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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"

32509 results found.

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

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