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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"

43163 results found.

  1. Integral GRB240929.83: Global MASTER-Net observations report
  2. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  3. Konus-Wind detection of GRB 240912A
  4. Swift Trigger 1256950 is probably not a GRB
  5. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  6. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  7. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  8. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  9. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  10. GRB 240926A: SVOM/GRM observation
  11. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  12. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240926A
  13. Konus-Wind detection of GRB 240905B
  14. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  15. GW S240915b and S240919bn : Swift UVOT follow-up
  16. EP240919a / GRB 240919A: SVOM/VT upper limit
  17. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  18. EP240918b and EP240918c: EP-FXT follow-up observations
  19. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  20. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  21. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  22. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  23. Konus-Wind detection of GRB 240918B
  24. IPN triangulation of GRB 240918B
  25. GRB 240905B: VZLUSAT-2 detection
  26. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  27. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  28. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  29. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  30. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  31. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  32. EP trigger ID 01709059262: correction to the observation start time and source localization
  33. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  34. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  35. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  36. LIGO/Virgo S240919bn: GOTO optical upper limits
  37. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  38. GRB 240918B: AstroSat CZTI detection
  39. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  40. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  41. EP240919a: EP-FXT follow-up observation update
  42. EP240913a/GRB 240913C: 1.6m Mephisto observations
  43. EP240918a: SVOM/VT upper limit
  44. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  45. EP240919a / GRB 240919A: REM optical and NIR upper limits
  46. EP240919a / GRB 240919A: KAIT optical upper limit
  47. EP240918b and EP240918c: Optical upper limits with Kinder observations
  48. GRB 240414A: further radio observations with the VLA
  49. EP240919a: Optical upper limit with Kinder observations
  50. GRB 240919A / EP240919a: SVOM/GRM observation
  51. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  52. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  53. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  54. EP EP240919a: Global MASTER-Net observations report
  55. GRB 240910A: radio detection with the VLA
  56. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  57. EP240919a: NOT and Gemini optical observations
  58. EP240919a: GOTO optical upper limits
  59. EP240919a: JinShan optical upper limits
  60. EP240919a is likely a GRB event
  61. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  62. EP240919a: EP-WXT detection of a fast X-ray transient
  63. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  64. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  65. GRB 240918B: Fermi GBM Detection
  66. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  67. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  68. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  69. EP240918a: EP observation update
  70. GRB 240910A: further Swift observations and confirmation of afterglow
  71. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  72. EP240918a: Swift-XRT observation
  73. Fermi GRB 240918A: Global MASTER-Net observations report
  74. GRB 240918A: Fermi GBM Final Real-time Localization
  75. EP EP240918a: Global MASTER-Net observations report
  76. EP240918a: JinShan optical upper limits
  77. EP240918a: YAHPT Optical Upper Limit
  78. EP240918a: Optical upper limits with Kinder observations
  79. EP240918a: GMG Optical Upper Limit
  80. GRB 240916A: GRBAlpha detection
  81. GRB 240914B: GRBAlpha detection
  82. EP240918a: an X-ray transient detected by Einstein Probe
  83. GRB 240916A: NOT optical observation
  84. GRB 240912A: Swift-BAT refined analysis
  85. IPN triangulation of GRB 240913C / EP 240913a
  86. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  87. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  88. GRB 240916A: Fermi GBM Observation
  89. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  90. GRB 240821A: radio observation with the VLA
  91. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  92. GRB 240916A: Swift-XRT afterglow detection
  93. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  94. GRB 240916A: Swift ToO observations
  95. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  96. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  97. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  98. GRB 240916B: Fermi GBM Final Real-time Localization
  99. GRB 240914B: Fermi GBM Final Localization
  100. The EP-WXT triggers 01709047257 and 01709047278 are not real sources

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