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"

26353 results found.

  1. GRB050826: Swift-BAT detection of a long burst
  2. GRB050824: MASTER final analysis of the OT observations
  3. Swift-BAT trigger 152038 is probably not a GRB
  4. GRB 050824: XRT refined analysis and possible afterglow detection
  5. GRB 050824: BAT refined analysis of a soft weak burst
  6. GRB050824: MASTER:OT decay
  7. GRB050824: MASTER observation OT
  8. GRB050805a: MASTER optical candidat
  9. XRF050509c: Radio upper limits from GMRT
  10. GRB050822: Swift/UVOT upper limits
  11. GRB 050820A BAT observations of second, larger episode of emission
  12. GRB050813: Maidanak I-band observations
  13. GRB 050822: Swift-BAT refined analysis
  14. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  15. GRB050820B at FRAM
  16. Swift/UVOT UV Photometry of GRB 050820B
  17. GRB 050822: Swift detection of a long burst
  18. GRB050820a BVRcIc field photometry
  19. GRB050820B XMM-Newton observation
  20. GRB 050820a: NIR Observations by WIRO
  21. GRB 050820B: Swift XRT position
  22. GRB050820B: Refined analysis of the Swift-BAT burst
  23. GRB050820: refined XRT analysis
  24. GRB 050820 Swift-BAT refined analysis
  25. GRB050819: refined XRT analysis
  26. GRB 050820: Swift detection of a GRB
  27. GRB 050819 Swift-BAT refined analysis
  28. GRB050819: Swift-BAT detection of a weak burst
  29. GRB 050817: Optical observations
  30. GRB050817: Negative Optical Observations
  31. GRB 050814: continued fading
  32. GRB050815: Optical afterglow detection by Swift UVOT
  33. GRB050815: XRT refined analysis
  34. GRB050815: Refined analysis of the Swift-BAT burst
  35. GRB 050815: ROTSE-III Optical Limits
  36. GRB050815: Swift-BAT detection of a burst
  37. GRB050814: Fading red source
  38. GRB050814: P60 Optical Afterglow Candidate
  39. GRB 050813: Non-fading of afterglow candidate
  40. GRB 050814: XRT refined analysis
  41. GRB050814: SWIFT/UVOT observation
  42. GRB050814: Refined analysis of the Swift-BAT burst
  43. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  44. GRB 050814: Swift XRT Afterglow Localization
  45. GRB 050814: Swift detection of a burst
  46. GRB 050813: Magellan detection of a high redshift galaxy cluster
  47. GRB050813, SDSS pre-burst observations
  48. GRB 050813: Swift-BAT refined analysis
  49. GRB 050813: Photometry of object in XRT error circle
  50. GRB050813: SWIFT/UVOT observation
  51. GRB 050813: Swift XRT afterglow localization
  52. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  53. Detection of an intermediate burst from SGR 1806-20 on August 8
  54. GRB050805b: CrAO optical limit
  55. GRB050803, optical observations
  56. Retraction of Swift Trigger 149131 (GRB 050805B)
  57. GRB 050805b: OHP optical limits
  58. GRB 050805b: TAROT optical limits
  59. GRB050805b: MASTER optical observations
  60. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  61. GRB050805a: MASTER optical candidat
  62. GRB050802: TNG optical observations
  63. GRB050803: Radio Observation
  64. GRB 050803: RTT150 optical observations
  65. GRB050801: Radio Observation
  66. GRB050730: Radio Detection
  67. GRB 050803: Keck Observations
  68. GRB 050803: Swift-BAT refined analysis
  69. GRB 050802.422: Fading of the afterglow and detection of the host
  70. GRB 050803: early Swift XRT analysis results
  71. GRB 050803: TAROT optical limits
  72. GCN GRB observation 050713A
  73. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  74. GRB050802 radio non-detection
  75. GRB 050730: OHP optical observations
  76. GRB 050802: early Swift XRT analysis results
  77. GRB 050802: Swift/UVOT observations
  78. GRB 050802: Swift-BAT refined analysis
  79. GRB050801: Optical photometry and decay index
  80. GRB 050802: Swift Gamma-ray Burst
  81. GRB050801: Swift/UVOT Optical and UV detections
  82. GRB 050730: Preliminary Analysis of MIKE Spectrum
  83. GCN 050801: early Swift XRT analysis results
  84. GRB 050801: Swift-BAT refined analysis
  85. GRB 050730: XRT refined analysis
  86. GRB 050730: early TAROT optical observations
  87. GRB 050730, spectra and optical photometry
  88. GRB050730: Refined BAT analysis of the Swift-BAT burst
  89. GRB 050730 XMM-Newton observation
  90. GRB050730: Swift-BAT detection of a weak burst
  91. GRB050713b: Maidanak optical observations
  92. GRB 050724: Secure Host Redshift from Keck
  93. GRB 050724: WHT optical observations
  94. GRB050713: analysis of the XMM-Newton observation
  95. Swift-BAT trigger 147918 is not a real GRB
  96. GRB050724: VLT observations of the variable source
  97. GRB050709: Second Epoch Chandra Observation
  98. GRB050726: Swift-BAT detection of a weak burst
  99. GRB 050724: Optical Variability in Nearby Galaxy
  100. GRB 050724: J-band observations

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