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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"

21981 results found.

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

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