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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"

19499 results found.

  1. GRB 040606: Optical observations
  2. MASTER: HETE Alert 3274 optical observation
  3. Activivty of SGR 1806-20
  4. IPN triangulation of an intense intermediate burst from SGR1806-20
  5. GRB 040511, very fast decay?
  6. GRB 030324: Detection and Color of Host Galaxy
  7. GRB 040511: NIR observations with REM
  8. GRB040511: Candidate optical/NIR afterglow
  9. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  10. GRB 040511: Second Epoch Optical Observations
  11. GRB 040511: Optical observations
  12. GRB 040511: Optical Observations
  13. GRB040511: Optical Observations
  14. GRB040511: Optical Observations
  15. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  16. GRB 040423 (=H3175): A Long GRB Localized by HETE
  17. GRB040422 : I-band follow-up observation at Lulin Observatory
  18. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  19. GRB040422, BVRcIc field calibration
  20. GRB 040422,optical observation
  21. GRB 040403, deep optical observations
  22. MASTER: HETE Alert 3163, 3167 technical optical observation
  23. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  24. GRB 040403: Optical observations
  25. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  26. GRB040323: NIR Observations and Variable Object
  27. GRB 040323, a dark GRB ?
  28. short hard GRB 040322
  29. GRB040223, improved XMM position
  30. GRB 031203, possible supernova
  31. MASTER: RXTE GRB040308 optical observation
  32. IBAS results on a burst from SGR1806-20
  33. IPN triangulation of GRB040228 (H3066, H3067)
  34. GRB040228 : KISO optical follow-up observation
  35. GRB 040223: Deep NIR NTT observations
  36. GRB 040223 : Optical observation (non-detection)
  37. XMM-Newton Images of GRB 040223
  38. GRB 040223, VLA observations
  39. GRB 040223: REM IJK Observations
  40. GRB 040223 XMM-Newton observation ...
  41. GRB 031203 XMM-Newton observation
  42. GRB031111, optical observations
  43. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  44. GRB040106: refined X-ray transient position
  45. GRB040106, Radio Observations
  46. GRB040106, likely optical afterglow
  47. GRB 031220: Optical observations of Chandra X-ray sources
  48. XMM-Newton Images of GRB 040106
  49. GRB031220: observation at Univercity of Miyazaki
  50. XMM-Newton observation of GRB040106
  51. IPN triangulation of an intermediate burst from SGR1806-20
  52. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  53. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  54. GRB031220: Palomar Observations
  55. GRB 031220 : Kyoto Optical Observation
  56. GRB 031220: Subaru observation
  57. GRB 031220: Optical observation at Tokyo Tech
  58. GRB 2974 follow-up observations
  59. GRB031203, improved XMM position
  60. GRB 031203: SMARTS optical monitoring
  61. XMM-Newton Observations of GRB031203: Preliminary Images
  62. GRB 031203: Optical/IR Astrometry
  63. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  64. XMM-Newton Observation of GRB031203
  65. XMM-Newton Observation of GRB031203
  66. GRB 031203: IR NTTobservations do not confirm REM detection
  67. GRB031203 : Optical Observation of Lulin Observatory
  68. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  69. GRB031203: Planned XMM-Newton observation II
  70. GRB 031203: IR REM Observations
  71. GRB031203: Optical Observations
  72. GRB 031203 XMM-Newton observation
  73. GRB 031203: Optical/IR SMARTS Observations
  74. GRB031203: Planned XMM-Newton observation
  75. GRB 030329: Planned XMM-Newton Observation
  76. GRB 031111B (= H2925) : Kyoto Optical Observation
  77. GRB 031111, Radio observations
  78. IPN triangulation of GRB031114 (large error box)
  79. GRB 031111, optical observations
  80. IPN triangulation of GRB031108 (large error box)
  81. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  82. GRB030929/SN2003jd association unlikely based on IPN localiztion
  83. Lulin optical follow-up observations of GRB031026
  84. IPN triangulation of GRB031024 (single error box)
  85. IPN triangulation of GRB031024 (annulus)
  86. XRF 030824: additional observations at CFHT
  87. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  88. IPN triangulation of GRB031007 (two large error boxes)
  89. XRF 030723: Subaru Optical Observations
  90. XRF 030824: Early follow-up observation at Kiso observatory
  91. XRF 030723: Detection of the likely host galaxy
  92. IPN triangulation of GRB030921 (large error box)
  93. GRB030913: Subaru Optical Observations
  94. GRB 030913, optical candidate
  95. GRB 030913, BOOTES observations
  96. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  97. XRF030824: Optical observations
  98. IPN triangulation of GRB030827 (large error box)
  99. GRB030823: optical observation at Tokyo Tech
  100. Lulin follow-up observations of GRB030823

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