Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. 030813 SGR event (Konus-Wind observation)
  2. GRB 030817 = H2808 TAROT optical observations
  3. SGR 1808-20 (=H2802): A Possible new SGR
  4. GRB 021206 Optical Observations
  5. IPN triangulation of GRB030808 (two large error boxes)
  6. IPN triangulation of GRB030806 (large burst; large error box)
  7. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  8. IPN/HETE summary of recent bursts from SGR1806-20
  9. XRF 030723: Detection of a rebrightening in the optical afterglow
  10. GRB030725: Optical observations
  11. XRF030723, BVRcIc field photometry update
  12. IPN triangulation of GRB030801 (large error box)
  13. GRB021206 optical counterpart upper limit
  14. IPN triangulation of GRB030731 (annulus)
  15. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  16. XRF030723: Re-analysis of ROTSE-III early images
  17. IPN triangulation of GRB030725 (=H2779; small error box)
  18. XRF030723 (=H2777): Second Epoch Magellan Observations
  19. GRB 030725: optical observations.
  20. GRB030725, optical transient observations
  21. IPN triangulation of GRB030726 (large error box)
  22. IPN triangulation of GRB030722 (large error box)
  23. IPN triangulation of GRB030721 (large error box)
  24. XRF030723 Radio Observations
  25. XRF 030723: confirmation of fading optical counterpart
  26. XRF030723(=H2777): Chandra Observations
  27. XRF 030723: VLT spectra
  28. Magellan Observations of XRF030723 (=H2777)
  29. GRB030723: Upper limits from historical observations
  30. GRB030725, possible optical transient
  31. XRF030723: Palomar observations and proposed counterpart
  32. GRB030725 (=H2779): A Bright GRB Localized by HETE
  33. XRF030723: optical observations
  34. XRF030723 (= H2777): Chandra Observations Scheduled
  35. XRF030723, BVRcIc field photometry correction
  36. XRF030723, ROTSE-III Early Observations
  37. XRF030723, BVRcIc field photometry
  38. XRF 030723, optical observations
  39. XRF030723, optical observations
  40. XRF 030723, optical observations
  41. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  42. GRB030723, optical observations
  43. Konus-Wind detection of the bursts from SGR1806-20 region
  44. IBAS GRB Alerts 969 970
  45. SGR 1806-20, submm observations
  46. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  47. IPN triangulation of GRB030717 (annulus)
  48. RXTE PCA Observations of SGR1806-20 Region
  49. GRB030329: Subaru Optical Spectroscopy
  50. Triangulation of GRB030715 (single large error box)
  51. Triangulation of GRB030714 (single large error box)
  52. 030716 NOT a GRB
  53. IPN triangulation of GRB030714 (two large error boxes)
  54. IPN triangulation of GRB030715 (two large error boxes)
  55. GRB030329: RTT150 optical observations
  56. GRBlog: Compilation of all GCN Circ. data
  57. IPN detection of renewed activity from SGR1806-20
  58. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  59. IPN triangulation of GRB030710 (annulus)
  60. IPN triangulation of GRB030709 (annulus)
  61. GRB030706 triangulation (single large error box)
  62. IPN triangulation of GRB030706 (annulus)
  63. IPN triangulation of GRB030629 (annulus)
  64. GRB030629 triangulation (Konus-Wind -- Helicon annulus)
  65. 030629 NOT a real GRB
  66. GRB030329, optical observation in May
  67. IPN triangulation of GRB030626 (single large error box)
  68. IPN triangulation of GRB030626 (two large error boxes)
  69. GRB030329: second XMM-Newton observation
  70. GRB030418: R optical observations
  71. HETE detection of burst from SGR1806-20
  72. GRB030329 -- RATAN-600 data in April-May
  73. Final IPN error ellipse for GRB021206 (the polarized GRB)
  74. GRB 021206, Radio afterglow candidate
  75. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  76. IPN triangulation of GRB030607 (annulus)
  77. IPN triangulation of GRB030606 (two alternate error boxes)
  78. GRB030329, SPM optical observations (Correction of GCN2075 R band)
  79. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  80. IPN triangulation of GRB030605B (annulus)
  81. GRB 030528: Optical Observations
  82. IPN triangulation of GRB030605 (annulus)
  83. GRB 030528: tentative NIR counterpart
  84. GRB 030528, radio observations
  85. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  86. GRB030329, further radio observations at GMRT
  87. GRB030528, BVRI field photometry
  88. IPN triangulation of GRB030601 (annulus)
  89. GRB030329, SPM optical observations
  90. GRB030528: Chandra TOO Planned
  91. GRB 030519B: optical observations.
  92. MASTER: optical observation GRB030601
  93. GRB030528(=H2724): Revised SXC Localization
  94. GRB 030329: optical observations
  95. GRB 030329/SN 2003dh: Jitter Episode
  96. GRB 030528, Teramo optical observation
  97. GRB 030528 Bisei optical observation
  98. GRB030528 (H2724): A long GRB localized by HETE
  99. GRB 030329: Correction to GCN 2254
  100. GRB 030329: Optical Observations

Advanced

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