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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"

45442 results found.

  1. XRF030824: Optical observations
  2. IPN triangulation of GRB030903 (large error box)
  3. IBAS detection of bursts from SGR 1806-20
  4. Radio Observations of SGR1806-20
  5. IPN triangulation of GRB030831 (annulus)
  6. IPN triangulation of GRB030830 (large error box)
  7. GRB 030824: Candidate Follow-Up
  8. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  9. IPN triangulation of GRB030827 (large error box)
  10. GRB 030823 observation at Ouda
  11. XRF030824: Second-epoch Palomar observations
  12. XRF030824: optical observations
  13. IPN triangulation of GRB030822 (annulus)
  14. GRB030823: optical observations
  15. GRB030823: Palomar observations
  16. XRF030824: Palomar observations
  17. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  18. GRB030823: optical observation at Tokyo Tech
  19. RAPTOR observations of GRB030823
  20. Lulin follow-up observations of GRB030823
  21. IPN triangulation of GRB030821 (=H2814; refined error box)
  22. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  23. Summary of recent IPN and HETE detections of SGR bursts
  24. IPN triangulation of GRB030814 (annulus)
  25. Clarification of GCN 2354 on SGR1806-20
  26. IPN detection of continued activity from SGR1806-20
  27. 030813 SGR event (Konus-Wind observation)
  28. GRB 030817 = H2808 TAROT optical observations
  29. SGR 1808-20 (=H2802): A Possible new SGR
  30. GRB 021206 Optical Observations
  31. IPN triangulation of GRB030808 (two large error boxes)
  32. IPN triangulation of GRB030806 (large burst; large error box)
  33. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  34. IPN/HETE summary of recent bursts from SGR1806-20
  35. XRF 030723: Detection of a rebrightening in the optical afterglow
  36. GRB030725: Optical observations
  37. XRF030723, BVRcIc field photometry update
  38. IPN triangulation of GRB030801 (large error box)
  39. GRB021206 optical counterpart upper limit
  40. IPN triangulation of GRB030731 (annulus)
  41. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  42. XRF030723: Re-analysis of ROTSE-III early images
  43. IPN triangulation of GRB030725 (=H2779; small error box)
  44. XRF030723 (=H2777): Second Epoch Magellan Observations
  45. GRB 030725: optical observations.
  46. GRB030725, optical transient observations
  47. IPN triangulation of GRB030726 (large error box)
  48. IPN triangulation of GRB030722 (large error box)
  49. IPN triangulation of GRB030721 (large error box)
  50. XRF030723 Radio Observations
  51. XRF 030723: confirmation of fading optical counterpart
  52. XRF030723(=H2777): Chandra Observations
  53. XRF 030723: VLT spectra
  54. Magellan Observations of XRF030723 (=H2777)
  55. GRB030723: Upper limits from historical observations
  56. GRB030725, possible optical transient
  57. XRF030723: Palomar observations and proposed counterpart
  58. GRB030725 (=H2779): A Bright GRB Localized by HETE
  59. XRF030723: optical observations
  60. XRF030723 (= H2777): Chandra Observations Scheduled
  61. XRF030723, BVRcIc field photometry correction
  62. XRF030723, ROTSE-III Early Observations
  63. XRF030723, BVRcIc field photometry
  64. XRF 030723, optical observations
  65. XRF030723, optical observations
  66. XRF 030723, optical observations
  67. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  68. GRB030723, optical observations
  69. Konus-Wind detection of the bursts from SGR1806-20 region
  70. IBAS GRB Alerts 969 970
  71. SGR 1806-20, submm observations
  72. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  73. IPN triangulation of GRB030717 (annulus)
  74. RXTE PCA Observations of SGR1806-20 Region
  75. GRB030329: Subaru Optical Spectroscopy
  76. Triangulation of GRB030715 (single large error box)
  77. Triangulation of GRB030714 (single large error box)
  78. 030716 NOT a GRB
  79. IPN triangulation of GRB030714 (two large error boxes)
  80. IPN triangulation of GRB030715 (two large error boxes)
  81. GRB030329: RTT150 optical observations
  82. GRBlog: Compilation of all GCN Circ. data
  83. IPN detection of renewed activity from SGR1806-20
  84. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  85. IPN triangulation of GRB030710 (annulus)
  86. IPN triangulation of GRB030709 (annulus)
  87. GRB030706 triangulation (single large error box)
  88. IPN triangulation of GRB030706 (annulus)
  89. IPN triangulation of GRB030629 (annulus)
  90. GRB030629 triangulation (Konus-Wind -- Helicon annulus)
  91. 030629 NOT a real GRB
  92. GRB030329, optical observation in May
  93. IPN triangulation of GRB030626 (single large error box)
  94. IPN triangulation of GRB030626 (two large error boxes)
  95. GRB030329: second XMM-Newton observation
  96. GRB030418: R optical observations
  97. HETE detection of burst from SGR1806-20
  98. GRB030329 -- RATAN-600 data in April-May
  99. Final IPN error ellipse for GRB021206 (the polarized GRB)
  100. GRB 021206, Radio afterglow candidate

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