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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"

24755 results found.

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

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