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"

20966 results found.

  1. GRB 060510B: MDM Observations and candidate OT
  2. GRB 060510B: Swift detection of a burst
  3. GRB 060505: PROMPT Observations
  4. GRB 060507: MDM Optical Upper Limit
  5. GRB060507: Swift XRT position
  6. GRB060505: Swift/UVOT Observations
  7. GRB060425: new MASTER survey method
  8. GRB 060306: Further Analysis of SOAR and APO NIR Observations
  9. GRB 060505: Swift XRT afterglow canditate position
  10. GRB 060502b: Second epoch Gemini observations
  11. GRB 060502B: optical observations
  12. GRB 060502B: AROMA refined photometric calibration
  13. GRB 060502B MDM Follow-up Observation
  14. GRB 060502A: Swift/UVOT source detection
  15. GRB 060502B: MDM Optical Observation
  16. GRB 060502B: AROMA optical observations
  17. Short GRB 060502B: Tautenburg Observation
  18. GRB 060427B Milagro GeV/TeV Observations
  19. GRB 060502A: TTT Observations
  20. GRB 060501: P60 Observations and Candidate Retraction
  21. GRB 060502B: MASTER optical observations
  22. GRB060502: Gemini spectroscopy
  23. GRB 060502: APO Spectroscopic Observations
  24. GRB060501: Swift UVOT followup observations
  25. GRB060502: Super-LOTIS Observations
  26. GRB 060502: P60 Afterglow Confirmation
  27. GRB 060501: MDM Observations
  28. GRB060501: Super-LOTIS observations
  29. GRB060428B - SDSS Pre-Burst Observations
  30. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  31. GRB 060428B: MDM Observations
  32. GRB 060428A: PROMPT Observations
  33. GRB 060427B: MASTER optical observations
  34. GRB 060428B: KAIT observations
  35. GRB060425:MASTER optical limit
  36. GRB 051117A: Bright host galaxy not confirmed
  37. GRB060428A: Swift/UVOT observations.
  38. GRB 060428b : Kiso R-band limit
  39. GRB 060428b: Optical afterglow candidate
  40. GRB 060427: NIR observations
  41. GRB060427: Xinglong optical Observations
  42. GRB 060427: NOT observations
  43. GRB060425:MASTER survey observations
  44. GRB060424: optical afterglow detection
  45. GRB060418: Further Analysis of MIKE Spectroscopy
  46. GRB 060424: Swift detection of a burst
  47. GRB 060421: TTT Observations
  48. OT 060420: Likely Not a New Cosmic Transient
  49. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  50. GRB060421: Swift/UVOT observations
  51. GRB 060418: prediction of t_break
  52. GRB060418: optical observations
  53. Konus-Wind observation of GRB 060418
  54. Erratum of GCN 4983 for GRB 060418 IR follow-up
  55. GRB 060418 : IR afterglow observations
  56. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  57. GRB 060418: Radio Observations
  58. GRB060418: Swift/UVOT Observations
  59. GRB060418: Optical Observations
  60. VLT/UVES observations of GRB060418
  61. GRB 060418, SMARTS continuing afterglow observations
  62. GRB 060418: PROMPT Detections
  63. GRB 060418, SMARTS optical/IR afterglow observations
  64. GRB060418: Magellan/MIKE Spectroscopic Redshift
  65. GRB 060418: REM candidate afterglow
  66. GRB 060413: REM NIR Observations
  67. GRB 060413: Watcher UBVR observations
  68. GRB060403: optical observations
  69. GRB 060403 Optical observations
  70. SGR 1900+14: BAT observations
  71. HETE trigger H4044: RTT150 optical observations
  72. GRB060331: Swift/UVOT upper limits
  73. Swift XRT observations of the HETE transient H4043
  74. H4043, an unusual high-energy transient observed by HETE
  75. GRB 060322: LNA optical limit
  76. INTEGRAL and XMM ToO observations of SGR1900+14
  77. SGR 1900+14: Swift-BAT detection of a bright outburst
  78. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  79. GRB 060323 : WIDGET simultaneous optical observations
  80. GRB 060323: Early optical observation at Xinglong
  81. GRB060218, optical observations
  82. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  83. GRB060323: NOT optical observations
  84. GRB 060322: IAC80 optical observations
  85. GRB 060322: Swift XRT afterglow candidate
  86. GRB060323: P60 Observations
  87. GRB 060323: Swift/UVOT Observations
  88. GRB 060323: optical afterglow confirmed
  89. GRB060323: NOT observations
  90. GRB 060323: Optical Observations
  91. GRB 060323: Tautenburg OT candidate retraction
  92. GRB 060323: optical observations at TNG
  93. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  94. GRB060323 - SDSS Pre-Burst Observations
  95. GRB060218/SN2006aj: optical observations
  96. GRB 060319: IAC-80 optical observations
  97. GRB 060319 optical observations at TNG
  98. GRB060319 - SDSS Pre-burst Observations
  99. GRB060313: Radio Observations
  100. GRB 060313: early afterglow NIR upper limits with REM

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