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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"

28294 results found.

  1. GRB 241120A: Fermi GBM Observation
  2. EP241119a: EP detection of a fast X-ray transient
  3. GRB241120A: a long GRB detected by INTEGRAL
  4. GRB 241112B: Mephisto further optical observations
  5. GRB 241030A: J-band observations
  6. GRB 241115a: PRIME near-infrared upper limits
  7. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  8. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  9. GRB 241115B: Fermi GBM Observation
  10. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  11. Updates to IceCube realtime alert system for muon tracks
  12. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  13. GRB 241117A: Fermi GBM Detection
  14. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  15. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  16. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  17. GRB 241115C: Fermi GBM Observation
  18. GRB 241115A: Swift-XRT afterglow detection
  19. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  20. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  21. GRB 241115A: Mephisto upper limits
  22. GRB 241113B: Mephisto upper limits
  23. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  24. GRB 241115D / EP 241115a: SVOM/GRM observation
  25. EP241113a: Swift XRT weak detection
  26. GRB 241115A: Fermi GBM Observation
  27. GRB 241115A: LCOGT Optical Upper Limits
  28. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  29. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  30. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  31. EP241115a: EP detection of a fast X-ray transient
  32. Swift GRB 241115A: Global MASTER-Net observations report
  33. Fermi GRB 241115A: Global MASTER-Net observations report
  34. GRB 241115A: Swift detection of a burst
  35. EP 241113a: LBT possible optical counterpart
  36. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  37. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  38. GRB 241113A: Swift-BAT refined analysis
  39. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  40. GRB 241113A: PRIME near-infrared upper limits
  41. EP241113a: Global MASTER-Net observations report
  42. GRB 241113B: J-band upper limit from WINTER
  43. GRB 241113A: J-band observations with WINTER
  44. EP241113a : J-band observations with WINTER
  45. GRB 241030A: LCO optical observation
  46. GRB 241113B: Swift-XRT observations
  47. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  48. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  49. EP241113b/GRB 241113B: EP detection of GRB 241113B
  50. Fermi-LAT gamma-ray observations of IceCube-241113A
  51. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  52. GRB 241113A: Swift-XRT refined Analysis
  53. GRB 241113A: Swift/UVOT Detection
  54. GRB 241113A: REM detection of the optical/NIR afterglow
  55. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  56. GRB 241113A: LCO optical observations
  57. GRB 241112B: GMG Optical Upper Limit
  58. GRB 241113A: Enhanced Swift-XRT position
  59. GRB241113A: LCOGT (40-cm) optical counterpart detection
  60. GRB 241113A: Swift detection of a burst with an optical counterpart
  61. SVOM/GRM detection of a short burst from SGR 1E1841-045
  62. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  63. GRB 241112B: AbAO optical upper limit
  64. GRB 241107A: GROWTH-India telescope optical upper limit
  65. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  66. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  67. GRB 241112B: Swift-XRT afterglow detection
  68. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  69. GRB 241112B: Mephisto optical upper limits
  70. GRB 241112B: GOTO optical upper limits
  71. GRB 241107A: INTEGRAL IBIS localization
  72. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  73. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  74. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  75. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  76. IPN triangulation of GRB 241107A (short/hard)
  77. GRB 241025C: VZLUSAT-2 detection
  78. GRB 241025A: VZLUSAT-2 detection
  79. GRB 241018A: cubesat Avion detection
  80. GRB 241030B: TESS detection of optical counterpart
  81. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  82. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  83. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  85. Integral GRB241109.89: Global MASTER-Net observations report
  86. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  87. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  88. EP241107a: AbAO optical upper limit
  89. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  90. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  91. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  92. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  93. EP241109a: confirmation of a stellar flare by BOOTES-7
  94. GRB 241108A: Swift-XRT observations
  95. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  96. EP241107a: KAIT optical observations
  97. GRB 241030A: TESS observations
  98. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  99. EP241107a: Kinder optical follow-up observations
  100. GRB 241025A: radio detection with the VLA

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