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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"

32501 results found.

  1. Fermi GRB 240821A: Global MASTER-Net observations report
  2. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  3. GRB 240821A: Fermi GBM Observation
  4. GRB 240821A: Swift ToO observations
  5. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  6. GRB240821A: EIRSAT-1 GMOD Detection
  7. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  8. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  9. Fermi GRB 240821B: Global MASTER-Net observations report
  10. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  11. GRB 240821A: SVOM/GRM observation
  12. GRB 240821A: SVOM/GRM observation
  13. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  14. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  15. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  16. GRB 240819A: Swift-XRT observations
  17. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  18. EP240820a: TRT optical upper limit
  19. GRB 240819A: KAIT optical upper limit
  20. EP240816a: PRIME upper limits
  21. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  22. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  23. GRB 240819A: Swift ToO observations
  24. GRB 240814A: SVOM/GRM observation
  25. EP240816b: Liverpool Telescope optical follow-up observations
  26. GRB 240814C: SVOM/GRM observation
  27. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  28. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  29. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  30. EP240816b: KAIT optical upper limit
  31. GRB 240814B: GRBAlpha detection
  32. EP EP240816b: Global MASTER-Net observations report
  33. EP240816b: TRT optical upper limit
  34. Fermi GRB 240814A: Global MASTER-Net observations report
  35. Fermi GRB 240814C: Global MASTER-Net observations report
  36. Fermi GRB 240814B: Global MASTER-Net observations report
  37. GRB 240812B: SVOM/GRM observation
  38. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  39. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  40. Konus-Wind detection of GRB 240811A
  41. Konus-Wind detection of GRB 240810A
  42. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  43. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  44. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  45. GRB 240809A: Correction to the VLA source position in GCN 37158
  46. GRB 240810A: SVOM/GRM observation
  47. GRB 240809A: ATA radio non-detection
  48. GRB 240809A : RAPAS follow-up observations
  49. GRB 240809A: VLA detection
  50. GRB 240809A: ALMA detection
  51. IPN triangulation of GRB 240810A (short)
  52. GRB 240811A: Swift-BAT refined analysis
  53. GRB 240809A: Swift-BAT refined analysis
  54. EP240807a: PRIME H-band upper limits
  55. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube
  56. GRB 240811A: Bassano Bresciano Observatory upper limit
  57. GRB 240811A: Swift/UVOT Upper Limits
  58. EP240801a: Assy-Turgen optical observations
  59. Fermi GRB 240810A: Global MASTER-Net observations report
  60. GRB 240811A: LCOGT Optical Upper Limit
  61. GRB 240811A: Upper limits with Mephisto
  62. Konus-Wind detection of GRB 240809A
  63. Swift GRB 240811A: Global MASTER-Net observations report
  64. GRB240809A: Liverpool Telescope optical follow-up observations
  65. GRB 240809A: REM detection of the optical afterglow
  66. GRB 240809A: Bassano Bresciano Observatory optical observations
  67. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  68. GRB 240809A: Conclusive redshift from VLT
  69. Fermi-LAT gamma-ray observations of IceCube-240808A
  70. GRB 240809A: KAIT optical observations
  71. GRB 240808A: AstroSat CZTI detection
  72. GRB 240809A: GIT afterglow observations
  73. GRB 240809A: Swift/UVOT Detection
  74. GRB 240809A: Tentative redshift from NOT
  75. IPN triangulation of GRB 240807A / EP 240807a
  76. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  77. X-ray Transient EP240807a: PRIME near-infrared upper limits
  78. Swift GRB 240809A: Global MASTER-Net observations report
  79. GRB 240809A: JinShan optical observations
  80. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  81. GRB 240809A: SVOM/GRM observation
  82. GRB 240807A: SVOM/GRM observation
  83. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  84. EP240807a: STEP/T80S optical limits
  85. GRB 240807B: AstroSat CZTI detection of a short burst
  86. EP EP240807a: Global MASTER-Net observations report
  87. EP EP240806a: Global MASTER-Net observations report
  88. GRB 240801A: GRBAlpha detection
  89. GRB 240710B: VZLUSAT-2 detection
  90. GRB 240805A: ATCA Radio Upper Limits
  91. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  92. S240807h: Identification of a GW compact binary merger candidate
  93. EP240802a/GRB240802A: KAIT optical upper limit
  94. GRB 240720B: VZLUSAT-2 detection
  95. GRB 240710A: VZLUSAT-2 detection
  96. EP240806A: Liverpool Telescope optical follow-up observations
  97. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  98. GRB 240805B: GIT optical upper limit
  99. EP240806a: KAIT optical observations
  100. GRB 240805B: Swift-BAT refined analysis

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