Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

19857 results found.

  1. GRB 050713A: ROTSE-III Optical Limits
  2. GRB050709: Radio Observations
  3. GRB050712: UVOT candidate optical counterpart
  4. GRB 050712: Swift detection of a weak burst
  5. GRB 050709: LCO40 Observations
  6. PROMPT Rc Observations of GRB 050709
  7. GRB 050525a: PROMPT VRcIc Detections
  8. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  9. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  10. GRB 050626 optical observations
  11. GRB 050408: ARC 3.5-meter NIR Observations
  12. Swift UVOT observations of GRB 050701
  13. GRB 050607, radio observations
  14. GRB050525a: HST Observations
  15. XRF 050509c: Optical monitoring
  16. XRF050509c: Radio Detection
  17. GRB 050607 optical decay
  18. GRB050607: refined analysis of prompt REM observations
  19. GRB 050607: PROMPT VRcIc Observations
  20. GRB 050607: Optical decay and spectral slope
  21. GRB050607,optical observation
  22. Optical Afterglow of GRB 050607
  23. GRB050607: Swift Detection of a long GRB
  24. GRB050607: prompt REM observations
  25. Limits on a SN in the field of GRB 050509b
  26. GRB050603, submillimetre observations
  27. GRB050603: Radio Detection
  28. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  29. GRB 050603: Afterglow Identification from LCO
  30. GRB 050603: INTEGRAL shows it is not a short GRB
  31. Swift/BAT Detection of GRB050603
  32. GRB 050525a, infrared observations
  33. GRB050528: updated Liverpool Telescope limits
  34. Swift-BAT GRB 050528: a soft burst
  35. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  36. Possible GRB050528: no candidate from Liverpool Telescope
  37. Swift-BAT detection of possible GRB 050528
  38. GRB050525a: Radio Observations
  39. GRB 050509b: refined XRT/Chandra afterglow position analysis
  40. GRB 050525: RTT150, Optical observations
  41. GRB 050525a: SARA Observations
  42. GRB 050525B: Swift-BAT observations
  43. GRB 050525: MITSuME Optical Observation in VRI
  44. GRB050525A,optical observation
  45. GRB 050525 : Lulin optical afterglow observations
  46. GRB050525: Super-LOTIS observations
  47. GRB050306: optical afterglow not confirmed
  48. GRB 050525: BART optical observation
  49. GRB 050525A: BOOTES simultaneous optical observations
  50. GRB 050525A: Swift-BAT refined analysis
  51. GRB050525: Optical observations
  52. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  53. Konus-Wind observation of GRB 050525
  54. GRB 050525: TAROT observations of the early afterglow
  55. INTEGRAL detection of GRB 050525
  56. GRB 050525, infrared observations
  57. GRB 050525: Optical observation
  58. GRB 050525: observatons of the optical afterglow
  59. GRB050525: ROTSE-III Refined Analysis
  60. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  61. XRF050522: Radio Observations
  62. Swift/UVOT observation of XRF 050522
  63. GRB 050509A: Further I-band imaging
  64. GRB050522,optical observation
  65. GRB050520,optical observation
  66. XRF 050522: Continued NIR P200 Monitoring
  67. Recent GRB BVRcIc field photometry
  68. GRB050520: Radio Observations
  69. XRF 050522: Swift XRT observation
  70. XRF050522, BVRcIc field photometry
  71. XRF050522: Optical Observations
  72. XRF050522: Near-infrared Observations
  73. GRB 050520: VLT/ULTRACAM observations
  74. GRB 050520: Swift XRT refined analysis
  75. XRF 050509c: Swift XRT Upper Limit
  76. XRF050509c: Radio Observations
  77. RBO Observations of GRB050520
  78. GRB 050520: P200 Observations
  79. GRB 050520: TAROT optical limit
  80. GRB 050520: VLT/ULTRACAM observations
  81. GRB 050504: Swift XRT afterglow candidate has faded
  82. GRB 050509B and short GRB-SN association? (corrected)
  83. GRB 050509B and short GRB-SN association?
  84. GRB050502b: Early Observation
  85. GRB050509b, Bok telescope B-band imaging
  86. GRB050509b, SDSS pre-burst observations
  87. GRB 050509b: Keck/Chandra Cross-Correlation
  88. GRB 050509b: Keck/Chandra Cross-Correlation
  89. Chandra observation of GRB 050509b
  90. GRB050509B: Optical observations at the Very Large Telescope
  91. GRB 050509b: No Optical Variability in XRT Error Circle
  92. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  93. GRB 050509c: ROTSE-III Optical Limits
  94. GRB 050505, early TAROT observation
  95. GRB050509c: REM NIR and Optical observations
  96. GRB 050505: SARA Observations
  97. GRB 050509B, Optical Observations
  98. GRB 050509b: Possible Optical Counterpart
  99. GRB 050509A: Optical observations
  100. GRB050509b: Radio 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