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"

914 results found.

  1. GRB 061121: ART detection in Ic
  2. GRB 061109: optical observation
  3. GRB 060927: Early color
  4. GRB 060906: optical observation
  5. GRB 060807: optical limit
  6. GRB060418, BVRcIc field calibration
  7. GRB 060403: MITSuME optical observation
  8. GRB 060323: Tautenburg OT candidate retraction
  9. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  10. Spectral properties of GRB060218/SN2006aj
  11. GRB 060218: emergence of the underlying SN spectrum
  12. GRB 060204B: ART early limit
  13. GRB 060204B: ART optical limit
  14. GRB 060124: ART optical limits during the burst
  15. GRB 060124: Confirmation of the Afterglow
  16. GRB 060124: Optical Observations at Tautenburg
  17. GRB 060115: OT photometry with MITSuME
  18. GRB 060115: MITSuME optical afterglow candidate
  19. GRB 060111B: MITSuME detection of optical afterglow
  20. GRB 060110: Mitsume optical observations
  21. GRB 060110: Optical observation
  22. GRB 060110: Optical limit
  23. GRB 060108: Mitsume optical observations
  24. GRB 060105: Mitsume optical observations
  25. GRB 051227: optical observation
  26. GRB051117B: optical observation
  27. GRB 051109B: GAO 150cm telescope Optical limit
  28. GRB 051111a: Afterglow fading in Ic
  29. GRB 051109: PROMPT Detections
  30. GRB 051109: Rc and Ic observations
  31. GRB 051105b: ART optical limits
  32. GRB 051105: Optical limit
  33. GRB 051021: PROMPT RcIc Observations
  34. GRB 050502b: Optical limit
  35. GRB 051016b: Optical limit
  36. GRB 050922B: optical limit
  37. GRB 050906: RTT150 optical observations
  38. GRB 050908: Optical Observations
  39. GRB 050906: MARGE Optical Limits
  40. GRB 050906: Swift-BAT refined analysis
  41. GRB 050906: Bright galaxy in BAT error box
  42. GRB 050904: SOAR YJ and PROMPT Ic Observations
  43. GRB050824, I-band imaging
  44. GRB050820A: RTT150 optical observations
  45. GRB050820a: PROMPT RcIc Observations
  46. GRB050820A: RTT150 optical observations
  47. GRB 050724: Optical limit
  48. GRB 050717: PROMPT RcIc Observations
  49. GRB 050716: Optical Observations
  50. GRB 050607: PROMPT VRcIc Observations
  51. GRB050505: AAVSO observations
  52. GRB 050412: PROMPT VRcIc Observations
  53. GRB050326: optical limit
  54. GRB 050319: Optical observation
  55. PROMPT VRcIc Observations of GRB 050223
  56. GRB 050117: Optical observation
  57. GRB041219, early time observations
  58. GRB 040924: Afterglow Color
  59. GRB 040916: Afterglow Color at Early Times
  60. GRB041006 (=HETE3570): optical observations
  61. XRF040916: continuing decay of OT
  62. XRF040916, optical observations
  63. XRF040916: Optical Transient Candidate by Subaru
  64. XRF040916, Ic observations
  65. GRB 040825A: Optical observations.
  66. GRB 040730: Optical observations
  67. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  68. SN 2003dh/GRB030329 late-time optical spectroscopy
  69. SN 2003jd (SN/GRB?), Radio Observations
  70. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  71. GRB 031026: Further Ic Observations
  72. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  73. GRB 031026: Ic Observations
  74. XRF 030723: Subaru Optical Observations
  75. GRB 030519B: optical observations.
  76. GRB 030329: Correction to GCN 2254
  77. GRB 030329: Optical Observations
  78. GRB 030416: Optical Observations
  79. GRB 030329 Optical Observations
  80. GRB030429, BVRcIc field photometry
  81. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  82. GRB 030329, the review of the sky area in plate archive (1950-1998)
  83. GRB 030329 and SN 2003dh
  84. GRB 030329, color evolution
  85. OT GRB light curves and SN predictions
  86. GRB030329, new UBVRcIc field photometry
  87. GRB 030324: Optical and NIR Observations
  88. GRB030323: V, R, I photometry
  89. GRB 030226: Ic Observations
  90. GRB 030204: Optical Observations
  91. Type Ic SN2003L (SN/GRB?), optical spectrum
  92. Type Ic SN2003L (SN/GRB?) Radio Observations
  93. GRB021219, optical observations
  94. GRB 021204: I-band Observations
  95. GRB021004, late time optical observations
  96. GRB 021112: Afterglow or Variable Star?
  97. GRB021004, astrometric position
  98. GRB020813, astrometric position
  99. GRB 020715, optical observations
  100. GRB 020714, 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