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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"

12112 results found.

  1. Fermi trigger No 751449953: Global MASTER-Net observations report
  2. EP241021a: SAO RAS optical observations
  3. EP241021a: EP-FXT follow-up observation update
  4. GRB241017A: 1.3m DFOT optical upper limit
  5. EP241021a: EP detection of a fast X-ray transient
  6. IceCube-Cascade 241019A: Upper limits from a search for additional neutrino events in IceCube
  7. Konus-Wind detection of GRB 241018A
  8. GRB 241018A/sb24101802: Mephisto optical upper limit
  9. GRB 240727A: VIRT Optical Upper Limit
  10. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  11. Fermi trigger No 750788395: Global MASTER-Net observations report
  12. Fermi GRB 241016B: Global MASTER-Net observations report
  13. Fermi GRB 241016A: Global MASTER-Net observations report
  14. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  15. GRB241013A: REM observations
  16. GRB 241013A: a long GRB detected by INTEGRAL
  17. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  18. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  19. GRB 241011A: Fermi GBM Final Real-time Localization
  20. GRB 241010A: Swift-XRT refined Analysis
  21. Fermi trigger No 750211959: Global MASTER-Net observations report
  22. Fermi trigger No 750291012: Global MASTER-Net observations report
  23. GRB 241010A: Swift detection of a burst with an optical counterpart
  24. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  25. GRB 241008A: Fermi-LAT detection
  26. GRB 241002B: Swift-XRT afterglow detection
  27. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  28. GRB 240910A: LBT optical observations
  29. GRB 241006A: Swift-XRT refined Analysis
  30. IceCube Alert 241006.94: Global MASTER-Net observations report
  31. GRB 241006A: Swift detection of a burst
  32. Swift GRB241006.91: Global MASTER-Net observations report
  33. EP trigger ID 01709065118: the X-ray transient is likely a stellar flare event
  34. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  35. Fermi trigger No 749693019: Global MASTER-Net observations report
  36. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  37. Konus-Wind detection of GRB 240926A
  38. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  39. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  40. EP240930a: Liverpool Telescope observations
  41. GRB 241002A: Swift-XRT refined Analysis
  42. GRB 241002B: GOTO optical counterpart candidate
  43. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  44. Fermi GRB 241002B: Global MASTER-Net observations report
  45. GRB 241002A: Swift detection of a burst
  46. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  47. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  48. EP240930a: GOTO optical upper limits
  49. EP EP240930a: Global MASTER-Net observations report
  50. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  51. GRB 240929A : Leavitt Observatory optical upper limit
  52. Fermi GRB 240930B: Global MASTER-Net observations report
  53. Fermi GRB 240930A: Global MASTER-Net observations report
  54. GRB 240929A long GRB detected by INTEGRAL
  55. Fermi GRB 240929A: Global MASTER-Net observations report
  56. Konus-Wind detection of GRB 240912A
  57. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  58. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  59. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  60. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  61. Konus-Wind detection of GRB 240905B
  62. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  63. EP240918b and EP240918c: EP-FXT follow-up observations
  64. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  65. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  66. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  67. Konus-Wind detection of GRB 240918B
  68. IPN triangulation of GRB 240918B
  69. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  70. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo S240919bn: GOTO optical upper limits
  72. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  73. GRB 240918B: AstroSat CZTI detection
  74. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  75. EP240919a: EP-FXT follow-up observation update
  76. EP240919a / GRB 240919A: Mondy optical upper limit
  77. EP240919a: Optical upper limit with Kinder observations
  78. GRB 240919A / EP240919a: SVOM/GRM observation
  79. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  80. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  81. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  82. EP EP240919a: Global MASTER-Net observations report
  83. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  84. EP240919a: NOT and Gemini optical observations
  85. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  86. EP240919a: EP-WXT detection of a fast X-ray transient
  87. GRB 240918B: Fermi GBM Detection
  88. EP240918a: EP observation update
  89. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  90. Fermi GRB 240918A: Global MASTER-Net observations report
  91. GRB 240918A: Fermi GBM Final Real-time Localization
  92. EP EP240918a: Global MASTER-Net observations report
  93. EP240918a: YAHPT Optical Upper Limit
  94. EP240918a: Optical upper limits with Kinder observations
  95. EP240918a: an X-ray transient detected by Einstein Probe
  96. GRB 240916A: NOT optical observation
  97. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  98. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  99. EP EP240913a: Global MASTER-Net observations report
  100. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations

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