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"

45649 results found.

  1. GRB 070227: TAROT La Silla observatory optical observations
  2. GRB 070227, Swift-BAT refined analysis
  3. GRB070227: possible X-ray afterglow detection
  4. GRB 070227: Swift detection of a burst in ground analysis
  5. GRB 920925C: optical afterglow candidate
  6. GRB 070224: Optical afterglow confirmation
  7. IBAS Alert n. 4144: not a GRB
  8. GRB 070224: Swift/UVOT Upper Limits
  9. GRB070224: Swift-XRT Astrometrically Corrected Position
  10. VLA observation of GRB 070223
  11. VLA observation of GRB 070220
  12. GRB070224: Magellan Imaging Observations
  13. GRB 070224: WHT K-band imaging
  14. GRB 070224: MDM Observations
  15. GRB070224: Gemini Imaging Observations
  16. GRB 070224: SARA upper limit
  17. GRB070224: Swift-XRT Refined Analysis
  18. GRB 070224: optical afterglow candidate
  19. GRB 070224, Swift-BAT refined analysis
  20. GRB 070224: MASTER-Net refind analysis
  21. GRB 070224: MASTER-VWF-Kislovodsk observations
  22. GRB 070224: MASTER observations
  23. GRB 070224: Swift detection of a burst
  24. GRB 070223: Optical observations
  25. RHESSI Spectrum of GRB070220
  26. GRB070223: Swift/UVOT refined analysis
  27. GRB 070223: Optical-IR observation with KANATA
  28. GRB 070223, Swift-BAT refined analysis
  29. GRB070223: MASTER-VWF-Kislovodsk observations
  30. GRB 070223: Swift-XRT Refined Analysis
  31. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  32. GRB070223 - SDSS Pre-Burst Observations
  33. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  34. GRB 070223: MDM Observations
  35. GRB070223: Swift burst
  36. Konus-Wind and Konus-A observations of GRB 070220
  37. GRB 070220: MITSuME Okayama Optical Observation
  38. GRB 070220: ART-3 Optical and NIR limits
  39. GRB 070220 Swift-BAT Refined Analysis
  40. Swift/UVOT refined analysis of GRB070220
  41. GRB 070209: Swift XRT refined analysis
  42. GRB 070220: Swift-XRT Refined Analysis
  43. GRB 070220: Observation with the KANATA 1.5m telescope
  44. GRB 070219: Gemini Observations
  45. GRB 070220 : Faulkes Telescope North optical limit
  46. GRB 070220: Swift detection of a burst
  47. GRB070219: MASTER-VWF-Kislovodsk observations
  48. GRB 070219: XRT Refined Analysis
  49. GRB 070219: Swift/UVOT Upper limits
  50. GRB 070219: I-band observations
  51. GRB 070219, Swift-BAT refined analysis
  52. GRB 070219: optical TNG observations
  53. GRB 070219: Liverpool Telescope Observations
  54. GRB 070219: ROTSE-III Optical Limits
  55. GRB070219 - SDSS Pre-Burst Observations
  56. GRB 070219: Swift detection of a burst
  57. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  58. GRB 070125 observations with the GMRT
  59. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  60. Swift-BAT trigger 260304 is NOT a burst or transient
  61. GRB 060927: PROMPT Observations
  62. GRB 070201: Correction to GCN 6094
  63. GRB 070129: MDM I-band Detection
  64. GRB 070125: Break in Optical Decay
  65. GRB 070209: Swift XRT analysis
  66. GRB 070201: clarification on localization and Konus-Wind spectra
  67. GRB070208: optical observations
  68. GRB 070201: IPN constraints and nearby galaxies
  69. GRB 070201: Proximity of IPN annulus to M31
  70. GRB 070208: MARGE Optical Observations
  71. IPN localization of very bright long hard GRB 070207
  72. IPN localization of very intense short GRB 070201
  73. GRB 070209, Swift-BAT refined analysis of the short hard burst
  74. GRB 070209: Swift detection of a short hard burst
  75. GRB 070208: Swift XRT refined analysis
  76. GRB 070208: RAPTOR detection of early afterglow onset
  77. GRB070208: Absorption and emission redshift from Gemini
  78. GRB 070208: MDM Optical Decay
  79. GRB 070208, Swift-BAT refined analysis
  80. GRB070208 - SDSS Pre-Burst Observations
  81. GRB 070208: Early IR detection and afterglow astrometry
  82. GRB 070208: Afterglow confirmation from P60
  83. GRB070208: Faulkes Telescope North Afterglow Identification
  84. GRB 070208: ROTSE-III Optical Limits
  85. GRB 070208: MDM Observations
  86. GRB 070208: Swift detection of a burst
  87. GRB 070125 detection with CARMA
  88. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  89. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  90. GRB 070129: afterglow confirmation
  91. GRB070124: Swift-XRT Follow-up Observation
  92. GRB070126: Swift-XRT Observation
  93. GRB 070125: further AAVSO optical observations
  94. GRB 070129: Swift/UVOT Upper limits
  95. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  96. GRB 070125: optical observation
  97. GRB 070125: WSRT Radio Detection
  98. GRB070129: MITSuME optical observation
  99. Radio detection of GRB 070125
  100. GRB061217: MAGIC telescope GeV observation

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