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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"

23410 results found.

  1. GRB 031203: IR NTTobservations do not confirm REM detection
  2. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  3. GRB 031203: Apparent Spectral Break
  4. GRB031203: Planned XMM-Newton observation II
  5. GRB 031203: IR REM Observations
  6. GRB031203: Optical Observations
  7. GRB 031203 XMM-Newton observation
  8. GRB 031203: Optical/IR SMARTS Observations
  9. GRB031203: Planned XMM-Newton observation
  10. IPN triangulation of GRB031127A and B (quasi-simultaneous; large error boxes)
  11. IPN triangulation of GRB031201 (large error box)
  12. IPN triangulation of GRB031130 (large error box)
  13. GRB 030329: Planned XMM-Newton Observation
  14. IPN triangulation of GRB031120 (two large error boxes)
  15. GRB 031111B (= H2925) : Kyoto Optical Observation
  16. IPN detection of activity from SGR1806-20
  17. IPN triangulation of GRB031114 (large error box)
  18. IPN triangulation of GRB031107 (two large error boxes)
  19. GRB 031111, optical observations
  20. IPN triangulation of GRB031111 (=H2924): small error box
  21. IPN triangulation of GRB031108 (large error box)
  22. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  23. GRB030929/SN2003jd association unlikely based on IPN localiztion
  24. IPN triangulation of GRB031027 (small error box)
  25. IPN triangulation of GRB031026B (large error box)
  26. Lulin optical follow-up observations of GRB031026
  27. SN 2003jd (SN/GRB?), Radio Observations
  28. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  29. GRB 031026: Further Ic Observations
  30. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  31. IPN triangulation of GRB031024 (single error box)
  32. GRB031026 : KISO optical follow-up observation
  33. IPN triangulation of GRB031024 (annulus)
  34. IPN triangulation of GRB031020 (large error box)
  35. GRB030329: radio observations at RT-22 (CrAO)
  36. IPN triangulation of GRB031016 (two large error boxes)
  37. IPN triangulation of GRB031014 (annulus)
  38. XRF 030824: additional observations at CFHT
  39. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  40. IPN triangulation of GRB031008 (annulus)
  41. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  42. IPN detection of continued activity from SGR1806-20
  43. IPN triangulation of GRB031007 (two large error boxes)
  44. XRF 030723: Subaru Optical Observations
  45. IPN triangulation of GRB031004B (annulus)
  46. IPN triangulation of GRB030929 (short/hard; annulus)
  47. XRF 030824: Early follow-up observation at Kiso observatory
  48. IPN triangulation of GRB030926 (short/hard; large error box)
  49. IPN triangulation of GRB030922B (large error box)
  50. XRF 030723: Detection of the likely host galaxy
  51. IPN triangulation of GRB030922A (large error box)
  52. IPN triangulation of GRB030921 (large error box)
  53. IPN triangulation of GRB030919 (large error box)
  54. GRB030922 triangulation (annulus)
  55. GRB030913: Subaru Optical Observations
  56. GRB030913: OT's limit by MASTER
  57. GRB030921 triangulation (annulus)
  58. GRB 030913, optical candidate
  59. GRB 030913, BOOTES observations
  60. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  61. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  62. IPN triangulation of GRB030908 (annulus)
  63. XRF030824: Optical observations
  64. IPN triangulation of GRB030903 (large error box)
  65. IBAS detection of bursts from SGR 1806-20
  66. IPN triangulation of GRB030831 (annulus)
  67. IPN triangulation of GRB030830 (large error box)
  68. IPN triangulation of GRB030827 (large error box)
  69. IPN triangulation of GRB030822 (annulus)
  70. GRB030823: optical observations
  71. GRB030823: optical observation at Tokyo Tech
  72. Lulin follow-up observations of GRB030823
  73. IPN triangulation of GRB030821 (=H2814; refined error box)
  74. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  75. IPN triangulation of GRB030814 (annulus)
  76. IPN detection of continued activity from SGR1806-20
  77. GRB 030817 = H2808 TAROT optical observations
  78. SGR 1808-20 (=H2802): A Possible new SGR
  79. IPN triangulation of GRB030808 (two large error boxes)
  80. IPN triangulation of GRB030806 (large burst; large error box)
  81. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  82. XRF030723, BVRcIc field photometry update
  83. IPN triangulation of GRB030801 (large error box)
  84. GRB021206 optical counterpart upper limit
  85. IPN triangulation of GRB030731 (annulus)
  86. IPN triangulation of GRB030725 (=H2779; small error box)
  87. IPN triangulation of GRB030726 (large error box)
  88. IPN triangulation of GRB030722 (large error box)
  89. IPN triangulation of GRB030721 (large error box)
  90. XRF030723 Radio Observations
  91. XRF 030723: confirmation of fading optical counterpart
  92. XRF030723(=H2777): Chandra Observations
  93. GRB030723: Upper limits from historical observations
  94. XRF030723: Palomar observations and proposed counterpart
  95. XRF030723, BVRcIc field photometry correction
  96. XRF030723, ROTSE-III Early Observations
  97. XRF030723, BVRcIc field photometry
  98. XRF 030723, optical observations
  99. XRF 030723, optical observations
  100. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and

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