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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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subject:"Swift"
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submitter:"Judith Racusin"

28295 results found.

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

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