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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"

32707 results found.

  1. IPN triangulation of GRB021020
  2. GRB 021008, radio observations
  3. GRB 021016, optical observations
  4. GRB 021004: VRI observations at TNG: possible break
  5. GRB021016, optical observations
  6. SGR1900+14: burst on October 10 2002
  7. GRB 021008, optical observations
  8. GRB021016(=H2397): A Long GRB Localized by HETE
  9. IPN triangulation of GRB021016 (small error box)
  10. IPN triangulation of GRB021014 (large error box)
  11. IPN triangulation of GRB021013 (single error box)
  12. GRB 021004: optical spectroscopy on Oct 11
  13. IPN triangulation of GRB021013 (two small error boxes)
  14. GRB021004: High-resolution optical spectroscopy
  15. IPN triangulation of GRB021013 (annulus)
  16. GRB021004, UBVRcIc field photometry update
  17. IPN triangulation of GRB021008 (single error box)
  18. GRB 021004 submm observations
  19. IPN triangulation of GRB021008B (annulus)
  20. IPN triangulation of GRB021008 (two small error boxes)
  21. GRB 021004: Optical/NIR Observations
  22. GRB 021004: Additional V-band Polarimetric Observations
  23. GRB021004: optical observation
  24. GRB 021004: Host Galaxy Star Formation Rate
  25. GRB 021004 submm observations
  26. GRB 021004: WC wind?
  27. IPN triangulation of GRB021008
  28. GRB 021004: Optical measurement at OHP
  29. GRB 021004: Optical observations, AUDE network
  30. GRB 021004 - VLA Radio Observations
  31. GRB 021004 - Unusual Radio-to-Submm Spectrum
  32. GRB 021004: optical spectroscopy
  33. IPN triangulation of GRB021007 (annulus)
  34. GRB 021004: HST/STIS spectroscopic observations
  35. GRB021004: optical observations and predicted break time
  36. GRB 021004 redshift
  37. GRB 021004: Optical Decay
  38. GRB 021004 continued IR fading
  39. HETE fluences for GRB021004
  40. GRB 021004, spectroscopic observations
  41. GRB021004: not fading anymore?
  42. GRB 021004: Optical Photometry at 2.5 Days
  43. GRB 021004: polarimetric observations
  44. GRB 021004: V-band Polarimetric Observations
  45. GRB 021004: Optical Decay
  46. GRB021004, astrometric position
  47. GRB021004, Optical Observations
  48. IRAM Millimeter detection of GRB 021004
  49. GRB 021004: Optical observations at RIKEN
  50. GRB 021004 radio observation
  51. GRB 021004: Optical Observations
  52. GRB021004: continued fading
  53. GRB 021004: Optical Photometry at 1.5 Days
  54. GRB021004, Optical Observations
  55. GRB021004, BVRcIc field photometry
  56. GRB 021004: Optical observations
  57. GRB 021004: optical counterpart
  58. GRB 021004, optical observations
  59. GRB021004: Optical Spectroscopy
  60. GRB 021004: Optical Observations
  61. GRB 021004, SPM optical observations
  62. GRB 021004, optical observations
  63. GRB 021004 radio search
  64. GRB 021004: radio observations
  65. GRB 021004: steepening of the optical decay slope
  66. GRB021004: Upper limits from recent and historical observations
  67. XRF020903, BVRI field photometry
  68. GRB021004: optical observations at Nyrola
  69. GRB021004: Absorption redshift
  70. GRB 021004: Kyoto observation
  71. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  72. GRB021004: Optical Afterglow
  73. GRB 020903: Optical observations at RIKEN
  74. IPN triangulation of GRB020926 (single large error box)
  75. GRB 020903: correction to GCN 1557
  76. XRF 020903: R band observations
  77. Radio Observations of XRF 020903: The Missing Link
  78. IPN triangulation of GRB020926 (two large error boxes)
  79. GRB020924 (ecliptic latitude-only localization)
  80. IPN triangulation of GRB020923 (two error boxes)
  81. IPN annulus for GRB020923
  82. IPN triangulation of GRB020914B
  83. Improved IPN position for GRB020918 (two large error boxes)
  84. IPN annulus for GRB020914B
  85. IPN triangulation of GRB020918 (annulus)
  86. IPN triangulation of GRB020911 (2 large error boxes)
  87. IPN triangulation of GRB020914 - clarification and additional information
  88. IPN triangulation of GRB020914
  89. GRB 020305: HST/STIS observations
  90. Confirmation of IPN error box for GRB020910
  91. IPN triangulation of GRB020910
  92. IPN GCN Circulars now to be issued without restriction
  93. Single IPN error box for GRB020904
  94. XRF 020903: optical observation at Kyoto
  95. GRB020322 : HST/STIS observations
  96. IPN triangulation of GRB020904
  97. IPN detection of a burst from SGR1900+14
  98. INTEGRAL GRBs added to GCN
  99. GRB020813: High-resolution optical spectroscopy
  100. GRB 020812: optical observation at Kyoto University

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