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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"

26342 results found.

  1. GRB050813: Maidanak I-band observations
  2. GRB 050822: Swift-BAT refined analysis
  3. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  4. GRB050820B at FRAM
  5. Swift/UVOT UV Photometry of GRB 050820B
  6. GRB 050822: Swift detection of a long burst
  7. GRB050820a BVRcIc field photometry
  8. GRB050820B XMM-Newton observation
  9. GRB 050820a: NIR Observations by WIRO
  10. GRB 050820B: Swift XRT position
  11. GRB050820B: Refined analysis of the Swift-BAT burst
  12. GRB050820: refined XRT analysis
  13. GRB 050820 Swift-BAT refined analysis
  14. GRB050819: refined XRT analysis
  15. GRB 050820: Swift detection of a GRB
  16. GRB 050819 Swift-BAT refined analysis
  17. GRB050819: Swift-BAT detection of a weak burst
  18. GRB 050817: Optical observations
  19. GRB050817: Negative Optical Observations
  20. GRB 050814: continued fading
  21. GRB050815: Optical afterglow detection by Swift UVOT
  22. GRB050815: XRT refined analysis
  23. GRB050815: Refined analysis of the Swift-BAT burst
  24. GRB 050815: ROTSE-III Optical Limits
  25. GRB050815: Swift-BAT detection of a burst
  26. GRB050814: Fading red source
  27. GRB050814: P60 Optical Afterglow Candidate
  28. GRB 050813: Non-fading of afterglow candidate
  29. GRB 050814: XRT refined analysis
  30. GRB050814: SWIFT/UVOT observation
  31. GRB050814: Refined analysis of the Swift-BAT burst
  32. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  33. GRB 050814: Swift XRT Afterglow Localization
  34. GRB 050814: Swift detection of a burst
  35. GRB 050813: Magellan detection of a high redshift galaxy cluster
  36. GRB050813, SDSS pre-burst observations
  37. GRB 050813: Swift-BAT refined analysis
  38. GRB 050813: Photometry of object in XRT error circle
  39. GRB050813: SWIFT/UVOT observation
  40. GRB 050813: Swift XRT afterglow localization
  41. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  42. Detection of an intermediate burst from SGR 1806-20 on August 8
  43. GRB050805b: CrAO optical limit
  44. GRB050803, optical observations
  45. Retraction of Swift Trigger 149131 (GRB 050805B)
  46. GRB 050805b: OHP optical limits
  47. GRB 050805b: TAROT optical limits
  48. GRB050805b: MASTER optical observations
  49. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  50. GRB050805a: MASTER optical candidat
  51. GRB050802: TNG optical observations
  52. GRB050803: Radio Observation
  53. GRB 050803: RTT150 optical observations
  54. GRB050801: Radio Observation
  55. GRB050730: Radio Detection
  56. GRB 050803: Keck Observations
  57. GRB 050803: Swift-BAT refined analysis
  58. GRB 050802.422: Fading of the afterglow and detection of the host
  59. GRB 050803: early Swift XRT analysis results
  60. GRB 050803: TAROT optical limits
  61. GCN GRB observation 050713A
  62. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  63. GRB050802 radio non-detection
  64. GRB 050730: OHP optical observations
  65. GRB 050802: early Swift XRT analysis results
  66. GRB 050802: Swift/UVOT observations
  67. GRB 050802: Swift-BAT refined analysis
  68. GRB050801: Optical photometry and decay index
  69. GRB 050802: Swift Gamma-ray Burst
  70. GRB050801: Swift/UVOT Optical and UV detections
  71. GRB 050730: Preliminary Analysis of MIKE Spectrum
  72. GCN 050801: early Swift XRT analysis results
  73. GRB 050801: Swift-BAT refined analysis
  74. GRB 050730: XRT refined analysis
  75. GRB 050730: early TAROT optical observations
  76. GRB 050730, spectra and optical photometry
  77. GRB050730: Refined BAT analysis of the Swift-BAT burst
  78. GRB 050730 XMM-Newton observation
  79. GRB050730: Swift-BAT detection of a weak burst
  80. GRB050713b: Maidanak optical observations
  81. GRB 050724: Secure Host Redshift from Keck
  82. GRB 050724: WHT optical observations
  83. GRB050713: analysis of the XMM-Newton observation
  84. Swift-BAT trigger 147918 is not a real GRB
  85. GRB050724: VLT observations of the variable source
  86. GRB050709: Second Epoch Chandra Observation
  87. GRB050726: Swift-BAT detection of a weak burst
  88. GRB 050724: Optical Variability in Nearby Galaxy
  89. GRB 050724: J-band observations
  90. GRB 050724: GMOS Imaging and Spectroscopy
  91. GRB050724: Radio Observation
  92. GRB 050724: Optical imaging/astrometry
  93. GRB 050724: Swift/UVOT Upper Limit
  94. GRB050724: Refined analysis of the Swift-BAT possible short burst
  95. GRB 050724: possible host galaxy in DSS
  96. GRB 050721A: Swift-BAT refined analysis
  97. GRB 050721A: Early Swift XRT analysis results
  98. GRB050721A: optical decay
  99. GRB 050721: optical afterglow confirmed
  100. GRB 050709: Refined Spectral and Temporal Properties

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