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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"

10761 results found.

  1. AXP 1E2259+586 optical observations
  2. SGR-like Bursts from the AXP 1E 2259+586
  3. GRB 020531, simultaneous optical observations
  4. GRB020531: Second epoch Chandra observations
  5. GRB020531: Observations with the Chandra X-ray Observatory
  6. GRB020531, optical observation
  7. IPN triangulation of the short, hard GRB020531 (=H2042)
  8. GRB020525, optical observations
  9. IPN detection of possible bursts from SGR1806-20
  10. IPN triangulation of GRB020525
  11. XRF 020427: Sudden Ionospheric Disturbance (SID)
  12. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  13. IPN triangulation of a burst from SGR1806-20
  14. GRB 020410, Radio Observations
  15. GRB 020124: Optical observations
  16. IPN triangulation of GRB020418
  17. GRB020410: BeppoSAX NFI observations refined analysis
  18. Mars Odyssey joins the IPN
  19. IPN triangulation of GRB020413
  20. GRB 020409 SARA Observations
  21. GRB 020409, No Optical Detection to R = 20
  22. GRB020410: BeppoSAX NFI observation
  23. GRB 020409, optical observations
  24. GRB020406(?), optical observations
  25. BeppoSAX ALERT: possible GRB020410
  26. GRB020331 optical observations with RIMOTS
  27. GRB020124 optical observations with RIBOTS/RIMOTS
  28. GRB 020321: Candidate X-ray Counterparts
  29. GRB020406(?), optical observations
  30. GRB 020331, NIR observations
  31. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  32. GRB 020321: Optical observations
  33. GRB020317: optical observations
  34. GRB 020317 : KISO Optical Observations
  35. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  36. GRB 020317: Optical observations
  37. GRB020305: Properties of the Candidate Optical Afterglow
  38. GRB011130 (XRF011130) Second Epoch Chandra Observations
  39. GRB020305, optical observations
  40. GRB 020305: Optical observations
  41. GRB 010921: HST Observations
  42. IPN detection and localization of Cygnus X-1 flares
  43. RXTE Observations of SGR 1900+14
  44. SGR1900+14 activity
  45. IPN/HETE Detection of Bursts from SGR1900+14
  46. IPN Upper Limits to a GRB Associated With SN2002ap
  47. SN2002ap (SN/GRB?) optical spectrographic observations
  48. IPN detection of further activity from SGR1806-20
  49. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  50. IPN observations of SGR1806-20
  51. GRB 020124: Optical afterglow
  52. Possible optical counterpart to a GRB
  53. GRB011212, Optical Observations
  54. GRB011212: Optical observations at Gunma
  55. GRB011212: Optical observations
  56. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  57. GRB001109, Radio Monitoring
  58. GRB011121: fainter still
  59. GRB011121: fading behavior
  60. GRB 011030: TNG K-band observation
  61. XRF011030: Chandra Observations
  62. GRB 011030 I-band Observation
  63. The X-ray Flash 011030 ('GRB 011030')
  64. The Radio Afterglow from the X-ray Rich GRB 011030
  65. GRB 011019 optical observation
  66. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  67. GRB011019: Subaru Optical Observations
  68. GRB 011030 K-band Observations
  69. GRB011019: ROTSE-III optical observations
  70. GRB010921: Spectroscopy of the Host Galaxy
  71. GRB010928(=H1770): Localization of a Long GRB by HETE
  72. GRB001109, Host Galaxy Spectroscopic Observations
  73. Probable SGR or Short Duration GRB Detected by HETE
  74. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  75. IPN triangulation of GRB010629
  76. GRB010629: A Burst Localized by HETE
  77. SGR1900+14: Second Burst Localized by HETE
  78. Possible burst from SGR1806-20
  79. IPN detection of SGR1900+14
  80. SGR1806-20: A Second, Intense Burst Localized by HETE
  81. SGR1806-20: Localization by HETE
  82. X-ray precursors to the large flare from SGR 1900+14
  83. GRB010427, Gamma Ray Observations
  84. SGR 1900+14: No evidence of extended X-ray emission
  85. SGR 1900+14 : RXTE observations
  86. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  87. SGR1900+14
  88. SGR 1900+14: Correction to GCN 1049
  89. Millimeter observation of SGR 1900+14
  90. SGR 1900+14: Detection of extended X-ray emission
  91. Chandra Observations of SGR 1900+14
  92. SGR 1900+14, Chandra observations
  93. Chandra Observations of SGR 1900+14
  94. SGR1900+14, I-band observations
  95. GRB010326: Localization by HETE
  96. GRB010214, field photometry
  97. GRB010222, field photometry
  98. GRB010214B,Gamma Ray Observations
  99. BeppoSAX ALERT: GRB010220
  100. GRB010214: BeppoSAX WFC and GRBM preliminary data

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