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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"

45449 results found.

  1. GRB020305, optical observations
  2. GRB020305: Optical Observations
  3. IPN triangulation of GRB020305 (HETE 1939)
  4. GRB020305 (=H1939): Localization of a GRB by HETE
  5. GRB 020305: Optical observations
  6. HST Imaging of the afterglow and host of GRB 011121
  7. GRB 010921: HST Observations
  8. IPN detection and localization of Cygnus X-1 flares
  9. GRB020127: Further VLA Observations of Possible Counterparts
  10. RXTE Observations of SGR 1900+14
  11. IPN detection of further SGR1900+14 activity
  12. SGR1900+14 activity
  13. IPN/HETE Detection of Bursts from SGR1900+14
  14. IPN Upper Limits to a GRB Associated With SN2002ap
  15. GRB020124 BVRI field photometry
  16. GRB020127: Palomar and VLA Observations of Possible Counterparts
  17. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  18. SN2002ap (SN/GRB?) Echelle spectra
  19. SN2002ap (SN/GRB?) optical spectrographic observations
  20. GRB020127, WSRT radio observations
  21. GRB020127 Optical Observations
  22. SN 2002ap (SN/GRB?)
  23. SN 2002ap in M74
  24. SN2002ap (SN/GRB?) UBVRI Field Photometry
  25. GRB020127: Chandra Observations and Prospective Counterparts
  26. pre-SN2002ap (SN/GRB?) imaging of M74
  27. SN 2002ap (hypernova / GRB ??): special list on VSNET
  28. Type Ib/c SN2002ap (SN/GRB?)
  29. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  30. GRB020124, optical observations
  31. GRB020127: Optical observations
  32. GRB 020127, I-band observations starting 3.14-hr after the event
  33. IPN detection of further activity from SGR1806-20
  34. IPN triangulation of GRB020127 (=H1902)
  35. GRB020127 Optical Observations -- Erratum to GCN 1230
  36. GRB010921 Optical Observations
  37. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  38. GRB020124: Optical observations
  39. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  40. GRB020124: Optical observations
  41. GRB 020124: Optical observations
  42. GRB 020124 Optical Observations
  43. IPN triangulation of GRB020124 (HETE 1896)
  44. IPN observations of SGR1806-20
  45. GRB 020124: Optical afterglow
  46. GRB020124(=H1896): Localization of a Long GRB by HETE
  47. HETE 1896: Optical observations
  48. GRB optical counterpart candidate in GCN 1217 is M dwarf
  49. Possible optical counterpart to a GRB
  50. GRB011212, Optical Observations
  51. GRB011211: BeppoSAX/GRBM data
  52. Optical polarization observations for GRB011211
  53. GRB 011211: Detection of the Probable Host Galaxy
  54. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  55. Color indices of the afterglow of GRB011211
  56. GRB011212: Optical observations at Gunma
  57. GRB 011211, spectrum and optical photometry
  58. GRB 011130: Optical Observations of X-ray and Radio Sources
  59. GRB 011130, Radio/X-ray Comparison
  60. GRB011212: Optical observations
  61. GRB 011212: optical observation at Asiago
  62. GRB 011211: Evidence for an Optical Break
  63. GRB 011211: TNG Spectroscopic Observations
  64. optical follow-up of GRB(XRF) 011211
  65. GRB 011212: optical observation at Oslo (relayed)
  66. GRB 011211: Optical Spectroscopy
  67. GRB 011211, Optical Observations
  68. GRB011212, BVRI field photometry
  69. GRB011211, BVRI field photometry
  70. GRB011212: Optical observations
  71. GRB 011211: BVRi-band photometry
  72. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  73. Fading of the optical source associated of XRF 011211
  74. XMM-Newton observation of GRB011211
  75. GRB 011211 Optical Observations: Likely Afterglow
  76. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  77. GRB011211(=XRF011211): BeppoSAX refined positions
  78. BeppoSAX Alert: GRB011211(=XRF011211)
  79. GRB 011130: Optical Observations of Chandra Sources
  80. GRB 011130: Optical Observations of Chandra sources
  81. GRB011130 (XRF011130) Chandra Observations
  82. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  83. GRB 011130: Magellan spectroscopy
  84. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  85. GRB011130, optical observations
  86. GRB 011130, K band observations
  87. GRB011130, optical observations
  88. GRB011130 (=XRF011130): Second Revised Localization by HETE
  89. GRB 011130 I-band Observation
  90. GRB011130 (XRF011130) optical observations
  91. GRB011130 (XRF011130) SDSS PT i-band observations
  92. XRF011130: Infrared Observations
  93. GRB011130, Radio Observations
  94. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  95. GRB011130 (=XRF011130), Optical Observations
  96. XRF011130: NEAT Optical Observations
  97. GRB011130 (=XRF011130): Revised Localization of an X-ray
  98. GRB001109, Radio Monitoring
  99. GRB 011121
  100. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE

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