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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"

22194 results found.

  1. GRB 221009A: VLT spectroscopic detection of the host galaxy
  2. GRB 221009A: ATCA detection
  3. GRB 221009A: ALMA and ACA detections
  4. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  5. GRB 221009A: Large Binocular Telescope Observatory optical afterglow detection
  6. GRB 221009A: Pan-STARRS optical photometry
  7. GRB 221009A: VLA detection
  8. GRB 221009A: continued REM optical/NIR observations and evidence for an achromatic steepening in the afterglow light curve
  9. GRB 221009A: OHP optical observations
  10. GRB221009A: RTT-150 optical observations
  11. GRB 221009A: Gemini-South Infrared Afterglow Detection
  12. GRB221009A: Gemini-South Optical Afterglow Detection
  13. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  14. GRB221009A: Detection as sudden ionospheric disturbances (SID)
  15. GRB221009A: RTT-150 optical observations
  16. MAXI GRB 221006A: Redshifts of the possible host galaxies
  17. GRB 221009A: MeerKAT detection
  18. GRB 221009A: Lowell Discovery Telescope Afterglow Detection
  19. GRB221009A: LCOGT Continued Observations - Optical Upper Limits
  20. GRB 221009A/Swift J1913.1+1946: low-frequency ASKAP observations
  21. Fermi trigger No 687345829: Global MASTER-Net observations report
  22. Fermi trigger No 687344475: Global MASTER-Net observations report
  23. Fermi trigger No 687340841: Global MASTER-Net observations report
  24. Fermi trigger No 687337536: Global MASTER-Net observations report
  25. GRB 221006A: Swift-XRT afterglow detection
  26. GRB 221009A: Sayan observatory 1.6-m telescope observations
  27. Fermi trigger No 687281393: Global MASTER-Net observations report
  28. Integral GRB221013.04: Global MASTER-Net observations report
  29. Integral GRB221013.00: Global MASTER-Net observations report
  30. Integral GRB221012.99: Global MASTER-Net observations report
  31. Integral GRB221012.94: Global MASTER-Net observations report
  32. Integral GRB221012.91: Global MASTER-Net observations report
  33. Integral GRB221012.88: Global MASTER-Net observations report
  34. Integral GRB221012.87: Global MASTER-Net observations report
  35. Integral GRB221012.77: Global MASTER-Net observations report
  36. Integral GRB221012.74: Global MASTER-Net observations report
  37. Integral GRB221012.72: Global MASTER-Net observations report
  38. Integral GRB221012.71: Global MASTER-Net observations report
  39. Integral GRB221012.68: Global MASTER-Net observations report
  40. Integral GRB221012.68: Global MASTER-Net observations report
  41. Integral GRB221012.98: Global MASTER-Net observations report
  42. Afterglow limits of GRB 221006A from OHP
  43. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  44. GRB 221009A/Swift J1913.1+1946: SMA observations
  45. INTEGRAL shows increasing activity in SGR J1935+2154
  46. GRB 221009A: COATLI Continued Monitoring of the Afterglow
  47. Integral GRB221012.63: Global MASTER-Net observations report
  48. Integral GRB221012.61: Global MASTER-Net observations report
  49. Integral GRB221012.60: Global MASTER-Net observations report
  50. Integral GRB221012.53: Global MASTER-Net observations report
  51. GRB 221009A/Swift J1913.1+1946: eMERLIN observations
  52. Fermi trigger No 687205006: Global MASTER-Net observations report
  53. INTEGRAL detection of a burst from SGR J1935+2154
  54. GRB 221009A: NuSTAR Detection
  55. GRB 221009A: NICER follow-up observations
  56. GRB 221009A: LCOGT Optical Afterglow Detection
  57. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  58. GRB 221009A: planned observation with the Imaging X-ray Polarimetry Explorer (IXPE)
  59. Fermi trigger No 687190301: Global MASTER-Net observations report
  60. GRB 221009A: Sintez-Newton/CrAO optical observations
  61. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  62. GRB 221006A: Swift ToO observations
  63. GRB 221009A: BlackGEM optical observations
  64. GRB 221009A: NOEMA mm detection
  65. GRB 221006A: CALET Gamma-Ray Burst Monitor detection
  66. Integral GRB221010.89: Global MASTER-Net observations report
  67. Fermi trigger No 687077239: Global MASTER-Net observations report
  68. GRB 221009A: Continued Swift/XRT observations
  69. GRB 221009A/Swift J1913.1+1946: Assy optical afterglow observation
  70. GRB 221009A/Swift J1913.1+1946: Lick/Nickel telescope optical observations
  71. GRB 221009A: Lulin SLT-40cm optical observations
  72. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  73. GRB221009A/Swift J1913.1+1946: SRG/ART-XC observation
  74. GRB221009A/Swift J1913.1+1946: INTEGRAL SPI/ACS observations
  75. GRB 221009A: Fermi-LAT refined analysis
  76. GRB 221009: Swift/UVOT Detection
  77. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  78. GRB 221009A or Swift J1913.1+1946: PRIME near-infrared detection
  79. GRB 221009A/Swift J1913.1+1946: AMI-LA observations
  80. GRB 221009A: REM optical and NIR detection of the afterglow
  81. Swift J1913.1+1946: Early Optical Photometry
  82. GRB 221009A: Redshift from X-shooter/VLT
  83. GRB 221009A: Nanshan/NEXT photometry and Xinglong-2.16m spectroscopy
  84. GRB 221009A (Swift J1913.1+1946): MeerLICHT observations
  85. GRB 221009A (Swift J1913.1+1946): Mondy optical observations
  86. GRB 221009A BOOTES-2/TELMA and OSN optical detections
  87. Swift J1913.1+1946: Optical photometry
  88. Fermi trigger No 687014224: Global MASTER-Net observations report
  89. Swift J1913.1+1946: Liverpool Telescope imaging and spectroscopy
  90. GRB 221008A: Swift-XRT observations
  91. GRB 221008A: Tiled Swift observations
  92. GRB 220915A: Detection by GRBAlpha
  93. GRB 221006A: Swift-XRT observations
  94. GRB 221006A: Tiled Swift observations
  95. Fermi trigger No 686588176: Global MASTER-Net observations report
  96. GRB220927A: Detection by GRBAlpha
  97. GRB 220921A: ATCA detection of radio counterpart
  98. Fermi trigger No 686403226: Global MASTER-Net observations report
  99. Fermi trigger No 686350260: Global MASTER-Net observations report
  100. Konus-Wind detection of GRB 220930A

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