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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"

23417 results found.

  1. XRF040812: possible afterglow second Chandra observation
  2. GRB 040812: Second epoch CXO Observations
  3. GRB040823,optical observation
  4. XRF040812: GMRT observations
  5. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  6. XRF 040812: optical observation at VLT
  7. GRB 040812: Optical counterparts of CXO sources
  8. CXO observation of GRB 040812
  9. IPN/HETE localizations of GRB040810 (=H3489)
  10. GRB040812, optical/IR observations
  11. XRF040701: Optical Observations at ESO
  12. IPN/HETE triangulation of GRB040802 (=H3485)
  13. GRB 040730, infrared observations
  14. GRB 040730: Optical observations
  15. Ongoing activity of SGR 1806-20
  16. GRB040624: optical monitoring at TNG
  17. XRF 040701 - optical observations of the decaying Chandra source
  18. XRF040701: Second-Epoch Chandra Observations
  19. XRF040701: VLA Observations
  20. XRF040701: First-Epoch Chandra Observations
  21. GRB040624, optical observations
  22. GRB040706:observation at University of Miyazaki
  23. GRB 040624: optical observations
  24. Optical Observations of GRB040624
  25. GRB 040624: optical observations at TNG and VLT
  26. MASTER: GRB 040624 optical observation after 0,48d
  27. GRB 040624, optical observations
  28. GRB 040624 - A long GRB detected with INTEGRAL
  29. GRB 030329: Rebrightening of hyperluminal ejecta.
  30. IPN Summary of SGR1806-20 Activity in 2004
  31. SGR 1806-20: no IR variability of the proposed counterparts
  32. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  33. GRB 040606: Optical observations
  34. MASTER: HETE Alert 3274 optical observation
  35. Activivty of SGR 1806-20
  36. GRB 040511, very fast decay?
  37. GRB 030324: Detection and Color of Host Galaxy
  38. GRB 040511: NIR observations with REM
  39. GRB040511: Candidate optical/NIR afterglow
  40. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  41. GRB 040511: Second Epoch Optical Observations
  42. GRB 040511: Optical observations
  43. GRB 040511: Optical Observations
  44. GRB040511: Optical Observations
  45. GRB040511: Optical Observations
  46. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  47. IPN triangulation of GRB040425 (=H3183)
  48. GRB 040423 (=H3175): A Long GRB Localized by HETE
  49. GRB040422 : I-band follow-up observation at Lulin Observatory
  50. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  51. GRB040422, BVRcIc field calibration
  52. GRB 040422,optical observation
  53. GRB 040403, deep optical observations
  54. MASTER: HETE Alert 3163, 3167 technical optical observation
  55. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  56. GRB 040403: Optical Observations
  57. GRB 040403: Optical observations
  58. GRB 040403: optical observations
  59. GRB 040403: a long GRB detected with INTEGRAL
  60. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  61. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  62. GRB040323: NIR Observations and Variable Object
  63. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  64. GRB 040323, a dark GRB ?
  65. short hard GRB 040322
  66. GRB040223, improved XMM position
  67. GRB 031203, possible supernova
  68. MASTER: RXTE GRB040308 optical observation
  69. IBAS results on a burst from SGR1806-20
  70. RXTE GRB040229 optical observation: no candidate
  71. IPN triangulation of GRB040228 (H3066, H3067)
  72. GRB040228 : KISO optical follow-up observation
  73. GRB 040223: Deep NIR NTT observations
  74. GRB 040223 : Optical observation (non-detection)
  75. XMM-Newton Images of GRB 040223
  76. GRB 040223, VLA observations
  77. GRB 040223: REM IJK Observations
  78. GRB 040223 XMM-Newton observation ...
  79. GRB 031203 XMM-Newton observation
  80. GRB 040223: further offline analysis
  81. GRB031111, optical observations
  82. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  83. GRB040106: refined X-ray transient position
  84. GRB 031220: Optical observations of Chandra X-ray sources
  85. XMM-Newton Images of GRB 040106
  86. GRB031220: observation at Univercity of Miyazaki
  87. XMM-Newton observation of GRB040106
  88. GRB 040106 : a long GRB detected with INTEGRAL
  89. IPN triangulation of an intermediate burst from SGR1806-20
  90. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  91. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  92. GRB031225a triangulation (annulus)
  93. IPN triangulation of GRB031219 (large error box)
  94. GRB 031220 : Kyoto Optical Observation
  95. GRB 031220: Subaru observation
  96. GRB 031220: Optical observation at Tokyo Tech
  97. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  98. GRB 2974 follow-up observations
  99. GRB031203, improved XMM position
  100. GRB 031203: Discovery of a dust echo

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