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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. GRB021004: Update Bisei photometric data
  2. GRB 021004: Optical Decay
  3. GRB021004, astrometric position
  4. GRB021004, Optical Observations
  5. IRAM Millimeter detection of GRB 021004
  6. GRB 021004: Optical observations at RIKEN
  7. GRB 021004 radio observation
  8. GRB 021004: Optical Observations
  9. GRB021004: continued fading
  10. GRB 021004: Optical Photometry at 1.5 Days
  11. GRB021004, Optical Observations
  12. GRB021004, BVRcIc field photometry
  13. GRB 021004: Optical observations
  14. GRB 021004: optical counterpart
  15. GRB 021004, optical observations
  16. GRB021004: Optical Spectroscopy
  17. GRB 021004: Optical Observations
  18. GRB 021004, SPM optical observations
  19. GRB 021004, optical observations
  20. GRB 021004 radio search
  21. GRB 021004: radio observations
  22. GRB 021004: steepening of the optical decay slope
  23. GRB021004: Upper limits from recent and historical observations
  24. XRF020903, BVRI field photometry
  25. GRB021004: optical observations at Nyrola
  26. GRB021004: Absorption redshift
  27. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  28. GRB021004: optical observations at Bisei
  29. GRB 021004: Kyoto observation
  30. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  31. GRB021004: Optical Afterglow
  32. XRF020903: TNG and Asiago photometry
  33. GRB 020903: Optical observations at RIKEN
  34. XRF 020903: Correction to GCN 1560
  35. XRF 020903: VRI observations
  36. IPN triangulation of GRB020926 (single large error box)
  37. GRB 020903: correction to GCN 1557
  38. XRF 020903: R band observations
  39. XRF 020903: Archival Optical Images
  40. Radio Observations of XRF 020903: The Missing Link
  41. XRF 020903: Supernova
  42. IPN triangulation of GRB020926 (two large error boxes)
  43. GRB020924 (ecliptic latitude-only localization)
  44. IPN triangulation of GRB020923 (two error boxes)
  45. IPN annulus for GRB020923
  46. IPN triangulation of GRB020914B
  47. Improved IPN position for GRB020918 (two large error boxes)
  48. IPN annulus for GRB020914B
  49. IPN triangulation of GRB020918 (annulus)
  50. IPN triangulation of GRB020911 (2 large error boxes)
  51. IPN triangulation of GRB020914 - clarification and additional information
  52. IPN triangulation of GRB020914
  53. GRB 020305: HST/STIS observations
  54. Confirmation of IPN error box for GRB020910
  55. IPN triangulation of GRB020910
  56. IPN GCN Circulars now to be issued without restriction
  57. Single IPN error box for GRB020904
  58. XRF 020903: optical observation at Kyoto
  59. GRB020322 : HST/STIS observations
  60. XRF 020903: Optical observations
  61. IPN triangulation of GRB020904
  62. XRF 020903: Optical observations
  63. IPN detection of a burst from SGR1900+14
  64. XRF 020903, optical observations
  65. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  66. INTEGRAL GRBs added to GCN
  67. GRB020813: optical observation
  68. GRB020812: optical observation
  69. GRB020819(=H2275): Revised Localization with HETE Soft X-ray
  70. SGR1900+14 burst localized by HETE
  71. GRB020813: High-resolution optical spectroscopy
  72. GRB020819: optical observations at Bisei
  73. GRB020812: negative optical observations
  74. GRB 020812: optical observation at Kyoto University
  75. Second epoch K band imaging of GRB 020819
  76. GRB020813, Baade 6.5m data now available
  77. GRB 020813 : HST observations
  78. Confirming no variability for GRB02081
  79. GRB020819 : Optical observations at KISO
  80. GRB 020812: early time optical observation at Ouda Station
  81. GRB020813: VRI Decay Slopes
  82. GRB020813: Magellan BVRI Photometry
  83. GRB 020819 : OT candidate - confirmation of non variability
  84. GRB 020819: Optical observations
  85. K band observation of GRB 020819
  86. GRB020819: optical observations
  87. GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC
  88. IPN triangulation of GRB020819 (HETE 2275)
  89. HETE 2275: Optical observations
  90. GRB020813: optical and NIR observations
  91. GRB020813: Fading X-ray Afterglow Observed with Chandra
  92. GRB020813, UBVRI field calibration
  93. GRB 020813: addendum to GCN 1498
  94. GRB020813: optical observations at Bisei
  95. GRB020813: V-band decay slope
  96. GRB020812: NIR observations
  97. Polarimetry of GRB020813: evidence for variability
  98. GRB020813 IRAM millimeter observations
  99. GRB020812: optical observations
  100. GRB020813: High-Resolution Optical Observations

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