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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"

24508 results found.

  1. NuEm-240926A: Upper limits from a search for coincident neutrino events in IceCube
  2. GRB241001A: REM optical/NIR upper limits
  3. LIGO/Virgo/KAGRA S241002e: Updated Sky localization
  4. GRB 241002A: LCOGT Optical Upper Limits
  5. GRB 241001A: VLT/X-shooter redshift
  6. GRB 241002B: GOTO optical counterpart candidate
  7. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  8. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  9. GRB 240929A: Liverpool Telescope prompt followup observations
  10. Fermi GRB 241002B: Global MASTER-Net observations report
  11. GRB 241001A: Swift-XRT observations
  12. GRB 241002B: Fermi GBM Final Real-time Localization
  13. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  14. GRB 241002A: Swift detection of a burst
  15. LIGO/Virgo/KAGRA S240930du: Updated Sky localization
  16. GRB 240930B: Fermi GBM Observation
  17. GRB 240930B: GRBAlpha detection
  18. GRB 240929A: GRBAlpha detection
  19. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  20. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  21. EP240930a: EP-FXT follow-up observation update
  22. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  23. EP240930a: GOTO optical upper limits
  24. GRB 240929A: SVOM/GRM observation
  25. EP EP240930a: Global MASTER-Net observations report
  26. EP240930a: EP-WXT detection of a fast X-ray transient
  27. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  28. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  29. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  30. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  31. AMON NuEM 240926A: Swift XRT Follow-up
  32. Fermi GRB 240930B: Global MASTER-Net observations report
  33. GRB 240930B: Fermi GBM Final Real-time Localization
  34. IPN triangulation of GRB 240926A
  35. GRB 240825A: LBT optical observations
  36. GRB 240928A: SVOM/GRM observation
  37. Fermi GRB 240930A: Global MASTER-Net observations report
  38. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  39. GRB 240930A: Fermi GBM Final Real-time Localization
  40. Fermi trigger No 749339671: Global MASTER-Net observations report
  41. GRB 240929A long GRB detected by INTEGRAL
  42. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  43. Fermi GRB 240929A: Global MASTER-Net observations report
  44. GRB 240929A: Fermi GBM Final Real-time Localization
  45. Integral GRB240929.83: Global MASTER-Net observations report
  46. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  47. Konus-Wind detection of GRB 240912A
  48. Swift Trigger 1256950 is probably not a GRB
  49. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  52. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  53. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  54. GRB 240926A: SVOM/GRM observation
  55. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  56. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240926A
  57. Konus-Wind detection of GRB 240905B
  58. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  59. EP240919a / GRB 240919A: SVOM/VT upper limit
  60. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  61. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  62. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  63. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  64. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  65. Konus-Wind detection of GRB 240918B
  66. IPN triangulation of GRB 240918B
  67. GRB 240905B: VZLUSAT-2 detection
  68. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  69. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  70. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  71. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  72. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  73. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  74. EP trigger ID 01709059262: correction to the observation start time and source localization
  75. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  76. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  77. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  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. EP240913a/GRB 240913C: 1.6m Mephisto observations
  81. EP240918a: SVOM/VT upper limit
  82. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  83. EP240919a / GRB 240919A: REM optical and NIR upper limits
  84. GRB 240919A / EP240919a: SVOM/GRM observation
  85. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  86. EP EP240919a: Global MASTER-Net observations report
  87. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  88. EP240919a: NOT and Gemini optical observations
  89. EP240919a: GOTO optical upper limits
  90. EP240919a is likely a GRB event
  91. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  92. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  93. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  94. GRB 240918B: Fermi GBM Detection
  95. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  96. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  97. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  98. Fermi GRB 240918A: Global MASTER-Net observations report
  99. GRB 240918A: Fermi GBM Final Real-time Localization
  100. EP EP240918a: Global MASTER-Net observations report

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