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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28052 results found.

  1. GRB050824: MASTER final analysis of the OT observations
  2. Swift-BAT trigger 152038 is probably not a GRB
  3. GRB 050824: XRT refined analysis and possible afterglow detection
  4. GRB 050824: BAT refined analysis of a soft weak burst
  5. GRB050824: MASTER:OT decay
  6. GRB050824: MASTER observation OT
  7. GRB050805a: MASTER optical candidat
  8. XRF050509c: Radio upper limits from GMRT
  9. GRB050822: Swift/UVOT upper limits
  10. GRB 050820A BAT observations of second, larger episode of emission
  11. GRB050813: Maidanak I-band observations
  12. GRB 050822: Swift-BAT refined analysis
  13. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  14. GRB050820B at FRAM
  15. Swift/UVOT UV Photometry of GRB 050820B
  16. GRB 050822: Swift detection of a long burst
  17. GRB050820a BVRcIc field photometry
  18. GRB050820B XMM-Newton observation
  19. GRB 050820a: NIR Observations by WIRO
  20. GRB 050820B: Swift XRT position
  21. GRB050820B: Refined analysis of the Swift-BAT burst
  22. GRB050820: refined XRT analysis
  23. GRB 050820 Swift-BAT refined analysis
  24. GRB050819: refined XRT analysis
  25. GRB 050820: Swift detection of a GRB
  26. GRB 050819 Swift-BAT refined analysis
  27. GRB050819: Swift-BAT detection of a weak burst
  28. GRB 050817: Optical observations
  29. GRB050817: Negative Optical Observations
  30. GRB 050814: continued fading
  31. GRB050815: Optical afterglow detection by Swift UVOT
  32. GRB050815: XRT refined analysis
  33. GRB050815: Refined analysis of the Swift-BAT burst
  34. GRB 050815: ROTSE-III Optical Limits
  35. GRB050815: Swift-BAT detection of a burst
  36. GRB050814: Fading red source
  37. GRB050814: P60 Optical Afterglow Candidate
  38. GRB 050813: Non-fading of afterglow candidate
  39. GRB 050814: XRT refined analysis
  40. GRB050814: SWIFT/UVOT observation
  41. GRB050814: Refined analysis of the Swift-BAT burst
  42. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  43. GRB 050814: Swift XRT Afterglow Localization
  44. GRB 050814: Swift detection of a burst
  45. GRB 050813: Magellan detection of a high redshift galaxy cluster
  46. GRB050813, SDSS pre-burst observations
  47. GRB 050813: Swift-BAT refined analysis
  48. GRB 050813: Photometry of object in XRT error circle
  49. GRB050813: SWIFT/UVOT observation
  50. GRB 050813: Swift XRT afterglow localization
  51. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  52. Detection of an intermediate burst from SGR 1806-20 on August 8
  53. GRB050805b: CrAO optical limit
  54. GRB050803, optical observations
  55. Retraction of Swift Trigger 149131 (GRB 050805B)
  56. GRB 050805b: OHP optical limits
  57. GRB 050805b: TAROT optical limits
  58. GRB050805b: MASTER optical observations
  59. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  60. GRB050805a: MASTER optical candidat
  61. GRB050802: TNG optical observations
  62. GRB050803: Radio Observation
  63. GRB 050803: RTT150 optical observations
  64. GRB050801: Radio Observation
  65. GRB050730: Radio Detection
  66. GRB 050803: Keck Observations
  67. GRB 050803: Swift-BAT refined analysis
  68. GRB 050802.422: Fading of the afterglow and detection of the host
  69. GRB 050803: early Swift XRT analysis results
  70. GRB 050803: TAROT optical limits
  71. GCN GRB observation 050713A
  72. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  73. GRB050802 radio non-detection
  74. GRB 050730: OHP optical observations
  75. GRB 050802: early Swift XRT analysis results
  76. GRB 050802: Swift/UVOT observations
  77. GRB 050802: Swift-BAT refined analysis
  78. GRB050801: Optical photometry and decay index
  79. GRB 050802: Swift Gamma-ray Burst
  80. GRB050801: Swift/UVOT Optical and UV detections
  81. GRB 050730: Preliminary Analysis of MIKE Spectrum
  82. GCN 050801: early Swift XRT analysis results
  83. GRB 050801: Swift-BAT refined analysis
  84. GRB 050730: XRT refined analysis
  85. GRB 050730: early TAROT optical observations
  86. GRB 050730, spectra and optical photometry
  87. GRB050730: Refined BAT analysis of the Swift-BAT burst
  88. GRB 050730 XMM-Newton observation
  89. GRB050730: Swift-BAT detection of a weak burst
  90. GRB050713b: Maidanak optical observations
  91. GRB 050724: Secure Host Redshift from Keck
  92. GRB 050724: WHT optical observations
  93. GRB050713: analysis of the XMM-Newton observation
  94. Swift-BAT trigger 147918 is not a real GRB
  95. GRB050724: VLT observations of the variable source
  96. GRB050709: Second Epoch Chandra Observation
  97. GRB050726: Swift-BAT detection of a weak burst
  98. GRB 050724: Optical Variability in Nearby Galaxy
  99. GRB 050724: J-band observations
  100. GRB 050724: GMOS Imaging and Spectroscopy

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