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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45809 results found.

  1. EP241201a: EP-FXT follow-up observations
  2. Konus-Wind detection of GRB 241130A
  3. EP241202b: Global MASTER-Net observations report
  4. EP241201a: BOOTES-5 optical upper limit
  5. EP241202b: EP detection of a fast X-ray transient
  6. EP241201a: NOT optical observations
  7. IPN triangulation of GRB 241130A
  8. GRB 241130A: EIRSAT-1 GMOD Detection
  9. GRB 241128A: Swift/UVOT Upper Limits
  10. GRB 241130A: Fermi GBM Detection
  11. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  12. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  13. EP241201a: Kinder optical counterpart candidate
  14. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  15. EP241201a: Global MASTER-Net observations report
  16. EP241201a: EP detection of a fast X-ray transient
  17. The EP-WXT trigger 01709126243 is not a real source
  18. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  19. GRB241201B: Fermi GBM Final Localization
  20. GRB241201B: Fermi GBM Final Localization
  21. LIGO/Virgo/KAGRA S241201ac: Updated Sky localization
  22. EP241126a: SOAR observations of the optical counterpart
  23. Fermi GRB 241201A: Global MASTER-Net observations report
  24. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  25. GRB 241130A: Fermi GBM Final Real-time Localization
  26. GRB 241130A: Fermi GBM Final Real-time Localization
  27. EP241126a: 1.6m Mephisto Optical Upper Limits
  28. GRB 241201A: Fermi GBM Final Real-time Localization
  29. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S241130be: Updated Sky localization
  31. Fermi trigger No 754701230: Global MASTER-Net observations report
  32. IPN triangulation of GRB 241128B
  33. Konus-Wind detection of GRB 241114B
  34. LIGO/Virgo/KAGRA S241130n: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  36. GRB 241128A: AbAO optical upper limit
  37. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  38. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S241129aa: Updated Sky localization
  40. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  41. SVOM/GRM observation of a short burst from soft gamma repeater Kes 73
  42. GRB 241128C: SVOM/GRM observation
  43. GRB 241128B: SVOM/GRM observation
  44. GRB 241128A: Swift-BAT refined analysis
  45. GRB 241127A: Swift-BAT refined analysis
  46. EP241126a: NOT optical observations
  47. GRB 241127A: PRIME near-infrared detection
  48. GRB 241128A: Mondy optical observations
  49. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  50. Swift-XRT observations of IceCube -241127A
  51. Swift GRB 241128A: Global MASTER-Net observations report
  52. Fermi-LAT gamma-ray observations of IceCube-241127A
  53. EP241126a: SVOM/VT observations
  54. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  55. GRB 241128A: Swift-XRT refined Analysis
  56. GRB 241129A: Fermi GBM Final Real-time Localization
  57. GRB 241128A: Enhanced Swift-XRT position
  58. GRB 241128A: NOT optical observations
  59. GRB 241128A: LCO optical detection
  60. GRB 241128A: 1.5m OSN optical afterglow detection
  61. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  62. Fermi trigger No 754492985: Global MASTER-Net observations report
  63. GRB 241128A: Swift-XRT afterglow detection
  64. GRB 241128A: Swift detection of a burst
  65. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  66. GRB 241127A: Swift/UVOT Detection
  67. GRB 241127A: Swift-XRT refined Analysis
  68. GRB 241127A: SVOM/GRM observation
  69. GRB 241127A: Enhanced Swift-XRT position
  70. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  71. The EP-WXT trigger 01709125191 is not a real source
  72. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  73. Swift GRB241127.91: Global MASTER-Net OT detection
  74. EP241126a: WFST Observations
  75. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  76. IceCube Alert 241127.59: Global MASTER-Net observations report
  77. GRB 241127A: Swift detection of a burst with an optical counterpart
  78. Swift GRB241127.91: Global MASTER-Net observations report
  79. Swift GRB241127.91: Global MASTER-Net OT detection
  80. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  81. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  82. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  83. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  84. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  85. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  86. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  87. EP241126a: Optical Upper limits with Kinder observations
  88. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  89. GRB 241126A: SVOM/GRM observation
  90. IPN triangulation of GRB 241114B
  91. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  92. EP241126a: EP-FXT follow-up observation update
  93. EP241126a: GSP detects optical counterpart
  94. EP241126a: TRT optical counterpart detection
  95. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  96. EP241126a: EP detection of a fast X-ray transient
  97. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  98. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  99. LIGO/Virgo/KAGRA S241126dm: Retraction of GW compact binary merger candidate
  100. Trigger_18947: Swift ToO observations (retracted)

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