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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"

21940 results found.

  1. GRB 241006A: Swift/UVOT Upper Limits
  2. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  3. GRB 241001A: Swift-XRT afterglow detection
  4. GRB 241006A: Enhanced Swift-XRT position
  5. GRB 241006A: Swift detection of a burst
  6. GRB 240930B: SVOM/C-GFT optical upper limit
  7. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  8. EP trigger ID 01709065118: the X-ray transient is likely a stellar flare event
  9. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  10. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  11. GRB 241002C: SVOM/C-GFT optical upper limit
  12. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  13. Konus-Wind detection of GRB 240926A
  14. GRB 241002B: PRIME near-infrared detection
  15. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  16. IPN triangulation of GRB 240930B / EP 240930a
  17. GRB 241002B: ULL-ASTRO-MASTER LCOGT 0.4m + QHY600 detection of the GOTO optical counterpart candidate AT 2024xbg / GOTO24gpc
  18. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  19. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  20. GRB 241002C : MITSuME Akeno optical upper limits
  21. GRB241001A: REM optical/NIR upper limits
  22. GRB 241002A: Swift/UVOT Upper Limits
  23. EP240930a: Liverpool Telescope observations
  24. GRB 241002A: LCOGT Optical Upper Limits
  25. GRB 241001A: GRANDMA and Kilonova-Catcher optical afterglow detection and upper limits
  26. GRB 241001A: Swift/UVOT Detection
  27. GRB 241002B: GOTO optical counterpart candidate
  28. GRB 241002C : Detection of a long soft transient by SVOM/ECLAIRs
  29. GRB 240929A: Liverpool Telescope prompt followup observations
  30. GRB 241001A: Swift-XRT observations
  31. GRB241001A: optical afterglow candidate
  32. GRB 241002A: Enhanced Swift-XRT position
  33. LIGO/Virgo/KAGRA S241002e: Identification of a GW compact binary merger candidate
  34. GRB 241002A: Swift detection of a burst
  35. GRB 240930B: Fermi GBM Observation
  36. GRB 240930B: GRBAlpha detection
  37. GRB 240929A: GRBAlpha detection
  38. GRB 241001A : Detection of a soft transient by ECLAIRs onboard SVOM
  39. GRB 240930B: Swift/BAT-GUANO localization skymap of a burst
  40. EP240930a: GOTO optical upper limits
  41. EP240930a: EP-WXT detection of a fast X-ray transient
  42. LIGO/Virgo/KAGRA S240930du: Identification of a GW compact binary merger candidate
  43. GRB 240929A : Leavitt Observatory optical upper limit
  44. GRB 240825A: LBT optical observations
  45. LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
  46. GRB 240929A long GRB detected by INTEGRAL
  47. Konus-Wind detection of GRB 240912A
  48. Swift Trigger 1256950 is probably not a GRB
  49. LIGO/Virgo/KAGRA S240921cw: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240920dw: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S240919bn: Upper limits from Swift/BAT-GUANO
  52. NuEm-240926A / IC240926A: BZQJ0955+4532 ~0.6m optical decay and rebrightening detection by MASTER
  53. EP trigger ID 01709061302: the X-ray transient is likely a stellar flare event
  54. Konus-Wind detection of GRB 240905B
  55. EP240919a / GRB 240919A: SVOM/VT upper limit
  56. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  57. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  58. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  59. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  60. GRB 240905B: VZLUSAT-2 detection
  61. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  62. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  63. GRB 240918B: AstroSat CZTI detection
  64. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  65. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  66. EP240913A/GRB 240913C: AbAO optical upper limit
  67. EP240919a / GRB 240919A: Mondy optical upper limit
  68. EP240913a/GRB 240913C: 1.6m Mephisto observations
  69. EP240918a: SVOM/VT upper limit
  70. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  71. EP240919a / GRB 240919A: REM optical and NIR upper limits
  72. EP240918b and EP240918c: Optical upper limits with Kinder observations
  73. GRB 240414A: further radio observations with the VLA
  74. EP240919a: Optical upper limit with Kinder observations
  75. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  76. GRB 240910A: radio detection with the VLA
  77. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  78. EP240919a: NOT and Gemini optical observations
  79. EP240919a: GOTO optical upper limits
  80. EP240919a: JinShan optical upper limits
  81. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  83. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  84. GRB 240910A: further Swift observations and confirmation of afterglow
  85. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  86. EP240918a: JinShan optical upper limits
  87. EP240918a: YAHPT Optical Upper Limit
  88. EP240918a: Optical upper limits with Kinder observations
  89. EP240918a: GMG Optical Upper Limit
  90. GRB 240916A: GRBAlpha detection
  91. GRB 240914B: GRBAlpha detection
  92. EP240918a: an X-ray transient detected by Einstein Probe
  93. IPN triangulation of GRB 240913C / EP 240913a
  94. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  95. GRB 240821A: radio observation with the VLA
  96. GRB 240916A: Swift-XRT afterglow detection
  97. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  98. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  99. EP240913a: VLT/HAWK-I near-infrared upper limits
  100. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate

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