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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"

3106 results found.

  1. IPN triangulation of GRB030422 (two large error boxes)
  2. GRB030329: 444 AAVSO Measurements
  3. GRB 030329, nearby galaxies
  4. Further AAVSO V,B,R observations of GRB030329
  5. GRB 030329: Correction to GCN 2056
  6. GRB 030329: optical observations
  7. GRB030323, ROTSE-III detection of possible optical counterpart
  8. GRB030323, possible optical counterpart
  9. IPN triangulation of GRB030320 (small error box)
  10. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  11. GRB 030217: Optical Observations at 4, 5, and 6 Days
  12. GRB030131: Kiso Observations
  13. IPN triangulation of GRB030101 (two large error boxes)
  14. Improved IPN error box for GRB021125
  15. IPN BURST POSITION
  16. IPN triangulation of GRB021125 (INTEGRAL BURST)
  17. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  18. GRB021104: optical observations
  19. GRB021104: possible optical afterglow
  20. IPN triangulation of GRB021027 (single large error box)
  21. IPN triangulation of GRB021020
  22. GRB021016(=H2397): A Long GRB Localized by HETE
  23. IPN triangulation of GRB021016 (small error box)
  24. IPN triangulation of GRB021008 (two small error boxes)
  25. GRB021004: optical observations and predicted break time
  26. GRB021004: BVRc photometry
  27. GRB 021004: optical counterpart
  28. GRB 021004, SPM optical observations
  29. IPN triangulation of GRB020923 (two error boxes)
  30. IPN triangulation of GRB020914 - clarification and additional information
  31. Confirmation of IPN error box for GRB020910
  32. IPN triangulation of GRB020910
  33. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  34. INTEGRAL GRBs added to GCN
  35. IPN error box for GRB020813
  36. GRB020813: Candidate Optical Afterglow
  37. Correction to IPN error box for GRB020706
  38. GRB 020625, optical observations
  39. GRB 020531: optical photometry of Chandra sources
  40. GRB020604, optical observations
  41. GRB020531: Observations with the Chandra X-ray Observatory
  42. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  43. GRB 020124: Optical observations
  44. GRB 020331 Kyoto observation on March 31
  45. GRB020317: optical observations
  46. GRB020321 optical observations
  47. IPN Upper Limits to a GRB Associated With SN2002ap
  48. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  49. GRB020127: Chandra Observations and Prospective Counterparts
  50. GRB 011211, Optical Observations
  51. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  52. GRB011130 (XRF011130) Chandra Observations
  53. GRB011121: fainter still
  54. BEPPOSAX GRB011121
  55. XRF011030: Chandra Observations
  56. Millimeter observation of SGR 1900+14
  57. IPN Triangulation of GRB010412
  58. GRB010214, candidate optical afterglow
  59. GRB010214 Optical Observation
  60. IPN TRIANGULATION OF GRB010109
  61. IPN TRIANGULATION OF GRB010109
  62. XMM-Newton observation of GRB001025
  63. IPN TRIANGULATION OF GRB001020
  64. IPN TRIANGULATION OF GRB001018
  65. GRB000926 - Amateur Optical Observations
  66. GRB 000926 Chandra Observation
  67. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  68. J and K band observations of GRB 000926
  69. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  70. GRB 000926, Optical Observation
  71. GRB 000926: Optical candidate
  72. Optical candidate for GRB000926
  73. GRB000911: Sub-millimeter observations
  74. IPN localization of GRB000812
  75. IPN localization of GRB000811
  76. GRB 000630: Detection of the Optical Afterglow
  77. GRB000630, Revised BVRI Field Photometry
  78. GRB000630, Optical Observations
  79. GRB000630: Optical observations
  80. possible optical counterpart of GRB 000630
  81. IPN triangulation of GRB000630
  82. GRB 000408, optical observations
  83. Radio observations of the error box of GRB000301A
  84. GRB000301A [IPN Position]
  85. GRB000226 [IPN Position]
  86. IPN localization of GRB991226
  87. GRB991216 Optical and infrared observations of Beethoven Burst
  88. GRB991216 ('Beethoven Burst') B, R, and K Observations
  89. IPN localization of GRB991208
  90. IPN localization of GRB991105
  91. IPN localization of GRB991014 - CORRECTION
  92. IPN localization of GRB991014
  93. IPN error box for GRB990915 (=BATSE 7766)
  94. GRB 990704, optical observations
  95. GRB 990506, optical observations from +1 to +3 hours
  96. GRB 990123: BVRI standards in the field
  97. GRB990123 Optical Observations
  98. GRB990123, early optical counterpart detection
  99. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  100. GRB981226, BeppoSAX Christmas GRB

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