Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

31727 results found.

  1. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  2. GRB 060313: PROMPT Observations
  3. GRB 060313: Swift/UVOT Observations
  4. GRB060313:Gemini South Observations
  5. GRB 060313: Swift-XRT team refined analysis
  6. GRB060313: optical observations of the afterglow candidate
  7. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  8. GRB 060313, SMARTS optical counterpart?
  9. GRB 060313: Possible optical counterpart
  10. GRB 060313: Swift XRT position
  11. GRB 060313, SMARTS optical/IR observations
  12. GRB060313: optical and near infrared observations with REM
  13. GRB060218: SARA Observations of SN2006aj
  14. GRB 060312: Refined analysis of the Swift-BAT burst
  15. GRB 060312: Swift XRT team refined analysis
  16. GRB060306: APO Ks-band Imaging Observations
  17. GRB 060312: ROTSE-III Optical Limits
  18. GRB 060306: SOAR Ks Observations
  19. GRB 060306: MAGNUM observations
  20. Swift/UVOT observations of GRB060306
  21. GRB 060306: Swift-BAT refined analysis
  22. GRB 060306: Swift-XRT team refined analysis
  23. GRB 060306: PROMPT Observations
  24. GRB 060218: RTT150 optical observations
  25. GRB060218: Ep,i - Eiso correlation
  26. GRB060223b: optical limit
  27. GRB060218/SN 2006aj: optical observation in V
  28. GRB060218/SN 2006aj: optical observation
  29. GRB 060121: HST observations
  30. GRB 060218 : GMRT observation [Correction and Improvement]
  31. GRB 060223b: Swift/UVOT Upper Limits
  32. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  33. GRB 060223B: Swift XRT possible afterglow
  34. GRB 060218/SN 2006aj: ABT observations
  35. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  36. GRB 060218 : Radio upper limits from GMRT
  37. GRB 060218/SN 2006aj: WIRO optical observations
  38. GRB 060218/SN 2006aj: RBO optical observations
  39. GRB 060204B: GETS early limit
  40. GRB 060218: Refined analysis of the radio afterglow
  41. GRB 060223B: ART optical limits
  42. GRB 060223B: Swift-BAT refined analysis
  43. GRB 060223a: Swift/UVOT refined analysis
  44. GRB 060223: Swift XRT Team preliminary analysis
  45. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  46. GRB 060223B: Swift detection of a bright burst
  47. GRB 060223: Swift-BAT refined analysis
  48. Correction to GCN 4816 on GRB060218
  49. GRB 060218/SN 2006aj: optical observations
  50. GRB060218: Optical brightening in V and R
  51. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  52. Spectral properties of GRB060218/SN2006aj
  53. GRB 060219: Swift-BAT refined analysis
  54. GRB 060218: rebrightening
  55. GRB 060218: emergence of the underlying SN spectrum
  56. GRB 060218: Decline in r-band flux
  57. GRB 060218: spectroscopic observations
  58. GRB 060218: Further refined analysis of the Swift-BAT burst
  59. GRB 060218: Likely an underluminous GRB
  60. GRB060218: Optical Spectroscopy of GRB-SN
  61. GRB060218: VLT spectroscopy
  62. GRB 060218: Optical Observations at Xinglong Obs.
  63. GRB 060219: SDSS galaxy inside XRT error circle
  64. GRB060218: UV Detection and Light Curves
  65. GRB060219: SARA Observations
  66. GRB 060219: Swift/UVOT Upper Limits
  67. GRB 060219: Swift-XRT Team refined analysis
  68. GRB 051221B: Swift-XRT Team Refined Analysis
  69. GRB 060219: Partial refined analysis of the Swift-BAT burst
  70. GRB060218: Radio Afterglow Discovery
  71. GRB 060219: Swift-XRT position typo correction
  72. GRB 060219: Swift-XRT position
  73. GRB 060218: optical/nIR observations at La Palma
  74. GRB060219: SDSS pre-burst observations
  75. Oddball GRB 060218, transient or GRB?
  76. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  77. Brightening of the Optical Counterpart of the Possible GRB 060218
  78. GRB 060218: MDM Observations
  79. GRB 060218: Pre-burst detection of a possible host galaxy
  80. GRB 060218A: ROTSE-III Possible Optical Flare
  81. GRB060218: Swift/XRT refined position of a possible burst
  82. Preliminary refined analysis of the Swift-BAT trigger 191157
  83. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  84. GRB 060211B: Swift/UVOT Upper Limits
  85. GRB060218 : SDSS pre-burst observations
  86. GRB 060218: Swift XRT Position
  87. GRB 060213: optical afterglow not confirmed
  88. Swift UVOT observations of GRB060213
  89. GRB 060211B: Skynet Observations
  90. GRB 060213: optical afterglow candidate
  91. GRB060213: Swift XRT observations and possible afterglow candidate
  92. GRB 060206: Confirmation of Rapid Fading at Optical Wavelengths
  93. GRB060213: MASTER final result
  94. GRB 060211b: WIRO NIR Observations
  95. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  96. Konus-Wind observation of bright hard GRB 060213
  97. GRB 060210: Radio Observations
  98. GRB 060211a: WIRO NIR Observations
  99. GRB060211B: REM optical and NIR observations
  100. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec

Advanced

Download all Circulars as a .tar.gz archive:
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