Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

26367 results found.

  1. GRB 050326: Early observations with Swift-UVOT
  2. GRB 050326 XMM-Newton observation
  3. GRB 050326: Swift XRT Position
  4. GRB 050326 BAT refined analysis
  5. GRB050326: delayed XRT observation
  6. GRB050319, color indices
  7. GRB050319: optical observation, March 20-22
  8. GRB050319: RTT150 Optical Observations
  9. Swift-BAT trigger 112060 is not a real GRB
  10. GRB 050318: Swift-BAT refined analysis
  11. GRB050319: VLA Observations
  12. GRB050319: radio observation
  13. GRB 050319: Swift-UVOT detection of the afterglow
  14. GRB 050315: Variability Analysis of Swift BAT Time History
  15. GRB050319: Radio Observations
  16. GRB 050319: NIR afterglow candidate
  17. GRB 050319:Near IR afterglow
  18. GRB 050318: SWIFT-UVOT refined analysis
  19. GRB 050319 : Confirmation of optical afterglow decay
  20. GRB 050319: Swift-BAT refined analysis
  21. GRB050319,optical observation
  22. GRB 050318: Swift/UVOT detection of afterglow emission
  23. RXTE Observations of GRB050318
  24. GRB050223: analysis of the XMM-Newton observation
  25. GRB050316: MASTER before, simultanious and follow up optical
  26. GRB 050306: ROTSE-III early limits
  27. GRB050316: MASTER optical observations
  28. GRB 050315: Swift-BAT further refined analysis
  29. GRB 050315 I-band observations
  30. GRB050315: Radio afterglow
  31. GRB050315: Swift-BAT Refined analysis
  32. Non-detection of GRB050315 in ATCA Radio Observations
  33. GRB 050219b: Gemini/GNIRS near-infrared spectroscopy
  34. GRB 050315: Early Observations with Swift/UVOT
  35. GRB 050306: Radio Observations
  36. GRB050306: 250 GHz upper limit with MAMBO at the IRAM 30m
  37. GRB 050306: optical afterglow
  38. Swift-BAT trigger 107873: No Swift XRT counterpart
  39. GRB 050306: Confirmation of X-ray afterglow
  40. GRB 050306: further TAROT optical data
  41. GRB050309: Early optical limit from P60
  42. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  43. GRB 050309 : Lulin R-band observation
  44. Swift 107873: P60 Optical Observations
  45. GRB 050306: R-band observations
  46. GRB 050306: REM optical-infrared observations
  47. GRB 050306: Possible X-ray Afterglow Position from the Swift
  48. GRB 050306: TAROT optical observations
  49. GRB 050306,optical observation
  50. Ongoing activity of SGR 1806-20 after the giant flare
  51. GRB050215B: Late-Time Swift UVOT Observations
  52. PROMPT VRcIc Observations of GRB 050223
  53. XRF/GRB 050215B: Radio Observations
  54. XMM-Newton Images of GRB 050223
  55. GRB 050219b: candidate NIR afterglow
  56. Confirmed XRF nature for GRB050215b
  57. GRB050223 XMM-Newton observation
  58. INTEGRAL detection of GRB 050223
  59. GRB050223: ROTSE-III Optical Observations
  60. GRB 050223 Swift/BAT detection of a burst
  61. GRB 050223: Swift XRT Position
  62. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  63. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  64. GRB 050219a: Optical observations from LCO
  65. GRB 050219b: Optical and near-IR observations from LCO
  66. GRB 050219b: Swift-BAT detection of a burst
  67. GRB 050219b: CORRECTION: Swift XRT Position
  68. GRB 050219b: Swift XRT Position
  69. GRB 050219: Swift-BAT detection of a burst
  70. GRB 050215b: XRT confirmation of IR afterglow candidate
  71. GRB050215b: P60 Optical Observations
  72. GRB 050215b: Swift XRT Source Variability
  73. GRB 050215B: candidate afterglow
  74. GRB 050215b : Lulin follow-up observation
  75. GRB 050215b, BOOTES-2 simultaneous optical observations
  76. GRB050215A: ROTSE-III Optical Observations
  77. GRB050209: TAROT optical observations
  78. GRB 050209(=U11568): Duration and spectrum
  79. GRB050209: REM optical observations
  80. GRB 050209 I-band observation
  81. GRB 050209 Optical observations
  82. GRB050209: P60 Optical Observations
  83. GRB 050128: Radio observations
  84. Further analysis of the short Swift-BAT GRB 050202
  85. GRB 050202: Short burst detected by Swift-BAT
  86. GRB 050128 Optical observation with REM
  87. SGR1806-20: Swift-BAT detection of a large normal burst
  88. GRB 050128: near-infrared observations with REM
  89. GRB050128,optical observations
  90. GRB050128 Swift-BAT observations
  91. GRB 050128: Swift XRT prompt afterglow position
  92. GRB050126: MASTER optical limit for KECK OT
  93. GRB050126: Burst Parameters Measured by BAT
  94. GRB050126: MASTER optical observations
  95. GRB 050124 I-band observation
  96. GRB050124,optical observation
  97. GRB 050124 : Lulin R-band follow-up observation
  98. GRB050124: Updated Swift XRT Position and Fluxes
  99. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  100. GRB050124: Refined BAT position, spectral and fluence information

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