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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"

41680 results found.

  1. IPN triangulation of GRB021013 (annulus)
  2. XRF 020903: flattening of the optical light curve.
  3. GRB021004, UBVRcIc field photometry update
  4. IPN triangulation of GRB021008 (single error box)
  5. GRB021004: Optical Observations
  6. GRB 021004 submm observations
  7. IPN triangulation of GRB021008B (annulus)
  8. IPN triangulation of GRB021008 (two small error boxes)
  9. GRB021004 Chandra HETG Observations
  10. GRB 021004: Optical/NIR Observations
  11. GRB 021004: Additional V-band Polarimetric Observations
  12. GRB021004: optical observation
  13. GRB 021004: Host Galaxy Star Formation Rate
  14. GRB 021004 submm observations
  15. GRB 021004: WC wind?
  16. GRB021004: NIR and Optical observations
  17. GRB 021004: Optical measurement at OHP
  18. GRB 021004: Optical observations, AUDE network
  19. GRB 021004 - VLA Radio Observations
  20. GRB 021004 - Unusual Radio-to-Submm Spectrum
  21. GRB 021004: optical spectroscopy
  22. XRF 020903 spectrum
  23. GRB 021004: HST/STIS spectroscopic observations
  24. GRB021004: optical observations and predicted break time
  25. GRB021004: BVRc photometry
  26. GRB 021004 redshift
  27. GRB021004: restart of optical decay
  28. GRB 021004: Optical Decay
  29. GRB 021004 continued IR fading
  30. HETE fluences for GRB021004
  31. GRB 021004, spectroscopic observations
  32. GRB021004: not fading anymore?
  33. GRB 021004: Optical Photometry at 2.5 Days
  34. GRB 021004: polarimetric observations
  35. GRB 021004: V-band Polarimetric Observations
  36. GRB021004: Update Bisei photometric data
  37. GRB 021004: Optical Decay
  38. GRB021004, astrometric position
  39. GRB021004, Optical Observations
  40. IRAM Millimeter detection of GRB 021004
  41. GRB 021004: Optical observations at RIKEN
  42. GRB 021004 radio observation
  43. GRB 021004: Optical Observations
  44. GRB021004: continued fading
  45. GRB 021004: Optical Photometry at 1.5 Days
  46. GRB021004, Optical Observations
  47. GRB021004, BVRcIc field photometry
  48. GRB 021004: Optical observations
  49. GRB 021004: optical counterpart
  50. GRB 021004, optical observations
  51. GRB021004: Optical Spectroscopy
  52. GRB 021004: Optical Observations
  53. GRB 021004, SPM optical observations
  54. GRB 021004, optical observations
  55. GRB 021004 radio search
  56. GRB 021004: radio observations
  57. GRB 021004: steepening of the optical decay slope
  58. GRB021004: Upper limits from recent and historical observations
  59. XRF020903, BVRI field photometry
  60. GRB021004: optical observations at Nyrola
  61. GRB021004: Absorption redshift
  62. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  63. GRB021004: optical observations at Bisei
  64. GRB 021004: Kyoto observation
  65. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  66. GRB021004: Optical Afterglow
  67. XRF020903: TNG and Asiago photometry
  68. GRB 020903: Optical observations at RIKEN
  69. XRF 020903: Correction to GCN 1560
  70. XRF 020903: VRI observations
  71. IPN triangulation of GRB020926 (single large error box)
  72. GRB 020903: correction to GCN 1557
  73. XRF 020903: R band observations
  74. XRF 020903: Archival Optical Images
  75. Radio Observations of XRF 020903: The Missing Link
  76. XRF 020903: Supernova
  77. IPN triangulation of GRB020926 (two large error boxes)
  78. GRB020924 (ecliptic latitude-only localization)
  79. IPN triangulation of GRB020923 (two error boxes)
  80. IPN annulus for GRB020923
  81. IPN triangulation of GRB020914B
  82. Improved IPN position for GRB020918 (two large error boxes)
  83. IPN annulus for GRB020914B
  84. IPN triangulation of GRB020911 (2 large error boxes)
  85. IPN triangulation of GRB020914 - clarification and additional information
  86. IPN triangulation of GRB020914
  87. GRB 020305: HST/STIS observations
  88. Confirmation of IPN error box for GRB020910
  89. IPN GCN Circulars now to be issued without restriction
  90. Single IPN error box for GRB020904
  91. XRF 020903: optical observation at Kyoto
  92. GRB020322 : HST/STIS observations
  93. XRF 020903: Optical observations
  94. IPN triangulation of GRB020904
  95. XRF 020903: Optical observations
  96. XRF 020903, optical observations
  97. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  98. INTEGRAL GRBs added to GCN
  99. GRB020813: optical observation
  100. GRB020812: optical observation

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