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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"

28054 results found.

  1. GRB 040511: Optical Observations
  2. GRB040511: Optical Observations
  3. GRB040511: Optical Observations
  4. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  5. GRB 040423 (=H3175): A Long GRB Localized by HETE
  6. GRB040422 : I-band follow-up observation at Lulin Observatory
  7. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  8. GRB040422, BVRcIc field calibration
  9. GRB 040422,optical observation
  10. GRB 040422: a long GRB detected with INTEGRAL
  11. GRB 040403, deep optical observations
  12. MASTER: HETE Alert 3163, 3167 technical optical observation
  13. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  14. GRB 040403: Optical observations
  15. GRB 040403: a long GRB detected with INTEGRAL
  16. GRB040323: NIR Observations and Variable Object
  17. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  18. GRB 040323, a dark GRB ?
  19. GRB 040323: a long GRB detected with INTEGRAL
  20. GRB040223: Deep NIR NTT data re-analysis
  21. GRB 040223: XMM-Newton results
  22. GRB040223, improved XMM position
  23. GRB 031203, possible supernova
  24. MASTER: RXTE GRB040308 optical observation
  25. IBAS results on a burst from SGR1806-20
  26. INTEGRAL detection of activity from SGR1806-20
  27. RXTE GRB040229 optical observation: no candidate
  28. GRB 040228 Optical observations
  29. GRB040228 : KISO optical follow-up observation
  30. GRB 040223: Deep NIR NTT observations
  31. GRB 040223 : Optical observation (non-detection)
  32. XMM-Newton Images of GRB 040223
  33. GRB 040223, VLA observations
  34. GRB 040223: REM IJK Observations
  35. GRB 040223 XMM-Newton observation ...
  36. GRB 031203 XMM-Newton observation
  37. GRB 040223: further offline analysis
  38. GRB031111, optical observations
  39. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  40. GRB031203: Chandra Observations
  41. GRB040106: refined X-ray transient position
  42. SN 2003dh/GRB030329 late-time optical spectroscopy
  43. GRB 031220: Optical observations of Chandra X-ray sources
  44. XMM-Newton Images of GRB 040106
  45. GRB031220: observation at Univercity of Miyazaki
  46. XMM-Newton observation of GRB040106
  47. GRB 040106 : peak flux
  48. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  49. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  50. GRB031220: Palomar Observations
  51. GRB 031220 : Kyoto Optical Observation
  52. GRB 031220: Subaru observation
  53. GRB 031220: Optical observation at Tokyo Tech
  54. GRB 2974 follow-up observations
  55. GRB031203, improved XMM position
  56. GRB 021203: A Normal GRB viewed far off axis?
  57. XMM-Newton Observations of GRB031203: Preliminary Images
  58. GRB 031203: Variable Radio Source
  59. GRB 031203: Magellan spectrum of possible GRB host
  60. GRB 031203: Optical/IR Astrometry
  61. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  62. XMM-Newton Observation of GRB031203
  63. GRB031203: K' Photometry of the likely GRB host
  64. XMM-Newton Observation of GRB031203
  65. GRB 031203: IR NTTobservations do not confirm REM detection
  66. GRB031203 : Optical Observation of Lulin Observatory
  67. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  68. GRB 031203: Apparent Spectral Break
  69. GRB031203: Planned XMM-Newton observation II
  70. GRB 031203: IR REM Observations
  71. GRB031203: Optical Observations
  72. GRB 031203 XMM-Newton observation
  73. GRB031203: Planned XMM-Newton observation
  74. GRB 031203: further analysis of INTEGRAL data
  75. GRB 030329: Planned XMM-Newton Observation
  76. GRB 031111B (= H2925) : Kyoto Optical Observation
  77. IPN triangulation of GRB031114 (large error box)
  78. GRB 031111, optical observations
  79. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  80. GRB030929/SN2003jd association unlikely based on IPN localiztion
  81. IPN triangulation of GRB031027 (small error box)
  82. Lulin optical follow-up observations of GRB031026
  83. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  84. IPN triangulation of GRB031024 (single error box)
  85. IPN triangulation of GRB031024 (annulus)
  86. IPN triangulation of GRB031020 (large error box)
  87. XRF 030824: additional observations at CFHT
  88. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  89. XRF 030723: Subaru Optical Observations
  90. XRF 030824: Early follow-up observation at Kiso observatory
  91. XRF 030824: observations at CFHT
  92. IPN triangulation of GRB030922B (large error box)
  93. XRF 030723: Detection of the likely host galaxy
  94. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  95. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  96. IPN triangulation of GRB030921 (large error box)
  97. IPN triangulation of GRB030919 (large error box)
  98. GRB030913: Subaru Optical Observations
  99. GRB 030913, optical candidate
  100. GRB 030913, BOOTES observations

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