Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

42205 results found.

  1. GRB060210: Early Optical Observations
  2. GRB 060210: optical evolution
  3. GRB060210:Faulkes Telescope North Afterglow Confirmation
  4. GRB 060210: candidate afterglow
  5. GRB 060210: Swift detection of a burst
  6. GRB060210: Optical afterglow
  7. GRB 060206: Swift/UVOT Observations
  8. GRB060209: RTT150 optical observations
  9. GRB 060209 : TAROT optical observation
  10. GRB060209A: MASTER optical observation
  11. GRB 060209(?): Swift-BAT detection of a possible burst
  12. GRB 060206: near-infrared observations (JK' imaging)
  13. GRB 060206: WSRT Radio Observations
  14. GRB 060206: TTT Observations
  15. GRB 060206: More PROMPT Detections
  16. GRB 060121 : WIDGET Pre-trigger limit
  17. GRB 060206: Tenagra II Observations
  18. GRB 060206: PROMPT Detections
  19. Retraction of orphan GRB afterglow candidate
  20. GRB060204a: Swift XRT Source is not GRB Afterglow
  21. GRB 060206: optical observations at Asiago
  22. Orphan GRB Afterglow candidate
  23. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  24. GRB 060206: Subaru/FOCAS optical spectroscopy
  25. GRB 060206: IR Detection of the Afterglow
  26. GRB 060206: Lick 3m Spectroscopy
  27. GRB 060204A: ROSAT Pointing
  28. GRB 060206: Super-LOTIS observations
  29. GRB060204A: Swift/UVOT observations
  30. GRB 060206: Swift-BAT refined analysis
  31. GRB 060206 : Lulin optical observations
  32. GRB060206: SDSS Pre-Burst Observations
  33. GRB060206: Swift XRT Refined Analysis
  34. GRB060206: Liverpool Telescope observation
  35. GRB060206: P60 Optical Observations
  36. GRB 060206: KAIT observations
  37. GRB060206: Swift XRT Position
  38. GRB 060206: RAPTOR observations of afterglow candidate variability.
  39. GRB 060206: High redshift burst
  40. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  41. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  42. GRB060206: Optical afterglow
  43. GRB060206: Swift-BAT detection of a burst
  44. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  45. GRB060203: WHT Z-band observations
  46. BAT GRB 060204C is probably not a GRB
  47. GRB060204C: optical observation
  48. GRB 060204B: BVRi-band detections of optical afterglow
  49. GRB 060204A: Swift XRT upper limit
  50. GRB 060204A: FRAM optical observations
  51. GRB060204B: Swift/UVOT refined analysis
  52. GRB 060204C: optical observations
  53. Swift XRT Observation of GRB 060204C
  54. GRB 060204B: Swift-BAT refined analysis
  55. GRB 060204B: ART early limit
  56. GRB060204B: Swift XRT Team Refined Analysis
  57. GRB 060204C: OSN limits
  58. GRB 060204b: Keck/LRIS Afterglow Confirmation
  59. GRB 060204C: BOOTES-IR optical limits
  60. GRB 060204C: Liverpool Telescopes optical limit
  61. GRB 060204C: ROTSE-III Optical Limits
  62. GRB 060204C: Swift-BAT detection of a burst
  63. GRB 060124: Radio Observations
  64. GRB060204B: Faulkes OT candidate
  65. GRB 060204B: ART optical limit
  66. GRB060204B, optical observation
  67. GRB060204B - SDSS pre-burst observations
  68. GRB 060204B: Swift detection of a burst
  69. GRB 060204: a long GRB detected by INTEGRAL
  70. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  71. GRB 060203: RTT150 optical observations
  72. GRB060203: Swift XRT Team Refined Analysis
  73. GRB060203 - Swift UVOT observation
  74. GRB 060203: IR Counterpart
  75. GRB060203: Observations with SARA
  76. GRB 060203: P60 Confirmation of Optical Afterglow
  77. Possible GRB 060203: candidate optical counterpart
  78. Swift BAT Trigger 180151: Swift XRT source detection
  79. Possible GRB 060203: optical observations at Asiago
  80. GRB 060202: PROMPT Observations
  81. Swift-BAT trigger 180151 is unknown origin at this time
  82. GRB 060202: Gemini-N J, H, K_s observations
  83. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  84. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  85. GRB 060202: Refined analysis of the Swift-BAT burst
  86. GRB060202, optical observation
  87. GRB 060202: Swift XRT Team Refined Analysis
  88. GRB060202: Faulkes North observation
  89. GRB 060202: Swift detection of a burst
  90. GRB 060121: Gemini Late-time Observations
  91. Erratum: SDSS pre-burst observations of GRB fields
  92. GRB 060130: PROMPT Observations
  93. GRB 051211A: MDM Observations
  94. GRB 060123: Gemini spectroscopy of the putative host galaxy
  95. GRB 060123: VLA Radio Observations
  96. GRB060130: Optical imaging
  97. GRB060130: REM infrared observations
  98. GRB 060130, SMARTS optical observations
  99. GRB 060130: FRAM optical observations
  100. GRB 060130: a long GRB detected with INTEGRAL

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