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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"

21994 results found.

  1. GRB 230812B: Tautenburg observations
  2. GRB 230812B: AMI-LA radio detection of afterglow candidate
  3. GRB 230812B: continued AbAO optical afterglow observations
  4. GRB 230812B: Optical observaions from Rozhen Observatory
  5. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  6. GRB 230812B: further SAO RAS optical observations
  7. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  8. GRB 230812B: CrAO ZTSh optical observations
  9. GRB 230812B: Koshka Zeiss-1000 optical observations
  10. GRB 230812B: Leavitt Observatory optical observations
  11. GRB 230812B : optical observations from Observatoire de Haute-Provence
  12. GRB 230812B: Bassano Bresciano Observatory optical observations
  13. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  14. GRB 230812B: OASDG optical observations
  15. GRB 230812B: AbAO optical observations
  16. GRB 230812B: Montarrenti Observatory optical observations
  17. GRB 230812B: SAO RAS optical observations
  18. GRB 230812B: GMG - GRANDMA observations
  19. GRB 230812B: Swift-XRT afterglow detection
  20. GRB 230812: Swift/UVOT Detection
  21. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  22. GRB 230812B: KAIT Optical Afterglow Candidate
  23. LAT GRB230812.79: Global MASTER-Net observations report
  24. Fermi GRB 230812B: Global MASTER-Net observations report
  25. GRB 230812B: Tiled Swift observations
  26. ZTF23aaoohpy/AT2023lcr: JWST spectroscopy confirmation of an associated type Ic-BL supernova
  27. Fermi trigger No 713525317: Global MASTER-Net observations report
  28. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  29. GRB 230808A: Swift/BAT-GUANO detection of a burst
  30. Fermi trigger No 713136868: Global MASTER-Net observations report
  31. Fermi trigger No 713205976: Global MASTER-Net observations report
  32. ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova
  33. transient SPT-SVJ025406.5-702837: ATCA follow-up observations
  34. Fermi GRB 230807A: Global MASTER-Net observations report
  35. Fermi trigger No 713134237: Global MASTER-Net observations report
  36. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  37. GRB 230805B : OHP/T193 optical upper limit
  38. GRB 230805B: Swift/UVOT Upper Limits
  39. Fermi trigger No 712991593: Global MASTER-Net observations report
  40. GRB 230805B: Bassano Bresciano observatory upper limit
  41. Fermi trigger No 712987357: Global MASTER-Net observations report
  42. GRB 230805B: NOT optical afterglow confirmation
  43. Fermi GRB 230805A: Global MASTER-Net observations report
  44. GRB 230805B: SAO RAS optical observations
  45. Fermi trigger No 712927418: Global MASTER-Net observations report
  46. Swift GRB 230805B: Global MASTER-Net observations report
  47. Fermi trigger No 712798043: Global MASTER-Net observations report
  48. GRB 230802A: Swift/UVOT Upper Limits
  49. Fermi trigger No 712718833: Global MASTER-Net observations report
  50. Fermi trigger No 712713532: Global MASTER-Net observations report
  51. Fermi trigger No 712651827: Global MASTER-Net observations report
  52. Swift GRB 230802A: Global MASTER-Net observations report
  53. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  54. LIGO/Virgo/KAGRA S230802aq: Coverage and upper limits from MAXI/GSC observations
  55. IceCube-230724A: JCMT/SCUBA-2 submm observations
  56. IceCube-230707A: JCMT/SCUBA-2 submm observations
  57. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  58. LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations
  59. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  60. Fermi trigger No 712390645: Global MASTER-Net observations report
  61. Fermi-LAT gamma-ray observations of IceCube-230727A
  62. Fermi trigger No 712306969: Global MASTER-Net observations report
  63. IceCube-230727A: No candidates from the Zwicky Transient Facility
  64. GRB 230728A: Swift/UVOT Upper Limits
  65. GRB 230728A: NOT optical observations and possible host galaxy
  66. IceCube-230724A: No counterparts from the Zwicky Transient Facility
  67. Swift GRB230728.12: Global MASTER-Net observations report
  68. GRB 230727A: Swift/BAT-GUANO detection of a burst
  69. Fermi-LAT gamma-ray observations of IceCube-230725A
  70. Fermi-LAT gamma-ray observations of IceCube-230724A
  71. Fermi trigger No 712143685: Global MASTER-Net observations report
  72. Integral GRB230726.26: Global MASTER-Net observations report
  73. GRB 230723B: Further CAHA observations and host galaxy detection
  74. GRB 230723B: ATCA rapid radio follow-up
  75. Integral GRB230725.99: Global MASTER-Net observations report
  76. IceCube Alert 230725.90: Global MASTER-Net observations report
  77. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  78. GRB 230723B: Leavitt Observatory upper limit
  79. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  80. GRB 230723B: Montarrenti Observatory upper limit
  81. GRB 230723B: Optical afterglow candidate from CAHA
  82. GRB 230723B: Bassano Bresciano Observatory upper limit
  83. GRB 230723B: non-detections from Observatoire de Haute-Provence
  84. IceCube Alert 230724.08: Global MASTER-Net observations report
  85. Fermi trigger No 711853834: Global MASTER-Net observations report
  86. Fermi trigger No 711805358: Global MASTER-Net observations report
  87. GRB 230723B: Optical limit from CAHA
  88. GRB 230723B: Swift/UVOT Upper Limits
  89. Swift GRB 230723B: Global MASTER-Net observations report
  90. GRB 230723B: Swift-XRT observations
  91. Fermi GRB 230723A: Global MASTER-Net observations report
  92. Swift GRB230720.30: Global MASTER-Net observations report
  93. Fermi trigger No 711088412: Global MASTER-Net observations report
  94. Fermi GRB 230713A: Global MASTER-Net observations report
  95. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  96. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  97. Fermi trigger No 710741042: Global MASTER-Net observations report
  98. IceCube-230707A: No candidates detected by Swift-XRT
  99. IceCube-230707A: No candidates from the Zwicky Transient Facility
  100. Fermi-LAT gamma-ray observations of IceCube-230708A

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