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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').
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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"

43127 results found.

  1. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  2. EP241208a: Optical upper limit with Kinder observations
  3. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  4. GRB 241209D: AstroSat CZTI detection
  5. GRB 241209A: EP-FXT follow-up observations
  6. GRB 241209B: SVOM/VT afterglow detection
  7. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  8. EP241208a: Global MASTER-Net observations report
  9. EP241208a: EP-FXT follow-up observations
  10. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  11. Fermi trigger No 755485387: Global MASTER-Net observations report
  12. GRB 241207B: Fermi GBM Observation
  13. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  14. GRB 241209D: Swift-XRT refined Analysis
  15. GRB 241209D: Fermi GBM Observation
  16. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  17. GRB 241209D: COLIBRÍ detection of the afterglow
  18. GRB 241209A: COLIBRÍ Optical Upper Limit
  19. Fermi GRB 241209D: Global MASTER-Net observations report
  20. GRB 241209A: Fermi GBM Observation
  21. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  22. GRB 241209A: GRANDMA/TAROT upper limit
  23. GRB 241209B: BOOTES-5 optical upper limit
  24. Swift GRB 241209D: Global MASTER-Net observations report
  25. Fermi GRB 241209C: Global MASTER-Net observations report
  26. Fermi GRB 241209E: Global MASTER-Net observations report
  27. GRB 241209E: Fermi GBM Final Real-time Localization
  28. GRB 241209B: Swift ToO observations
  29. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  30. GRB 241209A: REM optical/NIR observations
  31. GRB 241209D: Enhanced Swift-XRT position
  32. GRB 241209C: AstroSat CZTI detection
  33. GRB 241209D: Swift detection of a burst
  34. GRB 241209D: Fermi GBM Final Real-time Localization
  35. GRB 241209A: VLT/X-shooter spectroscopy
  36. GRB 241209A: Enhanced Swift-XRT position
  37. GRB 241114B: cubesat Avion detection
  38. GRB 241209A: VLT optical observations
  39. Fermi GRB 241209A: Global MASTER-Net observations report
  40. GRB 241209C: Fermi GBM Final Real-time Localization
  41. GRB 241209A: GOTO optical upper limits
  42. EP241206a: 1.5m OSN optical limit
  43. GRB 241209A: Prompt enhanced Swift-XRT position
  44. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  45. EP241208a: EP detection of a fast X-ray transient
  46. GRB 241209A: Swift detection of a short burst
  47. Swift GRB241209.23: Global MASTER-Net observations report
  48. GRB 241209A: Fermi GBM Final Real-time Localization
  49. Fermi GRB 241207B: Global MASTER-Net observations report
  50. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  51. GRB 241201A: AstroSat CZTI detection
  52. GRB 241206A: DDOTI Upper Limit on the Afterglow
  53. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  54. EP241206a: BOOTES Global Network optical limits
  55. GRB 241207C: MASTER optical observations
  56. Fermi trigger No 755225799: Global MASTER-Net observations report
  57. GRB 241207C: Tiled Swift observations
  58. GRB 241207C: MAXI/GSC detection
  59. GRB 241207B: Fermi GBM Final Real-time Localization
  60. Fermi trigger No 755277791: Global MASTER-Net observations report
  61. Fermi GRB 241207A: Global MASTER-Net observations report
  62. EP241206a: Global MASTER-Net observations report
  63. EP241206a: EP detection of a fast X-ray transient
  64. GRB 241206A: Fermi GBM observation
  65. GRB 241206C: SVOM/GRM observation of a likely short burst
  66. GRB 241207A: Fermi GBM Final Real-time Localization
  67. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  68. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  69. GRB 241206B: GWAC-F50A optical upper limit
  70. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  71. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  72. Fermi GRB 241206A: Global MASTER-Net observations report
  73. GRB 241206A: Fermi GBM Final Real-time Localization
  74. EP241201a: 1.6m Mephisto Optical Upper Limits
  75. GRB 241204A: COLIBRÍ Optical Upper Limit
  76. EP241202b: KAIT optical upper limit
  77. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  78. GRB 241204A: DDOTI Upper Limits on the Afterglow
  79. GRB 241204A: Fermi GBM Observation
  80. Fermi GRB 241204A: Global MASTER-Net observations report
  81. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241201A: GRBAlpha detection
  83. GRB 241204A: Fermi-LAT detection
  84. EP241202b: Upper limits from Fermi-GBM Observations
  85. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  86. EP241202b: Kinder optical counterpart candidate
  87. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  88. EP241201a: EP-FXT follow-up observations
  89. Konus-Wind detection of GRB 241130A
  90. EP241202b: Global MASTER-Net observations report
  91. EP241201a: BOOTES-5 optical upper limit
  92. EP241202b: EP detection of a fast X-ray transient
  93. EP241201a: NOT optical observations
  94. IPN triangulation of GRB 241130A
  95. GRB 241130A: EIRSAT-1 GMOD Detection
  96. GRB 241128A: Swift/UVOT Upper Limits
  97. GRB 241130A: Fermi GBM Detection
  98. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  99. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  100. EP241201a: Kinder optical counterpart candidate

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