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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"

43601 results found.

  1. GRB 031111: Optical observations
  2. GRB 031111, optical observations
  3. SN 2003jd (SN/GRB?) -- X-ray Observations
  4. HETE Prompt GRB Spectral Analyses
  5. IPN triangulation of GRB031111 (=H2924): small error box
  6. XRF031109 (=H2919): A very long XRF localized by HETE
  7. IPN triangulation of GRB031108 (large error box)
  8. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  9. GRB030929/SN2003jd association unlikely based on IPN localiztion
  10. IPN triangulation of GRB031027 (small error box)
  11. IPN triangulation of GRB031026B (large error box)
  12. SN 2003jd (SN/GRB?), Radio Observations
  13. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  14. GRB 031026: Further Ic Observations
  15. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  16. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  17. IPN triangulation of GRB031024 (single error box)
  18. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  19. GRB 031026: Ic Observations
  20. IPN triangulation of GRB031024 (annulus)
  21. IPN triangulation of GRB031020 (large error box)
  22. GRB030329: radio observations at RT-22 (CrAO)
  23. IPN triangulation of GRB031016 (two large error boxes)
  24. IBAS alert 1180 refers to a burst from SGR 1806-20
  25. HETE Prompt GRB Light Curves and Color-Color Diagrams
  26. IPN triangulation of GRB031014 (annulus)
  27. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  28. XRF 030824: additional observations at CFHT
  29. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  30. IPN triangulation of GRB031008 (annulus)
  31. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  32. IPN detection of continued activity from SGR1806-20
  33. IPN triangulation of GRB031007 (two large error boxes)
  34. XRF 030723: Subaru Optical Observations
  35. IPN triangulation of GRB031004B (annulus)
  36. IPN triangulation of GRB031004A (short/hard; annulus)
  37. IPN triangulation of GRB030929 (short/hard; annulus)
  38. A burst from SGR 1806-20 detected with IBAS
  39. XRF 030824: Early follow-up observation at Kiso observatory
  40. XRF 030824: observations at CFHT
  41. IPN triangulation of GRB030926 (short/hard; large error box)
  42. IPN triangulation of GRB030922B (large error box)
  43. XRF 030723: Detection of the likely host galaxy
  44. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  45. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  46. IPN triangulation of GRB030922A (large error box)
  47. IPN triangulation of GRB030921 (large error box)
  48. IPN triangulation of GRB030919 (large error box)
  49. GRB030922 triangulation (annulus)
  50. GRB030913: Subaru Optical Observations
  51. GRB 030913: ROTSE-3c Optical Observations
  52. GRB030913: OT's limit by MASTER
  53. GRB030921 triangulation (annulus)
  54. GRB030913, candidate afterglow observations
  55. GRB 030913, optical candidate
  56. GRB030913: AAVSO optical observations
  57. GRB030913 (=H2849): Confirmation of the Flight Localization
  58. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  59. GRB030913 (=H2849): TAROT Observations
  60. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  61. Magellan Observations of GRB030725 (=H2779)
  62. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  63. IPN triangulation of GRB030908 (annulus)
  64. GRB 030913: Optical limit at RIKEN
  65. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  66. XRF030824: Optical observations
  67. IPN triangulation of GRB030903 (large error box)
  68. IBAS detection of bursts from SGR 1806-20
  69. Radio Observations of SGR1806-20
  70. IPN triangulation of GRB030831 (annulus)
  71. IPN triangulation of GRB030830 (large error box)
  72. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  73. IPN triangulation of GRB030827 (large error box)
  74. GRB 030823 observation at Ouda
  75. XRF030824: Second-epoch Palomar observations
  76. IPN triangulation of GRB030822 (annulus)
  77. GRB030823: optical observations
  78. GRB030823: Palomar observations
  79. XRF030824: Palomar observations
  80. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  81. GRB030823: optical observation at Tokyo Tech
  82. RAPTOR observations of GRB030823
  83. IPN triangulation of GRB030821 (=H2814; refined error box)
  84. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  85. Summary of recent IPN and HETE detections of SGR bursts
  86. IPN triangulation of GRB030814 (annulus)
  87. Clarification of GCN 2354 on SGR1806-20
  88. IPN detection of continued activity from SGR1806-20
  89. 030813 SGR event (Konus-Wind observation)
  90. GRB 030817 = H2808 TAROT optical observations
  91. SGR 1808-20 (=H2802): A Possible new SGR
  92. GRB 021206 Optical Observations
  93. IPN triangulation of GRB030808 (two large error boxes)
  94. IPN triangulation of GRB030806 (large burst; large error box)
  95. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  96. IPN/HETE summary of recent bursts from SGR1806-20
  97. XRF 030723: Detection of a rebrightening in the optical afterglow
  98. GRB030725: Optical observations
  99. XRF030723, BVRcIc field photometry update
  100. IPN triangulation of GRB030801 (large error box)

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