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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').
Advanced Search

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"

32509 results found.

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

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