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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"

28261 results found.

  1. GRB 241213B: Swift-XRT observations
  2. GRB 241213A: Swift/UVOT Upper Limits
  3. GRB 241213A: Swift-XRT refined Analysis
  4. GRB 241212A: Fermi GBM detection
  5. EP241208a: NOT optical upper limits
  6. GRB 241213A: LCOGT Optical Upper Limits
  7. GRB 241213B: MAXI/GSC detection
  8. EP241213a: EP detection of An X-ray Transient
  9. GRB 241213A: REM optical/NIR upper limits
  10. GRB 241213A: Enhanced Swift-XRT position
  11. GRB241212A: OHP/T193 optical observations
  12. GRB 241213A: SAO RAS optical upper limit
  13. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  14. GRB 241213A: Swift detection of a burst
  15. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  16. GRB 241212A: AstroSat CZTI detection
  17. GRB 241209B: GRANDMA/TRT upper limit
  18. GRB 241207A: TSHAO Zeiss-1000 optical observations
  19. GRB 241212A: SVOM detection of a bright long burst
  20. GRB 241207A: EIRSAT-1 GMOD Detection
  21. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  22. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  23. GRB 241129A: Fermi GBM Observation
  24. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  25. GRB 241209D: REM optical/NIR upper limits
  26. GRB 241209B: Swift-XRT afterglow detection
  27. GRB 241209C: Fermi GBM Observation
  28. GRB 241209A: Swift-XRT refined Analysis
  29. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  30. EP241208a: Optical upper limit with Kinder observations
  31. GRB 241209B: SVOM/VT afterglow detection
  32. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  33. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  34. GRB 241207B: Fermi GBM Observation
  35. GRB 241209D: Swift-XRT refined Analysis
  36. GRB 241209D: Fermi GBM Observation
  37. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  38. GRB 241209D: COLIBRÍ detection of the afterglow
  39. GRB 241209A: COLIBRÍ Optical Upper Limit
  40. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  41. GRB 241209A: GRANDMA/TAROT upper limit
  42. GRB 241209A: REM optical/NIR observations
  43. GRB 241209D: Enhanced Swift-XRT position
  44. GRB 241209D: Swift detection of a burst
  45. GRB 241209A: Enhanced Swift-XRT position
  46. GRB 241114B: cubesat Avion detection
  47. GRB 241209A: VLT optical observations
  48. GRB 241209A: GOTO optical upper limits
  49. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  50. EP241208a: EP detection of a fast X-ray transient
  51. GRB 241209A: Swift detection of a short burst
  52. Fermi GRB 241207B: Global MASTER-Net observations report
  53. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  54. GRB 241206A: DDOTI Upper Limit on the Afterglow
  55. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  56. GRB 241207C: MAXI/GSC detection
  57. EP241206a: EP detection of a fast X-ray transient
  58. GRB 241206A: Fermi GBM observation
  59. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  60. EP241201a: 1.6m Mephisto Optical Upper Limits
  61. GRB 241204A: COLIBRÍ Optical Upper Limit
  62. EP241202b: KAIT optical upper limit
  63. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  64. GRB 241204A: DDOTI Upper Limits on the Afterglow
  65. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  66. GRB 241128A : RAPAS follow-up observations
  67. EP241202b: Upper limits from Fermi-GBM Observations
  68. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  69. EP241202b: Kinder optical counterpart candidate
  70. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  71. GRB 241113B : RAPAS follow-up observation
  72. Konus-Wind detection of GRB 241130A
  73. EP241201a: BOOTES-5 optical upper limit
  74. EP241202b: EP detection of a fast X-ray transient
  75. EP241201a: NOT optical observations
  76. IPN triangulation of GRB 241130A
  77. GRB 241130A: EIRSAT-1 GMOD Detection
  78. GRB 241128A: Swift/UVOT Upper Limits
  79. GRB 241130A: Fermi GBM Detection
  80. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  81. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  82. EP241201a: Kinder optical counterpart candidate
  83. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  84. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  85. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  86. EP241126a: 1.6m Mephisto Optical Upper Limits
  87. GRB 241201A: Fermi GBM Final Real-time Localization
  88. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  89. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  90. Fermi trigger No 754701230: Global MASTER-Net observations report
  91. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  92. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  93. GRB 241128A: AbAO optical upper limit
  94. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  95. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  96. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  97. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  98. GRB 241128A: Swift-BAT refined analysis
  99. GRB 241127A: Swift-BAT refined analysis
  100. GRB 241127A: PRIME near-infrared detection

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