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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').
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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"

21982 results found.

  1. Fermi trigger No 743345551: Global MASTER-Net observations report
  2. Fermi-LAT gamma-ray observations of IceCube-240721A
  3. Fermi trigger No 743219692: Global MASTER-Net observations report
  4. IceCube Alert 240721.68: Global MASTER-Net observations report
  5. Fermi GRB 240720A: Global MASTER-Net observations report
  6. Swift GRB240720.02: Global MASTER-Net observations report
  7. Fermi GRB 240718A: Global MASTER-Net observations report
  8. LAT GRB240718.27: Global MASTER-Net observations report
  9. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  10. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  11. GRB 240715A: Swift/UVOT observations of the XRT sources.
  12. GRB 240715A: Swift-XRT observations
  13. GRB240713A: Swift/UVOT Upper LImits
  14. EP240708a: X-ray follow-up observations with Swift/XRT
  15. GRB 240713A: Swift-XRT observations
  16. GRB 240713A: LAST optical upper limit
  17. GRB 240715A: Swift ToO observations
  18. Fermi GRB 240715A: Global MASTER-Net observations report
  19. GRB 240712A ATCA radio observations
  20. GRB240715A: GRANDMA Optical Upper Limits
  21. GW s240422ed: Swift UVOT follow-up
  22. GRB 240712A: Swift/UVOT Upper Limits
  23. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  24. The EP-WXT source triggered on July 14th is likely a flaring star
  25. GRB 240713A: Tiled Swift observations
  26. GRB 240713A: J-band upper limit from WINTER
  27. GRB 240713A: JinShan optical upper limits
  28. GRB 240713A: OHP/T120 optical upper limit
  29. GRB240713A: Optical upper limit with Kinder observations
  30. Fermi Sub-threshold Observation of GRB240713A
  31. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  32. EP240708a: GSP optical upper limit
  33. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  34. Fermi trigger No 742405878: Global MASTER-Net observations report
  35. Fermi trigger No 742317942: Global MASTER-Net observations report
  36. Fermi GRB 240710A: Global MASTER-Net observations report
  37. EP240708a: NOT optical observations
  38. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  39. EP240708a: Optical upper limits with Kinder observations
  40. EP240708a: EP-WXT detection of a fast X-ray transient
  41. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  42. EP240703b: GSP optical upper limit
  43. EP240703b: TRT optical upper limits
  44. EP240703a: TRT further optical observation
  45. EP240702a: TRT optical upper limits
  46. EP240703a and EP240703b: Swift/XRT upper limits
  47. EP240703a: BTA observations
  48. EP240703c: Kinder optical follow-up and Swift XRT observations
  49. EP240703a: Liverpool Telescope optical follow-up observations
  50. EP240703a: Kinder optical follow-up observations
  51. EP240703c: EP-WXT detection of an X-ray transient
  52. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  53. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  54. EP240703b: EP-WXT detection of a fast X-ray transient
  55. EP240703a: EP-WXT detection of a fast X-ray transient
  56. EP240702a: GSP optical upper limit
  57. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  58. Fermi GRB 240702A: Global MASTER-Net observations report
  59. EP240702a: EP-WXT detection of a fast X-ray transient
  60. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  61. Fermi trigger No 741448122: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  63. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  64. Fermi trigger No 741356809: Global MASTER-Net observations report
  65. Fermi GRB 240629A: Global MASTER-Net observations report
  66. Fermi trigger No 741296200: Global MASTER-Net observations report
  67. Fermi trigger No 741251380: Global MASTER-Net observations report
  68. GRB 240615A: SAI CMO J- band observations
  69. Fermi trigger No 741211696: Global MASTER-Net observations report
  70. EP240626a: Montarrenti Observatory optical upper limit
  71. EP240625a: GRANDMA Optical Upper Limits
  72. EP240626a: EP-WXT detection of a fast X-ray transient
  73. Fermi GRB 240625B: Global MASTER-Net observations report
  74. EP240625a: NOT optical counterpart candidate
  75. EP240625a: EP-WXT detection of a fast X-ray transient
  76. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  77. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  78. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  79. Swift GRB 240624A: Global MASTER-Net observations report
  80. GRB240615A: Gemini-North observations of the BAT and XRT positions
  81. Fermi GRB 240624A: Global MASTER-Net observations report
  82. Fermi trigger No 740949590: Global MASTER-Net observations report
  83. GRB240615A: Gemini-North observations of the BAT and XRT positions
  84. GRB 240619A: detection of a radio counterpart with AMI-LA
  85. EP240618a: NOT further optical observations
  86. GRB 240619A: J-band detection with WINTER
  87. Fermi trigger No 740744838: Global MASTER-Net observations report
  88. EP240618a: NOT optical counterpart candidate
  89. GRB 240529A: JinShan optical observations
  90. EP240618a: GSP optical upper limit
  91. EP240617a: tentative Swift/XRT detection of the afterglow
  92. GRB 240619A: Swift-XRT probable afterglow detection
  93. GRB 240619A: Swift ToO observations
  94. Fermi GBM Sub-Threshold Detection of GRB 240619C
  95. GRB 240619A: GOTO candidate optical afterglow
  96. EP240618a: Abastumani optical observationsEP240618a
  97. GRB 240615A: NOT optical observations
  98. EP240618a: GRANDMA Optical Upper Limits
  99. EP240618a: TRT optical upper limit
  100. Fermi trigger No 740474239: Global MASTER-Net observations report

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