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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"

43133 results found.

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

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