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"

30514 results found.

  1. GRB 221016A: Swift-XRT refined Analysis
  2. Konus-Wind detection of GRB 221016A
  3. GRB 221016A: Fermi GBM observation
  4. GRB 220926B: Detection by GRBAlpha
  5. GRB 221016A: z-band upper limit, possible afterglow brightening
  6. GRB 221016A: LCOGT Optical Afterglow Detection
  7. GRB 221009A: Faulkes Telescope North continued optical afterglow follow-up
  8. Konus-Wind detection of a short burst coincident with a bright radio burst from SGR 1935+2154
  9. GRB 221009A: continued Assy optical afterglow observations, possible SN evidence
  10. Konus-Wind observation of the recent SGR 1935+2154 activity
  11. GRB 221009A: LEIA X-ray Afterglow Detection
  12. GRB 221009A: ATCA radio spectrum
  13. GRB 221009A: VLT spectroscopic detection of the host galaxy
  14. Fermi Gamma-ray Burst Monitor detections of SGR 1935+2154
  15. GRB 221009A: ATCA detection
  16. GRB 221009A: Armchair Energetics
  17. GRB 221009A: ALMA and ACA detections
  18. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  19. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  20. GRB 221009A: Pan-STARRS optical photometry
  21. GRB 221009A: VLA detection
  22. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  23. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  24. GRB 221009A: OHP optical observations
  25. GRB221009A: RTT-150 optical observations
  26. GRB 221009A: HEBS detection
  27. GRB 221009A: Gemini-South Infrared Afterglow Detection
  28. GRB221009A: Gemini-South Optical Afterglow Detection
  29. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  30. GRB 221009A: Gamma-ray Detection by SIRI-2
  31. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  32. GRB221009A: RTT-150 optical observations
  33. MAXI GRB 221006A: Redshifts of the possible host galaxies
  34. GRB 221009A: search for neutrinos with KM3NeT
  35. GRB 221009A: MeerKAT detection
  36. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  37. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  38. Fermi Gamma-ray Burst Monitor continues to detect SGR 1935+2154
  39. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  40. GRB 221006A: Swift-XRT afterglow detection
  41. GRB 221009A: MITSuME Okayama optical observation
  42. GRB 221009A: Sayan observatory 1.6-m telescope observations
  43. GRB 221009A: GMG observation
  44. Afterglow limits of GRB 221006A from OHP
  45. GRB221009A: optical afterglow measurements from Konkoly Observatory
  46. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  47. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  48. INTEGRAL detection of a burst from SGR J1935+2154
  49. GRB 221009A: NuSTAR Detection
  50. GRB 221009A: NICER follow-up observations
  51. GRB 221009A: LCOGT Optical Afterglow Detection
  52. GRB 221009A: COATLI Detection of the Afterglow
  53. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  54. GRB 221009A (Swift J1913.1+1946): Swift-BAT refined analysis
  55. GRB 221009A: Detection by GRBAlpha
  56. GRB 221009A: Sintez-Newton/CrAO optical observations
  57. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  58. GRB 221006A: Swift ToO observations
  59. Swift/XRT discovery of multiple dust-scattering X-ray rings around GRB 221009A
  60. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  61. GRB 221009A: BlackGEM optical observations
  62. LHAASO observed GRB 221009A with more than 5000 VHE photons up to around 18 TeV
  63. GRB 221009A: NOEMA mm detection
  64. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  65. GRB 221009A: Continued Swift/XRT observations
  66. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  67. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  68. Konus-Wind detection of GRB 221009A
  69. GRB 221009A: Lulin SLT-40cm optical observations
  70. Swift J1913.1+1946: New Photometry
  71. GRB 221009A: Upper limits from a neutrino search with IceCube
  72. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  73. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  74. GRB 221009A / Swift J1913.1+1946: GIT detection of the optical afterglow
  75. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  76. ​GRB 221009A: Multi-color detection of the optical
  77. GRB 221009A: Fermi-LAT refined analysis
  78. GRB 221009A (Swift J1913.1+1946): AGILE/GRID detection
  79. GRB 221009: Swift/UVOT Detection
  80. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  81. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  82. GRB 221009A: REM optical and NIR detection of the afterglow
  83. GRB 221009A: Swift-XRT refined Analysis
  84. GRB 221009A (Swift J1913.1+1946): AGILE/MCAL detection
  85. Swift J1913.1+1946: Early Optical Photometry
  86. GRB 221009A: Redshift from X-shooter/VLT
  87. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  88. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  89. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  90. Swift J1913.1+1946 : Pre-discovery limits from ZTF
  91. GRB 221009A: Fermi GBM observation
  92. IPN triangulation of extremely bright GRB 221009A
  93. Swift J1913.1+1946: Optical photometry
  94. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  95. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  96. GRB 221009A: Fermi GBM detection of an extraordinarily bright GRB
  97. GRB 221009A: Swift detected transient may be GRB
  98. GRB 221008A: Swift-XRT observations
  99. GRB 221008A: Tiled Swift observations
  100. GRB 221006A: Swift-XRT observations

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