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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"

28117 results found.

  1. GRB031111, optical observations
  2. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  3. GRB031203: Chandra Observations
  4. GRB040106: refined X-ray transient position
  5. SN 2003dh/GRB030329 late-time optical spectroscopy
  6. GRB 031220: Optical observations of Chandra X-ray sources
  7. XMM-Newton Images of GRB 040106
  8. GRB031220: observation at Univercity of Miyazaki
  9. XMM-Newton observation of GRB040106
  10. GRB 040106 : peak flux
  11. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  12. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  13. GRB031220: Palomar Observations
  14. GRB 031220 : Kyoto Optical Observation
  15. GRB 031220: Subaru observation
  16. GRB 031220: Optical observation at Tokyo Tech
  17. GRB 2974 follow-up observations
  18. GRB031203, improved XMM position
  19. GRB 021203: A Normal GRB viewed far off axis?
  20. XMM-Newton Observations of GRB031203: Preliminary Images
  21. GRB 031203: Variable Radio Source
  22. GRB 031203: Magellan spectrum of possible GRB host
  23. GRB 031203: Optical/IR Astrometry
  24. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  25. XMM-Newton Observation of GRB031203
  26. GRB031203: K' Photometry of the likely GRB host
  27. XMM-Newton Observation of GRB031203
  28. GRB 031203: IR NTTobservations do not confirm REM detection
  29. GRB031203 : Optical Observation of Lulin Observatory
  30. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  31. GRB 031203: Apparent Spectral Break
  32. GRB031203: Planned XMM-Newton observation II
  33. GRB 031203: IR REM Observations
  34. GRB031203: Optical Observations
  35. GRB 031203 XMM-Newton observation
  36. GRB031203: Planned XMM-Newton observation
  37. GRB 031203: further analysis of INTEGRAL data
  38. GRB 030329: Planned XMM-Newton Observation
  39. GRB 031111B (= H2925) : Kyoto Optical Observation
  40. IPN triangulation of GRB031114 (large error box)
  41. GRB 031111, optical observations
  42. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  43. GRB030929/SN2003jd association unlikely based on IPN localiztion
  44. IPN triangulation of GRB031027 (small error box)
  45. Lulin optical follow-up observations of GRB031026
  46. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  47. IPN triangulation of GRB031024 (single error box)
  48. IPN triangulation of GRB031024 (annulus)
  49. IPN triangulation of GRB031020 (large error box)
  50. XRF 030824: additional observations at CFHT
  51. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  52. XRF 030723: Subaru Optical Observations
  53. XRF 030824: Early follow-up observation at Kiso observatory
  54. XRF 030824: observations at CFHT
  55. IPN triangulation of GRB030922B (large error box)
  56. XRF 030723: Detection of the likely host galaxy
  57. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  58. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  59. IPN triangulation of GRB030921 (large error box)
  60. IPN triangulation of GRB030919 (large error box)
  61. GRB030913: Subaru Optical Observations
  62. GRB 030913, optical candidate
  63. GRB 030913, BOOTES observations
  64. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  65. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  66. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  67. XRF030824: Optical observations
  68. IPN triangulation of GRB030903 (large error box)
  69. IPN triangulation of GRB030827 (large error box)
  70. GRB030823: optical observations
  71. GRB030823: optical observation at Tokyo Tech
  72. Lulin follow-up observations of GRB030823
  73. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  74. IPN detection of continued activity from SGR1806-20
  75. GRB 030817 = H2808 TAROT optical observations
  76. SGR 1808-20 (=H2802): A Possible new SGR
  77. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  78. XRF 030723: Detection of a rebrightening in the optical afterglow
  79. XRF030723, BVRcIc field photometry update
  80. IPN triangulation of GRB030801 (large error box)
  81. GRB021206 optical counterpart upper limit
  82. IPN triangulation of GRB030726 (large error box)
  83. IPN triangulation of GRB030721 (large error box)
  84. XRF030723 Radio Observations
  85. XRF 030723: confirmation of fading optical counterpart
  86. XRF030723(=H2777): Chandra Observations
  87. GRB030723: Upper limits from historical observations
  88. XRF030723: Palomar observations and proposed counterpart
  89. GRB030725 (=H2779): A Bright GRB Localized by HETE
  90. XRF030723 (= H2777): Chandra Observations Scheduled
  91. XRF030723, BVRcIc field photometry correction
  92. XRF030723, ROTSE-III Early Observations
  93. XRF030723, BVRcIc field photometry
  94. XRF 030723, optical observations
  95. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  96. Konus-Wind detection of the bursts from SGR1806-20 region
  97. SGR 1806-20, submm observations
  98. RXTE PCA Observations of SGR1806-20 Region
  99. IPN triangulation of GRB030714 (two large error boxes)
  100. IPN triangulation of GRB030715 (two large error boxes)

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