Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
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"

25822 results found.

  1. GRB 080903: Enhanced Swift-XRT position
  2. GRB 080903, Swift-BAT refined analysis
  3. GRB 080903: optical observations
  4. GRB 080903: Liverpool Telescope observations
  5. GRB 080903: Optical afterglow candidate
  6. GRB 080903: TAROT Calern observatory optical observations
  7. GRB 080903: Swift detection of a burst
  8. GRB 080830: Fermi Gamma-ray Burst Monitor detection
  9. SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
  10. SGR 0501+4516: preliminary results of the first XMM-Newton observation
  11. nIR observations of SGR 0501+4516
  12. SGR 0501+4516: Confirmation of the NIR counterpart
  13. GRB080828: Swift/UVOT Upper Limits
  14. SGR 0501+4516: Detection of possible optical counterpart
  15. GRB080825B: Swift/UVOT Upper Limits
  16. GRB 080828: Swift-XRT detection of a possible X-ray afterglow
  17. VLA non-detection of SGR 0501+4516
  18. Swift trigger 322590: BAT detection of a possible burst
  19. GRB 080828: SuperAGILE GRB Localization
  20. Enhanced Swift-XRT position of SGR 0501+4516
  21. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  22. GRB080823: Fermi Gamma-ray Burst Monitor detection
  23. GRB 080824: Fermi Gamma Ray Burst Monitor detection
  24. Konus-Wind observation of GRB 080825B
  25. GRB080825C: GLAST Burst Monitor detection
  26. GRB 080825B: Swift-XRT team analysis
  27. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  28. Suzaku ToO Observation of SGR 0501+4516
  29. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  30. GRB 080825B: GRB Localization by SuperAGILE
  31. Radio Detection of SGR 0501+4516
  32. GRB 080822B, Swift-BAT refined analysis
  33. SGR 0501+4516: Astrotel-Caucasus optical observations
  34. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  35. New Soft Gamma Repeater 0501+4516 (GRB 080822): GLAST Burst Monitor detection
  36. SGR 0501+4516: optical observations
  37. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  38. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  39. GRB080818B: GLAST Burst Monitor detection
  40. GRB 080822: Swift detection of a short burst
  41. GLAST Burst Monitor detection of a GRB: 080816B
  42. GLAST Burst Monitor detection of GRB 080818
  43. GLAST Burst Monitor detection of GRB080817B
  44. GLAST Burst Monitor detection of GRB 080817
  45. GLAST Burst Monitor detection of GRB080816
  46. GRB080810 - optical observations
  47. GLAST Burst Monitor detection of GRB 080812
  48. Radio detection of GRB 080810 with the VLA
  49. GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
  50. GLAST Burst Monitor detection of GRB 080810
  51. First GLAST Burst Monitor GRB Circulars
  52. GRB 080810: Swift/UVOT Refined Analysis
  53. GRB 080810: Liverpool Telescope observations
  54. GRB 080810: Kanazawa optical observation
  55. GRB 080810: OSN follow-up
  56. GRB 080810: Swift-XRT Team refined analysis
  57. GRB 080810: Enhanced Swift-XRT position
  58. GRB 080810: KANATA optical-NIR observation, update
  59. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  60. GRB 080810, Swift-BAT refined analysis
  61. GRB 080810 : optical observation with KANATA
  62. GRB 080810: Swift detection of a burst with a bright optical afterglow
  63. GRB 080723B: GROND upper limits
  64. GRB 080723B: XMM-Newton observation
  65. GRB 080805: Faulkes Telescope South optical observations
  66. GRB 080804: GROND observations
  67. GRB 080727B: Late VLT imaging
  68. GRB 080805: Swift-XRT Refined Analysis
  69. GRB 080805: Swift/UVOT Upper Limits
  70. GRB 080804: Swift-XRT Refined Analysis
  71. GRB 080804: Swift/UVOT Refined Analysis
  72. GRB 080805, Swift-BAT refined analysis
  73. GRB 080804, Swift-BAT refined analysis
  74. GRB 080804: Enhanced Swift-XRT position
  75. GRB 080804: Faulkes Telescope South observations
  76. GRB080805 optical limit by "Pi of the Sky"
  77. GRB 080805: Afterglow confirmation
  78. GRB 080805: GROND detection of possible afterglow
  79. GRB 080805: Swift detection of a burst
  80. GRB 080804: Swift detection of a burst with optical afterglow
  81. GRB 080804: ROTSE-III Detection of Optical Counterpart
  82. GRB 080802: Swift/UVOT Upper Limits
  83. GRB 080802: UVI Telescope Upper Limit
  84. GRB 080802, Swift-BAT refined analysis
  85. GRB 080802: Swift detection of a probable burst
  86. GRB 080727C: Suzaku WAM observation of the prompt emission
  87. GRB 080727B: IR photometry
  88. GRB 080727C: TAROT Calern observatory optical observations
  89. GRB 080727B: KAIT photometry and an early lightcurve break
  90. GRB 080727C, Swift-BAT refined analysis
  91. GRB 080727C: Swift/UVOT Upper Limits
  92. GRB 080727C: Swift XRT refined analysis
  93. GRB 080727C: Liverpool Telescope observations
  94. GRB 080727A: VLT upper limits
  95. GRB 080727C: Enhanced Swift-XRT position
  96. GRB080727C: RTT150 optical observations
  97. GRB 080727C: Swift detection of a burst
  98. Swift detection of XTE J1701-407
  99. GRB 080727B: Swift/UVOT Upper Limits
  100. BAT Trigger 318150 is not a GRB

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