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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"

43156 results found.

  1. Konus-Wind detection of GRB 241018A
  2. GRB 241018A: SVOM/GRM observation
  3. GRB 241018A/sb24101802: Mephisto optical upper limit
  4. GRB 241017A/sb24101702: Mephisto optical upper limit
  5. GRB 241018A: BOOTES-4/MET optical upper limit
  6. GRB 241018A: SVOM/VT further analysis and counterpart confirmed
  7. GRB 241018A: GROWTH-India telescope optical upper limit
  8. GRB241018A: XingLong Optical Upper Limit
  9. GRB 241018A: Swift-XRT observations
  10. GRB 241018A: REM optical/NIR upper limits
  11. GRB 241018A: NOT optical observations
  12. GRB 241017A: SVOM/VT follow-up and optical upper limit
  13. GRB 241018A: SVOM/VT follow-up and optical candidate
  14. GRB 241018A: LCO/0.4m optical upper limits
  15. GRB 241018A: Swift ToO observations
  16. GRB 241006A: VIRT Optical Upper Limit
  17. GRB 240727A: VIRT Optical Upper Limit
  18. GRB 241018A: X-ray afterglow candidate observed by MXT
  19. GRB 241016B: Fermi GBM Observations
  20. GRB 241018A: Detection of a bright long GRB by SVOM
  21. GRB 241017A: Swift-XRT observations
  22. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  23. GRB 241001A: EP-FXT afterglow detection
  24. GRB 241017A: GROWTH-India Telescope optical upper limit
  25. GRB241017A: TOO Observations by SVOM/MXT
  26. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  27. GRB 241017A: J-band upper limit from WINTER
  28. Fermi trigger No 750788395: Global MASTER-Net observations report
  29. GRB 241016B: SVOM/GRM observation
  30. GRB241016C: Fermi GBM Final Localization
  31. GRB 241017A: Swift ToO observations
  32. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  33. Fermi GRB 241016B: Global MASTER-Net observations report
  34. GRB 241016B: Fermi GBM Final Localization
  35. Fermi GRB 241016A: Global MASTER-Net observations report
  36. GRB 241016A: Fermi GBM Final Real-time Localization
  37. IceCube Alert 241016.04: Global MASTER-Net observations report
  38. GRB 241010A: Swift-BAT refined analysis
  39. GRB 241013B: Fermi GBM Observation
  40. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  41. GRB 241013A: Fermi GBM Observation
  42. GRB 240916A: radio detection with the VLA
  43. GRB241013A: REM observations
  44. GRB 241009A: LCO optical upper limits
  45. GRB 241013B: SVOM/GRM observation
  46. Fermi GRB 241013B: Global MASTER-Net observations report
  47. Integral GRB241013.04: Global MASTER-Net observations report
  48. GRB 241013B: Fermi GBM Final Real-time Localization
  49. GRB 241013A: a long GRB detected by INTEGRAL
  50. GRB 241013A: Fermi GBM Final Real-time Localization
  51. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  52. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  53. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  54. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  55. GRB 241011A: Fermi GBM Final Real-time Localization
  56. GRB 241009A: GRANDMA optical upper limits
  57. GRB 241009A: Swift-XRT afterglow detection
  58. GRB 241010A: JinShan optical observations and potential host galaxy
  59. GRB 241006A: ATCA Radio Upper Limits
  60. GRB 241010A: Swift-XRT refined Analysis
  61. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  62. Fermi trigger No 750211959: Global MASTER-Net observations report
  63. Swift GRB 241010A: Global MASTER-Net observations report
  64. Fermi trigger No 750291012: Global MASTER-Net observations report
  65. GRB 241010A: J-band observations with WINTER
  66. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  67. Fermi GRB 241010B: Global MASTER-Net observations report
  68. GRB 241010B: Fermi GBM Final Real-time Localization
  69. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  70. GRB 241010A: Enhanced Swift-XRT position
  71. GRB 241010A: LCO optical observations
  72. GRB 241010A: Swift detection of a burst with an optical counterpart
  73. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  74. GRB 241006A: Swift-BAT refined analysis
  75. GRB 241009A: Swift ToO observations
  76. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  77. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  78. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  79. GRB 241008A: Fermi GBM Observation
  80. GRB 241008A: Fermi-LAT detection
  81. GRB 241002B: Swift-XRT afterglow detection
  82. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  83. GRB 241002A: NOT optical upper limits
  84. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  85. Fermi GRB 241008A: Global MASTER-Net observations report
  86. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  87. GRB 241008A: Fermi GBM Final Real-time Localization
  88. IceCube-241006A: No candidates from the Zwicky Transient Facility
  89. GRB 241006A: GRANDMA optical upper limits
  90. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  91. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  92. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  93. GRB 240910A: LBT optical observations
  94. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  95. GRB 241006A: Swift-XRT refined Analysis
  96. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  97. GRB 241006A: PRIME near-infrared upper limits
  98. GRB 241006A: Swift/UVOT Upper Limits
  99. GRB 241006A: SVOM/VT follow-up and optical upper limit
  100. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate

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