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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"

43159 results found.

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

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