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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

26301 results found.

  1. GRB021113: Kiso Observations
  2. IPN triangulation of GRB021113 (=H2449; annulus)
  3. GRB 021112: RAPTOR Observations
  4. GRB021113 (=H2449): A Long GRB Localized by HETE
  5. GRB 021112: R-band search
  6. IPN triangulation of GRB021108 (large error box)
  7. GRB021112 (=H2448): A Long GRB Localized by HETE
  8. IPN triangulation of GRB021109 (annulus)
  9. IPN triangulation of GRB021108 (annulus)
  10. IPN triangulation of GRB021104 (annulus)
  11. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  12. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  13. SGR1900+14 activity, November 2-4, 2002
  14. Spectropolarimetry of GRB021004
  15. GRB021104: optical observations
  16. GRB021104: Candidate present in DSS
  17. IPN triangulation of GRB021102 (annulus)
  18. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  19. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  20. IPN triangulation of GRB021025 (portion of annulus)
  21. IPN triangulation of GRB021027 (single large error box)
  22. IPN triangulation of GRB021027 (two large error boxes)
  23. IPN triangulation of GRB021027 (annulus)
  24. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  25. IPN triangulation of GRB021025 (annulus)
  26. IPN triangulation of SGR1900+14, October 22 2002
  27. GRB 021004: optical observations
  28. IPN triangulation of GRB021023 (small error boc)
  29. GRB021004: Optical Observations
  30. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  31. IPN triangulation of GRB021020
  32. GRB 021004: VRI observations at TNG: possible break
  33. SGR1900+14: burst on October 10 2002
  34. GRB 021008, optical observations
  35. GRB021016(=H2397): A Long GRB Localized by HETE
  36. IPN triangulation of GRB021016 (small error box)
  37. GRB021004: Optical Observations
  38. IPN triangulation of GRB021014 (large error box)
  39. GRB 021004: optical spectroscopy on Oct 11
  40. GRB021004: High-resolution optical spectroscopy
  41. IPN triangulation of GRB021013 (annulus)
  42. GRB021004, UBVRcIc field photometry update
  43. IPN triangulation of GRB021008 (single error box)
  44. GRB021004: Optical Observations
  45. IPN triangulation of GRB021008B (annulus)
  46. IPN triangulation of GRB021008 (two small error boxes)
  47. GRB021004 Chandra HETG Observations
  48. GRB 021004: Optical/NIR Observations
  49. GRB 021004: Additional V-band Polarimetric Observations
  50. GRB021004: optical observation
  51. GRB 021004: Host Galaxy Star Formation Rate
  52. GRB 021004: WC wind?
  53. IPN triangulation of GRB021008
  54. GRB021004: NIR and Optical observations
  55. GRB 021004: Optical observations, AUDE network
  56. GRB 021004 - VLA Radio Observations
  57. IPN triangulation of GRB021007 (annulus)
  58. XRF 020903 spectrum
  59. GRB021004: optical observations and predicted break time
  60. GRB021004: restart of optical decay
  61. GRB 021004 continued IR fading
  62. HETE fluences for GRB021004
  63. GRB 021004, spectroscopic observations
  64. GRB 021004: polarimetric observations
  65. GRB 021004: V-band Polarimetric Observations
  66. GRB021004: Update Bisei photometric data
  67. GRB 021004: Optical Decay
  68. GRB021004, astrometric position
  69. IRAM Millimeter detection of GRB 021004
  70. GRB 021004: Optical observations at RIKEN
  71. GRB 021004: Optical Observations
  72. GRB021004, BVRcIc field photometry
  73. GRB021004: Optical Spectroscopy
  74. GRB 021004: Optical Observations
  75. GRB 021004, SPM optical observations
  76. GRB 021004: radio observations
  77. GRB021004: Upper limits from recent and historical observations
  78. GRB021004: optical observations at Nyrola
  79. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  80. GRB021004: optical observations at Bisei
  81. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  82. GRB021004: Optical Afterglow
  83. XRF020903: TNG and Asiago photometry
  84. GRB 020903: Optical observations at RIKEN
  85. XRF 020903: Correction to GCN 1560
  86. XRF 020903: VRI observations
  87. XRF 020903: R band observations
  88. XRF 020903: Archival Optical Images
  89. Radio Observations of XRF 020903: The Missing Link
  90. XRF 020903: Supernova
  91. IPN triangulation of GRB020926 (two large error boxes)
  92. GRB020924 (ecliptic latitude-only localization)
  93. IPN triangulation of GRB020923 (two error boxes)
  94. IPN annulus for GRB020923
  95. IPN triangulation of GRB020914B
  96. IPN triangulation of GRB020918 (annulus)
  97. IPN triangulation of GRB020911 (2 large error boxes)
  98. IPN triangulation of GRB020914 - clarification and additional information
  99. IPN triangulation of GRB020910
  100. IPN GCN Circulars now to be issued without restriction

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