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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"

32716 results found.

  1. GRB 240824A: Retraction of GCN 37255
  2. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  3. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  4. GRB 240824A: KAIT optical upper limit
  5. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  6. GRB 240821A: Colibri Optical Upper Limit
  7. EP240820a: PRIME J-band Observations
  8. GRB 240821A: Swift-XRT observations
  9. GRB 240821A: REM optical/NIR upper limits
  10. GRB 240821A: LCO optical observations
  11. GRB 240821A: JinShan optical upper limits
  12. GRB 240809A: Mondy and AbAO Optical Observations
  13. GRB 240821A: SVOM/VT follow-up and optical upper limit
  14. GRB 240821A: GMG Optical Upper Limit
  15. Fermi GRB 240821A: Global MASTER-Net observations report
  16. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  17. GRB 240821A: Fermi GBM Observation
  18. GRB 240821A: Swift ToO observations
  19. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  20. GRB240821A: EIRSAT-1 GMOD Detection
  21. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  22. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  23. Fermi GRB 240821B: Global MASTER-Net observations report
  24. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  25. GRB 240821A: SVOM/GRM observation
  26. GRB 240821A: SVOM/GRM observation
  27. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  28. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  29. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  30. GRB 240819A: Swift-XRT observations
  31. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  32. EP240820a: TRT optical upper limit
  33. GRB 240819A: KAIT optical upper limit
  34. EP240816a: PRIME upper limits
  35. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  36. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  37. GRB 240819A: Swift ToO observations
  38. GRB 240814A: SVOM/GRM observation
  39. EP240816b: Liverpool Telescope optical follow-up observations
  40. GRB 240814C: SVOM/GRM observation
  41. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  42. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  43. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  44. EP240816b: KAIT optical upper limit
  45. GRB 240814B: GRBAlpha detection
  46. EP EP240816b: Global MASTER-Net observations report
  47. EP240816b: TRT optical upper limit
  48. Fermi GRB 240814A: Global MASTER-Net observations report
  49. Fermi GRB 240814C: Global MASTER-Net observations report
  50. Fermi GRB 240814B: Global MASTER-Net observations report
  51. GRB 240812B: SVOM/GRM observation
  52. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  53. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  54. Konus-Wind detection of GRB 240811A
  55. Konus-Wind detection of GRB 240810A
  56. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  58. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  59. GRB 240809A: Correction to the VLA source position in GCN 37158
  60. GRB 240810A: SVOM/GRM observation
  61. GRB 240809A: ATA radio non-detection
  62. GRB 240809A : RAPAS follow-up observations
  63. GRB 240809A: VLA detection
  64. GRB 240809A: ALMA detection
  65. IPN triangulation of GRB 240810A (short)
  66. GRB 240811A: Swift-BAT refined analysis
  67. GRB 240809A: Swift-BAT refined analysis
  68. EP240807a: PRIME H-band upper limits
  69. IceCube-240808A: Upper limits from a search for additional neutrino events in IceCube
  70. GRB 240811A: Bassano Bresciano Observatory upper limit
  71. GRB 240811A: Swift/UVOT Upper Limits
  72. EP240801a: Assy-Turgen optical observations
  73. Fermi GRB 240810A: Global MASTER-Net observations report
  74. GRB 240811A: LCOGT Optical Upper Limit
  75. GRB 240811A: Upper limits with Mephisto
  76. Konus-Wind detection of GRB 240809A
  77. Swift GRB 240811A: Global MASTER-Net observations report
  78. GRB240809A: Liverpool Telescope optical follow-up observations
  79. GRB 240809A: REM detection of the optical afterglow
  80. GRB 240809A: Bassano Bresciano Observatory optical observations
  81. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  82. GRB 240809A: Conclusive redshift from VLT
  83. Fermi-LAT gamma-ray observations of IceCube-240808A
  84. GRB 240809A: KAIT optical observations
  85. GRB 240808A: AstroSat CZTI detection
  86. GRB 240809A: GIT afterglow observations
  87. GRB 240809A: Swift/UVOT Detection
  88. GRB 240809A: Tentative redshift from NOT
  89. IPN triangulation of GRB 240807A / EP 240807a
  90. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  91. X-ray Transient EP240807a: PRIME near-infrared upper limits
  92. Swift GRB 240809A: Global MASTER-Net observations report
  93. GRB 240809A: JinShan optical observations
  94. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  95. GRB 240809A: SVOM/GRM observation
  96. GRB 240807A: SVOM/GRM observation
  97. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  98. EP240807a: STEP/T80S optical limits
  99. GRB 240807B: AstroSat CZTI detection of a short burst
  100. EP EP240807a: Global MASTER-Net observations report

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