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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"

36180 results found.

  1. GRB 021004: WC wind?
  2. IPN triangulation of GRB021008
  3. GRB 021004: Optical measurement at OHP
  4. GRB 021004: Optical observations, AUDE network
  5. GRB 021004 - VLA Radio Observations
  6. GRB 021004 - Unusual Radio-to-Submm Spectrum
  7. GRB 021004: optical spectroscopy
  8. IPN triangulation of GRB021007 (annulus)
  9. GRB 021004: HST/STIS spectroscopic observations
  10. GRB021004: optical observations and predicted break time
  11. GRB 021004 redshift
  12. GRB 021004: Optical Decay
  13. GRB 021004 continued IR fading
  14. HETE fluences for GRB021004
  15. GRB 021004, spectroscopic observations
  16. GRB021004: not fading anymore?
  17. GRB 021004: Optical Photometry at 2.5 Days
  18. GRB 021004: polarimetric observations
  19. GRB 021004: V-band Polarimetric Observations
  20. GRB 021004: Optical Decay
  21. GRB021004, astrometric position
  22. GRB021004, Optical Observations
  23. IRAM Millimeter detection of GRB 021004
  24. GRB 021004: Optical observations at RIKEN
  25. GRB 021004 radio observation
  26. GRB 021004: Optical Observations
  27. GRB021004: continued fading
  28. GRB 021004: Optical Photometry at 1.5 Days
  29. GRB021004, Optical Observations
  30. GRB021004, BVRcIc field photometry
  31. GRB 021004: Optical observations
  32. GRB 021004: optical counterpart
  33. GRB 021004, optical observations
  34. GRB021004: Optical Spectroscopy
  35. GRB 021004: Optical Observations
  36. GRB 021004, SPM optical observations
  37. GRB 021004, optical observations
  38. GRB 021004 radio search
  39. GRB 021004: radio observations
  40. GRB 021004: steepening of the optical decay slope
  41. GRB021004: Upper limits from recent and historical observations
  42. XRF020903, BVRI field photometry
  43. GRB021004: optical observations at Nyrola
  44. GRB021004: Absorption redshift
  45. GRB 021004: Kyoto observation
  46. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  47. GRB021004: Optical Afterglow
  48. GRB 020903: Optical observations at RIKEN
  49. IPN triangulation of GRB020926 (single large error box)
  50. GRB 020903: correction to GCN 1557
  51. XRF 020903: R band observations
  52. Radio Observations of XRF 020903: The Missing Link
  53. IPN triangulation of GRB020926 (two large error boxes)
  54. GRB020924 (ecliptic latitude-only localization)
  55. IPN triangulation of GRB020923 (two error boxes)
  56. IPN annulus for GRB020923
  57. IPN triangulation of GRB020914B
  58. Improved IPN position for GRB020918 (two large error boxes)
  59. IPN annulus for GRB020914B
  60. IPN triangulation of GRB020918 (annulus)
  61. IPN triangulation of GRB020911 (2 large error boxes)
  62. IPN triangulation of GRB020914 - clarification and additional information
  63. IPN triangulation of GRB020914
  64. GRB 020305: HST/STIS observations
  65. Confirmation of IPN error box for GRB020910
  66. IPN triangulation of GRB020910
  67. IPN GCN Circulars now to be issued without restriction
  68. Single IPN error box for GRB020904
  69. XRF 020903: optical observation at Kyoto
  70. GRB020322 : HST/STIS observations
  71. IPN triangulation of GRB020904
  72. IPN detection of a burst from SGR1900+14
  73. INTEGRAL GRBs added to GCN
  74. GRB020813: High-resolution optical spectroscopy
  75. GRB 020812: optical observation at Kyoto University
  76. Second epoch K band imaging of GRB 020819
  77. GRB020813, Baade 6.5m data now available
  78. GRB 020813 : HST observations
  79. Confirming no variability for GRB02081
  80. GRB020819 : Optical observations at KISO
  81. GRB 020812: early time optical observation at Ouda Station
  82. GRB020813: VRI Decay Slopes
  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. GRB020813, UBVRI field calibration
  90. GRB 020813: addendum to GCN 1498
  91. GRB020813: optical observations at Bisei
  92. GRB020813: V-band decay slope
  93. Polarimetry of GRB020813: evidence for variability
  94. GRB020813 IRAM millimeter observations
  95. GRB020812: optical observations
  96. GRB 020812: optical observation at Bisei
  97. GRB020813: optical observations; possible host galaxy
  98. GRB 020813, radio detection
  99. GRB 020812 : optical afterglow candidate
  100. Millimeter observation of GRB 020813

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