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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"

45728 results found.

  1. Swift GRB241127.91: Global MASTER-Net OT detection
  2. EP241126a: WFST Observations
  3. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  4. IceCube Alert 241127.59: Global MASTER-Net observations report
  5. GRB 241127A: Swift detection of a burst with an optical counterpart
  6. Swift GRB241127.91: Global MASTER-Net observations report
  7. Swift GRB241127.91: Global MASTER-Net OT detection
  8. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  9. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  10. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  11. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  12. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  13. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  14. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  15. EP241126a: Optical Upper limits with Kinder observations
  16. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  17. GRB 241126A: SVOM/GRM observation
  18. IPN triangulation of GRB 241114B
  19. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  20. EP241126a: EP-FXT follow-up observation update
  21. EP241126a: GSP detects optical counterpart
  22. EP241126a: TRT optical counterpart detection
  23. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  24. EP241126a: EP detection of a fast X-ray transient
  25. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  26. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  27. LIGO/Virgo/KAGRA S241126dm: Retraction of GW compact binary merger candidate
  28. Trigger_18947: Swift ToO observations (retracted)
  29. GRB 241113B: EP-FXT afterglow detection
  30. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  31. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  32. SVOM/GRM detection of a short burst from SGR 1830
  33. GECAM detection of a short burst from SGR 1830
  34. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  35. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  36. Konus-Wind detection of GRB 241115D / EP 241115a
  37. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  38. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  39. GRB 241026A: radio detection with the VLA
  40. EP241125a: Optical upper limit with Kinder observations
  41. EP241125a: EP detection of an X-ray transient
  42. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  43. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  44. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  45. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  46. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  47. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  48. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  49. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  50. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  51. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  52. GRB 241120A: GRBAlpha detection
  53. GRB 241113B: SVOM/VT optical afterglow observations
  54. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  55. Konus-Wind detection of GRB 241117A
  56. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  57. GRB 241105A: ATCA radio detection
  58. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  59. IPN triangulation of GRB 241117A
  60. GRB 241026A: VIRT Optical Upper Limit
  61. GRB 241025A: VIRT Optical Upper Limit
  62. Konus-Wind detection of GRB 241120A
  63. GRB241120A: OHP/T193 optical observations
  64. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  65. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  66. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  67. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  68. GRB 241120A: Mondy and AbAO optical observations
  69. EP241119a: Optical upper limits with Kinder observations
  70. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  71. EP241119a: GIT optical upper limits
  72. GRB 241113A: Possible ATCA Radio detection
  73. EP241119a : J-band observations with WINTER
  74. GRB 241120A: Fermi GBM Observation
  75. GRB 241114B: Insight-HXMT/HE detection
  76. Integral GRB241120.25: Global MASTER-Net observations report
  77. EP241119a: Global MASTER-Net observations report
  78. EP241119a: EP detection of a fast X-ray transient
  79. GRB241120A: a long GRB detected by INTEGRAL
  80. GRB 241120A: Fermi GBM Final Real-time Localization
  81. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241112B: Mephisto further optical observations
  83. GRB 241119A: Fermi GBM Final Real-time Localization
  84. GRB 241030A: J-band observations
  85. GRB 241115a: PRIME near-infrared upper limits
  86. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  87. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  88. GRB 241115B: Fermi GBM Observation
  89. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  90. Fermi GRB 241118A: Global MASTER-Net observations report
  91. GRB 241118A: Fermi GBM Final Real-time Localization
  92. Updates to IceCube realtime alert system for muon tracks
  93. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  94. GRB 241117A: Fermi GBM Detection
  95. Fermi GRB 241117B: Global MASTER-Net observations report
  96. GRB 241117B: Fermi GBM Final Real-time Localization
  97. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  98. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  99. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  100. Fermi GRB 241117A: Global MASTER-Net observations report

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