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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"

28300 results found.

  1. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  2. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  3. AMON NuEM 240926A: Swift XRT Follow-up
  4. GRB 240929A : Leavitt Observatory optical upper limit
  5. GRB 240825A: LBT optical observations
  6. GRB 240928A: SVOM/GRM observation
  7. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  8. Fermi trigger No 749339671: Global MASTER-Net observations report
  9. GRB 240929A long GRB detected by INTEGRAL
  10. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  11. Swift Trigger 1256950 is probably not a GRB
  12. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  13. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  14. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  15. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  16. GRB 240926A: SVOM/GRM observation
  17. Konus-Wind detection of GRB 240905B
  18. EP240919a / GRB 240919A: SVOM/VT upper limit
  19. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  20. EP240918b and EP240918c: EP-FXT follow-up observations
  21. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  22. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  23. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  24. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  25. GRB 240905B: VZLUSAT-2 detection
  26. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  27. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  28. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  29. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  30. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  31. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  32. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  33. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  34. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  35. GRB 240918B: AstroSat CZTI detection
  36. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  38. EP240913A/GRB 240913C: AbAO optical upper limit
  39. EP240919a / GRB 240919A: Mondy optical upper limit
  40. EP240913a/GRB 240913C: 1.6m Mephisto observations
  41. EP240918a: SVOM/VT upper limit
  42. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  43. EP240919a / GRB 240919A: REM optical and NIR upper limits
  44. EP240918b and EP240918c: Optical upper limits with Kinder observations
  45. GRB 240414A: further radio observations with the VLA
  46. EP240919a: Optical upper limit with Kinder observations
  47. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  48. GRB 240910A: radio detection with the VLA
  49. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  50. EP240919a: NOT and Gemini optical observations
  51. EP240919a: GOTO optical upper limits
  52. EP240919a: JinShan optical upper limits
  53. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  54. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  55. GRB 240918B: Fermi GBM Detection
  56. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  57. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  58. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  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. EP240918a: JinShan optical upper limits
  63. EP240918a: Optical upper limits with Kinder observations
  64. EP240918a: GMG Optical Upper Limit
  65. EP240918a: an X-ray transient detected by Einstein Probe
  66. GRB 240912A: Swift-BAT refined analysis
  67. IPN triangulation of GRB 240913C / EP 240913a
  68. GRB 240916A: Fermi GBM Observation
  69. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  70. GRB 240821A: radio observation with the VLA
  71. GRB 240916A: Swift-XRT afterglow detection
  72. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  74. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  75. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  76. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  77. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  78. EP240913a: VLT/HAWK-I near-infrared upper limits
  79. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  81. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  82. GRB 240913C: Fermi GBM detection
  83. GRB 240914A: Swift-XRT observations
  84. GRB 240910A: SVOM/VT optical observations
  85. EP240913a: NOT optical upper limits
  86. EP240913a: JinShan optical upper limits
  87. EP240913a: ESO-NTT optical observations
  88. GRB 240914A: ESO-NTT optical observations
  89. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  90. GRB 240905E: further NOT optical observations
  91. EP240913a: EP-WXT detection of a fast X-ray transient
  92. GRB 240911A: LCO optical observations
  93. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  94. GRB 240912A: Swift/UVOT Detection
  95. GRB 240911A: Swift-XRT observations
  96. GRB 240912A: J-band observations with WINTER
  97. GRB 240912A: Swift-XRT refined Analysis
  98. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  99. GRB 240912A: Enhanced Swift-XRT position
  100. GRB 240912A: Redshift from OSIRIS+/GTC

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