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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"

45783 results found.

  1. GRB 240529A: FRAM-ORM early optical afterglow observations reveal plateau and rebrightening
  2. GW S240915b and S240919bn : Swift UVOT follow-up
  3. EP240919a / GRB 240919A: SVOM/VT upper limit
  4. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  5. EP240918b and EP240918c: EP-FXT follow-up observations
  6. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  7. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  8. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  9. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  10. Konus-Wind detection of GRB 240918B
  11. IPN triangulation of GRB 240918B
  12. GRB 240905B: VZLUSAT-2 detection
  13. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  14. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  15. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  16. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  17. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  18. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  19. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  20. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S240919bn: GOTO optical upper limits
  23. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  24. GRB 240918B: AstroSat CZTI detection
  25. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  26. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  27. EP240919a: EP-FXT follow-up observation update
  28. EP240913A/GRB 240913C: AbAO optical upper limit
  29. EP240919a / GRB 240919A: Mondy optical upper limit
  30. EP240913a/GRB 240913C: 1.6m Mephisto observations
  31. EP240918a: SVOM/VT upper limit
  32. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  33. EP240919a / GRB 240919A: REM optical and NIR upper limits
  34. EP240919a / GRB 240919A: KAIT optical upper limit
  35. EP240918b and EP240918c: Optical upper limits with Kinder observations
  36. GRB 240414A: further radio observations with the VLA
  37. EP240919a: Optical upper limit with Kinder observations
  38. GRB 240919A / EP240919a: SVOM/GRM observation
  39. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  40. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  41. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  42. EP EP240919a: Global MASTER-Net observations report
  43. GRB 240910A: radio detection with the VLA
  44. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  45. EP240919a: NOT and Gemini optical observations
  46. EP240919a: GOTO optical upper limits
  47. EP240919a: JinShan optical upper limits
  48. EP240919a is likely a GRB event (duplicate submission of 37563)
  49. EP240919a is likely a GRB event
  50. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  51. EP240919a: EP-WXT detection of a fast X-ray transient
  52. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  53. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  54. GRB 240918B: Fermi GBM Detection
  55. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  56. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  57. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  58. EP240918a: EP observation update
  59. GRB 240910A: further Swift observations and confirmation of afterglow
  60. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  61. EP240918a: Swift-XRT observation
  62. Fermi GRB 240918A: Global MASTER-Net observations report
  63. GRB 240918A: Fermi GBM Final Real-time Localization
  64. EP EP240918a: Global MASTER-Net observations report
  65. EP240918a: JinShan optical upper limits
  66. EP240918a: YAHPT Optical Upper Limit
  67. EP240918a: Optical upper limits with Kinder observations
  68. EP240918a: GMG Optical Upper Limit
  69. GRB 240916A: GRBAlpha detection
  70. GRB 240914B: GRBAlpha detection
  71. EP240918a: an X-ray transient detected by Einstein Probe
  72. GRB 240916A: NOT optical observation
  73. GRB 240912A: Swift-BAT refined analysis
  74. IPN triangulation of GRB 240913C / EP 240913a
  75. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  76. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  77. GRB 240916A: Fermi GBM Observation
  78. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  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. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  83. GRB 240916A: Swift ToO observations
  84. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  85. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  86. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  87. GRB 240916B: Fermi GBM Final Real-time Localization
  88. GRB 240914B: Fermi GBM Final Localization
  89. The EP-WXT triggers 01709047257 and 01709047278 are not real sources
  90. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  91. EP EP240913a: Global MASTER-Net observations report
  92. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  93. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  94. GRB 240916A: Fermi GBM Final Real-time Localization
  95. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  96. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  97. EP240913a: VLT/HAWK-I near-infrared upper limits
  98. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  99. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  100. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate

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