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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"

24676 results found.

  1. GRB 021113: Optical observations
  2. GRB 021112: RAPTOR Observations
  3. GRB021113 (=H2449): A Long GRB Localized by HETE
  4. GRB021112 (=H2448): A Long GRB Localized by HETE
  5. GRB 021016: Optical Observations
  6. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  7. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  8. SGR1900+14 activity, November 2-4, 2002
  9. GRB021104: optical observations
  10. Detection of activity from SGR 1900+14 with the RXTE/PCA
  11. IPN triangulation of GRB021027 (single large error box)
  12. IPN triangulation of GRB021027 (two large error boxes)
  13. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  14. GRB 021004: optical observations
  15. IPN triangulation of GRB021023 (small error boc)
  16. GRB 020813; likely host galaxy.
  17. IPN triangulation of GRB021020 (smaller error box)
  18. IPN triangulation of GRB021020
  19. GRB 021008, optical observations
  20. IPN triangulation of GRB021016 (small error box)
  21. IPN triangulation of GRB021014 (large error box)
  22. IPN triangulation of GRB021013 (single error box)
  23. GRB 021004: optical spectroscopy on Oct 11
  24. IPN triangulation of GRB021013 (two small error boxes)
  25. GRB021004: High-resolution optical spectroscopy
  26. XRF 020903: flattening of the optical light curve.
  27. GRB021004, UBVRcIc field photometry update
  28. IPN triangulation of GRB021008 (single error box)
  29. GRB 021004 submm observations
  30. IPN triangulation of GRB021008 (two small error boxes)
  31. GRB021004 Chandra HETG Observations
  32. GRB 021004: Optical/NIR Observations
  33. GRB 021004: Additional V-band Polarimetric Observations
  34. GRB021004: optical observation
  35. GRB 021004: Host Galaxy Star Formation Rate
  36. GRB 021004 submm observations
  37. GRB 021004: WC wind?
  38. GRB021004: NIR and Optical observations
  39. GRB 021004: Optical observations, AUDE network
  40. GRB 021004 - VLA Radio Observations
  41. GRB 021004 - Unusual Radio-to-Submm Spectrum
  42. GRB 021004: optical spectroscopy
  43. IPN triangulation of GRB021007 (annulus)
  44. GRB021004: optical observations and predicted break time
  45. GRB021004: BVRc photometry
  46. GRB021004 radio observation
  47. HETE fluences for GRB021004
  48. GRB 021004: Optical Photometry at 2.5 Days
  49. GRB 021004: polarimetric observations
  50. GRB 021004: V-band Polarimetric Observations
  51. GRB021004: Update Bisei photometric data
  52. IRAM Millimeter detection of GRB 021004
  53. GRB 021004 radio observation
  54. GRB 021004: Optical Photometry at 1.5 Days
  55. GRB021004, BVRcIc field photometry
  56. GRB021004: Optical Spectroscopy
  57. GRB 021004 radio search
  58. XRF020903, BVRI field photometry
  59. XRF020903: TNG and Asiago photometry
  60. GRB 020903: Optical observations at RIKEN
  61. XRF 020903: Correction to GCN 1560
  62. XRF 020903: VRI observations
  63. XRF 020903: R band observations
  64. XRF 020903: Archival Optical Images
  65. Radio Observations of XRF 020903: The Missing Link
  66. XRF 020903: Supernova
  67. IPN triangulation of GRB020923 (two error boxes)
  68. IPN triangulation of GRB020914B
  69. IPN triangulation of GRB020911 (2 large error boxes)
  70. GRB 020305: HST/STIS observations
  71. Confirmation of IPN error box for GRB020910
  72. IPN triangulation of GRB020910
  73. IPN GCN Circulars now to be issued without restriction
  74. Single IPN error box for GRB020904
  75. XRF 020903: optical observation at Kyoto
  76. GRB020322 : HST/STIS observations
  77. XRF 020903: Optical observations
  78. IPN triangulation of GRB020904
  79. INTEGRAL GRBs added to GCN
  80. SGR1900+14 burst localized by HETE
  81. GRB020813: High-resolution optical spectroscopy
  82. GRB020812: negative optical observations
  83. GRB 020812: optical observation at Kyoto University
  84. Second epoch K band imaging of GRB 020819
  85. GRB 020813 : HST observations
  86. GRB 020812: early time optical observation at Ouda Station
  87. GRB020813: Magellan BVRI Photometry
  88. GRB 020819: Optical observations
  89. K band observation of GRB 020819
  90. GRB020813: optical and NIR observations
  91. GRB020813: Fading X-ray Afterglow Observed with Chandra
  92. GRB020813, UBVRI field calibration
  93. GRB020812: NIR observations
  94. Polarimetry of GRB020813: evidence for variability
  95. GRB020813 IRAM millimeter observations
  96. GRB020812: optical observations
  97. GRB020813: High-Resolution Optical Observations
  98. GRB 020812: optical observation at Bisei
  99. GRB020813: Early Time Magnitude
  100. Millimeter observation of GRB 020813

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