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"

41682 results found.

  1. GRB 021201: Optical Observations
  2. GRB 021211, optical observations
  3. GRB 021211: CTIO observations
  4. GRB021211: Measurement of Early Time Afterglow
  5. VLT spectrum of GRB 021211
  6. GRB 021211: early break in light curve
  7. GRB021211, BVRI field photometry
  8. GRB021211: Optical observations in CrAO
  9. GRB 021211, IR observations
  10. GRB 021211, optical observations
  11. GRB 021211: Optical Observations
  12. GRB021211: Kiso Observations
  13. GRB021204: Kiso Observations
  14. GRB 021201, optical observations
  15. GRB 021211: Radio Observations
  16. GRB021211: Optical observations
  17. GRB 021201 (short/hard), NOT observations
  18. SUB-MM SEARCH FOR GRB 021211
  19. Chandra observation of the IPN error box of GRB021201 (short/hard)
  20. GRB 021211, R- and I-band observations
  21. GRB021211 - Upper limits from recent and historical observations
  22. GRB021211, OT at 108 s
  23. GRB021211 (HETE2493), OT at 143 sec
  24. GRB 021204: I-band Observations
  25. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  26. HETE 2493: Optical observations
  27. GRB 021125: Radio Observations
  28. IPN triangulation of GRB021206 (small error box)
  29. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  30. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  31. GRB021201, BVRcIc field photometry
  32. GRB 021201, Radio Observations
  33. GRB 021201: Optical Observations
  34. GRB 021201: BOOTES simultaneous optical observations
  35. Radio Catalog of GRB Afterglows
  36. GRB021004, late time optical observations
  37. GRB021004 Chandra Observation
  38. GRB021125 refined position
  39. IPN triangulation of GRB021125B (two large error boxes)
  40. IPN triangulation of GRB021119 (large error box)
  41. Improved IPN error box for GRB021125
  42. IPN BURST POSITION
  43. GRB021125 : A long GRB localized by INTEGRAL
  44. IPN confirmation of the reactivation of SGR1900+14
  45. GRB021113, SPI ACS observation
  46. GRB 021112: Afterglow or Variable Star?
  47. GRB021113: optical observations at Bisei
  48. GRB 021113: Evidence for a Dark Optical Afterglow
  49. GRB021112, BVRI field photometry
  50. GRB 021112: Variable Source in R-band search
  51. GRB021112: Optical Observations
  52. IPN triangulation of GRB021109 (portion of annulus)
  53. IPN triangulation of GRB021113 (=H2449; annulus)
  54. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  55. GRB 021112: RAPTOR Observations
  56. GRB 021113: Optical Observations
  57. GRB 021113: Optical Observations
  58. GRB021113 (=H2449): A Long GRB Localized by HETE
  59. GRB 021112: Optical Observations
  60. GRB 021112: R-band search
  61. IPN triangulation of GRB021108 (large error box)
  62. GRB021112 (=H2448): A Long GRB Localized by HETE
  63. GRB 021016: Optical Observations
  64. IPN triangulation of GRB021109 (annulus)
  65. GRB021004: Near infrared spectroscopy
  66. GRB021104: Optical Observations
  67. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  68. SGR1900+14 activity, November 2-4, 2002
  69. Spectropolarimetry of GRB021004
  70. GRB021104: Optical observations
  71. GRB021104: optical observations
  72. GRB021104: Candidate present in DSS
  73. GRB021104: possible optical afterglow
  74. Detection of activity from SGR 1900+14 with the RXTE/PCA
  75. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  76. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  77. IPN triangulation of GRB021025 (portion of annulus)
  78. IPN triangulation of GRB021027 (single large error box)
  79. GRB021004, late-time optical observations
  80. IPN triangulation of GRB021027 (two large error boxes)
  81. GRB 021023: Infrared Imaging
  82. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  83. IPN triangulation of SGR1900+14, October 22 2002
  84. GRB 021004: optical observations
  85. GRB021004: Optical Observations
  86. GRB 020813; likely host galaxy.
  87. IPN triangulation of GRB021020 (smaller error box)
  88. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  89. GRB 021008, radio observations
  90. GRB 021016, optical observations
  91. GRB 021004: VRI observations at TNG: possible break
  92. GRB021016, optical observations
  93. SGR1900+14: burst on October 10 2002
  94. GRB 021008, optical observations
  95. GRB021016(=H2397): A Long GRB Localized by HETE
  96. IPN triangulation of GRB021016 (area corrected)
  97. IPN triangulation of GRB021016 (small error box)
  98. GRB021004: Optical Observations
  99. IPN triangulation of GRB021013 (single error box)
  100. GRB 021004: optical spectroscopy on Oct 11

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