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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').
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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"

23603 results found.

  1. IPN triangulation of GRB021219
  2. GRB021219, optical observation by MASTER
  3. GRB021211: APO optical observations
  4. IPN triangulation of GRB021214 (annulus)
  5. XRF 020903 : HST observations
  6. GRB 021201: Optical Observations
  7. GRB021211: Measurement of Early Time Afterglow
  8. IPN triangulation of GRB021211B (two large error boxes)
  9. GRB021211, BVRI field photometry
  10. GRB021211: Optical observations in CrAO
  11. GRB 021211: Optical Observations
  12. GRB021204: Kiso Observations
  13. GRB021211: Optical observations
  14. GRB 021201 (short/hard), NOT observations
  15. Chandra observation of the IPN error box of GRB021201 (short/hard)
  16. GRB 021211 Milagro GeV/TeV Observations
  17. GRB021211 - Upper limits from recent and historical observations
  18. GRB 021204: I-band Observations
  19. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  20. HETE 2493: Optical observations
  21. HETE 2493: Optical candidate
  22. GRB 021204: Optical Observations at RIKEN
  23. IPN triangulation of GRB021206 (small error box)
  24. IPN triangulation of GRB021206 (exceptionally bright; annulus only)
  25. IPN detection of renewed activity from SGR1806-20
  26. IPN triangulation of GRB021205 (large error box)
  27. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  28. GRB021201, BVRcIc field photometry
  29. GRB 021201: Optical Observations
  30. GRB 021201: BOOTES simultaneous optical observations
  31. IPN triangulation of GRB021201 (short/hard burst, small error box)
  32. GRB021004, late time optical observations
  33. GRB021004 Chandra Observation
  34. IPN triangulation of GRB021115 (annulus)
  35. IPN triangulation of GRB021119 (large error box)
  36. Improved IPN error box for GRB021125
  37. IPN BURST POSITION
  38. IPN triangulation of GRB021125 (INTEGRAL BURST)
  39. GRB021113, SPI ACS observation
  40. IPN triangulation of GRB021119 (annulus)
  41. GRB 021112: Afterglow or Variable Star?
  42. GRB021113: optical observations at Bisei
  43. GRB 021113: Evidence for a Dark Optical Afterglow
  44. GRB021112, BVRI field photometry
  45. GRB021112: Optical Observations
  46. GRB021113: Kiso Observations
  47. IPN triangulation of GRB021109 (portion of annulus)
  48. IPN triangulation of GRB021113 (=H2449; annulus)
  49. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  50. GRB 021113: Optical observations
  51. GRB 021112: RAPTOR Observations
  52. GRB 021113: Optical Observations
  53. GRB 021113: Optical Observations
  54. GRB021113 (=H2449): A Long GRB Localized by HETE
  55. GRB 021112: Optical Observations
  56. IPN triangulation of GRB021108 (large error box)
  57. GRB021112 (=H2448): A Long GRB Localized by HETE
  58. GRB 021016: Optical Observations
  59. IPN triangulation of GRB021109 (annulus)
  60. GRB021104: Optical Observations
  61. IPN triangulation of GRB021104 (annulus)
  62. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  63. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  64. SGR1900+14 activity, November 2-4, 2002
  65. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  66. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  67. IPN triangulation of GRB021025 (portion of annulus)
  68. IPN triangulation of GRB021027 (single large error box)
  69. IPN triangulation of GRB021027 (annulus)
  70. IPN triangulation of GRB021025 (annulus)
  71. IPN triangulation of SGR1900+14, October 22 2002
  72. GRB 021004: optical observations
  73. IPN triangulation of GRB021023 (small error boc)
  74. GRB 020813; likely host galaxy.
  75. IPN triangulation of GRB021020 (smaller error box)
  76. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  77. IPN triangulation of GRB021020
  78. GRB 021004: VRI observations at TNG: possible break
  79. SGR1900+14: burst on October 10 2002
  80. GRB 021008, optical observations
  81. GRB021016(=H2397): A Long GRB Localized by HETE
  82. IPN triangulation of GRB021016 (small error box)
  83. IPN triangulation of GRB021014 (large error box)
  84. IPN triangulation of GRB021013 (single error box)
  85. GRB 021004: optical spectroscopy on Oct 11
  86. IPN triangulation of GRB021013 (two small error boxes)
  87. GRB021004: High-resolution optical spectroscopy
  88. IPN triangulation of GRB021013 (annulus)
  89. XRF 020903: flattening of the optical light curve.
  90. GRB021004, UBVRcIc field photometry update
  91. IPN triangulation of GRB021008 (single error box)
  92. IPN triangulation of GRB021008B (annulus)
  93. IPN triangulation of GRB021008 (two small error boxes)
  94. GRB021004 Chandra HETG Observations
  95. GRB 021004: Optical/NIR Observations
  96. GRB 021004: Additional V-band Polarimetric Observations
  97. GRB021004: optical observation
  98. GRB 021004: WC wind?
  99. GRB021004: NIR and Optical observations
  100. GRB 021004: Optical measurement at OHP

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