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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"

42582 results found.

  1. GRB 020317: Optical observations
  2. GRB 011121: Third HST Epoch
  3. GRB020305: Properties of the Candidate Optical Afterglow
  4. GRB 011121: HST Observations reveal an intermediate-time multicolor
  5. GRB011121, possible supernova association
  6. GRB011130 (XRF011130) Second Epoch Chandra Observations
  7. GRB020305: Subaru Optical Observations
  8. XRF/GRB 011030 Images
  9. XRF/GRB 011030: Detection of the Probable Host Galaxy
  10. GRB 020305: Candidate optical afterglow
  11. Type Ic SN2002bl (SN/GRB?) Radio Observations
  12. GRB020305, optical observations
  13. IPN triangulation of GRB020305 (HETE 1939)
  14. GRB020305 (=H1939): Localization of a GRB by HETE
  15. HST Imaging of the afterglow and host of GRB 011121
  16. GRB 010921: HST Observations
  17. IPN detection and localization of Cygnus X-1 flares
  18. GRB020127: Further VLA Observations of Possible Counterparts
  19. RXTE Observations of SGR 1900+14
  20. IPN detection of further SGR1900+14 activity
  21. SGR1900+14 activity
  22. IPN/HETE Detection of Bursts from SGR1900+14
  23. IPN Upper Limits to a GRB Associated With SN2002ap
  24. GRB020124 BVRI field photometry
  25. GRB020127: Palomar and VLA Observations of Possible Counterparts
  26. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  27. SN2002ap (SN/GRB?) Echelle spectra
  28. SN2002ap (SN/GRB?) optical spectrographic observations
  29. GRB020127, WSRT radio observations
  30. GRB020127 Optical Observations
  31. SN 2002ap (SN/GRB?)
  32. SN 2002ap in M74
  33. SN2002ap (SN/GRB?) UBVRI Field Photometry
  34. GRB020127: Chandra Observations and Prospective Counterparts
  35. pre-SN2002ap (SN/GRB?) imaging of M74
  36. SN 2002ap (hypernova / GRB ??): special list on VSNET
  37. Type Ib/c SN2002ap (SN/GRB?)
  38. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  39. GRB 020127, I-band observations starting 3.14-hr after the event
  40. IPN triangulation of GRB020127 (=H1902)
  41. GRB010921 Optical Observations
  42. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  43. GRB020124: Optical observations
  44. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  45. GRB020124: Optical observations
  46. GRB 020124: Optical observations
  47. GRB 020124 Optical Observations
  48. IPN triangulation of GRB020124 (HETE 1896)
  49. IPN observations of SGR1806-20
  50. GRB 020124: Optical afterglow
  51. GRB020124(=H1896): Localization of a Long GRB by HETE
  52. HETE 1896: Optical observations
  53. GRB optical counterpart candidate in GCN 1217 is M dwarf
  54. Possible optical counterpart to a GRB
  55. GRB011212, Optical Observations
  56. GRB011211: BeppoSAX/GRBM data
  57. Optical polarization observations for GRB011211
  58. GRB 011211: Detection of the Probable Host Galaxy
  59. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  60. Color indices of the afterglow of GRB011211
  61. GRB011212: Optical observations at Gunma
  62. GRB 011211, spectrum and optical photometry
  63. GRB 011130, Radio/X-ray Comparison
  64. GRB011212: Optical observations
  65. GRB 011212: optical observation at Asiago
  66. GRB 011211: Evidence for an Optical Break
  67. GRB 011211: TNG Spectroscopic Observations
  68. GRB 011212: optical observation at Oslo (relayed)
  69. GRB 011211: Optical Spectroscopy
  70. GRB 011211, Optical Observations
  71. GRB011212, BVRI field photometry
  72. GRB011211, BVRI field photometry
  73. GRB 011211: BVRi-band photometry
  74. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  75. Fading of the optical source associated of XRF 011211
  76. XMM-Newton observation of GRB011211
  77. GRB 011211 Optical Observations: Likely Afterglow
  78. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  79. GRB 011130: Optical Observations of Chandra Sources
  80. GRB011130 (XRF011130) Chandra Observations
  81. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  82. GRB 011130: Magellan spectroscopy
  83. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  84. GRB011130, optical observations
  85. GRB 011130, K band observations
  86. GRB011130, optical observations
  87. GRB011130 (=XRF011130): Second Revised Localization by HETE
  88. GRB 011130 I-band Observation
  89. GRB011130 (XRF011130) optical observations
  90. GRB011130 (XRF011130) SDSS PT i-band observations
  91. XRF011130: Infrared Observations
  92. GRB011130, Radio Observations
  93. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  94. GRB011130 (=XRF011130), Optical Observations
  95. GRB011130 (=XRF011130): Revised Localization of an X-ray
  96. GRB001109, Radio Monitoring
  97. GRB 011121
  98. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  99. GRB 011121: J-band observations
  100. GRB 011121: NIR observations, host galaxy?

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