Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

32688 results found.

  1. GRB 221009A: Gemini-South Infrared Afterglow Detection
  2. GRB221009A: Gemini-South Optical Afterglow Detection
  3. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  4. GRB 221009A: Gamma-ray Detection by SIRI-2
  5. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  6. GRB221009A: RTT-150 optical observations
  7. MAXI GRB 221006A: Redshifts of the possible host galaxies
  8. GRB 221009A: search for neutrinos with KM3NeT
  9. GRB 221009A: MeerKAT detection
  10. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  11. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  12. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  13. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  14. GRB 221006A: Swift-XRT afterglow detection
  15. GRB 221009A: MITSuME Okayama optical observation
  16. GRB 221009A: Sayan observatory 1.6-m telescope observations
  17. GRB 221009A: GMG observation
  18. Afterglow limits of GRB 221006A from OHP
  19. GRB221009A: optical afterglow measurements from Konkoly Observatory
  20. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  21. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  22. INTEGRAL detection of a burst from SGR J1935+2154
  23. GRB 221009A: NuSTAR Detection
  24. GRB 221009A: NICER follow-up observations
  25. GRB 221009A: LCOGT Optical Afterglow Detection
  26. GRB 221009A: COATLI Detection of the Afterglow
  27. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  28. GRB 221009A (Swift J1913.1+1946): Swift-BAT refined analysis
  29. GRB 221009A: Detection by GRBAlpha
  30. GRB 221009A: Sintez-Newton/CrAO optical observations
  31. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  32. GRB 221006A: Swift ToO observations
  33. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  34. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  35. GRB 221009A: BlackGEM optical observations
  36. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  37. GRB 221009A: NOEMA mm detection
  38. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 221009A: Continued Swift/XRT observations
  40. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  41. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  42. Konus-Wind detection of GRB 221009A
  43. GRB 221009A: Lulin SLT-40cm optical observations
  44. Swift J1913.1+1946: New Photometry
  45. GRB 221009A: Upper limits from a neutrino search with IceCube
  46. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  47. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  48. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  49. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  50. ​GRB 221009A: Multi-color detection of the optical
  51. GRB 221009A: Fermi-LAT refined analysis
  52. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection
  53. GRB 221009: Swift/UVOT Detection
  54. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  55. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  56. GRB 221009A: REM optical and NIR detection of the afterglow
  57. GRB 221009A: Swift-XRT refined Analysis
  58. GRB 221009A (Swift J1913.1+1946): AGILE/MCAL detection
  59. Swift J1913.1+1946: Early Optical Photometry
  60. GRB 221009A: Redshift from X-shooter/VLT
  61. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  62. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  63. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  64. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  65. GRB 221009A: Fermi GBM observation
  66. IPN triangulation of extremely bright GRB 221009A
  67. Swift J1913.1+1946: Optical photometry
  68. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  69. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  70. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  71. GRB 221009A: Swift detected transient may be GRB
  72. GRB 221008A: Swift-XRT observations
  73. GRB 221008A: Tiled Swift observations
  74. GRB 221006A: Swift-XRT observations
  75. GRB 221006A: Tiled Swift observations
  76. GRB 220930A: MITSuME Akeno optical upper limits
  77. GRB 220912A: Detection by VZLUSAT-2
  78. GRB220927A: Detection by GRBAlpha
  79. GRB 220921A: ATCA detection of radio counterpart
  80. GRB 220930A: AbAO Optical Upper Limit
  81. Konus-Wind detection of GRB 220930A
  82. GRB 220930A: AstroSat CZTI detection
  83. GRB 220930A: Swift-BAT refined analysis
  84. GRB 220930A: Swift-XRT refined Analysis
  85. GRB 220930A: LCOGT Optical Upper Limits
  86. GRB 220930A: Swift/UVOT Upper Limits
  87. Swift GRB 220930A: Global MASTER-Net observations report
  88. GRB 220930A: COATLI Upper Limits
  89. Fermi-LAT gamma-ray observations of IceCube-220928A
  90. Konus-Wind detection of GRB 220927A
  91. Fermi GRB 220927A: Global MASTER-Net observations report
  92. IPN triangulation of GRB 220927A (long)
  93. GRB 220921A: LCOGT Optical Observations
  94. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  95. GRB 220924A: Fermi GBM detection
  96. Swift Trigger 1125354 (GRB 220926A) is not a GRB
  97. Swift GRB 220926A: Global MASTER-Net observations report
  98. Analysis of long GRB 220926B detected by INTEGRAL
  99. Fermi GRB 220925A: Global MASTER-Net observations report
  100. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV

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