Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

22063 results found.

  1. Integral GRB221012.91: Global MASTER-Net observations report
  2. Integral GRB221012.88: Global MASTER-Net observations report
  3. Integral GRB221012.87: Global MASTER-Net observations report
  4. Integral GRB221012.77: Global MASTER-Net observations report
  5. Integral GRB221012.74: Global MASTER-Net observations report
  6. Integral GRB221012.72: Global MASTER-Net observations report
  7. Integral GRB221012.71: Global MASTER-Net observations report
  8. Integral GRB221012.68: Global MASTER-Net observations report
  9. Integral GRB221012.68: Global MASTER-Net observations report
  10. Integral GRB221012.98: Global MASTER-Net observations report
  11. Afterglow limits of GRB 221006A from OHP
  12. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  13. GRB 221009A/Swift J1913.1+1946: SMA observations
  14. INTEGRAL shows increasing activity in SGR J1935+2154
  15. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  16. Integral GRB221012.63: Global MASTER-Net observations report
  17. Integral GRB221012.61: Global MASTER-Net observations report
  18. Integral GRB221012.60: Global MASTER-Net observations report
  19. Integral GRB221012.53: Global MASTER-Net observations report
  20. GRB 221009A/Swift J1913.1+1946: eMERLIN observations
  21. Fermi trigger No 687205006: Global MASTER-Net observations report
  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. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  27. GRB 221009A: planned observation with the Imaging X-ray Polarimetry Explorer (IXPE)
  28. Fermi trigger No 687190301: Global MASTER-Net observations report
  29. GRB 221009A: Sintez-Newton/CrAO optical observations
  30. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  31. GRB 221006A: Swift ToO observations
  32. GRB 221009A: BlackGEM optical observations
  33. GRB 221009A: NOEMA mm detection
  34. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  35. Integral GRB221010.89: Global MASTER-Net observations report
  36. Fermi trigger No 687077239: Global MASTER-Net observations report
  37. GRB 221009A: Continued Swift/XRT observations
  38. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  39. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  40. GRB 221009A: Lulin SLT-40cm optical observations
  41. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  42. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  43. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  44. GRB 221009A: Fermi-LAT refined analysis
  45. GRB 221009: Swift/UVOT Detection
  46. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  47. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  48. GRB 221009A/Swift J1913.1+1946: AMI-LA observations
  49. GRB 221009A: REM optical and NIR detection of the afterglow
  50. Swift J1913.1+1946: Early Optical Photometry
  51. GRB 221009A: Redshift from X-shooter/VLT
  52. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  53. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  54. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  55. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  56. Swift J1913.1+1946: Optical photometry
  57. Fermi trigger No 687014224: Global MASTER-Net observations report
  58. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  59. GRB 221008A: Swift-XRT observations
  60. GRB 221008A: Tiled Swift observations
  61. GRB 220915A: Detection by GRBAlpha
  62. GRB 221006A: Swift-XRT observations
  63. GRB 221006A: Tiled Swift observations
  64. Fermi trigger No 686588176: Global MASTER-Net observations report
  65. GRB220927A: Detection by GRBAlpha
  66. GRB 220921A: ATCA detection of radio counterpart
  67. Fermi trigger No 686403226: Global MASTER-Net observations report
  68. Fermi trigger No 686350260: Global MASTER-Net observations report
  69. Konus-Wind detection of GRB 220930A
  70. GRB 220930A: Swift/UVOT Upper Limits
  71. Swift GRB 220930A: Global MASTER-Net observations report
  72. Fermi-LAT gamma-ray observations of IceCube-220928A
  73. Konus-Wind detection of GRB 220927A
  74. Fermi GRB 220927A: Global MASTER-Net observations report
  75. GRB 220921A: LCOGT Optical Observations
  76. GRB 220611A: Host galaxy redshift from VLT/X-shooter
  77. Integral GRB220926.44: Global MASTER-Net observations report
  78. Swift GRB220926.34: Global MASTER-Net observations report
  79. Swift GRB 220926A: Global MASTER-Net observations report
  80. Fermi GRB 220925A: Global MASTER-Net observations report
  81. GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
  82. GRB 220921A: further MeerLICHT observations
  83. Fermi trigger No 685748699: Global MASTER-Net observations report
  84. Swift GRB220923.47: Global MASTER-Net observations report
  85. GRB 220921A: ALMA detection
  86. GRB 220921A: DDOTI Detection of the Afterglow
  87. Konus-Wind detection of GRB 220921A
  88. IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
  89. GRB 220921A: MeerLICHT afterglow observations
  90. GRB 220921A: Swift-XRT Observations
  91. GRB 220921A: MASTER OT inside Fermi-LAT error-box
  92. LAT GRB220921.46: Global MASTER-Net observations report
  93. GRB 220921A: Tiled Swift observations
  94. Fermi trigger No 685452089: Global MASTER-Net observations report
  95. Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
  96. IceCube Alert 220918.53: Global MASTER-Net observations report
  97. Fermi trigger No 684894705: Global MASTER-Net observations report
  98. Fermi trigger No 684927323: Global MASTER-Net observations report
  99. Fermi trigger No 684911625: Global MASTER-Net observations report
  100. Konus-Wind detection of GRB 220910A

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