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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"

42780 results found.

  1. IPN triangulation of GRB020305 (HETE 1939)
  2. GRB020305 (=H1939): Localization of a GRB by HETE
  3. GRB 020305: Optical observations
  4. HST Imaging of the afterglow and host of GRB 011121
  5. GRB 010921: HST Observations
  6. IPN detection and localization of Cygnus X-1 flares
  7. GRB020127: Further VLA Observations of Possible Counterparts
  8. RXTE Observations of SGR 1900+14
  9. IPN detection of further SGR1900+14 activity
  10. SGR1900+14 activity
  11. IPN/HETE Detection of Bursts from SGR1900+14
  12. IPN Upper Limits to a GRB Associated With SN2002ap
  13. GRB020124 BVRI field photometry
  14. GRB020127: Palomar and VLA Observations of Possible Counterparts
  15. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  16. SN2002ap (SN/GRB?) Echelle spectra
  17. SN2002ap (SN/GRB?) optical spectrographic observations
  18. GRB020127, WSRT radio observations
  19. GRB020127 Optical Observations
  20. SN 2002ap (SN/GRB?)
  21. SN 2002ap in M74
  22. SN2002ap (SN/GRB?) UBVRI Field Photometry
  23. GRB020127: Chandra Observations and Prospective Counterparts
  24. pre-SN2002ap (SN/GRB?) imaging of M74
  25. Type Ib/c SN2002ap (SN/GRB?)
  26. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  27. GRB020124, optical observations
  28. GRB020127: Optical observations
  29. GRB 020127, I-band observations starting 3.14-hr after the event
  30. IPN detection of further activity from SGR1806-20
  31. IPN triangulation of GRB020127 (=H1902)
  32. GRB010921 Optical Observations
  33. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  34. GRB020124: Optical observations
  35. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  36. GRB020124: Optical observations
  37. GRB 020124: Optical observations
  38. GRB 020124 Optical Observations
  39. IPN triangulation of GRB020124 (HETE 1896)
  40. IPN observations of SGR1806-20
  41. GRB 020124: Optical afterglow
  42. GRB020124(=H1896): Localization of a Long GRB by HETE
  43. HETE 1896: Optical observations
  44. GRB optical counterpart candidate in GCN 1217 is M dwarf
  45. Possible optical counterpart to a GRB
  46. GRB011212, Optical Observations
  47. GRB011211: BeppoSAX/GRBM data
  48. Optical polarization observations for GRB011211
  49. GRB 011211: Detection of the Probable Host Galaxy
  50. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  51. Color indices of the afterglow of GRB011211
  52. GRB011212: Optical observations at Gunma
  53. GRB 011211, spectrum and optical photometry
  54. GRB 011130: Optical Observations of X-ray and Radio Sources
  55. GRB 011130, Radio/X-ray Comparison
  56. GRB011212: Optical observations
  57. GRB 011211: Evidence for an Optical Break
  58. GRB 011211: TNG Spectroscopic Observations
  59. optical follow-up of GRB(XRF) 011211
  60. GRB 011212: optical observation at Oslo (relayed)
  61. GRB 011211: Optical Spectroscopy
  62. GRB 011211, Optical Observations
  63. GRB011212, BVRI field photometry
  64. GRB011211, BVRI field photometry
  65. GRB011212: Optical observations
  66. GRB 011211: BVRi-band photometry
  67. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  68. Fading of the optical source associated of XRF 011211
  69. XMM-Newton observation of GRB011211
  70. GRB 011211 Optical Observations: Likely Afterglow
  71. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  72. GRB 011130: Optical Observations of Chandra Sources
  73. GRB011130 (XRF011130) Chandra Observations
  74. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  75. GRB 011130: Magellan spectroscopy
  76. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  77. GRB011130, optical observations
  78. GRB 011130, K band observations
  79. GRB011130, optical observations
  80. GRB011130 (=XRF011130): Second Revised Localization by HETE
  81. GRB011130 (XRF011130) optical observations
  82. GRB011130 (XRF011130) SDSS PT i-band observations
  83. XRF011130: Infrared Observations
  84. GRB011130, Radio Observations
  85. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  86. GRB011130 (=XRF011130), Optical Observations
  87. XRF011130: NEAT Optical Observations
  88. GRB011130 (=XRF011130): Revised Localization of an X-ray
  89. GRB001109, Radio Monitoring
  90. GRB 011121
  91. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  92. GRB 011121: J-band observations
  93. GRB 011121: NIR observations, host galaxy?
  94. GRB010921 - Milagro GeV/TeV Observations
  95. GRB 011121: HST Scheduled
  96. GRB011121: fainter still
  97. Correction: GCN1157 (GRB 011121)
  98. GRB011121: UBRI Observations
  99. GRB011121
  100. GRB 011121: Radio Observations

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