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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"

42786 results found.

  1. GRB 020305: Optical observations
  2. XRF/GRB 011030: Detection of the Probable Host Galaxy
  3. GRB 020305: Candidate optical afterglow
  4. Type Ic SN2002bl (SN/GRB?) Radio Observations
  5. GRB020305, optical observations
  6. GRB020305: Optical Observations
  7. IPN triangulation of GRB020305 (HETE 1939)
  8. GRB020305 (=H1939): Localization of a GRB by HETE
  9. GRB 020305: Optical observations
  10. HST Imaging of the afterglow and host of GRB 011121
  11. GRB 010921: HST Observations
  12. IPN detection and localization of Cygnus X-1 flares
  13. GRB020127: Further VLA Observations of Possible Counterparts
  14. RXTE Observations of SGR 1900+14
  15. IPN detection of further SGR1900+14 activity
  16. SGR1900+14 activity
  17. IPN/HETE Detection of Bursts from SGR1900+14
  18. IPN Upper Limits to a GRB Associated With SN2002ap
  19. GRB020124 BVRI field photometry
  20. GRB020127: Palomar and VLA Observations of Possible Counterparts
  21. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  22. SN2002ap (SN/GRB?) Echelle spectra
  23. SN2002ap (SN/GRB?) optical spectrographic observations
  24. GRB020127, WSRT radio observations
  25. GRB020127 Optical Observations
  26. SN 2002ap (SN/GRB?)
  27. SN 2002ap in M74
  28. SN2002ap (SN/GRB?) UBVRI Field Photometry
  29. GRB020127: Chandra Observations and Prospective Counterparts
  30. pre-SN2002ap (SN/GRB?) imaging of M74
  31. Type Ib/c SN2002ap (SN/GRB?)
  32. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  33. GRB020124, optical observations
  34. GRB020127: Optical observations
  35. GRB 020127, I-band observations starting 3.14-hr after the event
  36. IPN detection of further activity from SGR1806-20
  37. IPN triangulation of GRB020127 (=H1902)
  38. GRB010921 Optical Observations
  39. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  40. GRB020124: Optical observations
  41. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  42. GRB020124: Optical observations
  43. GRB 020124: Optical observations
  44. GRB 020124 Optical Observations
  45. IPN triangulation of GRB020124 (HETE 1896)
  46. IPN observations of SGR1806-20
  47. GRB 020124: Optical afterglow
  48. GRB020124(=H1896): Localization of a Long GRB by HETE
  49. HETE 1896: Optical observations
  50. GRB optical counterpart candidate in GCN 1217 is M dwarf
  51. Possible optical counterpart to a GRB
  52. GRB011212, Optical Observations
  53. GRB011211: BeppoSAX/GRBM data
  54. Optical polarization observations for GRB011211
  55. GRB 011211: Detection of the Probable Host Galaxy
  56. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  57. Color indices of the afterglow of GRB011211
  58. GRB011212: Optical observations at Gunma
  59. GRB 011211, spectrum and optical photometry
  60. GRB 011130: Optical Observations of X-ray and Radio Sources
  61. GRB 011130, Radio/X-ray Comparison
  62. GRB011212: Optical observations
  63. GRB 011211: Evidence for an Optical Break
  64. GRB 011211: TNG Spectroscopic Observations
  65. optical follow-up of GRB(XRF) 011211
  66. GRB 011212: optical observation at Oslo (relayed)
  67. GRB 011211: Optical Spectroscopy
  68. GRB 011211, Optical Observations
  69. GRB011212, BVRI field photometry
  70. GRB011211, BVRI field photometry
  71. GRB011212: Optical observations
  72. GRB 011211: BVRi-band photometry
  73. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  74. Fading of the optical source associated of XRF 011211
  75. XMM-Newton observation of GRB011211
  76. GRB 011211 Optical Observations: Likely Afterglow
  77. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  78. GRB 011130: Optical Observations of Chandra Sources
  79. GRB011130 (XRF011130) Chandra Observations
  80. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  81. GRB 011130: Magellan spectroscopy
  82. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  83. GRB011130, optical observations
  84. GRB 011130, K band observations
  85. GRB011130, optical observations
  86. GRB011130 (=XRF011130): Second Revised Localization by HETE
  87. GRB011130 (XRF011130) optical observations
  88. GRB011130 (XRF011130) SDSS PT i-band observations
  89. XRF011130: Infrared Observations
  90. GRB011130, Radio Observations
  91. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  92. GRB011130 (=XRF011130), Optical Observations
  93. XRF011130: NEAT Optical Observations
  94. GRB011130 (=XRF011130): Revised Localization of an X-ray
  95. GRB001109, Radio Monitoring
  96. GRB 011121
  97. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  98. GRB 011121: J-band observations
  99. GRB 011121: NIR observations, host galaxy?
  100. GRB010921 - Milagro GeV/TeV Observations

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