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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"

24493 results found.

  1. Fermi GRB 241209C: Global MASTER-Net observations report
  2. Fermi GRB 241209E: Global MASTER-Net observations report
  3. GRB 241209E: Fermi GBM Final Real-time Localization
  4. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  5. GRB 241209A: REM optical/NIR observations
  6. GRB 241209D: Fermi GBM Final Real-time Localization
  7. GRB 241209A: VLT/X-shooter spectroscopy
  8. GRB 241114B: cubesat Avion detection
  9. GRB 241209A: VLT optical observations
  10. Fermi GRB 241209A: Global MASTER-Net observations report
  11. GRB 241209C: Fermi GBM Final Real-time Localization
  12. EP241206a: 1.5m OSN optical limit
  13. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  14. Swift GRB241209.23: Global MASTER-Net observations report
  15. GRB 241209A: Fermi GBM Final Real-time Localization
  16. Fermi GRB 241207B: Global MASTER-Net observations report
  17. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  18. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  19. EP241206a: BOOTES Global Network optical limits
  20. GRB 241207C: MASTER optical observations
  21. Fermi trigger No 755225799: Global MASTER-Net observations report
  22. GRB 241207B: Fermi GBM Final Real-time Localization
  23. Fermi trigger No 755277791: Global MASTER-Net observations report
  24. Fermi GRB 241207A: Global MASTER-Net observations report
  25. EP241206a: Global MASTER-Net observations report
  26. GRB 241206A: Fermi GBM observation
  27. GRB 241206C: SVOM/GRM observation of a likely short burst
  28. GRB 241207A: Fermi GBM Final Real-time Localization
  29. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  30. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  31. GRB 241206B: GWAC-F50A optical upper limit
  32. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  33. Fermi GRB 241206A: Global MASTER-Net observations report
  34. GRB 241206A: Fermi GBM Final Real-time Localization
  35. EP241201a: 1.6m Mephisto Optical Upper Limits
  36. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  37. GRB 241204A: Fermi GBM Observation
  38. Fermi GRB 241204A: Global MASTER-Net observations report
  39. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  40. GRB 241201A: GRBAlpha detection
  41. GRB 241204A: Fermi-LAT detection
  42. EP241202b: Upper limits from Fermi-GBM Observations
  43. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  44. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  45. EP241201a: EP-FXT follow-up observations
  46. Konus-Wind detection of GRB 241130A
  47. EP241202b: Global MASTER-Net observations report
  48. IPN triangulation of GRB 241130A
  49. GRB 241130A: EIRSAT-1 GMOD Detection
  50. GRB 241130A: Fermi GBM Detection
  51. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  52. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  53. EP241201a: Kinder optical counterpart candidate
  54. EP241201a: Global MASTER-Net observations report
  55. EP241201a: EP detection of a fast X-ray transient
  56. The EP-WXT trigger 01709126243 is not a real source
  57. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  58. GRB241201B: Fermi GBM Final Localization
  59. GRB241201B: Fermi GBM Final Localization
  60. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  61. Fermi GRB 241201A: Global MASTER-Net observations report
  62. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  63. GRB 241130A: Fermi GBM Final Real-time Localization
  64. GRB 241130A: Fermi GBM Final Real-time Localization
  65. EP241126a: 1.6m Mephisto Optical Upper Limits
  66. GRB 241201A: Fermi GBM Final Real-time Localization
  67. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  68. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  69. Fermi trigger No 754701230: Global MASTER-Net observations report
  70. IPN triangulation of GRB 241128B
  71. Konus-Wind detection of GRB 241114B
  72. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  73. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  74. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  75. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  76. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  77. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  78. GRB 241128A: Swift-BAT refined analysis
  79. GRB 241127A: Swift-BAT refined analysis
  80. EP241126a: NOT optical observations
  81. Swift GRB 241128A: Global MASTER-Net observations report
  82. Fermi-LAT gamma-ray observations of IceCube-241127A
  83. EP241126a: SVOM/VT observations
  84. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  85. GRB 241129A: Fermi GBM Final Real-time Localization
  86. GRB 241128A: NOT optical observations
  87. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  88. Fermi trigger No 754492985: Global MASTER-Net observations report
  89. GRB 241128A: Swift-XRT afterglow detection
  90. GRB 241128A: Swift detection of a burst
  91. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  92. The EP-WXT trigger 01709125191 is not a real source
  93. Swift GRB241127.91: Global MASTER-Net OT detection
  94. EP241126a: WFST Observations
  95. IceCube Alert 241127.59: Global MASTER-Net observations report
  96. GRB 241127A: Swift detection of a burst with an optical counterpart
  97. Swift GRB241127.91: Global MASTER-Net observations report
  98. Swift GRB241127.91: Global MASTER-Net OT detection
  99. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  100. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits

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