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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"

23611 results found.

  1. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  2. GRB 241001A: Swift-XRT afterglow detection
  3. GRB 241006A: Enhanced Swift-XRT position
  4. GRB 241006A: Swift detection of a burst
  5. GRB 240930B: SVOM/C-GFT optical upper limit
  6. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  7. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  8. GRB 241002B: Swift-XRT observations
  9. GRB 241002C: SVOM/C-GFT optical upper limit
  10. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  11. Konus-Wind detection of GRB 240926A
  12. GRB 241002B: PRIME near-infrared detection
  13. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  14. IPN triangulation of GRB 240930B / EP 240930a
  15. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update
  16. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  17. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  18. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  19. GRB 241002C : MITSuME Akeno optical upper limits
  20. GRB241001A: REM optical/NIR upper limits
  21. GRB 241002A: Swift/UVOT Upper Limits
  22. EP240930a: Liverpool Telescope observations
  23. GRB 241002A: LCOGT Optical Upper Limits
  24. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  25. GRB 241001A: Swift/UVOT Detection
  26. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  27. GRB 240929A: Liverpool Telescope prompt followup observations
  28. GRB 241001A: Swift-XRT observations
  29. GRB241001A: optical afterglow candidate
  30. GRB 241002A: Enhanced Swift-XRT position
  31. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  32. GRB 241002A: Swift detection of a burst
  33. GRB 240930B: Fermi GBM Observation
  34. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  35. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  36. EP240930a: EP-WXT detection of a fast X-ray transient
  37. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  38. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  39. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  40. AMON NuEM 240926A: Swift XRT Follow-up
  41. GRB 240929A : Leavitt Observatory optical upper limit
  42. Fermi GRB 240930B: Global MASTER-Net observations report
  43. IPN triangulation of GRB 240926A
  44. GRB 240825A: LBT optical observations
  45. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  46. Swift Trigger 1256950 is probably not a GRB
  47. EP trigger ID 01709059262: Lick/Kast spectroscopy with 3 m Shane telescope
  48. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  49. EP240919a / GRB 240919A: SVOM/VT upper limit
  50. EP240918b and EP240918c: EP-FXT follow-up observations
  51. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  52. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  53. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  54. IPN triangulation of GRB 240918B
  55. EP trigger ID 01709059262: the X-ray transient is likely a stellar flare event
  56. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo S240919bn: GOTO optical upper limits
  59. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  60. GRB 240918B: AstroSat CZTI detection
  61. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  62. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  63. EP240913A/GRB 240913C: AbAO optical upper limit
  64. EP240919a / GRB 240919A: Mondy optical upper limit
  65. EP240913a/GRB 240913C: 1.6m Mephisto observations
  66. EP240918a: SVOM/VT upper limit
  67. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  68. EP240919a / GRB 240919A: REM optical and NIR upper limits
  69. EP240918b and EP240918c: Optical upper limits with Kinder observations
  70. GRB 240414A: further radio observations with the VLA
  71. EP240919a: Optical upper limit with Kinder observations
  72. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  73. GRB 240910A: radio detection with the VLA
  74. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  75. EP240919a: NOT and Gemini optical observations
  76. EP240919a: GOTO optical upper limits
  77. EP240919a: JinShan optical upper limits
  78. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  80. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  81. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  82. GRB 240910A: further Swift observations and confirmation of afterglow
  83. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  84. EP240918a: JinShan optical upper limits
  85. EP240918a: Optical upper limits with Kinder observations
  86. EP240918a: GMG Optical Upper Limit
  87. EP240918a: an X-ray transient detected by Einstein Probe
  88. GRB 240916A: NOT optical observation
  89. IPN triangulation of GRB 240913C / EP 240913a
  90. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  91. GRB 240821A: radio observation with the VLA
  92. GRB 240916A: Swift-XRT afterglow detection
  93. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  94. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  95. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  96. EP240913a: VLT/HAWK-I near-infrared upper limits
  97. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  99. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  100. GRB 240914A: Swift-XRT observations

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