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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"

21980 results found.

  1. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  2. GRB 240825A: KAIT optical observations
  3. GRB 240825A: PRIME near-infrared detection
  4. GRB 240825A: AKO Optical Follow-Up Observations
  5. GRB 240825A: Swift/UVOT Detection
  6. GRB 240825A: REM detection of the optical/NIR afterglow
  7. GRB 240825A: VLT/X-shooter redshift
  8. GRB 240825A: SVOM/C-GFT optical observations
  9. GRB 240825A: Montarrenti Observatory optical observations
  10. GRB 240825A: MASTER optical counterpart observation
  11. GRB 240825A: LCO optical observations
  12. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  13. Fermi GRB 240825A: Global MASTER-Net observations report
  14. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  15. GRB 240824B: NOT optical upper limit
  16. Swift GRB 240825A: Global MASTER-Net observations report
  17. GRB 240825A: 1.6m Mephisto multi-band detection
  18. GRB 240825A: Skynet Optical Afterglow observations
  19. GRB 240825A: Nanshan/HMT optical afterglow observations
  20. GRB 240824B: Swift-XRT afterglow detection
  21. GRB 240824A: Swift-XRT observations
  22. GRB 240824B: Swift/BAT arcminute localization of a burst
  23. GRB 240824B: Swift ToO observations
  24. Fermi GRB 240824C: Global MASTER-Net observations report
  25. GRB 240824A: Swift/UVOT Upper Limits
  26. GRB 240821A: Swift/UVOT observations of the XRT sources.
  27. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  28. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  29. GRB 240824A: KAIT optical upper limit
  30. GRB 240824A: Skynet Optical Afterglow Discovery
  31. Swift GRB240824.04: Global MASTER-Net observations report
  32. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  33. GRB 240821A: Colibri Optical Upper Limit
  34. EP240820a: PRIME J-band Observations
  35. GRB 240821A: Swift-XRT observations
  36. GRB 240821A: REM optical/NIR upper limits
  37. GRB 240821A: LCO optical observations
  38. GRB 240821A: JinShan optical upper limits
  39. GRB 240809A: Mondy and AbAO Optical Observations
  40. GRB 240821A: SVOM/VT follow-up and optical upper limit
  41. Fermi GRB 240821A: Global MASTER-Net observations report
  42. Fermi trigger No 745964969: Global MASTER-Net observations report
  43. Fermi trigger No 745925274: Global MASTER-Net observations report
  44. GRB 240821A: Swift ToO observations
  45. Fermi trigger No 746019401: Global MASTER-Net observations report
  46. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  47. Fermi trigger No 745935375: Global MASTER-Net observations report
  48. Fermi GRB 240821B: Global MASTER-Net observations report
  49. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  50. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  51. Fermi trigger No 745866488: Global MASTER-Net observations report
  52. GRB 240819A: Swift-XRT observations
  53. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  54. EP240820a: TRT optical upper limit
  55. EP240820a: EP detection of a fast X-ray transient
  56. GRB 240819A: KAIT optical upper limit
  57. EP240816a: PRIME upper limits
  58. Fermi trigger No 745873283: Global MASTER-Net observations report
  59. Fermi trigger No 745871958: Global MASTER-Net observations report
  60. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  61. GRB 240819A: Swift ToO observations
  62. EP240816b: Liverpool Telescope optical follow-up observations
  63. Integral GRB240816.79: Global MASTER-Net observations report
  64. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  65. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  66. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  67. Fermi trigger No 745501396: Global MASTER-Net observations report
  68. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  69. EP EP240816b: Global MASTER-Net observations report
  70. EP240816b: TRT optical upper limit
  71. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  72. Fermi GRB 240814A: Global MASTER-Net observations report
  73. Fermi GRB 240814C: Global MASTER-Net observations report
  74. Fermi trigger No 745306088: Global MASTER-Net observations report
  75. Fermi GRB 240814B: Global MASTER-Net observations report
  76. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  77. Fermi trigger No 745220784: Global MASTER-Net observations report
  78. GRB 240809A: ATA radio non-detection
  79. GRB 240809A : RAPAS follow-up observations
  80. GRB 240809A: VLA detection
  81. GRB 240809A: ALMA detection
  82. EP240807a: PRIME H-band upper limits
  83. GRB 240811A: Bassano Bresciano Observatory upper limit
  84. GRB 240811A: Swift/UVOT Upper Limits
  85. EP240801a: Assy-Turgen optical observations
  86. Fermi GRB 240810A: Global MASTER-Net observations report
  87. GRB 240811A: Upper limits with Mephisto
  88. Fermi trigger No 745057312: Global MASTER-Net observations report
  89. Swift GRB 240811A: Global MASTER-Net observations report
  90. GRB240809A: Liverpool Telescope optical follow-up observations
  91. GRB 240809A: REM detection of the optical afterglow
  92. GRB 240809A: Bassano Bresciano Observatory optical observations
  93. GRB 240809A: Conclusive redshift from VLT
  94. Fermi-LAT gamma-ray observations of IceCube-240808A
  95. GRB 240809A: KAIT optical observations
  96. GRB 240809A: GIT afterglow observations
  97. GRB 240809A: Swift/UVOT Detection
  98. GRB 240809A: Tentative redshift from NOT
  99. X-ray Transient EP240807a: PRIME near-infrared upper limits
  100. Swift GRB 240809A: Global MASTER-Net observations report

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