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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"

4714 results found.

  1. GRB 060203: P60 Confirmation of Optical Afterglow
  2. GRB 060202: Gemini-N J, H, K_s observations
  3. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  4. GRB 060121: I-band Limits
  5. GRB060121: SARA Observations
  6. GRB 060117: PROMPT Observations
  7. GRB 060116: PROMPT Observations
  8. GRB 060115: PROMPT Observations
  9. GRB 060114: Swift/UVOT Observations
  10. GRB 060115: MITSuME optical afterglow candidate
  11. GRB060111A: RTT150 optical observations
  12. GRB 060110: Optical limit
  13. Swift-BAT trigger 175653 is not an astrophysical source
  14. Swift-BAT trigger 175653 is probably not a GRB
  15. GRB 051227: MDM Observation
  16. Swift-BAT detection of a possible burst
  17. GRB 051221: Improved astrometry of the IR counterpart
  18. GRB051211b: P60 Observations
  19. Possible resuming of the SGR 1806-20 activity
  20. GRB 051117B,optical observation
  21. GRB 051111: Keck HIRES redshift
  22. GRB051111: Swift-BAT detection of a bright burst
  23. GRB051109B: no UVOT source detected
  24. GRB 051109B: Swift detection of a burst
  25. GRB 051109: HET Optical Spectrum and Absorption Redshift
  26. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  27. GRB051105B: Swift/XRT upper limit
  28. GRB051103: MASTER: OT limit and host galaxy candidates
  29. GRB051103:_MASTER_optical_observations
  30. GRB051028:MASTER observations
  31. GRB051021.63
  32. Swift-BAT trigger 160640 is not a real GRB
  33. GRB051021: A GRB Localized by HETE
  34. GRB050925: Swift UVOT upper limits
  35. GRB 050916: XRT position
  36. Swift is in normal operation
  37. GRB 050906: Possible X-ray Counterpart
  38. GRB 050906: Radio Observations
  39. GRB050904: Optical Observations
  40. Swift-BAT triggers 153461-153465 are not GRBs
  41. Retraction of Swift-BAT trigger #153355
  42. GRB050827: Swift-BAT detection of a burst
  43. GRB050822: Swift/UVOT upper limits
  44. GRB 050822: Swift-BAT refined analysis
  45. GRB 050822: ROTSE-III Prompt Optical Limits
  46. GRB 050822: Swift detection of a long burst
  47. GRB050820B: Planned XMM-Newton observation
  48. GRB050820B: BAT-Swift detection of a bright GRB
  49. GRB050813, SDSS pre-burst observations
  50. RBO GRB 050714A and GRB 050716 observations
  51. GRB050730: Radio Detection
  52. GRB 050730, corrected photometry and break?
  53. GRB050801: Swift-BAT detection of a burst
  54. GRB 050730, spectra and optical photometry
  55. GRB 050730: Swift XRT afterglow observations
  56. GRB050730, afterglow observations
  57. GRB 050730 : Planned XMM-Newton observation
  58. GRB050730: Liverpool Telescope optical observations
  59. GRB 050730, optical candidate
  60. GRB 050724, SMARTS optical/IR afterglow observations
  61. GRB050726: Swift-BAT detection of a weak burst
  62. GRB 050715: Swift-BAT detection
  63. Swift detection of a long transient (GRB 050714B?)
  64. GRB 050712: Swift XRT afterglow position
  65. GRB 050712: Swift detection of a weak burst
  66. GRB 050626: Swift XRT observations
  67. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  68. GRB 050626 - a long GRB detected with INTEGRAL
  69. GRB 050603: INTEGRAL shows it is not a short GRB
  70. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  71. GRB 050525: MITSuME Optical Observation in VRI
  72. GRB 050525A: BOOTES simultaneous optical observations
  73. GRB050525: Optical observations
  74. XRF 050522: Swift XRT refined analysis
  75. RBO Observations of GRB050520
  76. GRB 050505: SARA Observations
  77. GRB 050502a: Swift XRT Upper Limit
  78. GRB 050416: Swift/UVOT detection of afterglow emission
  79. GRB050416: Refined Swift-XRT analysis
  80. GRB 050416: Swift XRT Position
  81. GRB050416: P60 Afterglow Candidate
  82. GRB 050412: Subaru observations
  83. GRB 050412: optical limit
  84. GRB 050412: Swift-BAT refined analysis
  85. GRB 050412: Swift XRT Position
  86. Swift-BAT Detection of GRB 050412: A Bright, Long Burst
  87. GRB 050408, SMARTS optical/IR afterglow observations
  88. GRB 050408: Swift XRT Position
  89. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  90. GRB050401, radio observation at 4.8 GHz and 8.64 GHz
  91. GRB050331: No Afterglow Detected
  92. Swift-BAT detection of a bright outburst from SGR1806-20
  93. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  94. GRB 050318: Swift/UVOT detection of afterglow emission
  95. GRB 050318: Magellan optical afterglow identification
  96. GRB050318: Swift XRT position
  97. GRB050223: analysis of the XMM-Newton observation
  98. GRB050316: MASTER before, simultanious and follow up optical
  99. GRB 050306: ROTSE-III early limits
  100. GRB 050315, SMARTS optical/IR afterglow observations

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