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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"

12090 results found.

  1. GRB001109, Host Galaxy Spectroscopic Observations
  2. Probable SGR or Short Duration GRB Detected by HETE
  3. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  4. IPN triangulation of GRB010629
  5. GRB010629: A Burst Localized by HETE
  6. SGR1900+14: Second Burst Localized by HETE
  7. Possible burst from SGR1806-20
  8. IPN detection of SGR1900+14
  9. SGR1806-20: A Second, Intense Burst Localized by HETE
  10. SGR1806-20: Localization by HETE
  11. X-ray precursors to the large flare from SGR 1900+14
  12. GRB010427, Gamma Ray Observations
  13. SGR 1900+14: No evidence of extended X-ray emission
  14. SGR 1900+14 : RXTE observations
  15. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  16. SGR1900+14
  17. SGR 1900+14: Correction to GCN 1049
  18. Millimeter observation of SGR 1900+14
  19. SGR 1900+14: Detection of extended X-ray emission
  20. Chandra Observations of SGR 1900+14
  21. SGR 1900+14, Chandra observations
  22. Chandra Observations of SGR 1900+14
  23. SGR1900+14, I-band observations
  24. GRB010326: Localization by HETE
  25. GRB010214, field photometry
  26. GRB010222, field photometry
  27. GRB010214B,Gamma Ray Observations
  28. BeppoSAX ALERT: GRB010220
  29. GRB010214: BeppoSAX WFC and GRBM preliminary data
  30. GRB 010214, Optical Observations
  31. J-Band Observation of GRB 010214.
  32. Possible InfraRed Transient of GRB 010214.
  33. GRB010214 Optical Observation
  34. GRB 010214, optical observations
  35. HETE Status
  36. GRB010126 opt. obs.
  37. IPN/RXTE TRIANGULATION OF GRB010126
  38. GRB010126 optical observations
  39. IPN/RXTE TRIANGULATION OF GRB010126
  40. IPN TRIANGULATION OF GRB010115
  41. IPN triangulation of GRB001219
  42. GRB 001212 optical observation
  43. IPN triangulation of GRB001120
  44. GRB 001109 X-ray afterglow with BeppoSAX
  45. GRB001109: Optical observations
  46. GRB001109: BeppoSAX/NFI Observations
  47. XMM-Newton observation of GRB001025
  48. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  49. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  50. ASM Localization of GRB 001025
  51. GRB001018, Gamma Ray Observations
  52. IPN TRIANGULATION OF GRB001019
  53. GRB 000926 Chandra Observation
  54. IPN triangulation of GRB 001004
  55. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  56. GRB000926 K'-band Observation
  57. IPN triangulation of GRB000925
  58. IPN triangulation of GRB000910
  59. IPN triangulation of GRB000830
  60. HST/STIS observations of the host galaxy of GRB 980329
  61. SGR 1806-20 burst activity
  62. GRB000801 & GRB000730, Gamma Ray Observations
  63. GRB000730, Gamma Ray Observations
  64. GRB000801, Gamma Ray Observations
  65. possible optical counterpart of GRB 000630
  66. IPN triangulation of GRB000630
  67. GRB 000623, optical observations
  68. GRB000620, optical observations
  69. GRB000620: BeppoSAX WFC and GRBM detection
  70. BeppoSAX ALERT: GRB000620
  71. GRB000620: BeppoSAX Alert
  72. GRB000616 [IPN Position]
  73. GRB000615B [IPN Position]
  74. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  75. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  76. GRB000519: Optical observations
  77. IPN triangulation of GRB000516
  78. GRB 000429, optical observation
  79. GRB 000418, UBVRI field photometry
  80. GRB 000418, Optical Observation
  81. GRB 000418, optical observation
  82. GRB 000418, Optical Observation
  83. GRB 000418, Optical Observation
  84. GRB000418, near-infrared observations
  85. IPN error box for GRB000418
  86. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  87. GRB 000408, optical observations
  88. GRB000313, Radio observations
  89. GRB000301C - B and R photometry
  90. GRB 000307, BVRI Field Photometry
  91. IPN error box for GRB000307
  92. GRB 000301C, UBVRI field photometry
  93. GRB 000301C, Optical Observation
  94. GRB 000301A, Radio Observations
  95. GRB 000301C : Optical Candidate
  96. GRB000226 [IPN Position]
  97. GRB 000115 Optical observations
  98. BATSE GRB trigger criterion changed
  99. GRB 000210: BATSE Observations
  100. GRB000210: BeppoSAX GRBM and WFC Detection

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