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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"

35958 results found.

  1. GRB021004 Chandra Observation
  2. IPN detection of continued SGR1900+14 activity
  3. IPN triangulation of GRB021115 (annulus)
  4. IPN triangulation of GRB021125B (two large error boxes)
  5. IPN triangulation of GRB021119 (large error box)
  6. IPN triangulation of GRB021125B (annulus)
  7. Improved IPN error box for GRB021125
  8. IPN triangulation of GRB021125 (INTEGRAL BURST)
  9. GRB021125 : A long GRB localized by INTEGRAL
  10. IPN confirmation of the reactivation of SGR1900+14
  11. IPN detection of possible reactivation of SGR1900+14
  12. GRB021113, SPI ACS observation
  13. IPN triangulation of GRB021119 (annulus)
  14. GRB 021112: Afterglow or Variable Star?
  15. GRB021113: optical observations at Bisei
  16. GRB 021113: Evidence for a Dark Optical Afterglow
  17. GRB 021112, Radio Observations
  18. GRB021112, BVRI field photometry
  19. GRB 021112: Variable Source in R-band search
  20. GRB021112: Optical Observations
  21. GRB021113: Kiso Observations
  22. IPN triangulation of GRB021109 (portion of annulus)
  23. IPN triangulation of GRB021113 (=H2449; annulus)
  24. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  25. GRB 021113: Optical observations
  26. GRB 021112: RAPTOR Observations
  27. GRB 021113: Optical Observations
  28. GRB 021113: Optical Observations
  29. GRB021113 (=H2449): A Long GRB Localized by HETE
  30. GRB 021112: Optical Observations
  31. GRB 021112: R-band search
  32. IPN triangulation of GRB021108 (large error box)
  33. GRB021112 (=H2448): A Long GRB Localized by HETE
  34. GRB 021016: Optical Observations
  35. IPN triangulation of GRB021109 (annulus)
  36. IPN triangulation of GRB021108 (annulus)
  37. IPN triangulation of GRB021104 (annulus)
  38. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  39. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  40. SGR1900+14 activity, November 2-4, 2002
  41. GRB021104: Candidate present in DSS
  42. IPN triangulation of GRB021102 (annulus)
  43. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  44. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  45. IPN triangulation of GRB021025 (portion of annulus)
  46. IPN triangulation of GRB021027 (single large error box)
  47. GRB021004, late-time optical observations
  48. IPN triangulation of GRB021027 (two large error boxes)
  49. GRB 021023: Infrared Imaging
  50. IPN triangulation of GRB021027 (annulus)
  51. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  52. IPN triangulation of GRB021025 (annulus)
  53. IPN triangulation of SGR1900+14, October 22 2002
  54. GRB 021004: optical observations
  55. IPN triangulation of GRB021023 (small error boc)
  56. GRB 020813; likely host galaxy.
  57. IPN triangulation of GRB021020 (smaller error box)
  58. IPN triangulation of GRB021020
  59. GRB 021008, radio observations
  60. GRB 021016, optical observations
  61. GRB 021004: VRI observations at TNG: possible break
  62. GRB021016, optical observations
  63. SGR1900+14: burst on October 10 2002
  64. GRB 021008, optical observations
  65. GRB021016(=H2397): A Long GRB Localized by HETE
  66. IPN triangulation of GRB021016 (small error box)
  67. IPN triangulation of GRB021014 (large error box)
  68. IPN triangulation of GRB021013 (single error box)
  69. GRB 021004: optical spectroscopy on Oct 11
  70. IPN triangulation of GRB021013 (two small error boxes)
  71. GRB021004: High-resolution optical spectroscopy
  72. IPN triangulation of GRB021013 (annulus)
  73. GRB021004, UBVRcIc field photometry update
  74. IPN triangulation of GRB021008 (single error box)
  75. GRB 021004 submm observations
  76. IPN triangulation of GRB021008B (annulus)
  77. IPN triangulation of GRB021008 (two small error boxes)
  78. GRB 021004: Optical/NIR Observations
  79. GRB 021004: Additional V-band Polarimetric Observations
  80. GRB021004: optical observation
  81. GRB 021004: Host Galaxy Star Formation Rate
  82. GRB 021004 submm observations
  83. GRB 021004: WC wind?
  84. IPN triangulation of GRB021008
  85. GRB 021004: Optical measurement at OHP
  86. GRB 021004: Optical observations, AUDE network
  87. GRB 021004 - VLA Radio Observations
  88. GRB 021004 - Unusual Radio-to-Submm Spectrum
  89. GRB 021004: optical spectroscopy
  90. IPN triangulation of GRB021007 (annulus)
  91. GRB 021004: HST/STIS spectroscopic observations
  92. GRB021004: optical observations and predicted break time
  93. GRB 021004 redshift
  94. GRB 021004: Optical Decay
  95. GRB 021004 continued IR fading
  96. HETE fluences for GRB021004
  97. GRB 021004, spectroscopic observations
  98. GRB021004: not fading anymore?
  99. GRB 021004: Optical Photometry at 2.5 Days
  100. GRB 021004: polarimetric observations

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