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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"

32752 results found.

  1. Konus-Wind detection of GRB 240825A (bright/long)
  2. GRB 240825A: Fermi GBM Observation
  3. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  4. GRB 240825A: AKO Optical Follow-Up Observations
  5. GRB 240825A: AstroSat CZTI detection of the long bright burst
  6. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  7. GRB 240825A: Swift/UVOT Detection
  8. GRB 240825A: REM detection of the optical/NIR afterglow
  9. GRB 240825A: VLT/X-shooter redshift
  10. GRB 240825A: SVOM/C-GFT optical observations
  11. GRB 240825A: Montarrenti Observatory optical observations
  12. GRB 240825A: MASTER optical counterpart observation
  13. GRB 240825A: Fermi-LAT detection
  14. GRB 240825A: LCO optical observations
  15. GRB 240824B: KAIT optical upper limit
  16. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  17. GRB 240824B: Fermi GBM Observation
  18. Fermi GRB 240825A: Global MASTER-Net observations report
  19. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  20. GRB 240824B: NOT optical upper limit
  21. GRB 240825A: GMG Optical Observation
  22. Swift GRB 240825A: Global MASTER-Net observations report
  23. GRB 240825A: 1.6m Mephisto multi-band detection
  24. GRB 240825A: AKO Optical Afterglow Detection
  25. GRB 240825A: Skynet Optical Afterglow observations
  26. GRB 240825A: Nanshan/HMT optical afterglow observations
  27. GRB 240824A: Swift-BAT refined analysis
  28. GRB 240824A: SVOM/C-GFT optical upper limit
  29. GRB 240824B: Swift-XRT afterglow detection
  30. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  31. GRB 240824B: Swift/BAT arcminute localization of a burst
  32. GRB 240824B: Swift ToO observations
  33. Fermi GRB 240824C: Global MASTER-Net observations report
  34. GRB 240824A: Swift/UVOT Upper Limits
  35. GRB 240821A: Swift/UVOT observations of the XRT sources.
  36. GRB 240824B: MAXI/GSC detection
  37. GRB 240824A: Retraction of GCN 37255
  38. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  39. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  40. GRB 240824A: KAIT optical upper limit
  41. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  42. GRB 240821A: Colibri Optical Upper Limit
  43. EP240820a: PRIME J-band Observations
  44. GRB 240821A: Swift-XRT observations
  45. GRB 240821A: REM optical/NIR upper limits
  46. GRB 240821A: LCO optical observations
  47. GRB 240821A: JinShan optical upper limits
  48. GRB 240809A: Mondy and AbAO Optical Observations
  49. GRB 240821A: SVOM/VT follow-up and optical upper limit
  50. GRB 240821A: GMG Optical Upper Limit
  51. Fermi GRB 240821A: Global MASTER-Net observations report
  52. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  53. GRB 240821A: Fermi GBM Observation
  54. GRB 240821A: Swift ToO observations
  55. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  56. GRB240821A: EIRSAT-1 GMOD Detection
  57. GRB240821B: First GRB Detected by EIRSAT-1 GMOD
  58. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  59. Fermi GRB 240821B: Global MASTER-Net observations report
  60. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  61. GRB 240821A: SVOM/GRM observation
  62. GRB 240821A: SVOM/GRM observation
  63. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  64. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  65. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  66. GRB 240819A: Swift-XRT observations
  67. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  68. EP240820a: TRT optical upper limit
  69. GRB 240819A: KAIT optical upper limit
  70. EP240816a: PRIME upper limits
  71. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  72. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  73. GRB 240819A: Swift ToO observations
  74. GRB 240814A: SVOM/GRM observation
  75. EP240816b: Liverpool Telescope optical follow-up observations
  76. GRB 240814C: SVOM/GRM observation
  77. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  78. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  79. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  80. EP240816b: KAIT optical upper limit
  81. GRB 240814B: GRBAlpha detection
  82. EP EP240816b: Global MASTER-Net observations report
  83. EP240816b: TRT optical upper limit
  84. Fermi GRB 240814A: Global MASTER-Net observations report
  85. Fermi GRB 240814C: Global MASTER-Net observations report
  86. Fermi GRB 240814B: Global MASTER-Net observations report
  87. GRB 240812B: SVOM/GRM observation
  88. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  89. LIGO/Virgo/KAGRA S240813d: Updated Sky localization
  90. Konus-Wind detection of GRB 240811A
  91. Konus-Wind detection of GRB 240810A
  92. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S240813c: Updated Sky localization
  94. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  95. GRB 240809A: Correction to the VLA source position in GCN 37158
  96. GRB 240810A: SVOM/GRM observation
  97. GRB 240809A: ATA radio non-detection
  98. GRB 240809A : RAPAS follow-up observations
  99. GRB 240809A: VLA detection
  100. GRB 240809A: ALMA detection

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