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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"

28054 results found.

  1. GRB020127 Optical Observations
  2. SN 2002ap in M74
  3. SN2002ap (SN/GRB?) UBVRI Field Photometry
  4. GRB020127: Chandra Observations and Prospective Counterparts
  5. pre-SN2002ap (SN/GRB?) imaging of M74
  6. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  7. GRB020124, optical observations
  8. GRB 020127, I-band observations starting 3.14-hr after the event
  9. GRB010921 Optical Observations
  10. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  11. GRB020124: Optical observations
  12. GRB 020124: Optical observations
  13. GRB 020124: Optical afterglow
  14. GRB020124(=H1896): Localization of a Long GRB by HETE
  15. Possible optical counterpart to a GRB
  16. GRB011212, Optical Observations
  17. Optical polarization observations for GRB011211
  18. GRB 011211: Detection of the Probable Host Galaxy
  19. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  20. GRB 011130: Optical Observations of X-ray and Radio Sources
  21. GRB 011212: optical observation at Asiago
  22. GRB 011211: Evidence for an Optical Break
  23. GRB 011211: TNG Spectroscopic Observations
  24. optical follow-up of GRB(XRF) 011211
  25. GRB 011212: optical observation at Oslo (relayed)
  26. GRB 011211, Optical Observations
  27. GRB011212, BVRI field photometry
  28. GRB011211, BVRI field photometry
  29. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  30. Fading of the optical source associated of XRF 011211
  31. GRB 011211 Optical Observations: Likely Afterglow
  32. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  33. GRB011130 (XRF011130) Chandra Observations
  34. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  35. GRB 011130, K band observations
  36. GRB011130, optical observations
  37. GRB011130 (=XRF011130): Second Revised Localization by HETE
  38. GRB011130 (XRF011130) SDSS PT i-band observations
  39. XRF011130: Infrared Observations
  40. GRB 011121
  41. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  42. GRB 011121: J-band observations
  43. GRB 011121: NIR observations, host galaxy?
  44. GRB011121: UBRI Observations
  45. GRB 011121 J-Band Astrometry
  46. GRB 011121: Detection of Bright IR Counterpart
  47. GRB011121: possible redshift, continued decay
  48. GRB 011030: TNG K-band observation
  49. XRF011030: J and K band observations
  50. XRF011030: Chandra Observations
  51. GRB011030: Z-band observations
  52. GRB 011030 R band observations
  53. GRB 011030 I-band Observation
  54. The X-ray Flash 011030 ('GRB 011030')
  55. Non-triggered burst 011030 ("GRB 011030")
  56. The Radio Afterglow from the X-ray Rich GRB 011030
  57. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  58. GRB 970828: HST Observations of the Host Galaxy
  59. GRB 000131: HST Detection of the Host Galaxy
  60. GRB 970828: HST Observations of the Host Galaxy
  61. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  62. GRB011019: Subaru Optical Observations
  63. GRB 011030 I-band Observations
  64. GRB 011030 K-band Observations
  65. GRB010921, optical observations
  66. GRB011030 - further refinement WFC position
  67. GRB 011030, Radio observations
  68. GRB011030: radio search
  69. GRB 010921: Possible supernova component
  70. GRB010921, optical observation at early time
  71. GRB 010921, I-band observations
  72. GRB011019, optical observations
  73. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  74. GRB 010921: The afterglow of HETE #1761
  75. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  76. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  77. GRB010923 as seen by BeppoSAX GRBM
  78. GRB010928(=H1770): Localization of a Long GRB by HETE
  79. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  80. GRB010921, negative optical observations
  81. GRB010921 field photometry
  82. H1761: A Bright GRB Detected by HETE
  83. GRB000926, Host Galaxy Observations
  84. GRB001109, Host Galaxy Spectroscopic Observations
  85. Probable SGR or Short Duration GRB Detected by HETE
  86. GCN and HETE status
  87. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  88. GRB 010222 - WHT BVRI images
  89. SGR1900+14 burst seen by HETE: BeppoSAX data
  90. GRB 010629 Optical Observations
  91. SGR1900+14: High Fluence Burst Localized by HETE
  92. GRB010629, optical observations
  93. GRB010629: A Burst Localized by HETE
  94. SGR1900+14: Second Burst Localized by HETE
  95. SGR1900+14: A Burst Localized by HETE
  96. SGR1806-20: A Second, Intense Burst Localized by HETE
  97. SGR1806-20: Localization by HETE
  98. HETE Fully-Automated GCN Notices
  99. GRB000301C: Late-time HST/STIS observation
  100. GRB010518: a faint BeppoSAX detection

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