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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"

43140 results found.

  1. GRB 240727A: VIRT Optical Upper Limit
  2. GRB 241018A: X-ray afterglow candidate observed by MXT
  3. GRB 241016B: Fermi GBM Observations
  4. GRB 241018A: Detection of a bright long GRB by SVOM
  5. GRB 241017A: Swift-XRT observations
  6. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  7. GRB 241001A: EP-FXT afterglow detection
  8. GRB 241017A: GROWTH-India Telescope optical upper limit
  9. GRB241017A: TOO Observations by SVOM/MXT
  10. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  11. GRB 241017A: J-band upper limit from WINTER
  12. Fermi trigger No 750788395: Global MASTER-Net observations report
  13. GRB 241016B: SVOM/GRM observation
  14. GRB241016C: Fermi GBM Final Localization
  15. GRB 241017A: Swift ToO observations
  16. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  17. Fermi GRB 241016B: Global MASTER-Net observations report
  18. GRB 241016B: Fermi GBM Final Localization
  19. Fermi GRB 241016A: Global MASTER-Net observations report
  20. GRB 241016A: Fermi GBM Final Real-time Localization
  21. IceCube Alert 241016.04: Global MASTER-Net observations report
  22. GRB 241010A: Swift-BAT refined analysis
  23. GRB 241013B: Fermi GBM Observation
  24. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  25. GRB 241013A: Fermi GBM Observation
  26. GRB 240916A: radio detection with the VLA
  27. GRB241013A: REM observations
  28. GRB 241009A: LCO optical upper limits
  29. GRB 241013B: SVOM/GRM observation
  30. Fermi GRB 241013B: Global MASTER-Net observations report
  31. Integral GRB241013.04: Global MASTER-Net observations report
  32. GRB 241013B: Fermi GBM Final Real-time Localization
  33. GRB 241013A: a long GRB detected by INTEGRAL
  34. GRB 241013A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  36. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  37. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  38. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  39. GRB 241011A: Fermi GBM Final Real-time Localization
  40. GRB 241009A: GRANDMA optical upper limits
  41. GRB 241009A: Swift-XRT afterglow detection
  42. GRB 241010A: JinShan optical observations and potential host galaxy
  43. GRB 241006A: ATCA Radio Upper Limits
  44. GRB 241010A: Swift-XRT refined Analysis
  45. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  46. Fermi trigger No 750211959: Global MASTER-Net observations report
  47. Swift GRB 241010A: Global MASTER-Net observations report
  48. Fermi trigger No 750291012: Global MASTER-Net observations report
  49. GRB 241010A: J-band observations with WINTER
  50. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  51. Fermi GRB 241010B: Global MASTER-Net observations report
  52. GRB 241010B: Fermi GBM Final Real-time Localization
  53. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  54. GRB 241010A: Enhanced Swift-XRT position
  55. GRB 241010A: LCO optical observations
  56. GRB 241010A: Swift detection of a burst with an optical counterpart
  57. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  58. GRB 241006A: Swift-BAT refined analysis
  59. GRB 241009A: Swift ToO observations
  60. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  61. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  62. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  63. GRB 241008A: Fermi GBM Observation
  64. GRB 241008A: Fermi-LAT detection
  65. GRB 241002B: Swift-XRT afterglow detection
  66. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  67. GRB 241002A: NOT optical upper limits
  68. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  69. Fermi GRB 241008A: Global MASTER-Net observations report
  70. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  71. GRB 241008A: Fermi GBM Final Real-time Localization
  72. IceCube-241006A: No candidates from the Zwicky Transient Facility
  73. GRB 241006A: GRANDMA optical upper limits
  74. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  75. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  76. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  77. GRB 240910A: LBT optical observations
  78. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  79. GRB 241006A: Swift-XRT refined Analysis
  80. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  81. GRB 241006A: PRIME near-infrared upper limits
  82. GRB 241006A: Swift/UVOT Upper Limits
  83. GRB 241006A: SVOM/VT follow-up and optical upper limit
  84. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  85. IceCube Alert 241006.94: Global MASTER-Net observations report
  86. GRB 241001A: Swift-XRT afterglow detection
  87. GRB 241006A: Enhanced Swift-XRT position
  88. IceCube-241006A - IceCube observation of a high-energy neutrino candidate track-like event
  89. GRB 241006A: Swift detection of a burst
  90. Swift GRB241006.91: Global MASTER-Net observations report
  91. GRB 240930B: SVOM/C-GFT optical upper limit
  92. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S241005bo: Retraction of GW compact binary merger candidate
  94. Fermi trigger No 749721670: Global MASTER-Net observations report
  95. GRB 241004A: SVOM/GRM observation
  96. EP trigger ID 01709065118: the X-ray transient is likely a stellar flare event
  97. GRB 240930B / EP 240930a: SVOM/GRM observation
  98. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  99. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  100. GRB 241002B: Fermi GBM Observation

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