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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"

14819 results found.

  1. GRB 020531, simultaneous optical observations
  2. GRB020531: Detection of Candidate Host Galaxy
  3. GRB020531: Upper Limit for Detection of Two TAROT Sources
  4. IPN detection of possible bursts from SGR1806-20
  5. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  6. HST detection of the likely host galaxy of GRB 020124
  7. The end of BSAX GRB activities
  8. GRB 020124: Optical observations
  9. GRB020410: BeppoSAX NFI observations refined analysis
  10. Mars Odyssey joins the IPN
  11. GRB020405: predicted break
  12. GRB 020409, No Optical Detection to R = 22
  13. GRB 020331 Kyoto observation on March 31
  14. GRB 020409
  15. GRB 020409, No Optical Detection to R = 20
  16. X-ray afterglow of GRB020321
  17. ASM GRB candidate 020406 refined error box
  18. GRB020331: Optical Observations of Afterglow Candidate
  19. GRB020406(?), optical observations
  20. GRB 020405, U-band observations
  21. GRB011212: Optical Observations
  22. GRB 020322: Optical Observations
  23. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  24. GRB 020322 optical observation
  25. GRB020322, optical observations
  26. GRB020321: BeppoSAX/NFI Observations
  27. GRB020321: a faint BeppoSAX detection
  28. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  29. GRB020317, optical observations
  30. GRB 011121: HST Observations reveal an intermediate-time multicolor
  31. XRF/GRB 011030: Detection of the Probable Host Galaxy
  32. GRB020305 (=H1939): Localization of a GRB by HETE
  33. IPN detection and localization of Cygnus X-1 flares
  34. GRB020127: Further VLA Observations of Possible Counterparts
  35. IPN detection of further SGR1900+14 activity
  36. IPN/HETE Detection of Bursts from SGR1900+14
  37. GRB020127: Palomar and VLA Observations of Possible Counterparts
  38. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  39. Type Ib/c SN2002ap (SN/GRB?)
  40. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  41. IPN detection of further activity from SGR1806-20
  42. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  43. GRB020124(=H1896): Localization of a Long GRB by HETE
  44. GRB 011211: Detection of the Probable Host Galaxy
  45. GRB 011211: Evidence for an Optical Break
  46. GRB 011211: TNG Spectroscopic Observations
  47. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  48. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  49. GRB 011130, K band observations
  50. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  51. GRB011130 (=XRF011130): Revised Localization of an X-ray
  52. GRB 011121: J-band observations
  53. GRB 011121: Detection of Bright IR Counterpart
  54. GRB 011030 I-band Observation
  55. The X-ray Flash 011030 ('GRB 011030')
  56. The Radio Afterglow from the X-ray Rich GRB 011030
  57. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  58. GRB 000131: HST Detection of the Host Galaxy
  59. GRB 011030 K-band Observations
  60. GRB011019: ROTSE-III optical observations
  61. GRB010928(=H1770): Localization of a Long GRB by HETE
  62. BeppoSAX/GRBM detection of GRB 010801
  63. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  64. BeppoSAX/GRBM detection of GRB010728
  65. SGR1900+14: High Fluence Burst Localized by HETE
  66. GRB010629: A Burst Localized by HETE
  67. SGR1900+14: Second Burst Localized by HETE
  68. SGR1900+14: A Burst Localized by HETE
  69. IPN detection of SGR1900+14
  70. SGR1806-20: A Second, Intense Burst Localized by HETE
  71. SGR1806-20: Localization by HETE
  72. GRB000301C: Late-time HST/STIS observation
  73. GRB010518: a faint BeppoSAX detection
  74. GRB000418: HST/STIS Second-epoch Observations
  75. SGR 1900+14: No evidence of extended X-ray emission
  76. SGR 1900+14: Detection of extended X-ray emission
  77. GRB 010222: High-Resolution Keck Spectroscopy
  78. GRB 010214, I-band data
  79. GRB 010222 Kyoto optical observation
  80. GRB010214 follow-up from Hanle
  81. GRB010222: Sub-millimeter detection
  82. GRB010222: Optical Observations
  83. GRB010222: possible optical counterpart
  84. GRB010220, Radio and Optical Observations
  85. GRB010213 Optical Observation
  86. GRB010213, Radio Observations
  87. GRB010214 Optical Observation
  88. IPN Status Report
  89. HETE Status
  90. GRB010126 opt. obs.
  91. GRB010126: CONCAM crude optical limits during GRB
  92. GRB010126 optical observations
  93. Optical Observations of GRB 001018 at Keck
  94. GRB 001212 Optical Observation
  95. Confirmation of IPN position for GRB001204
  96. WSRT 4.8 GHz observations of GRB001109
  97. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  98. GRB001007: Optical observations
  99. GRB000926 - Amateur Optical Observations
  100. CONCAM null result on GRB001005

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