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"

32505 results found.

  1. GRB 030329: SARA Optical Observations
  2. AAVSO V & R observations of GRB030329
  3. GRB 030329: optical observations
  4. IPN triangulation of GRB030329b (large error box)
  5. GRB 030329: beginning of the new fading phase in optical band
  6. GRB 030329, optical spectroscopy
  7. GRB 030329: fading X-ray afterglow with RXTE
  8. GRB 030329: optical photometry
  9. GRB030329: Optical observations
  10. Photometry of GRB030329 - Constant OT Magnitude
  11. GRB 030329, R-band light curve
  12. GRB 030329: further optical observations
  13. GRB030329 - OT brightens
  14. GRB 030329: OT observations at Kanazawa
  15. GRB030329 15 GHz radio observation
  16. GRB 030329 RBO V Optical Observations
  17. GRB 030329, optical photometry
  18. GRB030329: Near Infrared Observations
  19. GRB 030324: Optical and NIR Observations
  20. GRB 030328, optical photometry
  21. GRB030329: R band light curve by MASTER
  22. GRB030329 - Light curve flattening
  23. GRB 030329: SARA Optical Observations
  24. GRB 030324, optical search
  25. GRB030329 - near contemporaneous optical limits from CONCAM
  26. GRB030329: R and B observations
  27. GRB 030329, optical observations
  28. GRB030329: Optical observations
  29. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  30. GRB030329a: detection by Konus-Wind
  31. GRB 030329: Light curve observed during the change of its slope.
  32. GRB030329, BVRcIc field photometry
  33. GRB030329, SPM optical observations
  34. GRB 030329: Optical Decay
  35. Redshift of GRB 030329
  36. GRB030329: ROTSE network observes steepening of decay curve
  37. GRB 030329, optical photometry
  38. GRB 030329: Optical decay and synthesis
  39. GRB030329 optical observations
  40. GRB030329: optical spectroscopy with the TNG
  41. GRB 030329: Radio Observations
  42. GRB 030329, optical spectroscopy
  43. GRB 030329: still bright
  44. GRB 030329: Optical pre-Imaging
  45. GRB 030329: visual observations
  46. GRB 030329: Upper limit from 5.6 hours before trigger
  47. GRB030328: R optical observation
  48. GRB030328: X-ray Afterglow Observed with Chandra
  49. GRB 030323: Gemini South VRI obsevations.
  50. GRB030329: Optical observations
  51. GRB030329:optical observations by MASTER
  52. GRB 030329: optical observations
  53. GRB 030329, R-band observations
  54. GRB 030329: OT B and R photometry, decline rate
  55. GRB030329: Upper limits from recent and historical observations.
  56. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  57. GRB 030329: Optical Afterglow Observations
  58. GRB 030329: precise position from Kyoto images
  59. GRB 030328 Optical Observations
  60. GRB030328: Decay index
  61. GRB 030328: Optical observations
  62. GRB 030328: optical observations
  63. GRB 030329: Optical afterglow fading
  64. GRB 030328: OT photometry
  65. GRB030328: optical spectroscopy at TNG
  66. GRB030328: optical photometry at the TNG
  67. VLT spectra of GRB 030328
  68. GRB 030328, optical spectroscopy
  69. GRB 030328, optical observations
  70. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  71. GRB 030328: Optical observations
  72. GRB 030328: Finding chart
  73. GRB030323 optical observations
  74. GRB030131, BVRcIc field photometry
  75. IPN triangulation of GRB030325 (final analysis)
  76. GRB030323: Detection on 2003/03/24
  77. GRB 030323: SARA Optical Observations
  78. IPN triangulation of GRB030325 (single small error box)
  79. GRB030324, optical observations
  80. GRB030324, optical observations
  81. GRB 030324: TAROT optical observations
  82. GRB030323: V, R, I photometry
  83. GRB 030324 (HETE #2641): Optical observations
  84. GRB030324, Optical Observations
  85. GRB030323: Upper limits from recent and historical observations.
  86. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  87. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  88. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  89. VLT/FORS2 spectra of GRB 030323
  90. GRB030323, ROTSE-III detection of possible optical counterpart
  91. GRB030323, optical observations
  92. GRB030323, possible optical counterpart
  93. GRB 030324 optical observations
  94. GRB 030320: Optical Observations
  95. IPN triangulation of GRB030320 (small error box)
  96. IPN triangulation of GRB030320
  97. GRB030226, addendum to GCN 1892
  98. IPN upper limit to a GRB associated with SN2003L
  99. GRB 030227: Optical limit at RIKEN
  100. GRB 030226 Optical 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