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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"

2722 results found.

  1. GRB031220: Palomar Observations
  2. GRB 031203: IR NTTobservations do not confirm REM detection
  3. SN 2003jd (SN/GRB?) -- X-ray Observations
  4. IPN triangulation of GRB031016 (two large error boxes)
  5. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  6. IPN triangulation of GRB030921 (large error box)
  7. IPN triangulation of GRB030806 (large burst; large error box)
  8. XRF030723, ROTSE-III Early Observations
  9. XRF030723, optical observations
  10. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  11. IPN triangulation of GRB030715 (two large error boxes)
  12. GRB030329 -- RATAN-600 data in April-May
  13. GRB 030329: Optical limit (contemporaneous imaging)
  14. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  15. IPN triangulation of GRB030425 (single error box)
  16. GRB 030329, the review of the sky area in plate archive (1950-1998)
  17. IPN triangulation of GRB030422 (two large error boxes)
  18. GRB030329: 444 AAVSO Measurements
  19. GRB 030329, nearby galaxies
  20. Further AAVSO V,B,R observations of GRB030329
  21. GRB 030329: Correction to GCN 2056
  22. GRB 030329: optical observations
  23. GRB030323, ROTSE-III detection of possible optical counterpart
  24. GRB030323, possible optical counterpart
  25. IPN triangulation of GRB030320 (small error box)
  26. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  27. GRB 030217: Optical Observations at 4, 5, and 6 Days
  28. GRB030131: Kiso Observations
  29. IPN triangulation of GRB030101 (two large error boxes)
  30. Improved IPN error box for GRB021125
  31. IPN BURST POSITION
  32. IPN triangulation of GRB021125 (INTEGRAL BURST)
  33. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  34. GRB021104: optical observations
  35. GRB021104: possible optical afterglow
  36. IPN triangulation of GRB021027 (single large error box)
  37. IPN triangulation of GRB021020
  38. GRB021016(=H2397): A Long GRB Localized by HETE
  39. IPN triangulation of GRB021016 (small error box)
  40. IPN triangulation of GRB021008 (two small error boxes)
  41. GRB021004: optical observations and predicted break time
  42. GRB021004: BVRc photometry
  43. GRB 021004: optical counterpart
  44. GRB 021004, SPM optical observations
  45. IPN triangulation of GRB020923 (two error boxes)
  46. IPN triangulation of GRB020914 - clarification and additional information
  47. Confirmation of IPN error box for GRB020910
  48. IPN triangulation of GRB020910
  49. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  50. INTEGRAL GRBs added to GCN
  51. IPN error box for GRB020813
  52. GRB020813: Candidate Optical Afterglow
  53. Correction to IPN error box for GRB020706
  54. GRB 020625, optical observations
  55. GRB 020531: optical photometry of Chandra sources
  56. GRB020604, optical observations
  57. GRB020531: Observations with the Chandra X-ray Observatory
  58. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  59. GRB 020124: Optical observations
  60. GRB 020331 Kyoto observation on March 31
  61. GRB020317: optical observations
  62. GRB020321 optical observations
  63. IPN Upper Limits to a GRB Associated With SN2002ap
  64. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  65. GRB020127: Chandra Observations and Prospective Counterparts
  66. GRB 011211, Optical Observations
  67. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  68. GRB011130 (XRF011130) Chandra Observations
  69. GRB011121: fainter still
  70. BEPPOSAX GRB011121
  71. XRF011030: Chandra Observations
  72. Millimeter observation of SGR 1900+14
  73. IPN Triangulation of GRB010412
  74. GRB010214, candidate optical afterglow
  75. GRB010214 Optical Observation
  76. IPN TRIANGULATION OF GRB010109
  77. IPN TRIANGULATION OF GRB010109
  78. XMM-Newton observation of GRB001025
  79. IPN TRIANGULATION OF GRB001020
  80. IPN TRIANGULATION OF GRB001018
  81. GRB000926 - Amateur Optical Observations
  82. GRB 000926 Chandra Observation
  83. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  84. J and K band observations of GRB 000926
  85. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  86. GRB 000926, Optical Observation
  87. GRB 000926: Optical candidate
  88. Optical candidate for GRB000926
  89. GRB000911: Sub-millimeter observations
  90. IPN localization of GRB000812
  91. IPN localization of GRB000811
  92. GRB 000630: Detection of the Optical Afterglow
  93. GRB000630, Revised BVRI Field Photometry
  94. GRB000630, Optical Observations
  95. GRB000630: Optical observations
  96. possible optical counterpart of GRB 000630
  97. IPN triangulation of GRB000630
  98. GRB 000408, optical observations
  99. Radio observations of the error box of GRB000301A
  100. GRB000301A [IPN Position]

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