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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"

22095 results found.

  1. GRB 240122A: ATCA detection of radio counterpart
  2. GRB240122A: PRIME near infrared detection
  3. GRB 240123B: Swift/BAT-GUANO detection of a long burst
  4. Fermi-LAT gamma-ray observations of IceCube-240123A
  5. GRB 240123A: further SAO RAS optical observations
  6. IceCube Alert 240123.48: Global MASTER-Net observations report
  7. GRB 240123A: Mondy continued optical observations and the PL decay index
  8. GRB 240123A: SAO RAS optical observations
  9. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  10. Fermi GRB 240123B: Global MASTER-Net observations report
  11. GRB 240122A: Swift/UVOT Upper Limits
  12. GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
  13. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  14. GRB 240118A: Swift/UVOT Upper Limits
  15. GRB 240123A: Mondy optical afterglow observations
  16. Swift GRB240123.46: Global MASTER-Net observations report
  17. GRB 240122A: Swift-XRT afterglow detection
  18. GRB 240122A: VLT/X-shooter redshift confirmation
  19. GRB 240122A: LT non-detection of GOTO candidate counterpart confirms fading
  20. GRB 240122A: GOTO optical counterpart candidate
  21. GRB 240122A: Tiled Swift observations
  22. GRB 240118A: Mondy optical observations
  23. GRB 240118A: Swift-XRT afterglow detection
  24. Fermi GRB 240119A: Global MASTER-Net observations report
  25. IceCube-240105A: Detection of NIR flare of PKS 0446+11 with WINTER
  26. GRB 240118C: Swift/BAT-GUANO detection of a burst
  27. GRB 240118A: Swift ToO observations
  28. Fermi GRB 240118B: Global MASTER-Net observations report
  29. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  30. Konus-Wind detection of GRB 240118A
  31. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240118A
  32. LAT GRB240118.08: Global MASTER-Net observations report
  33. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  34. Swift Triggers 1209369 and 1209370 are not astrophysical events
  35. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  36. Integral GRB240115.70: Global MASTER-Net observations report
  37. Fermi GRB 240115B: Global MASTER-Net observations report
  38. Fermi GRB 240115A: Global MASTER-Net observations report
  39. GRB 240112C: Swift/UVOT Detection
  40. Fermi trigger No 726773850: Global MASTER-Net observations report
  41. GRB 240112C: SAO RAS optical observations
  42. Fermi GRB 240112D: Global MASTER-Net observations report
  43. Fermi trigger No 726774492: Global MASTER-Net observations report
  44. Swift GRB 240112C: Global MASTER-Net observations report
  45. Fermi GRB 240112B: Global MASTER-Net observations report
  46. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 0446+11, located inside the IceCube-240105A error region
  47. GRB 231214A: ATCA Radio Upper Limits
  48. IceCube-240105A: Three candidates from the Zwicky Transient Facility
  49. GRB 231215A: radio detection with the VLA
  50. GRB 230818A: further radio observations with the VLA
  51. GRB 230812B: further radio observations with the VLA
  52. Swift GRB240109.17: Global MASTER-Net observations report
  53. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  54. IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources
  55. Fermi trigger No 726347794: Global MASTER-Net observations report
  56. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  57. Fermi trigger No 726194053: Global MASTER-Net observations report
  58. IceCube Alert 240105.52: Global MASTER-Net observations report
  59. GRB 240101A: 1.3m DFOT optical observations
  60. GRB 240102A: 1.3m DFOT optical upper limit
  61. GRB 240101B: 1.3m DFOT optical upper limit
  62. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  63. GRB 231220A: Swift-UVOT upper limit
  64. GRB 240102A: Swift/UVOT Upper Limits
  65. Fermi trigger No 725857207: Global MASTER-Net observations report
  66. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  67. GRB 240101A: Terskol Zeiss-2000 optical observations
  68. GRB 240101B: Swift/UVOT Upper Limits
  69. GRB 240101A: Swift/UVOT Upper Limits
  70. Swift GRB240101.85: Global MASTER-Net observations report
  71. Fermi trigger No 725806648: Global MASTER-Net observations report
  72. GRB 231230A: GOTO optical upper limits
  73. GRB 231230A: Swift/UVOT Upper Limits
  74. GRB 231230A: NOT optical upper limits
  75. Fermi trigger No 725592555: Global MASTER-Net observations report
  76. Swift GRB231230.06: Global MASTER-Net observations report
  77. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  78. Fermi trigger No 725143760: Global MASTER-Net observations report
  79. GRB 231222B: Swift-XRT afterglow detection
  80. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  81. Fermi trigger No 724921799: Global MASTER-Net observations report
  82. LAT GRB231222.31: Global MASTER-Net observations report
  83. GRB 231222A: Tiled Swift observations
  84. IceCube-231211A: GRANDMA observations of PKS2047+098
  85. GRB 231220A: Swift-XRT follow-up observations
  86. GRB 231220A: Swift ToO observations
  87. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  88. Fermi trigger No 724781422: Global MASTER-Net observations report
  89. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  90. Fermi trigger No 724698747: Global MASTER-Net observations report
  91. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  92. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  93. GRB 231215A: AMI-LA radio detection
  94. GRB 231216A: Nanshan/HMT optical upper limit
  95. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  96. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  97. GRB 231216A: REM NIR upper limits
  98. GRB 231216A: Swift/UVOT Upper Limits
  99. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  100. GRB 231216A: GIT optical upper limit

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