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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"

24950 results found.

  1. GRB 040423 (=H3175): A Long GRB Localized by HETE
  2. GRB040422 : I-band follow-up observation at Lulin Observatory
  3. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  4. GRB040422, BVRcIc field calibration
  5. GRB 040422,optical observation
  6. GRB 040422: a long GRB detected with INTEGRAL
  7. GRB 040403, deep optical observations
  8. MASTER: HETE Alert 3163, 3167 technical optical observation
  9. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  10. GRB 040403: Optical observations
  11. GRB 040403: a long GRB detected with INTEGRAL
  12. GRB040323: NIR Observations and Variable Object
  13. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  14. GRB 040323, a dark GRB ?
  15. GRB 040323: a long GRB detected with INTEGRAL
  16. GRB040223: Deep NIR NTT data re-analysis
  17. GRB 040223: XMM-Newton results
  18. GRB040223, improved XMM position
  19. GRB 031203, possible supernova
  20. MASTER: RXTE GRB040308 optical observation
  21. IBAS results on a burst from SGR1806-20
  22. INTEGRAL detection of activity from SGR1806-20
  23. RXTE GRB040229 optical observation: no candidate
  24. GRB 040228 Optical observations
  25. GRB040228 : KISO optical follow-up observation
  26. GRB 040223: Deep NIR NTT observations
  27. GRB 040223 : Optical observation (non-detection)
  28. XMM-Newton Images of GRB 040223
  29. GRB 040223, VLA observations
  30. GRB 040223: REM IJK Observations
  31. GRB 040223 XMM-Newton observation ...
  32. GRB 031203 XMM-Newton observation
  33. GRB 040223: further offline analysis
  34. GRB031111, optical observations
  35. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  36. GRB031203: Chandra Observations
  37. GRB040106: refined X-ray transient position
  38. SN 2003dh/GRB030329 late-time optical spectroscopy
  39. GRB 031220: Optical observations of Chandra X-ray sources
  40. XMM-Newton Images of GRB 040106
  41. GRB031220: observation at Univercity of Miyazaki
  42. XMM-Newton observation of GRB040106
  43. GRB 040106 : peak flux
  44. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  45. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  46. GRB031220: Palomar Observations
  47. GRB 031220 : Kyoto Optical Observation
  48. GRB 031220: Subaru observation
  49. GRB 031220: Optical observation at Tokyo Tech
  50. GRB 2974 follow-up observations
  51. GRB031203, improved XMM position
  52. GRB 021203: A Normal GRB viewed far off axis?
  53. XMM-Newton Observations of GRB031203: Preliminary Images
  54. GRB 031203: Variable Radio Source
  55. GRB 031203: Magellan spectrum of possible GRB host
  56. GRB 031203: Optical/IR Astrometry
  57. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  58. XMM-Newton Observation of GRB031203
  59. GRB031203: K' Photometry of the likely GRB host
  60. XMM-Newton Observation of GRB031203
  61. GRB 031203: IR NTTobservations do not confirm REM detection
  62. GRB031203 : Optical Observation of Lulin Observatory
  63. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  64. GRB 031203: Apparent Spectral Break
  65. GRB031203: Planned XMM-Newton observation II
  66. GRB 031203: IR REM Observations
  67. GRB031203: Optical Observations
  68. GRB 031203 XMM-Newton observation
  69. GRB031203: Planned XMM-Newton observation
  70. GRB 031203: further analysis of INTEGRAL data
  71. GRB 030329: Planned XMM-Newton Observation
  72. GRB 031111B (= H2925) : Kyoto Optical Observation
  73. IPN triangulation of GRB031114 (large error box)
  74. GRB 031111, optical observations
  75. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  76. GRB030929/SN2003jd association unlikely based on IPN localiztion
  77. IPN triangulation of GRB031027 (small error box)
  78. Lulin optical follow-up observations of GRB031026
  79. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  80. IPN triangulation of GRB031024 (single error box)
  81. IPN triangulation of GRB031024 (annulus)
  82. IPN triangulation of GRB031020 (large error box)
  83. XRF 030824: additional observations at CFHT
  84. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  85. XRF 030723: Subaru Optical Observations
  86. XRF 030824: Early follow-up observation at Kiso observatory
  87. XRF 030824: observations at CFHT
  88. IPN triangulation of GRB030922B (large error box)
  89. XRF 030723: Detection of the likely host galaxy
  90. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  91. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  92. IPN triangulation of GRB030921 (large error box)
  93. IPN triangulation of GRB030919 (large error box)
  94. GRB030913: Subaru Optical Observations
  95. GRB 030913, optical candidate
  96. GRB 030913, BOOTES observations
  97. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  98. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  99. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  100. XRF030824: Optical observations

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