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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"

32510 results found.

  1. GRB020127: Further VLA Observations of Possible Counterparts
  2. IPN detection of further SGR1900+14 activity
  3. SGR1900+14 activity
  4. GRB020124 BVRI field photometry
  5. GRB020127: Palomar and VLA Observations of Possible Counterparts
  6. GRB020127, WSRT radio observations
  7. GRB020127 Optical Observations
  8. SN2002ap (SN/GRB?) UBVRI Field Photometry
  9. GRB020127: Chandra Observations and Prospective Counterparts
  10. pre-SN2002ap (SN/GRB?) imaging of M74
  11. Type Ib/c SN2002ap (SN/GRB?)
  12. GRB020127: Optical observations
  13. GRB 020127, I-band observations starting 3.14-hr after the event
  14. IPN triangulation of GRB020127 (=H1902)
  15. GRB020127 Optical Observations -- Erratum to GCN 1230
  16. GRB010921 Optical Observations
  17. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  18. GRB020124: Optical observations
  19. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  20. GRB020124: Optical observations
  21. GRB 020124: Optical observations
  22. GRB 020124 Optical Observations
  23. IPN triangulation of GRB020124 (HETE 1896)
  24. GRB 020124: Optical afterglow
  25. GRB020124(=H1896): Localization of a Long GRB by HETE
  26. GRB optical counterpart candidate in GCN 1217 is M dwarf
  27. GRB011212, Optical Observations
  28. GRB011211: BeppoSAX/GRBM data
  29. Optical polarization observations for GRB011211
  30. Color indices of the afterglow of GRB011211
  31. GRB011212: Optical observations at Gunma
  32. GRB 011211, spectrum and optical photometry
  33. GRB 011130: Optical Observations of X-ray and Radio Sources
  34. GRB 011130, Radio/X-ray Comparison
  35. GRB011212: Optical observations
  36. GRB 011212: optical observation at Asiago
  37. GRB 011211: Evidence for an Optical Break
  38. GRB 011211: TNG Spectroscopic Observations
  39. optical follow-up of GRB(XRF) 011211
  40. GRB 011212: optical observation at Oslo (relayed)
  41. GRB 011211: Optical Spectroscopy
  42. GRB 011211, Optical Observations
  43. GRB011212, BVRI field photometry
  44. GRB011211, BVRI field photometry
  45. GRB011212: Optical observations
  46. GRB 011211: BVRi-band photometry
  47. Fading of the optical source associated of XRF 011211
  48. XMM-Newton observation of GRB011211
  49. GRB 011211 Optical Observations: Likely Afterglow
  50. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  51. GRB 011130: Optical Observations of Chandra Sources
  52. GRB 011130: Optical Observations of Chandra sources
  53. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  54. GRB 011130: Magellan spectroscopy
  55. GRB011130, optical observations
  56. GRB011130, optical observations
  57. GRB011130 (=XRF011130): Second Revised Localization by HETE
  58. GRB 011130 I-band Observation
  59. GRB011130 (XRF011130) optical observations
  60. GRB011130 (XRF011130) SDSS PT i-band observations
  61. XRF011130: Infrared Observations
  62. GRB011130, Radio Observations
  63. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  64. GRB011130 (=XRF011130), Optical Observations
  65. XRF011130: NEAT Optical Observations
  66. GRB011130 (=XRF011130): Revised Localization of an X-ray
  67. GRB001109, Radio Monitoring
  68. GRB 011121: Errata URL
  69. GRB 011121
  70. GRB 011121: J-band observations
  71. GRB 011121: NIR observations, host galaxy?
  72. GRB010921 - Milagro GeV/TeV Observations
  73. GRB 011121: HST Scheduled
  74. GRB011121: fainter still
  75. Correction: GCN1157 (GRB 011121)
  76. GRB011121: UBRI Observations
  77. GRB011121
  78. GRB 011121: Radio Observations
  79. GRB 011121 J-Band Astrometry
  80. GRB011121: continued decay
  81. GRB 011121: Detection of Bright IR Counterpart
  82. GRB011121: possible redshift, continued decay
  83. GRB011121: fading behavior
  84. GRB011121: possible optical counterpart
  85. IPN triangulation of GRB011121
  86. GRB 011030: TNG K-band observation
  87. XRF011030: J and K band observations
  88. XRF011030: Chandra Observations
  89. GRB 011030: K-band observations
  90. GRB011030: Z-band observations
  91. GRB 011030 I-band Observation
  92. The X-ray Flash 011030 ('GRB 011030')
  93. The Radio Afterglow from the X-ray Rich GRB 011030
  94. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  95. GRB 000131: HST Detection of the Host Galaxy
  96. GRB 011019 optical observation
  97. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  98. GRB011019: Subaru Optical Observations
  99. GRB 011030 I-band Observations
  100. GRB 011030 K-band Observations

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