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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"

28294 results found.

  1. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  2. Swift Trigger 1256950 is probably not a GRB
  3. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  4. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  5. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  6. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  7. GRB 240926A: SVOM/GRM observation
  8. Konus-Wind detection of GRB 240905B
  9. EP240919a / GRB 240919A: SVOM/VT upper limit
  10. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  11. EP240918b and EP240918c: EP-FXT follow-up observations
  12. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  13. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  14. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  15. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  16. GRB 240905B: VZLUSAT-2 detection
  17. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  18. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  19. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  20. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  21. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  22. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  23. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  24. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  26. GRB 240918B: AstroSat CZTI detection
  27. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  28. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  29. EP240913A/GRB 240913C: AbAO optical upper limit
  30. EP240919a / GRB 240919A: Mondy optical upper limit
  31. EP240913a/GRB 240913C: 1.6m Mephisto observations
  32. EP240918a: SVOM/VT upper limit
  33. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  34. EP240919a / GRB 240919A: REM optical and NIR upper limits
  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. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  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. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  46. GRB 240918B: Fermi GBM Detection
  47. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  48. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  49. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  50. GRB 240910A: further Swift observations and confirmation of afterglow
  51. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  52. EP240918a: Swift-XRT observation
  53. EP240918a: JinShan optical upper limits
  54. EP240918a: Optical upper limits with Kinder observations
  55. EP240918a: GMG Optical Upper Limit
  56. EP240918a: an X-ray transient detected by Einstein Probe
  57. GRB 240912A: Swift-BAT refined analysis
  58. IPN triangulation of GRB 240913C / EP 240913a
  59. GRB 240916A: Fermi GBM Observation
  60. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  61. GRB 240821A: radio observation with the VLA
  62. GRB 240916A: Swift-XRT afterglow detection
  63. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  65. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  66. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  67. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  68. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  69. EP240913a: VLT/HAWK-I near-infrared upper limits
  70. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  72. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  73. GRB 240913C: Fermi GBM detection
  74. GRB 240914A: Swift-XRT observations
  75. GRB 240910A: SVOM/VT optical observations
  76. EP240913a: NOT optical upper limits
  77. EP240913a: JinShan optical upper limits
  78. EP240913a: ESO-NTT optical observations
  79. GRB 240914A: ESO-NTT optical observations
  80. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  81. GRB 240905E: further NOT optical observations
  82. EP240913a: EP-WXT detection of a fast X-ray transient
  83. GRB 240911A: LCO optical observations
  84. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  85. GRB 240912A: Swift/UVOT Detection
  86. GRB 240911A: Swift-XRT observations
  87. GRB 240912A: J-band observations with WINTER
  88. GRB 240912A: Swift-XRT refined Analysis
  89. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  90. GRB 240912A: Enhanced Swift-XRT position
  91. GRB 240912A: Redshift from OSIRIS+/GTC
  92. Fast X-ray Transient EP240801a: GMRT radio observations
  93. GRB 240912A: Swift detection of a burst with an optical counterpart
  94. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  95. GRB 240910A: JinShan optical observations
  96. IPN triangulation of GRB 240905B (short)
  97. GRB 240825A: 7DT Optical Upper Limit
  98. GRB 240905E: SVOM/VT optical observations
  99. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  100. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations

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