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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"

21980 results found.

  1. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  2. GRB 241001A : SVOM/VT optical detection
  3. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  4. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  5. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  6. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  7. GRB241001A: REM optical/NIR upper limits
  8. GRB 241002A: Swift/UVOT Upper Limits
  9. EP240930a: Liverpool Telescope observations
  10. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  11. GRB 241001A: Swift/UVOT Detection
  12. GRB 241001A: VLT/X-shooter redshift
  13. GRB 241002B: GOTO optical counterpart candidate
  14. EP trigger ID 01709064214: GOTO confirms detection as a flare star
  15. GRB 240929A: Liverpool Telescope prompt followup observations
  16. Fermi GRB 241002B: Global MASTER-Net observations report
  17. GRB 241001A: Swift-XRT observations
  18. GRB241001A: optical afterglow candidate
  19. GRB 241002A: 1.5m OSN optical upper limit
  20. GRB 241001A: Swift ToO observations
  21. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  22. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  23. EP240930a: GOTO optical upper limits
  24. EP EP240930a: Global MASTER-Net observations report
  25. EP240930a: EP-WXT detection of a fast X-ray transient
  26. AMON NuEM 240926A: Swift XRT Follow-up
  27. GRB 240929A : Leavitt Observatory optical upper limit
  28. Fermi GRB 240930B: Global MASTER-Net observations report
  29. GRB 240825A: LBT optical observations
  30. Fermi GRB 240930A: Global MASTER-Net observations report
  31. Fermi trigger No 749339671: Global MASTER-Net observations report
  32. Fermi GRB 240929A: Global MASTER-Net observations report
  33. Integral GRB240929.83: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  35. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  36. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  37. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  38. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  39. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240926A
  40. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  41. EP240919a / GRB 240919A: SVOM/VT upper limit
  42. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  43. EP240918b and EP240918c: EP-FXT follow-up observations
  44. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  45. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  46. LIGO/Virgo S240919bn: GOTO optical upper limits
  47. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  48. EP240919a: EP-FXT follow-up observation update
  49. EP240913a/GRB 240913C: 1.6m Mephisto observations
  50. EP240918a: SVOM/VT upper limit
  51. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  52. EP240919a / GRB 240919A: REM optical and NIR upper limits
  53. EP240918b and EP240918c: Optical upper limits with Kinder observations
  54. GRB 240414A: further radio observations with the VLA
  55. EP240919a: Optical upper limit with Kinder observations
  56. GRB 240919A / EP240919a: SVOM/GRM observation
  57. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  58. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  59. EP EP240919a: Global MASTER-Net observations report
  60. GRB 240910A: radio detection with the VLA
  61. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  62. EP240919a: NOT and Gemini optical observations
  63. EP240919a: GOTO optical upper limits
  64. EP240919a: JinShan optical upper limits
  65. EP240919a is likely a GRB event
  66. EP240919a: EP-WXT detection of a fast X-ray transient
  67. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  68. GRB 240918B: Fermi GBM Detection
  69. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  70. EP240918a: EP observation update
  71. GRB 240910A: further Swift observations and confirmation of afterglow
  72. Fermi GRB 240918A: Global MASTER-Net observations report
  73. EP EP240918a: Global MASTER-Net observations report
  74. EP240918a: JinShan optical upper limits
  75. EP240918a: Optical upper limits with Kinder observations
  76. EP240918a: an X-ray transient detected by Einstein Probe
  77. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  78. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  79. GRB 240821A: radio observation with the VLA
  80. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  81. GRB 240916A: Swift-XRT afterglow detection
  82. GRB 240916A: Swift ToO observations
  83. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  84. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  85. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  86. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  87. EP EP240913a: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  89. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  90. EP240913a: VLT/HAWK-I near-infrared upper limits
  91. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  92. GRB 240914A: Swift-XRT observations
  93. GRB 240910A: SVOM/VT optical observations
  94. GRB 240914A: Swift ToO observations
  95. EP240913a: NOT optical upper limits
  96. EP240913a: JinShan optical upper limits
  97. EP240913a: ESO-NTT optical observations
  98. GRB 240914A: ESO-NTT optical observations
  99. GRB 240905E: further NOT optical observations
  100. EP240913a: A GRB Event

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