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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"

25034 results found.

  1. GRB 040223: XMM-Newton results
  2. GRB040223, improved XMM position
  3. GRB 031203, possible supernova
  4. MASTER: RXTE GRB040308 optical observation
  5. IBAS results on a burst from SGR1806-20
  6. INTEGRAL detection of activity from SGR1806-20
  7. RXTE GRB040229 optical observation: no candidate
  8. GRB 040228 Optical observations
  9. GRB040228 : KISO optical follow-up observation
  10. GRB 040223: Deep NIR NTT observations
  11. GRB 040223 : Optical observation (non-detection)
  12. XMM-Newton Images of GRB 040223
  13. GRB 040223, VLA observations
  14. GRB 040223: REM IJK Observations
  15. GRB 040223 XMM-Newton observation ...
  16. GRB 031203 XMM-Newton observation
  17. GRB 040223: further offline analysis
  18. GRB031111, optical observations
  19. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  20. GRB031203: Chandra Observations
  21. GRB040106: refined X-ray transient position
  22. SN 2003dh/GRB030329 late-time optical spectroscopy
  23. GRB 031220: Optical observations of Chandra X-ray sources
  24. XMM-Newton Images of GRB 040106
  25. GRB031220: observation at Univercity of Miyazaki
  26. XMM-Newton observation of GRB040106
  27. GRB 040106 : peak flux
  28. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  29. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  30. GRB031220: Palomar Observations
  31. GRB 031220 : Kyoto Optical Observation
  32. GRB 031220: Subaru observation
  33. GRB 031220: Optical observation at Tokyo Tech
  34. GRB 2974 follow-up observations
  35. GRB031203, improved XMM position
  36. GRB 021203: A Normal GRB viewed far off axis?
  37. XMM-Newton Observations of GRB031203: Preliminary Images
  38. GRB 031203: Variable Radio Source
  39. GRB 031203: Magellan spectrum of possible GRB host
  40. GRB 031203: Optical/IR Astrometry
  41. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  42. XMM-Newton Observation of GRB031203
  43. GRB031203: K' Photometry of the likely GRB host
  44. XMM-Newton Observation of GRB031203
  45. GRB 031203: IR NTTobservations do not confirm REM detection
  46. GRB031203 : Optical Observation of Lulin Observatory
  47. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  48. GRB 031203: Apparent Spectral Break
  49. GRB031203: Planned XMM-Newton observation II
  50. GRB 031203: IR REM Observations
  51. GRB031203: Optical Observations
  52. GRB 031203 XMM-Newton observation
  53. GRB031203: Planned XMM-Newton observation
  54. GRB 031203: further analysis of INTEGRAL data
  55. GRB 030329: Planned XMM-Newton Observation
  56. GRB 031111B (= H2925) : Kyoto Optical Observation
  57. IPN triangulation of GRB031114 (large error box)
  58. GRB 031111, optical observations
  59. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  60. GRB030929/SN2003jd association unlikely based on IPN localiztion
  61. IPN triangulation of GRB031027 (small error box)
  62. Lulin optical follow-up observations of GRB031026
  63. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  64. IPN triangulation of GRB031024 (single error box)
  65. IPN triangulation of GRB031024 (annulus)
  66. IPN triangulation of GRB031020 (large error box)
  67. XRF 030824: additional observations at CFHT
  68. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  69. XRF 030723: Subaru Optical Observations
  70. XRF 030824: Early follow-up observation at Kiso observatory
  71. XRF 030824: observations at CFHT
  72. IPN triangulation of GRB030922B (large error box)
  73. XRF 030723: Detection of the likely host galaxy
  74. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  75. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  76. IPN triangulation of GRB030921 (large error box)
  77. IPN triangulation of GRB030919 (large error box)
  78. GRB030913: Subaru Optical Observations
  79. GRB 030913, optical candidate
  80. GRB 030913, BOOTES observations
  81. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  82. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  83. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  84. XRF030824: Optical observations
  85. IPN triangulation of GRB030903 (large error box)
  86. IPN triangulation of GRB030827 (large error box)
  87. GRB030823: optical observations
  88. GRB030823: optical observation at Tokyo Tech
  89. Lulin follow-up observations of GRB030823
  90. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  91. IPN detection of continued activity from SGR1806-20
  92. GRB 030817 = H2808 TAROT optical observations
  93. SGR 1808-20 (=H2802): A Possible new SGR
  94. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  95. XRF 030723: Detection of a rebrightening in the optical afterglow
  96. XRF030723, BVRcIc field photometry update
  97. IPN triangulation of GRB030801 (large error box)
  98. GRB021206 optical counterpart upper limit
  99. IPN triangulation of GRB030726 (large error box)
  100. IPN triangulation of GRB030721 (large error box)

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