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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"

8486 results found.

  1. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  2. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  3. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  4. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  5. LIGO/Virgo/KAGRA S241126dm: Retraction of GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  7. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  8. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  9. GRB 241026A: radio detection with the VLA
  10. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  11. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  12. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  13. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  14. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  15. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  16. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  17. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  18. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  19. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  21. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  22. GRB241120A: OHP/T193 optical observations
  23. GRB 241120A: Mondy and AbAO optical observations
  24. GRB 241112B: Mephisto further optical observations
  25. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  26. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  27. Updates to IceCube realtime alert system for muon tracks
  28. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  29. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  30. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  31. GRB 241113B: Mephisto upper limits
  32. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  33. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  34. EP241113a: No Detection in Fermi-GBM Observations
  35. GRB 241115A: Swift detection of a burst
  36. EP 241113a: LBT possible optical counterpart
  37. GRB 241113B: KAIT Optical Afterglow Candidate
  38. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  39. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  40. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  41. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  42. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  43. Konus-Wind detection of GRB 241107A (short/hard)
  44. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  45. GRB 241113B: Swift ToO observations
  46. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  47. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  48. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  49. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  50. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  51. GRB 241112B: Mephisto optical upper limits
  52. GRB 241112B: Swift ToO observations
  53. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  54. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  55. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  56. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  57. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  59. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  60. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  61. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  62. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  63. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  64. GRB 241108A: Swift ToO observations
  65. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  66. EP241107a: Kinder optical follow-up observations
  67. GRB 241025A: radio detection with the VLA
  68. EP241101a: CrAO ZTSH optical observations
  69. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  70. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  71. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  72. GRB 241105A: Swift ToO observations
  73. GRB 241104A: Swift ToO observations
  74. GRB 241104A: NOT optical non-detection
  75. GRB 241105A: GOTO tentative optical counterpart candidate
  76. GRB 241104A: SVOM/VT optical candidate
  77. GRB 240821A: further radio observations with the VLA
  78. EP241101a: EP-FXT observations update
  79. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  81. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  82. EP241103a: Swift XRT detection and improved X-ray position
  83. EP241101a: Optical upper limits with Kinder observations
  84. EP241101a: OHP/T193 optical observations
  85. EP241103a: Gemini optical limits
  86. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  87. S241102cy: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  89. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  90. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  91. GRB 241030B: Montarrenti Observatory optical upper limit
  92. GRB241030B: GRANDMA/TAROT Upper Limit
  93. GRB 241030B: Swift detection of a burst
  94. GRB 240912A: radio detection with the VLA
  95. GRB 241030A: AKO Optical Afterglow Detection
  96. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  97. GRB 241029A: TRT optical afterglow candidate detection
  98. GRB 241029A: Swift ToO observations
  99. GRB 241026A: Swift detection of a burst
  100. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO

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