulation of GRB030306 (two small error boxes)
  70. GRB030226, BVRc observations
  71. Chandra detection of the X-ray afterglow of GRB 030226
  72. GRB030227: Kiso optical upper limit
  73. GRB030227, BVRcIc field photometry
  74. GRB030226, BVRcIc field calibration
  75. GRB 030228, optical observations
  76. GRB 030227: Confirmed Optical Afterglow (S1-A)
  77. GRB 030227: fading of candidate optical afterglow 'S1-A'
  78. GRB030227:Optical observations
  79. GRB 030227, possible optical counterpart of XMM-Newton source
  80. GRB030227 - faint tentative OT candidate
  81. GRB 030226, optical observations
  82. XMM-Newton observation of GRB030227
  83. GRB030227: Kiso optical observations
  84. GRB 030227: Kyoto optical observation
  85. GRB 030226, optical light curve
  86. GRB030227 localized by INTEGRAL
  87. GRB 030226 : Predicted light curve
  88. GRB030226: ESI spectroscopy
  89. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  90. GRB 030226 simultaneous optical observations
  91. GRB 030226, optical observations
  92. GRB030226: Optical decay index
  93. GRB 030226 Optical Spectra and R,I,z' Imaging
  94. GRB: Non-Referencing of GCN Circulars.
  95. IPN triangulation of GRB030217 (small error box)
  96. GRB 030131: marginal optical detection
  97. GRB 030204: Optical Observations
  98. GRB030204 field photometry
  99. GRB020819: Kiso R and I band observations
  100. GRB030131: Candidate Optical Afterglow

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