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"

36048 results found.

  1. GRB 060204B: BVRi-band detections of optical afterglow
  2. GRB 060204A: Swift XRT upper limit
  3. GRB 060204A: FRAM optical observations
  4. GRB060204B: Swift/UVOT refined analysis
  5. GRB 060204C: optical observations
  6. Swift XRT Observation of GRB 060204C
  7. GRB 060204B: Swift-BAT refined analysis
  8. GRB 060204B: ART early limit
  9. GRB060204B: Swift XRT Team Refined Analysis
  10. GRB 060204C: OSN limits
  11. GRB 060204b: Keck/LRIS Afterglow Confirmation
  12. GRB 060204C: BOOTES-IR optical limits
  13. GRB 060204C: Liverpool Telescopes optical limit
  14. GRB 060204C: ROTSE-III Optical Limits
  15. GRB 060204C: Swift-BAT detection of a burst
  16. GRB 060124: Radio Observations
  17. GRB060204B: Faulkes OT candidate
  18. GRB 060204B: ART optical limit
  19. GRB 060204A: further INTEGRAL results
  20. GRB060204B - SDSS pre-burst observations
  21. GRB 060203: Swift-BAT refined analysis
  22. GRB 060204B: Swift detection of a burst
  23. GRB 060204: a long GRB detected by INTEGRAL
  24. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  25. GRB 060203: RTT150 optical observations
  26. GRB060203: Swift XRT Team Refined Analysis
  27. Swift-BAT trigger is GRB 060203
  28. GRB 060203: IR Counterpart
  29. GRB060203: Observations with SARA
  30. GRB 060203: P60 Confirmation of Optical Afterglow
  31. Possible GRB 060203: candidate optical counterpart
  32. Possible GRB 060203: optical observations at Asiago
  33. GRB 060202: PROMPT Observations
  34. GRB 060202: GETS observation
  35. GRB 060202: Gemini-N J, H, K_s observations
  36. GRB 060202 : Kiso B and R band limit
  37. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  38. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  39. GRB 060202: Refined analysis of the Swift-BAT burst
  40. GRB 060202: Swift/UVOT upper limits
  41. GRB 060202: Swift XRT Team Refined Analysis
  42. GRB 060202 : Lulin R and I band limit
  43. GRB060202: Faulkes North observation
  44. GRB 060202: Swift detection of a burst
  45. GRB 060121: Gemini Late-time Observations
  46. Erratum: SDSS pre-burst observations of GRB fields
  47. GRB 060130: PROMPT Observations
  48. GRB 060130: Swift/XRT observation
  49. GRB 051211A: MDM Observations
  50. GRB 060123: Gemini spectroscopy of the putative host galaxy
  51. GRB 060123: VLA Radio Observations
  52. GRB060130: Optical imaging
  53. GRB060130: REM infrared observations
  54. GRB 060130, SMARTS optical observations
  55. GRB 060130: FRAM optical observations
  56. GRB 060130: further INTEGRAL IBIS results
  57. GRB 060130: a long GRB detected with INTEGRAL
  58. Possible GRB 051221B: MDM Correction
  59. GRB050121: optical observation
  60. GRB050121b: optical observation
  61. GRB 060121: Confirmation of NIR Afterglow
  62. GRB060124: optical observation
  63. GRB060124: optical observations
  64. GRB 060123: Swift refined analysis of an unusual GRB
  65. GRB060124, BVRcIc field calibration
  66. GRB060105: refined analysis of the Suzaku observation
  67. GRB060124 optical observations
  68. GRB 060121: Probable Detection of NIR Afterglow
  69. GRB060124: optical observation
  70. GRB 060116 HST observations
  71. GRB 060124: HETE detection and spectrum of the main peak
  72. Refined XRT Position for GRB 060123
  73. Konus-Wind observation of GRB 060124
  74. GRB060124: detailed XRT analysis
  75. GRB 060124 Optical Observations
  76. GRB 060124: ART optical limits during the burst
  77. GRB060123: Optical and IR Imaging
  78. GRB 060123: P200 Observations
  79. GRB 060124: Keck optical spectrum
  80. GRB 060124: Keck Absorption Redshift
  81. GRB 060124: MDM Optical Spectrum
  82. GRB 060124: XRT refined analysis
  83. GRB 060124: R band Observations
  84. GRB 060124 : Optical observation at Xinglong and Kiso
  85. GRB060124: optical observations at Asiago
  86. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  87. GRB060123: SDSS pre-burst observations
  88. GRB 060123: Swift detection of a very long, faint burst
  89. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  90. GRB 060121: OHP optical limits
  91. GRB 060124: TAROT optical limits
  92. GRB 060124: Swift/UVOT Observation
  93. GRB 060124: Confirmation of the Afterglow
  94. GRB 060124: XRT position
  95. GRB 060124: Optical Afterglow Candidate from Tautenburg
  96. GRB 050124 : Kiso Optical limit
  97. GRB 060124: Optical Observations at Tautenburg
  98. GRB 060117: Suzaku WAM observation of the prompt emission
  99. GRB060124:MASTER optical observation
  100. GRB 060111B: Suzaku WAM observation of the prompt emission

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