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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"

27769 results found.

  1. GRB 011130, K band observations
  2. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  3. GRB011130 (=XRF011130): Revised Localization of an X-ray
  4. GRB 011121: J-band observations
  5. GRB 011121: Detection of Bright IR Counterpart
  6. GRB 011030 I-band Observation
  7. The X-ray Flash 011030 ('GRB 011030')
  8. The Radio Afterglow from the X-ray Rich GRB 011030
  9. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  10. GRB 000131: HST Detection of the Host Galaxy
  11. GRB 011030 K-band Observations
  12. GRB011019: ROTSE-III optical observations
  13. GRB010928(=H1770): Localization of a Long GRB by HETE
  14. BeppoSAX/GRBM detection of GRB 010801
  15. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  16. BeppoSAX/GRBM detection of GRB010728
  17. SGR1900+14: High Fluence Burst Localized by HETE
  18. GRB010629: A Burst Localized by HETE
  19. SGR1900+14: Second Burst Localized by HETE
  20. SGR1900+14: A Burst Localized by HETE
  21. IPN detection of SGR1900+14
  22. SGR1806-20: A Second, Intense Burst Localized by HETE
  23. SGR1806-20: Localization by HETE
  24. GRB000301C: Late-time HST/STIS observation
  25. GRB010518: a faint BeppoSAX detection
  26. GRB000418: HST/STIS Second-epoch Observations
  27. SGR 1900+14: No evidence of extended X-ray emission
  28. SGR 1900+14: Detection of extended X-ray emission
  29. GRB 010222: High-Resolution Keck Spectroscopy
  30. GRB 010214, I-band data
  31. GRB 010222 Kyoto optical observation
  32. GRB010214 follow-up from Hanle
  33. GRB010222: Sub-millimeter detection
  34. GRB010222: Optical Observations
  35. GRB010222: possible optical counterpart
  36. GRB010220, Radio and Optical Observations
  37. GRB010213 Optical Observation
  38. GRB010213, Radio Observations
  39. GRB010214 Optical Observation
  40. IPN Status Report
  41. HETE Status
  42. GRB010126 opt. obs.
  43. GRB010126: CONCAM crude optical limits during GRB
  44. GRB010126 optical observations
  45. Optical Observations of GRB 001018 at Keck
  46. GRB 001212 Optical Observation
  47. Confirmation of IPN position for GRB001204
  48. WSRT 4.8 GHz observations of GRB001109
  49. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  50. GRB001007: Optical observations
  51. GRB000926 - Amateur Optical Observations
  52. CONCAM null result on GRB001005
  53. CONCAM crude optical limits before and after GRB000926
  54. GRB 990510: Possible detection of a host galaxy
  55. GRB 000630: Detection of the Optical Afterglow
  56. GRB000620: BeppoSAX WFC and GRBM detection
  57. GRB000615, R-band photometry
  58. GRB980425, HST/STIS observations of the host galaxy
  59. GRB000604 optical non-detection
  60. GRB000604, optical observations
  61. GRB 000418: Detection of the Host Galaxy
  62. X-ray Afterglow of GRB 000529
  63. Possible GRB-related phenomenon
  64. GRB000424, optical observations
  65. GRB000418, Radio detection
  66. GRB000418, K'-band photometry
  67. GRB 000418, Optical Observation
  68. GRB000424, optical observations
  69. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  70. GRB 000301C: A Precise Redshift Determination
  71. GRB 000301C: HST/STIS CCD Imaging of the field
  72. GRB000301C - Host galaxy not detected in R (?)
  73. GRB000301C 250 GHz detection
  74. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  75. GRB000214: BeppoSAX GRBM and WFC Detection
  76. Optical observations of the Chandra X-ray source for GRB000210
  77. GRB000210: possible afterglow detection with BeppoSAX NFI
  78. GRB000210: BeppoSAX GRBM and WFC Detection
  79. GRB 000131 Optical Observations
  80. GRB000126, optical observations
  81. Second RXTE Observation of GRB 000115
  82. GRB 991216 VLBA Observations
  83. GRB 991216: Detection of the Host and/or Absorber Galaxy
  84. GRB 991216 RXTE ASM Observations
  85. GRB 991216 Optical spectroscopy/imaging
  86. GRB 991208 Infrared Detection
  87. GRB 991216--Summary of RXTE Observations
  88. GRB991216 Optical Observations
  89. GRB991208 - millimeter detection
  90. GRB 991208 - OVRO detection
  91. GRB 991208 optical observations
  92. GRB991106: BeppoSAX/BATSE results
  93. GRB 991106, optical observations
  94. GRB991106: the first BeppoSAX short GRB detection?
  95. GRB991105: SAX-GRBM/-WFC detection
  96. GRB 990915 optical observations
  97. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  98. GRB 990806 Optical observations
  99. BeppoSAX NFI Observation of GRB990705
  100. BeppoSAX NFI Observation of GRB990705

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