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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"

2623 results found.

  1. IPN detection of renewed activity from SGR1806-20
  2. IPN triangulation of GRB021125B (two large error boxes)
  3. IPN triangulation of GRB021119 (large error box)
  4. GRB021125 : A long GRB localized by INTEGRAL
  5. IPN detection of possible reactivation of SGR1900+14
  6. GRB021104: optical observations
  7. GRB021104: possible optical afterglow
  8. IPN triangulation of GRB021020
  9. GRB 021004: VRI observations at TNG: possible break
  10. IPN triangulation of GRB021013 (two small error boxes)
  11. IPN triangulation of GRB021013 (annulus)
  12. XRF 020903: flattening of the optical light curve.
  13. GRB021004, UBVRcIc field photometry update
  14. IPN triangulation of GRB021007 (annulus)
  15. GRB 021004: polarimetric observations
  16. GRB 021004: Optical Observations
  17. XRF020903: TNG and Asiago photometry
  18. XRF 020903: R band observations
  19. XRF 020903: Archival Optical Images
  20. IPN triangulation of GRB020926 (two large error boxes)
  21. IPN triangulation of GRB020923 (two error boxes)
  22. IPN annulus for GRB020923
  23. IPN triangulation of GRB020914B
  24. Improved IPN position for GRB020918 (two large error boxes)
  25. IPN annulus for GRB020914B
  26. IPN triangulation of GRB020911 (2 large error boxes)
  27. IPN triangulation of GRB020914 - clarification and additional information
  28. IPN triangulation of GRB020910
  29. IPN GCN Circulars now to be issued without restriction
  30. GRB 020813 : HST observations
  31. GRB020813: Magellan BVRI Photometry
  32. GRB020813: High-Resolution Optical Observations
  33. GRB020813: optical observations; possible host galaxy
  34. GRB020812: optical observations
  35. IPN triangulation of GRB020813
  36. GRB020812: possible afterglow candidate
  37. GRB020812: possible afterglow candidate
  38. GRB 020813 Afterglow Observations; Possible break
  39. GRB 020410: Discovery of Probable OT by HST
  40. IPN triangulation of GRB020706
  41. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  42. Fading Optical Source in the Field of GRB020531
  43. GRB 020531, simultaneous optical observations
  44. GRB020531 Optical observations with TAROT
  45. GRB020531 Optical observations with TAROT
  46. IPN triangulation of GRB020604
  47. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  48. IPN triangulation of GRB020603 (possible short/hard GRB)
  49. GRB 020531 optical observations with TAROT
  50. IPN detection of possible bursts from SGR1806-20
  51. GRB020427 BeppoSAX NFI Observation
  52. GRB020405: VLT observations of the OT environment
  53. GRB020405: predicted break
  54. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  55. BeppoSAX ALERT: possible GRB020411
  56. GRB020406(?), optical observations
  57. GRB020410, optical observations
  58. BeppoSAX ALERT: possible GRB020410
  59. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  60. GRB 020321, Radio Observations
  61. GRB020321: BeppoSAX/NFI Observations
  62. GRB 020317: Optical observations
  63. GRB 011121: HST Observations reveal an intermediate-time multicolor
  64. GRB011121, possible supernova association
  65. GRB020127: Further VLA Observations of Possible Counterparts
  66. GRB020127: Palomar and VLA Observations of Possible Counterparts
  67. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  68. SN 2002ap (SN/GRB?)
  69. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  70. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  71. GRB 020124 Optical Observations
  72. GRB optical counterpart candidate in GCN 1217 is M dwarf
  73. Possible optical counterpart to a GRB
  74. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  75. GRB 011130: Magellan spectroscopy
  76. GRB011130, optical observations
  77. GRB 011121: J-band observations
  78. GRB 011121: HST Scheduled
  79. GRB011121: fainter still
  80. GRB011121: continued decay
  81. GRB011121: possible redshift, continued decay
  82. GRB011121: fading behavior
  83. GRB011121: possible optical counterpart
  84. GRB 011030 I-band Observation
  85. GRB 011030, WSRT radio observations
  86. BeppoSAX ALERT: Possible X-ray rich GRB011030
  87. GRB 010921: Possible supernova component
  88. GRB010921: Spectroscopy of the Host Galaxy
  89. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  90. IPN triangulation of GRB010921 (=H1761)
  91. GCN and HETE status
  92. GRB010629: Optical Observations
  93. Possible burst from SGR1806-20
  94. IPN triangulation of GRB010613
  95. HETE Fully-Automated GCN Notices
  96. GRB010214, optical observations
  97. SGR1900+14
  98. Possible precursor to the SGR1900+14 giant burst
  99. Further Optical Observations of GRB 010324
  100. GRB 010222, Optical Observations

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