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"

34118 results found.

  1. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  2. GRB 220403B: Fermi GBM detection
  3. GRB 220404A: Swift detection of a burst
  4. GRB 220403B: Swift-XRT refined Analysis
  5. GRB 220403B: LBT observations
  6. Swift GRB 220403B: Global MASTER-Net observations report
  7. GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
  8. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  9. GRB 220403A: Tautenburg observations
  10. GRB 220403B: optical detection by D50
  11. GRB 220403B: Swift detection of a burst with an optical counterpart
  12. Fermi GRB 220403A: Global MASTER-Net observations report
  13. GRB 220403A: Fermi GBM Final Real-time Localization
  14. GRB 220401A: Swift/BAT-GUANO detection outside the coded FOV
  15. GRB 220401A: Fermi GBM observation
  16. Swift Trigger 1100848 is likely not a GRB
  17. Fermi GRB 220401B: Global MASTER-Net observations report
  18. GRB 220401B: Fermi GBM Final Real-time Localization
  19. GRB 220401A: Fermi GBM Final Localization
  20. Fermi Gamma-ray Burst Monitor trigger 220331776/670444627 is not a GRB
  21. GRB 220331A: Fermi GBM Final Real-time Localization
  22. Fermi GRB 220330A: Global MASTER-Net observations report
  23. GRB 220330A: Fermi GBM Final Real-time Localization
  24. GRB 220325A: GRANDMA observations
  25. GRB 220320A: Detection by VZLUSAT-2
  26. Konus-Wind observation of GRB 220320A
  27. GRB 220325A: Swift/UVOT Upper Limits
  28. GRB 211024B: Host galaxy redshift from X-shooter/VLT
  29. GRB 220325A: Swift-BAT refined analysis
  30. ZTF22aaajecp/AT2022cmc: continued optical observations (Mondy, TSHAO, AbAO)
  31. GRB 220325A: Tautenburg observations
  32. GRB 220326A: Fermi GBM Final Localization
  33. GRB 220325A: LCO Optical Upper Limits
  34. GRB 220325A: Swift-XRT refined Analysis
  35. GRB 220325A: 1.3m DFOT Optical upper limit
  36. GRB 220325B: Fermi GBM Final Localization
  37. Fermi GBM Sub-Threshold Detection of GRB 220325A
  38. GRB 220325A: Enhanced Swift-XRT position
  39. GRB 220325A: MASTER Global Robotic Net optical observations
  40. GRB 220324A: AstroSat CZTI detection
  41. GRB 220325A: Swift detection of a burst
  42. GRB 220323A: AstroSat CZTI detection
  43. GRB 220319A: GRANDMA observations
  44. GRB 220323A: AGILE/MCAL detection
  45. IPN triangulation of GRB 220320A
  46. GRB 220323A: Fermi GBM Final Real-time Localization
  47. GRB 220319A: Swift-BAT refined analysis
  48. GRB 220316A: AstroSat CZTI detection
  49. GRB 220320A: AstroSat CZTI detection
  50. GRB 220317A: Fermi GBM detection
  51. GRB 220321A: Fermi GBM Final Localization
  52. GRB 220319A: MITSuME Akeno optical upper limits
  53. GRB 220319A: LCO Optical Upper Limit
  54. GRB 220319A: Mondy optical uper limit
  55. GRB 220319A: Swift-XRT refined Analysis
  56. GRB 220319A: Enhanced Swift-XRT position
  57. GRB 220319A: MASTER Global Robotic Net optical observations
  58. GRB 220319A: Swift detection of a burst
  59. GRB 220317A: Swift/BAT-GUANO detection outside the coded FOV
  60. GRB 220310A: MITSuME Akeno optical observation
  61. GRB 220317A: Fermi GBM Final Real-time Localization
  62. GRB 220315A: MASTER Global Robotic Net optical observations
  63. GRB 220311A: Fermi GBM observation
  64. GRB 220306B: Swift/UVOT Upper Limits
  65. GRB 220315A: Fermi GBM Final Real-time Localization
  66. GRB 220311A: MITSuME Akeno optical upper limits
  67. IPN triangulation of GRB 220310A
  68. GRB 220310C: Fermi GBM observation
  69. GRB 210722A: TAROT Reunion observatory optical light curve
  70. GRB 210222B: TAROT Reunion observatory optical light curve
  71. GRB 201021C: TAROT Reunion observatory optical light curve
  72. GRB 220310A: K-800 of Terskol observatory optical upper limit
  73. GRB 220310A: [KAO-Egypt] SDSS r, i observation
  74. GRB 220310C: Swift-XRT observations
  75. Konus-Wind detection of GRB 220310A
  76. GRB 220310C: Swift ToO observations
  77. GRB 220310C: Swift/BAT-GUANO candidate arcminute localization
  78. GRB 220311A: MASTER OT retraction
  79. GRB 220311A: A long GRB detected by INTEGRAL
  80. GRB 220311A: Fermi GBM Final Real-time Localization
  81. ZTF22aabjpxh/AT2022cva (GRB 220219B): evidence of supernova in LBT spectra
  82. GRB 220310A: GIT confirmation of optical afterglow.
  83. GRB 220306B: Nanshan/NEXT optical upper limit
  84. ZTF22aabjpxh/AT2022cva (GRB 220219B): continued optical observations, possible photometric evidence of SN
  85. GRB 220310C: Fermi GBM Final Real-time Localization
  86. Fermi GBM Detection of GRB 220308A
  87. GRB 220308A: AGILE detection
  88. GRB 220310A: MASTER optical counterpart detection
  89. GRB 220310A: Swift ToO observations
  90. GRB 220310A: CALET Gamma-Ray Burst Monitor detection
  91. Fermi GRB 220310B: Global MASTER-Net observations report
  92. GRB 220310B: Fermi GBM Final Real-time Localization
  93. GRB 220308B: Fermi GBM detection
  94. GRB 220310A: MAXI/GSC detection
  95. Konus-Wind detection of GRB 220308A
  96. CALET Gamma-Ray Burst Monitor detection of GRB 220308A and its possible precursor
  97. Fermi GRB 220309A: Global MASTER-Net observations report
  98. GRB 220309A: Fermi GBM Final Real-time Localization
  99. GRB 220308A: Swift/BAT-GUANO detection outside the coded FOV
  100. IPN triangulation of GRB 220308A (long / very bright)

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