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"

43604 results found.

  1. Possible GRB 030110 seen by SPI ACS
  2. IPN triangulation of GRB030109 (annulus)
  3. IPN triangulation of GRB030105 (large error box)
  4. IPN triangulation of GRB030102B (refined localization - portion of annulus)
  5. Possible GRB 20030109 seen by SPI ACS
  6. IPN triangulation of GRB030102B (portion of annulus)
  7. IPN triangulation of GRB030102A (large error box)
  8. Coronas-F -Wind triangulation of GRB030102
  9. Possible GRB20030107 seen by SPI-ACS
  10. Possible GRB 20030105 seen by SPI ACS
  11. IPN triangulation of GRB030102 (annulus)
  12. GRB on 20030102 seen by SPI-ACS
  13. VLT spectroscopy of the probable host of GRB 021211
  14. GRB on 20030101 seen by SPI-ACS
  15. IPN triangulation of GRB030101 (two large error boxes)
  16. GRB021226
  17. GRB 021211: Probable Host and Underlying Supernova
  18. GRB 021226 registration by Helicon/Coronas-F
  19. Probable GRB in INTEGRAL SPI-ACS
  20. IPN triangulation of GRB021223 (two large error boxes)
  21. GRB021211, radio observations
  22. GRB 021112: Evidence for Another Dark Optical Afterglow
  23. GRB 021219: OSN optical observations
  24. GRB021219: Radio Observations
  25. GRB021219, optical observations
  26. IPN triangulation of GRB021219 - CORRECTION
  27. IPN triangulation of GRB021219
  28. GRB021219, optical observation by MASTER
  29. GRB021219: Correction to GCN 1766
  30. GRB021219 refined position with INTEGRAL
  31. VLT spectra of GRB 021211 revisited
  32. GRB021219: a long GRB localized by INTEGRAL
  33. GRB021211: APO optical observations
  34. IPN detection of continued activity from SGR1806-20
  35. IPN triangulation of GRB021215 (large error box)
  36. IPN triangulation of GRB021214 (annulus)
  37. XRF 020903 : HST observations
  38. GRB 021201: Optical Observations
  39. GRB 021211, optical observations
  40. GRB 021211: CTIO observations
  41. GRB021211: Measurement of Early Time Afterglow
  42. VLT spectrum of GRB 021211
  43. IPN triangulation of GRB021211B (two large error boxes)
  44. GRB 021211: early break in light curve
  45. GRB021211, BVRI field photometry
  46. GRB 021211, IR observations
  47. GRB 021211, optical observations
  48. GRB021211: Kiso Observations
  49. GRB 021201, optical observations
  50. GRB 021211: Radio Observations
  51. GRB021211: Optical observations
  52. GRB 021201 (short/hard), NOT observations
  53. SUB-MM SEARCH FOR GRB 021211
  54. Chandra observation of the IPN error box of GRB021201 (short/hard)
  55. GRB 021211 Milagro GeV/TeV Observations
  56. GRB 021211, R- and I-band observations
  57. GRB021211 - Upper limits from recent and historical observations
  58. GRB021211, OT at 108 s
  59. GRB021211 (HETE2493), OT at 143 sec
  60. GRB 021204: I-band Observations
  61. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  62. HETE 2493: Optical observations
  63. HETE 2493: Optical candidate
  64. GRB 021204: Optical Observations at RIKEN
  65. GRB 021125: Radio Observations
  66. IPN triangulation of GRB021206 (small error box)
  67. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  68. IPN detection of renewed activity from SGR1806-20
  69. IPN triangulation of GRB021205 (large error box)
  70. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  71. GRB021201, BVRcIc field photometry
  72. GRB 021201, Radio Observations
  73. GRB 021201: BOOTES simultaneous optical observations
  74. IPN triangulation of GRB021201 (short/hard burst, small error box)
  75. Radio Catalog of GRB Afterglows
  76. GRB021004, late time optical observations
  77. GRB021004 Chandra Observation
  78. IPN detection of continued SGR1900+14 activity
  79. GRB021125 refined position
  80. IPN triangulation of GRB021115 (annulus)
  81. IPN triangulation of GRB021125B (two large error boxes)
  82. IPN triangulation of GRB021119 (large error box)
  83. IPN triangulation of GRB021125B (annulus)
  84. Improved IPN error box for GRB021125
  85. IPN BURST POSITION
  86. IPN triangulation of GRB021125 (INTEGRAL BURST)
  87. GRB021125 : A long GRB localized by INTEGRAL
  88. IPN confirmation of the reactivation of SGR1900+14
  89. IPN detection of possible reactivation of SGR1900+14
  90. GRB021113, SPI ACS observation
  91. IPN triangulation of GRB021119 (annulus)
  92. GRB 021112: Afterglow or Variable Star?
  93. GRB021113: optical observations at Bisei
  94. GRB 021113: Evidence for a Dark Optical Afterglow
  95. GRB 021112, Radio Observations
  96. GRB021112, BVRI field photometry
  97. GRB 021112: Variable Source in R-band search
  98. GRB021112: Optical Observations
  99. GRB021113: Kiso Observations
  100. IPN triangulation of GRB021109 (portion of annulus)

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov