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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

12407 results found.

  1. Fermi GRB 240422A: Global MASTER-Net observations report
  2. Fermi GRB 240421B: Global MASTER-Net observations report
  3. Swift GRB 240421B: Global MASTER-Net observations report
  4. GRB240421B: BOOTES-5/JGT optical upper limit
  5. GRB 240421B: J-band upper limits from WINTER
  6. GRB 240421B: Swift/UVOT Upper Limits
  7. Fermi GRB 240421A: Global MASTER-Net observations report
  8. EP240420a: TNT upper limit to its optical counterpart
  9. EP240420a: Xinglong decaying optical counterpart
  10. GRB 240421B: Swift detection of a burst
  11. EP240420a: GWAC-F50A optical upper limit
  12. Fermi trigger No 735280430: Global MASTER-Net observations report
  13. GRB240419A: Skynet Optical Afterglow Analysis
  14. IceCube Alert 240419.98: Global MASTER-Net observations report
  15. GRB 240419B: Swift/UVOT Upper Limits
  16. GRB 240419A: Swift/UVOT Upper Limits
  17. Swift GRB 240419B: Global MASTER-Net observations report
  18. EP240414A: Terskol Zeiss-2000 optical upper limit
  19. Swift GRB 240419A: Global MASTER-Net observations report
  20. GRB 240418A: Swift/UVOT Upper Limits
  21. GRB 240419B: Swift detection of a burst
  22. GRB 240411B: Swift/UVOT Detection
  23. EP240417a: YAHPT Optical Upper Limits
  24. GRB240418A: YAHPT Upper Limits
  25. GRB 240419A: VLT/UVES redshift of z = 5.178
  26. Fermi trigger No 735089036: Global MASTER-Net observations report
  27. EP240416a: J-band observations with WINTER
  28. GRB 240419A: Swift detection of a burst
  29. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  30. GRB 240418A: NOT optical upper limits
  31. GRB 240418A: AKO Upper Limit
  32. GRB 240411A: GOTO early optical upper limits
  33. Swift GRB240418.85: Global MASTER-Net observations report
  34. Fermi GRB 240417A: Global MASTER-Net observations report
  35. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  36. EP240416A: Terskol Zeiss-2000 optical upper limit
  37. EP240416A: Khureltogoot optical upper limit
  38. EP240416a: BOOTES-2/TELMA Optical Upper Limit
  39. IceCube-Cascade 240416A: Upper limits from a search for additional neutrino events in IceCube
  40. EP240416A: MASTER optical observations
  41. GRB 240415A: Swift/UVOT Detection
  42. EP240413a: BOOTES-2/TELMA Optical Upper Limit
  43. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  44. EP 240414a: BOOTES-4/MET Optical Upper Limits
  45. Fermi GRB 240415A: Global MASTER-Net observations report
  46. IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
  47. GRB 240414A: Swift/UVOT Detection
  48. GRB 240414A: AKO Optical Upper Limit
  49. EP240413a: Upper limits from GECAM-B Observation
  50. GRB240414A : J-band upper limits from WINTER
  51. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  52. EP240413A: GOTO optical upper limits
  53. Fermi trigger No 734754044: Global MASTER-Net observations report
  54. Swift GRB 240414A: Global MASTER-Net observations report
  55. Fermi-LAT gamma-ray observations of IceCube-240412A
  56. GRB 240414A : MITSuME Akeno optical upper limits
  57. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  58. EP240408a: GSP optical upper limit
  59. IceCube Alert 240412.23: Global MASTER-Net observations report
  60. EP240408a: Upper limits from GECAM-B Observation
  61. EP240408a: BOOTES-6/DPRT optical upper limit
  62. X-ray transient EP240315a: second epoch e-MERLIN radio observations
  63. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  64. Fermi GRB 240408A: Global MASTER-Net observations report
  65. Fermi GRB 240407A: Global MASTER-Net observations report
  66. Fermi-LAT gamma-ray observations of IceCube-240327B
  67. Fermi-LAT gamma-ray observations of IceCube-240327A
  68. Fermi GRB 240405B: Global MASTER-Net observations report
  69. X-ray transient LXT 240402A: WFST optical upper limits​
  70. GRB/FXT 240402B: Kinder optical counterpart candidate
  71. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  72. X-ray transient LXT240402A: AST3-3 optical upper limits
  73. Fermi GRB 240404A: Global MASTER-Net observations report
  74. LXT 240402A: MASTER optical observations with AGN in error-box
  75. GRB 240402B: GWAC-F50A optical upper limit
  76. Fermi trigger No 733808041: Global MASTER-Net observations report
  77. Fermi GRB 240402A: Global MASTER-Net observations report
  78. X-ray transient EP240331a: Kinder optical upper limits
  79. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  80. EP240331A: MASTER optical observations
  81. X-ray transient EP20240331a: MeerLICHT optical upper limits
  82. IceCube-240327B: Upper limits from a search for additional neutrino events in IceCube
  83. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  84. Integral GRB240401.69: Global MASTER-Net observations report
  85. Fermi trigger No 733366352: Global MASTER-Net observations report
  86. Fermi GRB 240329A: Global MASTER-Net observations report
  87. Fermi GRB 240328B: Global MASTER-Net observations report
  88. Fermi GRB 240328A: Global MASTER-Net observations report
  89. IceCube Alert 240327.68: Global MASTER-Net observations report
  90. X-ray transient EP 240315a: Second epoch Chandra observations
  91. Fermi trigger No 733097506: Global MASTER-Net observations report
  92. X-ray transient EP240315a: e-MERLIN radio observations
  93. Transient EPW20240219aa: REM optical/NIR further observations
  94. Fermi trigger No 733092476: Global MASTER-Net observations report
  95. Fermi trigger No 732937833: Global MASTER-Net observations report
  96. Fermi GRB 240320A: Global MASTER-Net observations report
  97. Fermi trigger No 732657380: Global MASTER-Net observations report
  98. X-ray transient EP240315a/AT2024eju: TShAO (Zeiss-1000) observatory optical upper limit
  99. Fermi GRB 240318A: Global MASTER-Net observations report
  100. X-ray transient EP240315a: Kitab observatory optical upper limitns

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