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"

37048 results found.

  1. GRB 070227: optical observations
  2. GRB 070227: Swift/UVOT Upper Limits
  3. GRB 070227: TAROT La Silla observatory optical observations
  4. GRB 070227, Swift-BAT refined analysis
  5. GRB070227: possible X-ray afterglow detection
  6. GRB 070227: Swift detection of a burst in ground analysis
  7. GRB 920925C: optical afterglow candidate
  8. GRB 070224: Optical afterglow confirmation
  9. IBAS Alert n. 4144: not a GRB
  10. GRB 070224: Swift/UVOT Upper Limits
  11. GRB070224: Swift-XRT Astrometrically Corrected Position
  12. VLA observation of GRB 070223
  13. VLA observation of GRB 070220
  14. GRB070224: Magellan Imaging Observations
  15. GRB 070224: WHT K-band imaging
  16. GRB 070224: MDM Observations
  17. GRB070224: Gemini Imaging Observations
  18. GRB 070224: SARA upper limit
  19. GRB070224: Swift-XRT Refined Analysis
  20. GRB 070224: optical afterglow candidate
  21. GRB 070224, Swift-BAT refined analysis
  22. GRB 070224: MASTER-Net refind analysis
  23. GRB 070224: MASTER-VWF-Kislovodsk observations
  24. GRB 070224: MASTER observations
  25. GRB 070224: Swift detection of a burst
  26. GRB 070223: Optical observations
  27. GRB070223: Swift/UVOT refined analysis
  28. GRB 070223: Optical-IR observation with KANATA
  29. GRB 070223, Swift-BAT refined analysis
  30. GRB070223: MASTER-VWF-Kislovodsk observations
  31. GRB 070223: Swift-XRT Refined Analysis
  32. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  33. GRB070223 - SDSS Pre-Burst Observations
  34. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  35. GRB 070223: MDM Observations
  36. GRB070223: Swift burst
  37. Konus-Wind and Konus-A observations of GRB 070220
  38. GRB 070220: MITSuME Okayama Optical Observation
  39. GRB 070220: ART-3 Optical and NIR limits
  40. GRB 070220 Swift-BAT Refined Analysis
  41. Swift/UVOT refined analysis of GRB070220
  42. GRB 070209: Swift XRT refined analysis
  43. GRB 070220: Swift-XRT Refined Analysis
  44. GRB 070220: Observation with the KANATA 1.5m telescope
  45. GRB 070219: Gemini Observations
  46. GRB 070220 : Faulkes Telescope North optical limit
  47. GRB 070220: Swift detection of a burst
  48. GRB070219: MASTER-VWF-Kislovodsk observations
  49. GRB 070219: XRT Refined Analysis
  50. GRB 070219: Swift/UVOT Upper limits
  51. GRB 070219: I-band observations
  52. GRB 070219, Swift-BAT refined analysis
  53. GRB 070219: optical TNG observations
  54. GRB 070219: Liverpool Telescope Observations
  55. GRB 070219: ROTSE-III Optical Limits
  56. GRB070219 - SDSS Pre-Burst Observations
  57. GRB 070219: Swift detection of a burst
  58. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  59. GRB 070125 observations with the GMRT
  60. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  61. Swift-BAT trigger 260304 is NOT a burst or transient
  62. GRB 060927: PROMPT Observations
  63. GRB 070201: Correction to GCN 6094
  64. GRB 070129: MDM I-band Detection
  65. GRB 070125: Break in Optical Decay
  66. GRB 070209: Swift XRT analysis
  67. GRB 070201: clarification on localization and Konus-Wind spectra
  68. GRB070208: optical observations
  69. GRB 070201: IPN constraints and nearby galaxies
  70. GRB 070201: Proximity of IPN annulus to M31
  71. GRB 070208: MARGE Optical Observations
  72. IPN localization of very bright long hard GRB 070207
  73. IPN localization of very intense short GRB 070201
  74. GRB 070209, Swift-BAT refined analysis of the short hard burst
  75. GRB 070209: Swift detection of a short hard burst
  76. GRB 070208: Swift XRT refined analysis
  77. GRB 070208: RAPTOR detection of early afterglow onset
  78. GRB070208: Absorption and emission redshift from Gemini
  79. GRB 070208: MDM Optical Decay
  80. GRB 070208, Swift-BAT refined analysis
  81. GRB070208 - SDSS Pre-Burst Observations
  82. GRB 070208: Early IR detection and afterglow astrometry
  83. GRB 070208: Afterglow confirmation from P60
  84. GRB070208: Faulkes Telescope North Afterglow Identification
  85. GRB 070208: ROTSE-III Optical Limits
  86. GRB 070208: MDM Observations
  87. GRB 070208: Swift detection of a burst
  88. GRB 070125 detection with CARMA
  89. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  90. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  91. GRB 070129: afterglow confirmation
  92. GRB070124: Swift-XRT Follow-up Observation
  93. GRB070126: Swift-XRT Observation
  94. GRB 070125: further AAVSO optical observations
  95. GRB 070129: Swift/UVOT Upper limits
  96. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  97. GRB 070125: optical observation
  98. GRB 070125: WSRT Radio Detection
  99. Radio detection of GRB 070125
  100. GRB061217: MAGIC telescope GeV observation

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