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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"

28296 results found.

  1. GRB 240825A: LBT optical observations
  2. GRB 240928A: SVOM/GRM observation
  3. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  4. Fermi trigger No 749339671: Global MASTER-Net observations report
  5. GRB 240929A long GRB detected by INTEGRAL
  6. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  7. Swift Trigger 1256950 is probably not a GRB
  8. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  9. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  10. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  11. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  12. GRB 240926A: SVOM/GRM observation
  13. Konus-Wind detection of GRB 240905B
  14. EP240919a / GRB 240919A: SVOM/VT upper limit
  15. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  16. EP240918b and EP240918c: EP-FXT follow-up observations
  17. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  18. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  19. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  20. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  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. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  31. GRB 240918B: AstroSat CZTI detection
  32. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  33. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  34. EP240913A/GRB 240913C: AbAO optical upper limit
  35. EP240919a / GRB 240919A: Mondy optical upper limit
  36. EP240913a/GRB 240913C: 1.6m Mephisto observations
  37. EP240918a: SVOM/VT upper limit
  38. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  39. EP240919a / GRB 240919A: REM optical and NIR upper limits
  40. EP240918b and EP240918c: Optical upper limits with Kinder observations
  41. GRB 240414A: further radio observations with the VLA
  42. EP240919a: Optical upper limit with Kinder observations
  43. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  44. GRB 240910A: radio detection with the VLA
  45. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  46. EP240919a: NOT and Gemini optical observations
  47. EP240919a: GOTO optical upper limits
  48. EP240919a: JinShan optical upper limits
  49. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  50. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  51. GRB 240918B: Fermi GBM Detection
  52. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  53. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  54. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  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. EP240918a: JinShan optical upper limits
  59. EP240918a: Optical upper limits with Kinder observations
  60. EP240918a: GMG Optical Upper Limit
  61. EP240918a: an X-ray transient detected by Einstein Probe
  62. GRB 240912A: Swift-BAT refined analysis
  63. IPN triangulation of GRB 240913C / EP 240913a
  64. GRB 240916A: Fermi GBM Observation
  65. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  66. GRB 240821A: radio observation with the VLA
  67. GRB 240916A: Swift-XRT afterglow detection
  68. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  69. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  70. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  71. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  72. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  73. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  74. EP240913a: VLT/HAWK-I near-infrared upper limits
  75. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  76. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  77. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  78. GRB 240913C: Fermi GBM detection
  79. GRB 240914A: Swift-XRT observations
  80. GRB 240910A: SVOM/VT optical observations
  81. EP240913a: NOT optical upper limits
  82. EP240913a: JinShan optical upper limits
  83. EP240913a: ESO-NTT optical observations
  84. GRB 240914A: ESO-NTT optical observations
  85. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  86. GRB 240905E: further NOT optical observations
  87. EP240913a: EP-WXT detection of a fast X-ray transient
  88. GRB 240911A: LCO optical observations
  89. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  90. GRB 240912A: Swift/UVOT Detection
  91. GRB 240911A: Swift-XRT observations
  92. GRB 240912A: J-band observations with WINTER
  93. GRB 240912A: Swift-XRT refined Analysis
  94. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  95. GRB 240912A: Enhanced Swift-XRT position
  96. GRB 240912A: Redshift from OSIRIS+/GTC
  97. Fast X-ray Transient EP240801a: GMRT radio observations
  98. GRB 240912A: Swift detection of a burst with an optical counterpart
  99. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  100. GRB 240910A: JinShan optical observations

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