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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"

28274 results found.

  1. EP241217A: LCO optical observations
  2. EP241217a: Gemini-North detection of the likely optical counterpart
  3. EP241217a: EP detection of an X-ray transient
  4. EP241107a: VLA Radio Observation
  5. GRB 241213A: Swift-BAT refined analysis
  6. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  7. GRB 241215A: Mondy AZT-33IK optical observations
  8. GRB 241212A: Swift-XRT observations
  9. GRB 241215A: Nanshan/HMT optical upper limit
  10. GRB 241215A: Montarrenti Observatory optical upper limit
  11. GRB 241215A: GROWTH-India telescope optical upper limit
  12. GRB 241215A: A long GRB detected by INTEGRAL
  13. Integral GRB241215.58: Global MASTER-Net observations report
  14. GRB 241213B: Swift-XRT observations
  15. GRB 241213A: Swift/UVOT Upper Limits
  16. GRB 241213A: Swift-XRT refined Analysis
  17. GRB 241212A: Fermi GBM detection
  18. EP241208a: NOT optical upper limits
  19. GRB 241213A: LCOGT Optical Upper Limits
  20. GRB 241213B: MAXI/GSC detection
  21. EP241213a: EP detection of An X-ray Transient
  22. GRB 241213A: REM optical/NIR upper limits
  23. GRB 241213A: Enhanced Swift-XRT position
  24. GRB241212A: OHP/T193 optical observations
  25. GRB 241213A: SAO RAS optical upper limit
  26. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  27. GRB 241213A: Swift detection of a burst
  28. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  29. GRB 241212A: AstroSat CZTI detection
  30. GRB 241209B: GRANDMA/TRT upper limit
  31. GRB 241207A: TSHAO Zeiss-1000 optical observations
  32. GRB 241212A: SVOM detection of a bright long burst
  33. GRB 241207A: EIRSAT-1 GMOD Detection
  34. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  36. GRB 241129A: Fermi GBM Observation
  37. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  38. GRB 241209D: REM optical/NIR upper limits
  39. GRB 241209B: Swift-XRT afterglow detection
  40. GRB 241209C: Fermi GBM Observation
  41. GRB 241209A: Swift-XRT refined Analysis
  42. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  43. EP241208a: Optical upper limit with Kinder observations
  44. GRB 241209B: SVOM/VT afterglow detection
  45. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  47. GRB 241207B: Fermi GBM Observation
  48. GRB 241209D: Swift-XRT refined Analysis
  49. GRB 241209D: Fermi GBM Observation
  50. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  51. GRB 241209D: COLIBRÍ detection of the afterglow
  52. GRB 241209A: COLIBRÍ Optical Upper Limit
  53. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  54. GRB 241209A: GRANDMA/TAROT upper limit
  55. GRB 241209A: REM optical/NIR observations
  56. GRB 241209D: Enhanced Swift-XRT position
  57. GRB 241209D: Swift detection of a burst
  58. GRB 241209A: Enhanced Swift-XRT position
  59. GRB 241114B: cubesat Avion detection
  60. GRB 241209A: VLT optical observations
  61. GRB 241209A: GOTO optical upper limits
  62. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  63. EP241208a: EP detection of a fast X-ray transient
  64. GRB 241209A: Swift detection of a short burst
  65. Fermi GRB 241207B: Global MASTER-Net observations report
  66. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  67. GRB 241206A: DDOTI Upper Limit on the Afterglow
  68. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  69. GRB 241207C: MAXI/GSC detection
  70. EP241206a: EP detection of a fast X-ray transient
  71. GRB 241206A: Fermi GBM observation
  72. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  73. EP241201a: 1.6m Mephisto Optical Upper Limits
  74. GRB 241204A: COLIBRÍ Optical Upper Limit
  75. EP241202b: KAIT optical upper limit
  76. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  77. GRB 241204A: DDOTI Upper Limits on the Afterglow
  78. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  79. GRB 241128A : RAPAS follow-up observations
  80. EP241202b: Upper limits from Fermi-GBM Observations
  81. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  82. EP241202b: Kinder optical counterpart candidate
  83. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  84. GRB 241113B : RAPAS follow-up observation
  85. Konus-Wind detection of GRB 241130A
  86. EP241201a: BOOTES-5 optical upper limit
  87. EP241202b: EP detection of a fast X-ray transient
  88. EP241201a: NOT optical observations
  89. IPN triangulation of GRB 241130A
  90. GRB 241130A: EIRSAT-1 GMOD Detection
  91. GRB 241128A: Swift/UVOT Upper Limits
  92. GRB 241130A: Fermi GBM Detection
  93. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  94. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  95. EP241201a: Kinder optical counterpart candidate
  96. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  97. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  98. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  99. EP241126a: 1.6m Mephisto Optical Upper Limits
  100. GRB 241201A: Fermi GBM Final Real-time Localization

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