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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"

45779 results found.

  1. EP240918b and EP240918c: EP-FXT follow-up observations
  2. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  3. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  4. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  5. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  6. Konus-Wind detection of GRB 240918B
  7. IPN triangulation of GRB 240918B
  8. GRB 240905B: VZLUSAT-2 detection
  9. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  10. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  11. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  12. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  13. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  14. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  15. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  16. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  18. LIGO/Virgo S240919bn: GOTO optical upper limits
  19. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  20. GRB 240918B: AstroSat CZTI detection
  21. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  23. EP240919a: EP-FXT follow-up observation update
  24. EP240913A/GRB 240913C: AbAO optical upper limit
  25. EP240919a / GRB 240919A: Mondy optical upper limit
  26. EP240913a/GRB 240913C: 1.6m Mephisto observations
  27. EP240918a: SVOM/VT upper limit
  28. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  29. EP240919a / GRB 240919A: REM optical and NIR upper limits
  30. EP240919a / GRB 240919A: KAIT optical upper limit
  31. EP240918b and EP240918c: Optical upper limits with Kinder observations
  32. GRB 240414A: further radio observations with the VLA
  33. EP240919a: Optical upper limit with Kinder observations
  34. GRB 240919A / EP240919a: SVOM/GRM observation
  35. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  36. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  37. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  38. EP EP240919a: Global MASTER-Net observations report
  39. GRB 240910A: radio detection with the VLA
  40. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  41. EP240919a: NOT and Gemini optical observations
  42. EP240919a: GOTO optical upper limits
  43. EP240919a: JinShan optical upper limits
  44. EP240919a is likely a GRB event (duplicate submission of 37563)
  45. EP240919a is likely a GRB event
  46. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  47. EP240919a: EP-WXT detection of a fast X-ray transient
  48. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  49. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  50. GRB 240918B: Fermi GBM Detection
  51. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  52. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  53. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  54. EP240918a: EP observation update
  55. GRB 240910A: further Swift observations and confirmation of afterglow
  56. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  57. EP240918a: Swift-XRT observation
  58. Fermi GRB 240918A: Global MASTER-Net observations report
  59. GRB 240918A: Fermi GBM Final Real-time Localization
  60. EP EP240918a: Global MASTER-Net observations report
  61. EP240918a: JinShan optical upper limits
  62. EP240918a: YAHPT Optical Upper Limit
  63. EP240918a: Optical upper limits with Kinder observations
  64. EP240918a: GMG Optical Upper Limit
  65. GRB 240916A: GRBAlpha detection
  66. GRB 240914B: GRBAlpha detection
  67. EP240918a: an X-ray transient detected by Einstein Probe
  68. GRB 240916A: NOT optical observation
  69. GRB 240912A: Swift-BAT refined analysis
  70. IPN triangulation of GRB 240913C / EP 240913a
  71. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  72. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  73. GRB 240916A: Fermi GBM Observation
  74. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  75. GRB 240821A: radio observation with the VLA
  76. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  77. GRB 240916A: Swift-XRT afterglow detection
  78. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  79. GRB 240916A: Swift ToO observations
  80. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  81. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  82. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  83. GRB 240916B: Fermi GBM Final Real-time Localization
  84. GRB 240914B: Fermi GBM Final Localization
  85. The EP-WXT triggers 01709047257 and 01709047278 are not real sources
  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. GRB 240916A: Fermi GBM Final Real-time Localization
  91. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  92. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  93. EP240913a: VLT/HAWK-I near-infrared upper limits
  94. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  96. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  97. EP240913a/GRB 240913C: KAIT optical upper limit
  98. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  99. GRB 240913C: Fermi GBM detection
  100. GRB 240914A: Swift-XRT observations

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