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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"

45845 results found.

  1. GRB 241002A: Enhanced Swift-XRT position
  2. GRB 241001A: BOOTES-6/DPRT optical upper limit
  3. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  4. GRB 241002A: Swift detection of a burst
  5. LIGO/Virgo/KAGRA S240930du: Updated Sky localization
  6. GRB 240930B: Fermi GBM Observation
  7. GRB 241001A: Swift ToO observations
  8. GRB 240930B: GRBAlpha detection
  9. GRB 240929A: GRBAlpha detection
  10. EP240930a : KAIT optical upper limit
  11. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  12. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  13. EP240930a: EP-FXT follow-up observation update
  14. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  15. EP240930a: GOTO optical upper limits
  16. GRB 240929A: SVOM/GRM observation
  17. EP EP240930a: Global MASTER-Net observations report
  18. EP240930a: EP-WXT detection of a fast X-ray transient
  19. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  20. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  21. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  22. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  23. AMON NuEM 240926A: Swift XRT Follow-up
  24. GRB 240929A : Leavitt Observatory optical upper limit
  25. Fermi GRB 240930B: Global MASTER-Net observations report
  26. GRB 240930B: Fermi GBM Final Real-time Localization
  27. IPN triangulation of GRB 240926A
  28. GRB 240825A: LBT optical observations
  29. GRB 240928A: SVOM/GRM observation
  30. Fermi GRB 240930A: Global MASTER-Net observations report
  31. Fermi Gamma-ray Burst Monitor trigger 749362078/240930172 (GRB 240930A) is not a GRB
  32. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  33. GRB 240930A: Fermi GBM Final Real-time Localization
  34. Fermi trigger No 749339671: Global MASTER-Net observations report
  35. Fermi Gamma-ray Burst Monitor trigger 749339671/240929913 is not a GRB
  36. GRB 240929A long GRB detected by INTEGRAL
  37. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  38. Fermi GRB 240929A: Global MASTER-Net observations report
  39. GRB 240929A: Fermi GBM Final Real-time Localization
  40. Integral GRB240929.83: Global MASTER-Net observations report
  41. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  42. Konus-Wind detection of GRB 240912A
  43. Swift Trigger 1256950 is probably not a GRB
  44. Fermi Gamma-ray Burst Monitor trigger 749191601/240928199 is not a GRB
  45. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  47. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  48. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  49. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  50. GRB 240926A: SVOM/GRM observation
  51. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  52. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240926A
  53. Konus-Wind detection of GRB 240905B
  54. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  55. GW S240915b and S240919bn : Swift UVOT follow-up
  56. EP240919a / GRB 240919A: SVOM/VT upper limit
  57. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  58. EP240918b and EP240918c: EP-FXT follow-up observations
  59. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  60. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  61. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  62. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  63. Konus-Wind detection of GRB 240918B
  64. IPN triangulation of GRB 240918B
  65. GRB 240905B: VZLUSAT-2 detection
  66. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  67. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  68. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  69. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  70. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  71. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  72. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  73. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  74. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo S240919bn: GOTO optical upper limits
  76. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  77. GRB 240918B: AstroSat CZTI detection
  78. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  80. EP240919a: EP-FXT follow-up observation update
  81. EP240913A/GRB 240913C: AbAO optical upper limit
  82. EP240919a / GRB 240919A: Mondy optical upper limit
  83. EP240913a/GRB 240913C: 1.6m Mephisto observations
  84. EP240918a: SVOM/VT upper limit
  85. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  86. EP240919a / GRB 240919A: REM optical and NIR upper limits
  87. EP240919a / GRB 240919A: KAIT optical upper limit
  88. EP240918b and EP240918c: Optical upper limits with Kinder observations
  89. GRB 240414A: further radio observations with the VLA
  90. EP240919a: Optical upper limit with Kinder observations
  91. GRB 240919A / EP240919a: SVOM/GRM observation
  92. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  93. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  94. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  95. EP EP240919a: Global MASTER-Net observations report
  96. GRB 240910A: radio detection with the VLA
  97. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  98. EP240919a: NOT and Gemini optical observations
  99. EP240919a: GOTO optical upper limits
  100. EP240919a: JinShan optical upper limits

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