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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"

32494 results found.

  1. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  2. Fermi GRB 240821B: Global MASTER-Net observations report
  3. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  4. GRB 240821A: SVOM/GRM observation
  5. GRB 240821A: SVOM/GRM observation
  6. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  7. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  8. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  9. GRB 240819A: Swift-XRT observations
  10. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  11. EP240820a: TRT optical upper limit
  12. GRB 240819A: KAIT optical upper limit
  13. EP240816a: PRIME upper limits
  14. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  15. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  16. GRB 240819A: Swift ToO observations
  17. GRB 240814A: SVOM/GRM observation
  18. EP240816b: Liverpool Telescope optical follow-up observations
  19. GRB 240814C: SVOM/GRM observation
  20. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  21. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  22. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  23. EP240816b: KAIT optical upper limit
  24. GRB 240814B: GRBAlpha detection
  25. EP EP240816b: Global MASTER-Net observations report
  26. EP240816b: TRT optical upper limit
  27. Fermi GRB 240814A: Global MASTER-Net observations report
  28. Fermi GRB 240814C: Global MASTER-Net observations report
  29. Fermi GRB 240814B: Global MASTER-Net observations report
  30. GRB 240812B: SVOM/GRM observation
  31. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  32. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  33. Konus-Wind detection of GRB 240811A
  34. Konus-Wind detection of GRB 240810A
  35. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  36. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  37. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  38. GRB 240809A: Correction to the VLA source position in GCN 37158
  39. GRB 240810A: SVOM/GRM observation
  40. GRB 240809A: ATA radio non-detection
  41. GRB 240809A : RAPAS follow-up observations
  42. GRB 240809A: VLA detection
  43. GRB 240809A: ALMA detection
  44. IPN triangulation of GRB 240810A (short)
  45. GRB 240811A: Swift-BAT refined analysis
  46. GRB 240809A: Swift-BAT refined analysis
  47. EP240807a: PRIME H-band upper limits
  48. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube
  49. GRB 240811A: Bassano Bresciano Observatory upper limit
  50. GRB 240811A: Swift/UVOT Upper Limits
  51. EP240801a: Assy-Turgen optical observations
  52. Fermi GRB 240810A: Global MASTER-Net observations report
  53. GRB 240811A: LCOGT Optical Upper Limit
  54. GRB 240811A: Upper limits with Mephisto
  55. Konus-Wind detection of GRB 240809A
  56. Swift GRB 240811A: Global MASTER-Net observations report
  57. GRB240809A: Liverpool Telescope optical follow-up observations
  58. GRB 240809A: REM detection of the optical afterglow
  59. GRB 240809A: Bassano Bresciano Observatory optical observations
  60. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  61. GRB 240809A: Conclusive redshift from VLT
  62. Fermi-LAT gamma-ray observations of IceCube-240808A
  63. GRB 240809A: KAIT optical observations
  64. GRB 240808A: AstroSat CZTI detection
  65. GRB 240809A: GIT afterglow observations
  66. GRB 240809A: Swift/UVOT Detection
  67. GRB 240809A: Tentative redshift from NOT
  68. IPN triangulation of GRB 240807A / EP 240807a
  69. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  70. X-ray Transient EP240807a: PRIME near-infrared upper limits
  71. Swift GRB 240809A: Global MASTER-Net observations report
  72. GRB 240809A: JinShan optical observations
  73. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  74. GRB 240809A: SVOM/GRM observation
  75. GRB 240807A: SVOM/GRM observation
  76. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  77. EP240807a: STEP/T80S optical limits
  78. GRB 240807B: AstroSat CZTI detection of a short burst
  79. EP EP240807a: Global MASTER-Net observations report
  80. EP EP240806a: Global MASTER-Net observations report
  81. GRB 240801A: GRBAlpha detection
  82. GRB 240710B: VZLUSAT-2 detection
  83. GRB 240805A: ATCA Radio Upper Limits
  84. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  85. S240807h: Identification of a GW compact binary merger candidate
  86. EP240802a/GRB240802A: KAIT optical upper limit
  87. GRB 240720B: VZLUSAT-2 detection
  88. GRB 240710A: VZLUSAT-2 detection
  89. EP240806A: Liverpool Telescope optical follow-up observations
  90. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  91. GRB 240805B: GIT optical upper limit
  92. EP240806a: KAIT optical observations
  93. GRB 240805B: Swift-BAT refined analysis
  94. GRB 240805A: Swift-BAT refined analysis
  95. EP240804a (GRB 240804B): NOT optical observations
  96. EP240806a: LCOGT optical counterpart detection
  97. Konus-Wind detection of GRB 240802A (EP240802a)
  98. Improved IPN triangulation of GRB 240802A / EP 240802a
  99. Konus-Wind detection of GRB 240805A
  100. GRB 240805B Bassano Bresciano Observatory upper limit

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