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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"
  1. EP241201a: 1.6m Mephisto Optical Upper Limits
  2. GRB 241204A: COLIBRÍ Optical Upper Limit
  3. EP241202b: KAIT optical upper limit
  4. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  5. GRB 241204A: DDOTI Upper Limits on the Afterglow
  6. GRB 241204A: Fermi GBM Observation
  7. Fermi GRB 241204A: Global MASTER-Net observations report
  8. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  9. GRB 241128A : RAPAS follow-up observations
  10. GRB 241201A: GRBAlpha detection
  11. GRB 241204A: Fermi-LAT detection
  12. EP241202b: Upper limits from Fermi-GBM Observations
  13. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  14. EP241202b: Kinder optical counterpart candidate
  15. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  16. GRB 241113B : RAPAS follow-up observation
  17. EP241201a: EP-FXT follow-up observations
  18. Konus-Wind detection of GRB 241130A
  19. EP241202b: Global MASTER-Net observations report
  20. EP241201a: BOOTES-5 optical upper limit
  21. EP241202b: EP detection of a fast X-ray transient
  22. EP241201a: NOT optical observations
  23. IPN triangulation of GRB 241130A
  24. GRB 241130A: EIRSAT-1 GMOD Detection
  25. GRB 241128A: Swift/UVOT Upper Limits
  26. GRB 241130A: Fermi GBM Detection
  27. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  28. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  29. EP241201a: Kinder optical counterpart candidate
  30. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  31. EP241201a: Global MASTER-Net observations report
  32. EP241201a: EP detection of a fast X-ray transient
  33. The EP-WXT trigger 01709126243 is not a real source
  34. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  35. GRB241201B: Fermi GBM Final Localization
  36. GRB241201B: Fermi GBM Final Localization
  37. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  38. EP241126a: SOAR observations of the optical counterpart
  39. Fermi GRB 241201A: Global MASTER-Net observations report
  40. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  41. GRB 241130A: Fermi GBM Final Real-time Localization
  42. GRB 241130A: Fermi GBM Final Real-time Localization
  43. EP241126a: 1.6m Mephisto Optical Upper Limits
  44. GRB 241201A: Fermi GBM Final Real-time Localization
  45. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  47. Fermi trigger No 754701230: Global MASTER-Net observations report
  48. IPN triangulation of GRB 241128B
  49. Konus-Wind detection of GRB 241114B
  50. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  51. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  52. GRB 241128A: AbAO optical upper limit
  53. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  54. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  55. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  56. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  57. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  58. GRB 241128C: SVOM/GRM observation
  59. GRB 241128B: SVOM/GRM observation
  60. GRB 241128A: Swift-BAT refined analysis
  61. GRB 241127A: Swift-BAT refined analysis
  62. EP241126a: NOT optical observations
  63. GRB 241127A: PRIME near-infrared detection
  64. GRB 241128A: Mondy optical observations
  65. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  66. Swift-XRT observations of IceCube -241127A
  67. Swift GRB 241128A: Global MASTER-Net observations report
  68. Fermi-LAT gamma-ray observations of IceCube-241127A
  69. EP241126a: SVOM/VT observations
  70. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  71. GRB 241128A: Swift-XRT refined Analysis
  72. GRB 241129A: Fermi GBM Final Real-time Localization
  73. GRB 241128A: Enhanced Swift-XRT position
  74. GRB 241128A: NOT optical observations
  75. GRB 241128A: LCO optical detection
  76. GRB 241128A: 1.5m OSN optical afterglow detection
  77. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  78. Fermi trigger No 754492985: Global MASTER-Net observations report
  79. GRB 241128A: Swift-XRT afterglow detection
  80. GRB 241128A: Swift detection of a burst
  81. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  82. GRB 241127A: Swift/UVOT Detection
  83. GRB 241127A: Swift-XRT refined Analysis
  84. GRB 241127A: SVOM/GRM observation
  85. GRB 241127A: Enhanced Swift-XRT position
  86. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  87. The EP-WXT trigger 01709125191 is not a real source
  88. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  89. Swift GRB241127.91: Global MASTER-Net OT detection
  90. EP241126a: WFST Observations
  91. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  92. IceCube Alert 241127.59: Global MASTER-Net observations report
  93. GRB 241127A: Swift detection of a burst with an optical counterpart
  94. Swift GRB241127.91: Global MASTER-Net observations report
  95. Swift GRB241127.91: Global MASTER-Net OT detection
  96. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  97. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  98. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  99. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  100. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)

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