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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"

45486 results found.

  1. HETE Prompt GRB Light Curves and Color-Color Diagrams
  2. IPN triangulation of GRB031014 (annulus)
  3. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  4. XRF 030824: additional observations at CFHT
  5. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  6. IPN triangulation of GRB031008 (annulus)
  7. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  8. IPN detection of continued activity from SGR1806-20
  9. IPN triangulation of GRB031007 (two large error boxes)
  10. XRF 030723: Subaru Optical Observations
  11. IPN triangulation of GRB031004B (annulus)
  12. IPN triangulation of GRB031004A (short/hard; annulus)
  13. IPN triangulation of GRB030929 (short/hard; annulus)
  14. A burst from SGR 1806-20 detected with IBAS
  15. XRF 030824: Early follow-up observation at Kiso observatory
  16. XRF 030824: observations at CFHT
  17. IPN triangulation of GRB030926 (short/hard; large error box)
  18. IPN triangulation of GRB030922B (large error box)
  19. XRF 030723: Detection of the likely host galaxy
  20. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  21. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  22. IPN triangulation of GRB030922A (large error box)
  23. IPN triangulation of GRB030921 (large error box)
  24. IPN triangulation of GRB030919 (large error box)
  25. GRB030922 triangulation (annulus)
  26. GRB030913: Subaru Optical Observations
  27. GRB 030913: ROTSE-3c Optical Observations
  28. GRB030913: OT's limit by MASTER
  29. GRB030921 triangulation (annulus)
  30. GRB030913, candidate afterglow observations
  31. GRB 030913, optical candidate
  32. GRB030913: AAVSO optical observations
  33. GRB 030913, BOOTES observations
  34. GRB030913 (=H2849): Confirmation of the Flight Localization
  35. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  36. GRB030913 (=H2849): TAROT Observations
  37. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  38. Magellan Observations of GRB030725 (=H2779)
  39. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  40. IPN triangulation of GRB030908 (annulus)
  41. GRB 030913: Optical limit at RIKEN
  42. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  43. XRF030824: Optical observations
  44. IPN triangulation of GRB030903 (large error box)
  45. IBAS detection of bursts from SGR 1806-20
  46. Radio Observations of SGR1806-20
  47. IPN triangulation of GRB030831 (annulus)
  48. IPN triangulation of GRB030830 (large error box)
  49. GRB 030824: Candidate Follow-Up
  50. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  51. IPN triangulation of GRB030827 (large error box)
  52. GRB 030823 observation at Ouda
  53. XRF030824: Second-epoch Palomar observations
  54. XRF030824: optical observations
  55. IPN triangulation of GRB030822 (annulus)
  56. GRB030823: optical observations
  57. GRB030823: Palomar observations
  58. XRF030824: Palomar observations
  59. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  60. GRB030823: optical observation at Tokyo Tech
  61. RAPTOR observations of GRB030823
  62. Lulin follow-up observations of GRB030823
  63. IPN triangulation of GRB030821 (=H2814; refined error box)
  64. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  65. Summary of recent IPN and HETE detections of SGR bursts
  66. IPN triangulation of GRB030814 (annulus)
  67. Clarification of GCN 2354 on SGR1806-20
  68. IPN detection of continued activity from SGR1806-20
  69. 030813 SGR event (Konus-Wind observation)
  70. GRB 030817 = H2808 TAROT optical observations
  71. SGR 1808-20 (=H2802): A Possible new SGR
  72. GRB 021206 Optical Observations
  73. IPN triangulation of GRB030808 (two large error boxes)
  74. IPN triangulation of GRB030806 (large burst; large error box)
  75. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  76. IPN/HETE summary of recent bursts from SGR1806-20
  77. XRF 030723: Detection of a rebrightening in the optical afterglow
  78. GRB030725: Optical observations
  79. XRF030723, BVRcIc field photometry update
  80. IPN triangulation of GRB030801 (large error box)
  81. GRB021206 optical counterpart upper limit
  82. IPN triangulation of GRB030731 (annulus)
  83. IBAS GRB Alerts 1011-1017 NOT CONFIRMED
  84. XRF030723: Re-analysis of ROTSE-III early images
  85. IPN triangulation of GRB030725 (=H2779; small error box)
  86. XRF030723 (=H2777): Second Epoch Magellan Observations
  87. GRB 030725: optical observations.
  88. GRB030725, optical transient observations
  89. IPN triangulation of GRB030726 (large error box)
  90. IPN triangulation of GRB030722 (large error box)
  91. IPN triangulation of GRB030721 (large error box)
  92. XRF030723 Radio Observations
  93. XRF 030723: confirmation of fading optical counterpart
  94. XRF030723(=H2777): Chandra Observations
  95. XRF 030723: VLT spectra
  96. Magellan Observations of XRF030723 (=H2777)
  97. GRB030723: Upper limits from historical observations
  98. GRB030725, possible optical transient
  99. XRF030723: Palomar observations and proposed counterpart
  100. GRB030725 (=H2779): A Bright GRB Localized by HETE

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