Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. See news and announcements

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"

26421 results found.

  1. GRB050815: XRT refined analysis
  2. GRB050815: Refined analysis of the Swift-BAT burst
  3. GRB 050815: ROTSE-III Optical Limits
  4. GRB050815: Swift-BAT detection of a burst
  5. GRB050814: Fading red source
  6. GRB050814: P60 Optical Afterglow Candidate
  7. GRB 050813: Non-fading of afterglow candidate
  8. GRB 050814: XRT refined analysis
  9. GRB050814: SWIFT/UVOT observation
  10. GRB050814: Refined analysis of the Swift-BAT burst
  11. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  12. GRB 050814: Swift XRT Afterglow Localization
  13. GRB 050814: Swift detection of a burst
  14. GRB 050813: Magellan detection of a high redshift galaxy cluster
  15. GRB050813, SDSS pre-burst observations
  16. GRB 050813: Swift-BAT refined analysis
  17. GRB 050813: Photometry of object in XRT error circle
  18. GRB050813: SWIFT/UVOT observation
  19. GRB 050813: Swift XRT afterglow localization
  20. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  21. Detection of an intermediate burst from SGR 1806-20 on August 8
  22. GRB050805b: CrAO optical limit
  23. GRB050803, optical observations
  24. Retraction of Swift Trigger 149131 (GRB 050805B)
  25. GRB 050805b: OHP optical limits
  26. GRB 050805b: TAROT optical limits
  27. GRB050805b: MASTER optical observations
  28. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  29. GRB050805a: MASTER optical candidat
  30. GRB050802: TNG optical observations
  31. GRB050803: Radio Observation
  32. GRB 050803: RTT150 optical observations
  33. GRB050801: Radio Observation
  34. GRB050730: Radio Detection
  35. GRB 050803: Keck Observations
  36. GRB 050803: Swift-BAT refined analysis
  37. GRB 050802.422: Fading of the afterglow and detection of the host
  38. GRB 050803: early Swift XRT analysis results
  39. GRB 050803: TAROT optical limits
  40. GCN GRB observation 050713A
  41. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  42. GRB050802 radio non-detection
  43. GRB 050730: OHP optical observations
  44. GRB 050802: early Swift XRT analysis results
  45. GRB 050802: Swift/UVOT observations
  46. GRB 050802: Swift-BAT refined analysis
  47. GRB050801: Optical photometry and decay index
  48. GRB 050802: Swift Gamma-ray Burst
  49. GRB050801: Swift/UVOT Optical and UV detections
  50. GRB 050730: Preliminary Analysis of MIKE Spectrum
  51. GCN 050801: early Swift XRT analysis results
  52. GRB 050801: Swift-BAT refined analysis
  53. GRB 050730: XRT refined analysis
  54. GRB 050730: early TAROT optical observations
  55. GRB 050730, spectra and optical photometry
  56. GRB050730: Refined BAT analysis of the Swift-BAT burst
  57. GRB 050730 XMM-Newton observation
  58. GRB050730: Swift-BAT detection of a weak burst
  59. GRB050713b: Maidanak optical observations
  60. GRB 050724: Secure Host Redshift from Keck
  61. GRB 050724: WHT optical observations
  62. GRB050713: analysis of the XMM-Newton observation
  63. Swift-BAT trigger 147918 is not a real GRB
  64. GRB050724: VLT observations of the variable source
  65. GRB050709: Second Epoch Chandra Observation
  66. GRB050726: Swift-BAT detection of a weak burst
  67. GRB 050724: Optical Variability in Nearby Galaxy
  68. GRB 050724: J-band observations
  69. GRB 050724: GMOS Imaging and Spectroscopy
  70. GRB050724: Radio Observation
  71. GRB 050724: Optical imaging/astrometry
  72. GRB 050724: Swift/UVOT Upper Limit
  73. GRB050724: Refined analysis of the Swift-BAT possible short burst
  74. GRB 050724: possible host galaxy in DSS
  75. GRB 050721A: Swift-BAT refined analysis
  76. GRB 050721A: Early Swift XRT analysis results
  77. GRB050721A: optical decay
  78. GRB 050721: optical afterglow confirmed
  79. GRB 050709: Refined Spectral and Temporal Properties
  80. GRB050714b: Radio Observation
  81. GRB050712: Radio Observations
  82. GRB050713a: Radio Observation
  83. GRB 050712, Tautenburg optical afterglow observations
  84. Swift-BAT detection of a possible GRB
  85. GRB 050714B: VLT R-band observations
  86. GRB 050717: Additional LCO observations
  87. GRB 050716; J-band observations
  88. GRB 050717: LCO near-IR observations
  89. Swift/UVOT Observations of GRB 050717
  90. GRB 050717: Swift-BAT refined analysis
  91. GRB050717: Swift XRT position
  92. Swift detection of GRB 050717
  93. Swift UVOT Observations of GRB 050716
  94. GRB 050716: Refined XRT analysis.
  95. GRB050716: Refined analysis of the Swift-BAT burst
  96. GRB 050716: Lulin B and R band optical observations
  97. GRB050716, optical observation
  98. GRB050716: Faulkes North Telescope observation
  99. GRB050715: Refined analysis of the Swift-BAT burst
  100. GRB 050715: Swift-BAT detection

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov