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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

4055 results found.

  1. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  3. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  4. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  5. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  7. EP241109a: confirmation of a stellar flare by BOOTES-7
  8. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  10. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  11. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  12. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  13. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  14. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  15. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  16. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  17. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  18. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  19. LIGO/Virgo/KAGRA S241101ee: Updated Sky localization
  20. S241102cy: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  22. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  23. LIGO/Virgo/KAGRA S241101ee: Identification of a GW compact binary merger candidate
  24. GRB 241029A: Fermi GBM Observation
  25. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  26. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  27. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  28. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  29. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  30. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  31. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  32. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  33. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  34. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  36. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  38. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  40. LIGO/Virgo/KAGRA S241005bo: Retraction of GW compact binary merger candidate
  41. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  42. LIGO/Virgo/KAGRA S240925n: Updated Sky localization
  43. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  44. LIGO/Virgo/KAGRA S241002e: Updated Sky localization
  45. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  46. LIGO/Virgo/KAGRA S240930du: Updated Sky localization
  47. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  48. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  49. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  50. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  51. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  52. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  53. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  54. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  55. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  56. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  57. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  59. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  60. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  61. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  62. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  63. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  64. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  66. LIGO/Virgo S240919bn: GOTO optical upper limits
  67. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  68. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  69. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  70. EP240913a/GRB 240913C: 1.6m Mephisto observations
  71. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  72. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  73. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  74. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  75. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  76. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  77. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  78. EP240918a: YAHPT Optical Upper Limit
  79. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  81. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  82. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  83. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  84. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  85. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  86. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  87. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  89. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  90. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  91. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  92. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  95. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  96. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  99. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  100. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO

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