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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

22060 results found.

  1. Fermi trigger No 745871958: Global MASTER-Net observations report
  2. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  3. GRB 240819A: Swift ToO observations
  4. EP240816b: Liverpool Telescope optical follow-up observations
  5. Integral GRB240816.79: Global MASTER-Net observations report
  6. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  7. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  8. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  9. Fermi trigger No 745501396: Global MASTER-Net observations report
  10. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  11. EP EP240816b: Global MASTER-Net observations report
  12. EP240816b: TRT optical upper limit
  13. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  14. Fermi GRB 240814A: Global MASTER-Net observations report
  15. Fermi GRB 240814C: Global MASTER-Net observations report
  16. Fermi trigger No 745306088: Global MASTER-Net observations report
  17. Fermi GRB 240814B: Global MASTER-Net observations report
  18. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  19. Fermi trigger No 745220784: Global MASTER-Net observations report
  20. Konus-Wind detection of GRB 240810A
  21. GRB 240809A: ATA radio non-detection
  22. GRB 240809A : RAPAS follow-up observations
  23. GRB 240809A: VLA detection
  24. GRB 240809A: ALMA detection
  25. EP240807a: PRIME H-band upper limits
  26. GRB 240811A: Bassano Bresciano Observatory upper limit
  27. GRB 240811A: Swift/UVOT Upper Limits
  28. EP240801a: Assy-Turgen optical observations
  29. Fermi GRB 240810A: Global MASTER-Net observations report
  30. GRB 240811A: Upper limits with Mephisto
  31. Konus-Wind detection of GRB 240809A
  32. Fermi trigger No 745057312: Global MASTER-Net observations report
  33. Swift GRB 240811A: Global MASTER-Net observations report
  34. GRB240809A: Liverpool Telescope optical follow-up observations
  35. GRB 240809A: REM detection of the optical afterglow
  36. GRB 240809A: Bassano Bresciano Observatory optical observations
  37. Fermi-LAT gamma-ray observations of IceCube-240808A
  38. GRB 240809A: KAIT optical observations
  39. GRB 240809A: GIT afterglow observations
  40. GRB 240809A: Swift/UVOT Detection
  41. GRB 240809A: Tentative redshift from NOT
  42. X-ray Transient EP240807a: PRIME near-infrared upper limits
  43. Swift GRB 240809A: Global MASTER-Net observations report
  44. GRB 240809A: JinShan optical observations
  45. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  46. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  47. EP240807a: STEP/T80S optical limits
  48. IceCube Alert 240808.27: Global MASTER-Net observations report
  49. EP EP240807a: Global MASTER-Net observations report
  50. EP EP240806a: Global MASTER-Net observations report
  51. GRB 240805A: ATCA Radio Upper Limits
  52. Fermi trigger No 744761058: Global MASTER-Net observations report
  53. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  54. EP240806A: Liverpool Telescope optical follow-up observations
  55. EP240807a: EP-WXT detection of a fast X-ray transient
  56. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  57. GRB 240805B: GIT optical upper limit
  58. EP240806a: KAIT optical observations
  59. Fermi trigger No 744629911: Global MASTER-Net observations report
  60. EP240804a (GRB 240804B): NOT optical observations
  61. EP240806a: LCOGT optical counterpart detection
  62. Konus-Wind detection of GRB 240802A (EP240802a)
  63. Konus-Wind detection of GRB 240805A
  64. GRB 240805B Bassano Bresciano Observatory upper limit
  65. GRB 240805B: JinShan optical afterglow detection
  66. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  67. EP 240806A: LCO optical observations
  68. EP240806a: GSP optical counterpart detection
  69. EP240806a: EP-WXT detection of a fast X-ray transient
  70. GRB 240805B: Optical detection with 1.6m Mephisto
  71. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  72. Fermi trigger No 744544656: Global MASTER-Net observations report
  73. GRB 240805B: Swift/UVOT Upper Limits
  74. GRB 240805A: Swift/UVOT Upper Limits
  75. GRB 240805B: BTA optical afterglow candidate
  76. Swift GRB 240805B: Global MASTER-Net observations report
  77. GRB 240805B: JinShan optical upper limits
  78. Fermi GRB 240805A: Global MASTER-Net observations report
  79. Swift GRB 240805A: Global MASTER-Net observations report
  80. EP240804a: GSP detects optical candidate counterpart
  81. EP240801a: Continued optical observations at ZTSh (CraO)
  82. EP240804a: VLT/X-shooter spectroscopic redshift
  83. EP240804a: LCOGT optical counterpart detection
  84. EP240804a: NOT optical counterpart detection
  85. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  86. GRB 240805A: Swift detection of a burst
  87. Fermi GRB 240804A: Global MASTER-Net observations report
  88. EP240802a: Montarrenti Observatory optical upper limit
  89. Fermi trigger No 744459130: Global MASTER-Net observations report
  90. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  91. EP240802A: Bassano Bresciano Observatory upper limit
  92. GRB 240802A: SVOM/GRM observation
  93. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  94. Fermi trigger No 744278264: Global MASTER-Net observations report
  95. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  96. EP240801a: further SAO RAS optical observations
  97. EP240801a: optical observations at CrAO and AbAO
  98. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  99. EP240801a: Leavitt Observatory optical observations
  100. EP240801a: GTC spectroscopy and absorption redshift

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