Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

45890 results found.

  1. Swift UVOT Follow-up Observations of GRB 050509B
  2. GRB 050509B, Optical Observations
  3. GRB 050509B: Swift/XRT refined analysis
  4. GRB050509a: Swift UVOT observations
  5. GRB 050509b: Optical observations
  6. GRB 050509b: Precision Astrometry
  7. GRB 050509b: Possible Optical Counterpart
  8. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  9. GRB 050509A: Optical observations
  10. GRB 050509b: Optical Counterpart Candidate
  11. GRB050509b: Radio Observations
  12. GRB 050509b: PAIRITEL and WIYN Observations
  13. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  14. GRB 050509b: optical observations
  15. GRB 050509b: Swift XRT Position
  16. GRB 050509B: ROTSE-III Optical Limits
  17. Swift Detection of GRB050509b: A short duration burst
  18. GRB 050509a: Swift XRT Position
  19. Swift Detection of the Burst GRB050509
  20. Swift-BAT detection of GRB 050507
  21. GRB 050505: Keck I-band Magnitude
  22. GRB 050505: early time observations
  23. GRB 050505 - Faulkes Telescope North observations
  24. GRB 050502a: Swift XRT Upper Limit
  25. GRB 050505, simultaneous optical observation
  26. GRB050505: Infrared observations
  27. GRB 050505: Further Swift UVOT observations.
  28. GRB050505: AAVSO observations
  29. GRB050416A : 1 GHz limit from GMRT
  30. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  31. GRB 050505 UVOT
  32. GRB050505: Optical Afterglow Candidate
  33. GRB 050505: Swift XRT Position
  34. GRB050505 Swift-BAT refined analysis
  35. GRB 050502a: Optical Observations
  36. GRB 050416b:Swift XRT afterglow upper limits
  37. GRB 050416b:Swift XRT afterglow upper limits
  38. Swift-BAT detection of GRB050505
  39. GRB 050504: Swift XRT position
  40. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  41. GRB050502b: Afterglow Confirmation
  42. GRB050502: P200 Observations (Correction)
  43. GRB050502: P200 Observations
  44. GRB 050504 : R band observation at Lulin observatory
  45. Swift UVOT observation of GRB 050504
  46. GRB 050504, R band Observations
  47. GRB050504: Faulkes North optical robotic limit
  48. GRB 050502b, V band Observations
  49. GRB050504: P60 Observations
  50. GRB 050504: A long GRB detected with INTEGRAL
  51. GRB (?) 050504: IR Observations, Intriguing Source
  52. GRB 050502b, Optical observations
  53. GRB050502a: P60 Observations (Correction)
  54. GRB050502a: P60 Observations
  55. Renewal of SGR 1806-20 activity
  56. GRB 050502a: RBO Observations
  57. GRB 050502A: WSRT Radio Observations
  58. GRB050502A: Optical Observations
  59. GRB050502B Swift-BAT refined analysis
  60. GRB050502B: I band source in XRT error circle
  61. Swift UVOT refined analysis
  62. Retraction of Swift-BAT trigger 116145
  63. GRB 050502a : R band observation at Lulin observatory
  64. GRB 050502b : optical observation at Lulin observatory
  65. GRB 050502b: Swift XRT Position
  66. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  67. GRB050502B: Optical Limits from ANU 1m
  68. Swift Detection of the Bright Burst GRB050502b
  69. GRB 050502: INTEGRAL results
  70. GRB050502: ANU 1m optical Observations
  71. GRB 050502: Confirmed variability of the afterglow candidate +
  72. GRB 050502: PAIRITEL IR Observations
  73. GRB050502 - Correction on the Optical Candidate from the Liverpool
  74. GRB050502 - Optical Candidate from the Liverpool Telescope
  75. GRB 050502 - A long GRB detected with INTEGRAL
  76. GRB 050502: ROTSE-III Detection of Possible Counterpart
  77. Swift-BAT Trigger 115881 is not a real GRB
  78. Swift/BAT possible detection of a weak burst GRB050430
  79. GRB 050401: Rc observation
  80. GRB050416a: Radio Detection
  81. GRB 050422: Swift-UVOT observation
  82. GRB 050422: Swift-BAT refined analysis
  83. GRB 050422: Swift XRT Position
  84. Swift Detection of GRB 050422
  85. GRB 050421: NIR observations
  86. GRB 050416: Optical/NIR observations
  87. GRB 050421: SLOTIS observations
  88. GRB 050421: Further Analysis of IR imaging
  89. GRB050421: Radio Observations
  90. GRB050421: Radio Observations
  91. GRB 050421: Swift-UVOT observation
  92. GRB 050421: IR Observations
  93. GRB 050421: Swift-BAT refined analysis
  94. GRB 050421: ROTSE-III Optical Limits
  95. GRB 050421: NIR observations re-examination
  96. GRB050421
  97. GRB 050421: early Swift XRT analysis results
  98. GRB 050421: NIR observations
  99. GRB050421: P60 Observations
  100. GRB 050421: BOOTES-2 simultaneous optical observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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