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"

20498 results found.

  1. GRB 050509B and short GRB-SN association? (corrected)
  2. GRB 050509B and short GRB-SN association?
  3. GRB050502b: Early Observation
  4. GRB050509b, Bok telescope B-band imaging
  5. GRB050509b, SDSS pre-burst observations
  6. GRB 050509b: Keck/Chandra Cross-Correlation
  7. GRB 050509b: Keck/Chandra Cross-Correlation
  8. Chandra observation of GRB 050509b
  9. GRB 050509b: RAPTOR deep, early limits.
  10. GRB050509B: Optical observations at the Very Large Telescope
  11. GRB 050509b: No Optical Variability in XRT Error Circle
  12. GRB 050509c: ROTSE-III Optical Limits
  13. GRB 050505, early TAROT observation
  14. GRB050509c: REM NIR and Optical observations
  15. GRB 050505: SARA Observations
  16. Swift UVOT Follow-up Observations of GRB 050509B
  17. GRB 050509A: Optical observations
  18. GRB050509b: Radio Observations
  19. GRB 050509B: ROTSE-III Optical Limits
  20. Swift Detection of GRB050509b: A short duration burst
  21. Swift Detection of the Burst GRB050509
  22. GRB 050505: Keck I-band Magnitude
  23. GRB 050505, simultaneous optical observation
  24. GRB 050505: Further Swift UVOT observations.
  25. GRB050505: AAVSO observations
  26. GRB050416A : 1 GHz limit from GMRT
  27. GRB 050505 UVOT
  28. GRB050505: Optical Afterglow Candidate
  29. GRB 050416b:Swift XRT afterglow upper limits
  30. GRB 050416b:Swift XRT afterglow upper limits
  31. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  32. GRB050502b: Afterglow Confirmation
  33. GRB050502: P200 Observations (Correction)
  34. GRB050502: P200 Observations
  35. Swift UVOT observation of GRB 050504
  36. GRB050504: P60 Observations
  37. GRB (?) 050504: IR Observations, Intriguing Source
  38. GRB 050502b, Optical observations
  39. GRB050502a: P60 Observations (Correction)
  40. GRB050502a: P60 Observations
  41. Renewal of SGR 1806-20 activity
  42. GRB050502A: Optical Observations
  43. GRB050502B Swift-BAT refined analysis
  44. GRB 050502b: Swift XRT Position
  45. Swift Detection of the Bright Burst GRB050502b
  46. GRB050502: ANU 1m optical Observations
  47. GRB 050502: ROTSE-III Detection of Possible Counterpart
  48. Swift/BAT possible detection of a weak burst GRB050430
  49. GRB050416a: Radio Detection
  50. GRB 050422: Swift-UVOT observation
  51. GRB 050422: Swift XRT Position
  52. Swift Detection of GRB 050422
  53. GRB 050421: SLOTIS observations
  54. GRB 050421: Further Analysis of IR imaging
  55. GRB050421: Radio Observations
  56. GRB050421: Radio Observations
  57. GRB 050421: IR Observations
  58. GRB 050421: ROTSE-III Optical Limits
  59. GRB050421
  60. GRB 050421: early Swift XRT analysis results
  61. GRB 050421: NIR observations
  62. GRB050421: P60 Observations
  63. GRB 050421: BOOTES-2 simultaneous optical observations
  64. Swift Detection of GRB050421
  65. GRB 050416b: Tentative Swift XRT Position
  66. GRB 050315: potential host galaxy
  67. GRB050326: analysis of the XMM-Newton observation
  68. GRB050418: Null Optical Observations
  69. GRB 050412: Chandra observations
  70. GRB050416A, optical observations
  71. GRB 050418: Swift-BAT refined analysis
  72. GRB 050416: Mitsume optical observation
  73. GRB 050416b: LCO observations
  74. GRB 050416b: LCO observations
  75. GRB050416B: IR observations
  76. GRB 050416: Swift/UVOT refined analysis
  77. Swift-BAT detection of GRB 050416b
  78. GRB050412: Radio Observations
  79. GRB 050416: Swift/UVOT detection of afterglow emission
  80. GRB050416: Refined Swift-XRT analysis
  81. GRB 050416,optical observation
  82. GRB050416: P200 NIR Observations
  83. GRB 050416: Swift XRT Position
  84. GRB 050416: Radio observations
  85. Swift BAT/XRT Detection of GRB 050416
  86. GRB 050412: Subaru observations
  87. GRB 050408: RTT150 optical observations
  88. GRB 050412: PROMPT VRcIc Observations
  89. GRB 050408: Kuiper 1.5m observations
  90. GRB 050412: optical observations
  91. GRB 050412: early Swift XRT analysis results
  92. GRB 050412: Swift-BAT refined analysis
  93. GRB 050412: Early Optical/Ultraviolet Observations with
  94. GRB 050408: SDSS Field Calibration
  95. GRB050412: P60 Observations
  96. GRB 050412: Swift XRT Position
  97. GRB050412: ROTSE-III Optical Limits
  98. GRB 050412: IR and Optical observations
  99. GRB 050412: IR Observations
  100. GRB050408: 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