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"

35954 results found.

  1. GRB 070223: Optical-IR observation with KANATA
  2. GRB 070223, Swift-BAT refined analysis
  3. GRB 070223: Swift-XRT Refined Analysis
  4. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  5. GRB070223 - SDSS Pre-Burst Observations
  6. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  7. GRB 070223: MDM Observations
  8. GRB070223: Swift burst
  9. Konus-Wind and Konus-A observations of GRB 070220
  10. GRB 070220: MITSuME Okayama Optical Observation
  11. GRB 070220: ART-3 Optical and NIR limits
  12. GRB 070220 Swift-BAT Refined Analysis
  13. Swift/UVOT refined analysis of GRB070220
  14. GRB 070209: Swift XRT refined analysis
  15. GRB 070220: Swift-XRT Refined Analysis
  16. GRB 070220: Observation with the KANATA 1.5m telescope
  17. GRB 070219: Gemini Observations
  18. GRB 070220 : Faulkes Telescope North optical limit
  19. GRB 070220: Swift detection of a burst
  20. GRB070219: MASTER-VWF-Kislovodsk observations
  21. GRB 070219: XRT Refined Analysis
  22. GRB 070219: Swift/UVOT Upper limits
  23. GRB 070219: I-band observations
  24. GRB 070219, Swift-BAT refined analysis
  25. GRB 070219: optical TNG observations
  26. GRB 070219: Liverpool Telescope Observations
  27. GRB 070219: ROTSE-III Optical Limits
  28. GRB070219 - SDSS Pre-Burst Observations
  29. GRB 070219: Swift detection of a burst
  30. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  31. GRB 070125 observations with the GMRT
  32. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  33. Swift-BAT trigger 260304 is NOT a burst or transient
  34. GRB 060927: PROMPT Observations
  35. GRB 070201: Correction to GCN 6094
  36. GRB 070129: MDM I-band Detection
  37. GRB 070125: Break in Optical Decay
  38. GRB 070209: Swift XRT analysis
  39. GRB 070201: clarification on localization and Konus-Wind spectra
  40. GRB070208: optical observations
  41. GRB 070201: IPN constraints and nearby galaxies
  42. GRB 070201: Proximity of IPN annulus to M31
  43. GRB 070208: MARGE Optical Observations
  44. IPN localization of very bright long hard GRB 070207
  45. IPN localization of very intense short GRB 070201
  46. GRB 070209, Swift-BAT refined analysis of the short hard burst
  47. GRB 070209: Swift detection of a short hard burst
  48. GRB 070208: Swift XRT refined analysis
  49. GRB 070208: RAPTOR detection of early afterglow onset
  50. GRB070208: Absorption and emission redshift from Gemini
  51. GRB 070208: MDM Optical Decay
  52. GRB 070208, Swift-BAT refined analysis
  53. GRB070208 - SDSS Pre-Burst Observations
  54. GRB 070208: Early IR detection and afterglow astrometry
  55. GRB 070208: Afterglow confirmation from P60
  56. GRB070208: Faulkes Telescope North Afterglow Identification
  57. GRB 070208: ROTSE-III Optical Limits
  58. GRB 070208: MDM Observations
  59. GRB 070208: Swift detection of a burst
  60. GRB 070125 detection with CARMA
  61. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  62. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  63. GRB 070129: afterglow confirmation
  64. GRB070124: Swift-XRT Follow-up Observation
  65. GRB070126: Swift-XRT Observation
  66. GRB 070125: further AAVSO optical observations
  67. GRB 070129: Swift/UVOT Upper limits
  68. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  69. GRB 070125: optical observation
  70. GRB 070125: WSRT Radio Detection
  71. Radio detection of GRB 070125
  72. GRB061217: MAGIC telescope GeV observation
  73. GRB 070125: confirmation of pseudo-redshift
  74. GRB 070129, Swift-BAT refined analysis of a particularly long
  75. GRB 070129: Xinglong TNT optical Upper Limit
  76. GRB 070129: Swift-XRT Refined Analysis
  77. GRB 070129: VLT observations
  78. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  79. GRB 070129: Swift detection of a burst
  80. GRB 070126: Swift/UVOT refined analysis
  81. GRB 070125: further AAVSO optical observations
  82. GRB 070125: MITSuME Okayama optical observation
  83. Konus-Wind observation of GRB 070125
  84. GRB 070125: AAVSO optical observations
  85. GRB 070125: optical observations
  86. GRB 070126: VLT observations
  87. GRB070126: Swift-XRT possible detection of an afterglow
  88. GRB 070125: PROMPT detections
  89. GRB 070124: Suzaku WAM observation of the prompt emissions
  90. GRB 070125: WSRT Radio Observations
  91. GRB 070125: UVOT Detection in Ultraviolet Filters
  92. GRB 070126, Swift-BAT refined analysis of a very faint burst
  93. GRB070125: Optical observation by Kanata
  94. Possible GRB 070126: Swift/UVOT Upper Limit
  95. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  96. GRB 070125: Xinglong TNT optical observations
  97. GRB 070125: Continued P60 Observations
  98. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  99. GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
  100. GRB 070125: Lick 3m Spectroscopy

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